diff --git a/contrib/perf.py b/contrib/perf.py
--- a/contrib/perf.py
+++ b/contrib/perf.py
@@ -1379,7 +1379,7 @@ def perfmanifest(ui, repo, rev, manifest
                     t = repo.manifestlog._revlog.lookup(rev)
             except ValueError:
                 raise error.Abort(
-                    b'manifest revision must be integer or full ' b'node'
+                    b'manifest revision must be integer or full node'
                 )
 
     def d():
diff --git a/hgext/acl.py b/hgext/acl.py
--- a/hgext/acl.py
+++ b/hgext/acl.py
@@ -439,7 +439,7 @@ def _txnhook(ui, repo, hooktype, node, s
         branch = ctx.branch()
         if denybranches and denybranches(branch):
             raise error.Abort(
-                _(b'acl: user "%s" denied on branch "%s"' b' (changeset "%s")')
+                _(b'acl: user "%s" denied on branch "%s" (changeset "%s")')
                 % (user, branch, ctx)
             )
         if allowbranches and not allowbranches(branch):
@@ -457,7 +457,7 @@ def _txnhook(ui, repo, hooktype, node, s
         for f in ctx.files():
             if deny and deny(f):
                 raise error.Abort(
-                    _(b'acl: user "%s" denied on "%s"' b' (changeset "%s")')
+                    _(b'acl: user "%s" denied on "%s" (changeset "%s")')
                     % (user, f, ctx)
                 )
             if allow and not allow(f):
diff --git a/hgext/convert/common.py b/hgext/convert/common.py
--- a/hgext/convert/common.py
+++ b/hgext/convert/common.py
@@ -169,7 +169,7 @@ class converter_source(object):
         """
         if not re.match(br'[0-9a-fA-F]{40,40}$', revstr):
             raise error.Abort(
-                _(b'%s entry %s is not a valid revision' b' identifier')
+                _(b'%s entry %s is not a valid revision identifier')
                 % (mapname, revstr)
             )
 
diff --git a/hgext/convert/cvsps.py b/hgext/convert/cvsps.py
--- a/hgext/convert/cvsps.py
+++ b/hgext/convert/cvsps.py
@@ -124,7 +124,7 @@ def createlog(ui, directory=None, root=b
     re_01 = re.compile(b'cvs \\[r?log aborted\\]: (.+)$')
     re_02 = re.compile(b'cvs (r?log|server): (.+)\n$')
     re_03 = re.compile(
-        b"(Cannot access.+CVSROOT)|" b"(can't create temporary directory.+)$"
+        b"(Cannot access.+CVSROOT)|(can't create temporary directory.+)$"
     )
     re_10 = re.compile(b'Working file: (.+)$')
     re_20 = re.compile(b'symbolic names:')
@@ -328,7 +328,7 @@ def createlog(ui, directory=None, root=b
                 state = 5
             else:
                 assert not re_32.match(line), _(
-                    b'must have at least ' b'some revisions'
+                    b'must have at least some revisions'
                 )
 
         elif state == 5:
@@ -563,7 +563,7 @@ def createlog(ui, directory=None, root=b
                     raise error.Abort(
                         inst,
                         hint=_(
-                            b'check convert.cvsps.logencoding' b' configuration'
+                            b'check convert.cvsps.logencoding configuration'
                         ),
                     )
             else:
@@ -573,9 +573,7 @@ def createlog(ui, directory=None, root=b
                         b" CVS log message for %s of %s"
                     )
                     % (revstr(entry.revision), entry.file),
-                    hint=_(
-                        b'check convert.cvsps.logencoding' b' configuration'
-                    ),
+                    hint=_(b'check convert.cvsps.logencoding configuration'),
                 )
 
     hook.hook(ui, None, b"cvslog", True, log=log)
diff --git a/hgext/convert/git.py b/hgext/convert/git.py
--- a/hgext/convert/git.py
+++ b/hgext/convert/git.py
@@ -259,7 +259,7 @@ class convert_git(common.converter_sourc
             # This can happen if a file is in the repo that has permissions
             # 160000, but there is no .gitmodules file.
             self.ui.warn(
-                _(b"warning: cannot read submodules config file in " b"%s\n")
+                _(b"warning: cannot read submodules config file in %s\n")
                 % version
             )
             return
diff --git a/hgext/convert/monotone.py b/hgext/convert/monotone.py
--- a/hgext/convert/monotone.py
+++ b/hgext/convert/monotone.py
@@ -263,7 +263,7 @@ class monotone_source(common.converter_s
     def getchanges(self, rev, full):
         if full:
             raise error.Abort(
-                _(b"convert from monotone does not support " b"--full")
+                _(b"convert from monotone does not support --full")
             )
         revision = self.mtnrun(b"get_revision", rev).split(b"\n\n")
         files = {}
@@ -369,7 +369,7 @@ class monotone_source(common.converter_s
             version = float(versionstr)
         except Exception:
             raise error.Abort(
-                _(b"unable to determine mtn automate interface " b"version")
+                _(b"unable to determine mtn automate interface version")
             )
 
         if version >= 12.0:
diff --git a/hgext/convert/subversion.py b/hgext/convert/subversion.py
--- a/hgext/convert/subversion.py
+++ b/hgext/convert/subversion.py
@@ -189,7 +189,7 @@ def debugsvnlog(ui, **opts):
     """
     if svn is None:
         raise error.Abort(
-            _(b'debugsvnlog could not load Subversion python ' b'bindings')
+            _(b'debugsvnlog could not load Subversion python bindings')
         )
 
     args = decodeargs(ui.fin.read())
@@ -647,7 +647,7 @@ class svn_source(converter_source):
             revstr,
         ):
             raise error.Abort(
-                _(b'%s entry %s is not a valid revision' b' identifier')
+                _(b'%s entry %s is not a valid revision identifier')
                 % (mapname, revstr)
             )
 
diff --git a/hgext/eol.py b/hgext/eol.py
--- a/hgext/eol.py
+++ b/hgext/eol.py
@@ -460,7 +460,7 @@ def reposetup(ui, repo):
                     continue
                 if inconsistenteol(data):
                     raise errormod.Abort(
-                        _(b"inconsistent newline style " b"in %s\n") % f
+                        _(b"inconsistent newline style in %s\n") % f
                     )
             return super(eolrepo, self).commitctx(ctx, error, origctx)
 
diff --git a/hgext/fastannotate/commands.py b/hgext/fastannotate/commands.py
--- a/hgext/fastannotate/commands.py
+++ b/hgext/fastannotate/commands.py
@@ -93,7 +93,7 @@ fastannotatecommandargs = {
             b'l',
             b'line-number',
             None,
-            _(b'show line number at the first ' b'appearance'),
+            _(b'show line number at the first appearance'),
         ),
         (
             b'e',
@@ -127,7 +127,7 @@ fastannotatecommandargs = {
             b'',
             b'rebuild',
             None,
-            _(b'rebuild cache even if it exists ' b'(EXPERIMENTAL)'),
+            _(b'rebuild cache even if it exists (EXPERIMENTAL)'),
         ),
     ]
     + commands.diffwsopts
diff --git a/hgext/fastannotate/support.py b/hgext/fastannotate/support.py
--- a/hgext/fastannotate/support.py
+++ b/hgext/fastannotate/support.py
@@ -116,7 +116,7 @@ def _fctxannotate(
         return _doannotate(self, follow, diffopts)
     except Exception as ex:
         self._repo.ui.debug(
-            b'fastannotate: falling back to the vanilla ' b'annotate: %r\n' % ex
+            b'fastannotate: falling back to the vanilla annotate: %r\n' % ex
         )
         return orig(self, follow=follow, skiprevs=skiprevs, diffopts=diffopts)
 
diff --git a/hgext/fetch.py b/hgext/fetch.py
--- a/hgext/fetch.py
+++ b/hgext/fetch.py
@@ -188,7 +188,7 @@ def fetch(ui, repo, source=b'default', *
                 message, opts[b'user'], opts[b'date'], editor=editor
             )
             ui.status(
-                _(b'new changeset %d:%s merges remote changes ' b'with local\n')
+                _(b'new changeset %d:%s merges remote changes with local\n')
                 % (repo.changelog.rev(n), short(n))
             )
 
diff --git a/hgext/fix.py b/hgext/fix.py
--- a/hgext/fix.py
+++ b/hgext/fix.py
@@ -423,7 +423,7 @@ def checknodescendants(repo, revs):
         b'(%ld::) - (%ld)', revs, revs
     ):
         raise error.Abort(
-            _(b'can only fix a changeset together ' b'with all its descendants')
+            _(b'can only fix a changeset together with all its descendants')
         )
 
 
diff --git a/hgext/githelp.py b/hgext/githelp.py
--- a/hgext/githelp.py
+++ b/hgext/githelp.py
@@ -66,7 +66,7 @@ def githelp(ui, repo, *args, **kwargs):
 
     if len(args) == 0 or (len(args) == 1 and args[0] == b'git'):
         raise error.Abort(
-            _(b'missing git command - ' b'usage: hg githelp -- <git command>')
+            _(b'missing git command - usage: hg githelp -- <git command>')
         )
 
     if args[0] == b'git':
diff --git a/hgext/gpg.py b/hgext/gpg.py
--- a/hgext/gpg.py
+++ b/hgext/gpg.py
@@ -76,7 +76,7 @@ class gpg(object):
             fp = os.fdopen(fd, r'wb')
             fp.write(data)
             fp.close()
-            gpgcmd = b"%s --logger-fd 1 --status-fd 1 --verify " b"\"%s\" \"%s\"" % (
+            gpgcmd = b"%s --logger-fd 1 --status-fd 1 --verify \"%s\" \"%s\"" % (
                 self.path,
                 sigfile,
                 datafile,
@@ -179,12 +179,12 @@ def getkeys(ui, repo, mygpg, sigdata, co
             continue
         if key[0] == b"EXPSIG":
             ui.write(
-                _(b"%s Note: Signature has expired" b" (signed by: \"%s\")\n")
+                _(b"%s Note: Signature has expired (signed by: \"%s\")\n")
                 % (prefix, key[2])
             )
         elif key[0] == b"EXPKEYSIG":
             ui.write(
-                _(b"%s Note: This key has expired" b" (signed by: \"%s\")\n")
+                _(b"%s Note: This key has expired (signed by: \"%s\")\n")
                 % (prefix, key[2])
             )
         validkeys.append((key[1], key[2], key[3]))
@@ -304,7 +304,7 @@ def _dosign(ui, repo, *revs, **opts):
         ]
         if len(nodes) > 1:
             raise error.Abort(
-                _(b'uncommitted merge - please provide a ' b'specific revision')
+                _(b'uncommitted merge - please provide a specific revision')
             )
         if not nodes:
             nodes = [repo.changelog.tip()]
diff --git a/hgext/highlight/highlight.py b/hgext/highlight/highlight.py
--- a/hgext/highlight/highlight.py
+++ b/hgext/highlight/highlight.py
@@ -39,7 +39,7 @@ TextLexer = pygments.lexers.TextLexer
 HtmlFormatter = pygments.formatters.HtmlFormatter
 
 SYNTAX_CSS = (
-    b'\n<link rel="stylesheet" href="{url}highlightcss" ' b'type="text/css" />'
+    b'\n<link rel="stylesheet" href="{url}highlightcss" type="text/css" />'
 )
 
 
diff --git a/hgext/histedit.py b/hgext/histedit.py
--- a/hgext/histedit.py
+++ b/hgext/histedit.py
@@ -1884,7 +1884,7 @@ def _validateargs(ui, repo, state, freea
     elif goal == b'edit-plan':
         if any((outg, revs, freeargs)):
             raise error.Abort(
-                _(b'only --commands argument allowed with ' b'--edit-plan')
+                _(b'only --commands argument allowed with --edit-plan')
             )
     else:
         if state.inprogress():
diff --git a/hgext/infinitepush/sqlindexapi.py b/hgext/infinitepush/sqlindexapi.py
--- a/hgext/infinitepush/sqlindexapi.py
+++ b/hgext/infinitepush/sqlindexapi.py
@@ -70,7 +70,7 @@ class sqlindexapi(indexapi.indexapi):
             raise indexapi.indexexception(b"SQL connection already open")
         if self.sqlcursor:
             raise indexapi.indexexception(
-                b"SQL cursor already open without" b" connection"
+                b"SQL cursor already open without connection"
             )
         retry = 3
         while True:
@@ -126,7 +126,7 @@ class sqlindexapi(indexapi.indexapi):
             self.sqlconnect()
         self.log.info(b"ADD BUNDLE %r %r" % (self.reponame, bundleid))
         self.sqlcursor.execute(
-            b"INSERT INTO bundles(bundle, reponame) VALUES " b"(%s, %s)",
+            b"INSERT INTO bundles(bundle, reponame) VALUES (%s, %s)",
             params=(bundleid, self.reponame),
         )
         for ctx in nodesctx:
diff --git a/hgext/mq.py b/hgext/mq.py
--- a/hgext/mq.py
+++ b/hgext/mq.py
@@ -593,7 +593,7 @@ class queue(object):
             diffopts.git = self.gitmode == b'yes'
         else:
             raise error.Abort(
-                _(b'mq.git option can be auto/keep/yes/no' b' got %s')
+                _(b'mq.git option can be auto/keep/yes/no got %s')
                 % self.gitmode
             )
         if patchfn:
@@ -1113,7 +1113,7 @@ class queue(object):
 
             if patcherr:
                 self.ui.warn(
-                    _(b"patch failed, rejects left in working " b"directory\n")
+                    _(b"patch failed, rejects left in working directory\n")
                 )
                 err = 2
                 break
@@ -1214,7 +1214,7 @@ class queue(object):
     def delete(self, repo, patches, opts):
         if not patches and not opts.get(b'rev'):
             raise error.Abort(
-                _(b'qdelete requires at least one revision or ' b'patch name')
+                _(b'qdelete requires at least one revision or patch name')
             )
 
         realpatches = []
@@ -1295,7 +1295,7 @@ class queue(object):
         if name != name.strip():
             # whitespace is stripped by parseseries()
             raise error.Abort(
-                _(b'patch name cannot begin or end with ' b'whitespace')
+                _(b'patch name cannot begin or end with whitespace')
             )
         for prefix in (b'.hg', b'.mq'):
             if name.startswith(prefix):
@@ -1629,11 +1629,11 @@ class queue(object):
                     )
                 if move:
                     raise error.Abort(
-                        _(b'cannot use --exact and --move ' b'together')
+                        _(b'cannot use --exact and --move together')
                     )
                 if self.applied:
                     raise error.Abort(
-                        _(b'cannot push --exact with applied ' b'patches')
+                        _(b'cannot push --exact with applied patches')
                     )
                 root = self.series[start]
                 target = patchheader(self.join(root), self.plainmode).parent
@@ -2390,7 +2390,7 @@ class queue(object):
         if rev:
             if files:
                 raise error.Abort(
-                    _(b'option "-r" not valid when importing ' b'files')
+                    _(b'option "-r" not valid when importing files')
                 )
             rev = scmutil.revrange(repo, rev)
             rev.sort(reverse=True)
@@ -2398,7 +2398,7 @@ class queue(object):
             raise error.Abort(_(b'no files or revisions specified'))
         if (len(files) > 1 or len(rev) > 1) and patchname:
             raise error.Abort(
-                _(b'option "-n" not valid when importing multiple ' b'patches')
+                _(b'option "-n" not valid when importing multiple patches')
             )
         imported = []
         if rev:
@@ -2408,7 +2408,7 @@ class queue(object):
             heads = repo.changelog.heads(repo.changelog.node(rev.first()))
             if len(heads) > 1:
                 raise error.Abort(
-                    _(b'revision %d is the root of more than one ' b'branch')
+                    _(b'revision %d is the root of more than one branch')
                     % rev.last()
                 )
             if self.applied:
@@ -2419,7 +2419,7 @@ class queue(object):
                     )
                 if heads != [self.applied[-1].node]:
                     raise error.Abort(
-                        _(b'revision %d is not the parent of ' b'the queue')
+                        _(b'revision %d is not the parent of the queue')
                         % rev.first()
                     )
                 base = repo.changelog.rev(self.applied[0].node)
@@ -2447,7 +2447,7 @@ class queue(object):
                         )
                     if lastparent and lastparent != r:
                         raise error.Abort(
-                            _(b'revision %d is not the parent of ' b'%d')
+                            _(b'revision %d is not the parent of %d')
                             % (r, lastparent)
                         )
                     lastparent = p1
@@ -2849,7 +2849,7 @@ def clone(ui, source, dest=None, **opts)
         hg.peer(ui, opts, patchespath)
     except error.RepoError:
         raise error.Abort(
-            _(b'versioned patch repository not found' b' (see init --mq)')
+            _(b'versioned patch repository not found (see init --mq)')
         )
     qbase, destrev = None, None
     if sr.local():
@@ -3359,7 +3359,7 @@ def guard(ui, repo, *args, **opts):
     if opts.get(r'list'):
         if args or opts.get(r'none'):
             raise error.Abort(
-                _(b'cannot mix -l/--list with options or ' b'arguments')
+                _(b'cannot mix -l/--list with options or arguments')
             )
         for i in pycompat.xrange(len(q.series)):
             status(i)
@@ -3671,13 +3671,12 @@ def save(ui, repo, **opts):
             if os.path.exists(newpath):
                 if not os.path.isdir(newpath):
                     raise error.Abort(
-                        _(b'destination %s exists and is not ' b'a directory')
+                        _(b'destination %s exists and is not a directory')
                         % newpath
                     )
                 if not opts.get(b'force'):
                     raise error.Abort(
-                        _(b'destination %s exists, ' b'use -f to force')
-                        % newpath
+                        _(b'destination %s exists, use -f to force') % newpath
                     )
         else:
             newpath = savename(path)
@@ -4157,7 +4156,7 @@ def reposetup(ui, repo):
             for patch in mqtags:
                 if patch[1] in tags:
                     self.ui.warn(
-                        _(b'tag %s overrides mq patch of the same ' b'name\n')
+                        _(b'tag %s overrides mq patch of the same name\n')
                         % patch[1]
                     )
                 else:
@@ -4191,13 +4190,13 @@ def mqinit(orig, ui, *args, **kwargs):
         repopath = args[0]
         if not hg.islocal(repopath):
             raise error.Abort(
-                _(b'only a local queue repository ' b'may be initialized')
+                _(b'only a local queue repository may be initialized')
             )
     else:
         repopath = cmdutil.findrepo(encoding.getcwd())
         if not repopath:
             raise error.Abort(
-                _(b'there is no Mercurial repository here ' b'(.hg not found)')
+                _(b'there is no Mercurial repository here (.hg not found)')
             )
     repo = hg.repository(ui, repopath)
     return qinit(ui, repo, True)
diff --git a/hgext/narrow/narrowcommands.py b/hgext/narrow/narrowcommands.py
--- a/hgext/narrow/narrowcommands.py
+++ b/hgext/narrow/narrowcommands.py
@@ -249,7 +249,7 @@ def _narrow(
         if not force:
             raise error.Abort(
                 _(b'local changes found'),
-                hint=_(b'use --force-delete-local-changes to ' b'ignore'),
+                hint=_(b'use --force-delete-local-changes to ignore'),
             )
 
     with ui.uninterruptible():
diff --git a/hgext/notify.py b/hgext/notify.py
--- a/hgext/notify.py
+++ b/hgext/notify.py
@@ -377,7 +377,7 @@ class notifier(object):
                 continue
         if len(subs) == 0:
             self.ui.debug(
-                b'notify: no subscribers to selected repo ' b'and revset\n'
+                b'notify: no subscribers to selected repo and revset\n'
             )
             return
 
diff --git a/hgext/patchbomb.py b/hgext/patchbomb.py
--- a/hgext/patchbomb.py
+++ b/hgext/patchbomb.py
@@ -162,7 +162,7 @@ def _addpullheader(seq, ctx):
     # destination before patchbombing anything.
     publicurl = repo.ui.config(b'patchbomb', b'publicurl')
     if publicurl:
-        return b'Available At %s\n' b'#              hg pull %s -r %s' % (
+        return b'Available At %s\n#              hg pull %s -r %s' % (
             publicurl,
             publicurl,
             ctx,
@@ -343,9 +343,7 @@ def _getpatches(repo, revs, **opts):
     prev = repo[b'.'].rev()
     for r in revs:
         if r == prev and (repo[None].files() or repo[None].deleted()):
-            ui.warn(
-                _(b'warning: working directory has ' b'uncommitted changes\n')
-            )
+            ui.warn(_(b'warning: working directory has uncommitted changes\n'))
         output = stringio()
         cmdutil.exportfile(
             repo, [r], output, opts=patch.difffeatureopts(ui, opts, git=True)
@@ -391,7 +389,7 @@ def _getdescription(repo, defaultbody, s
         body = open(opts.get(r'desc')).read()
     else:
         ui.write(
-            _(b'\nWrite the introductory message for the ' b'patch series.\n\n')
+            _(b'\nWrite the introductory message for the patch series.\n\n')
         )
         body = ui.edit(
             defaultbody, sender, repopath=repo.path, action=b'patchbombbody'
@@ -911,7 +909,7 @@ def email(ui, repo, *revs, **opts):
                 ui.write(ds, label=b'patchbomb.diffstats')
         ui.write(b'\n')
         if ui.promptchoice(
-            _(b'are you sure you want to send (yn)?' b'$$ &Yes $$ &No')
+            _(b'are you sure you want to send (yn)?$$ &Yes $$ &No')
         ):
             raise error.Abort(_(b'patchbomb canceled'))
 
diff --git a/hgext/phabricator.py b/hgext/phabricator.py
--- a/hgext/phabricator.py
+++ b/hgext/phabricator.py
@@ -830,7 +830,7 @@ def _confirmbeforesend(repo, revs, oldma
         )
 
     if ui.promptchoice(
-        _(b'Send the above changes to %s (yn)?' b'$$ &Yes $$ &No') % url
+        _(b'Send the above changes to %s (yn)?$$ &Yes $$ &No') % url
     ):
         return False
 
diff --git a/hgext/rebase.py b/hgext/rebase.py
--- a/hgext/rebase.py
+++ b/hgext/rebase.py
@@ -469,7 +469,7 @@ class rebaseruntime(object):
                     branches.add(repo[rev].branch())
                     if len(branches) > 1:
                         raise error.Abort(
-                            _(b'cannot collapse multiple named ' b'branches')
+                            _(b'cannot collapse multiple named branches')
                         )
 
         # Calculate self.obsoletenotrebased
@@ -589,14 +589,11 @@ class rebaseruntime(object):
         elif rev in self.obsoletenotrebased:
             succ = self.obsoletenotrebased[rev]
             if succ is None:
-                msg = (
-                    _(b'note: not rebasing %s, it has no ' b'successor\n')
-                    % desc
-                )
+                msg = _(b'note: not rebasing %s, it has no successor\n') % desc
             else:
                 succdesc = _ctxdesc(repo[succ])
                 msg = _(
-                    b'note: not rebasing %s, already in ' b'destination as %s\n'
+                    b'note: not rebasing %s, already in destination as %s\n'
                 ) % (desc, succdesc)
             repo.ui.status(msg)
             # Make clearrebased aware state[rev] is not a true successor
@@ -1111,7 +1108,7 @@ def _dryrunrebase(ui, repo, action, opts
         ui.status(_(b'starting in-memory rebase\n'))
     else:
         ui.status(
-            _(b'starting dry-run rebase; repository will not be ' b'changed\n')
+            _(b'starting dry-run rebase; repository will not be changed\n')
         )
     with repo.wlock(), repo.lock():
         needsabort = True
@@ -1136,9 +1133,7 @@ def _dryrunrebase(ui, repo, action, opts
         else:
             if confirm:
                 ui.status(_(b'rebase completed successfully\n'))
-                if not ui.promptchoice(
-                    _(b'apply changes (yn)?' b'$$ &Yes $$ &No')
-                ):
+                if not ui.promptchoice(_(b'apply changes (yn)?$$ &Yes $$ &No')):
                     # finish unfinished rebase
                     rbsrt._finishrebase()
                 else:
@@ -1415,8 +1410,7 @@ def _definedestmap(
                     ui.note(_(b'skipping %s - empty destination\n') % repo[r])
                 else:
                     raise error.Abort(
-                        _(b'rebase destination for %s is not ' b'unique')
-                        % repo[r]
+                        _(b'rebase destination for %s is not unique') % repo[r]
                     )
 
     if dest is not None:
@@ -1638,7 +1632,7 @@ def _checkobsrebase(repo, ui, rebaseobsr
 
     if divergencebasecandidates and not divergenceok:
         divhashes = (bytes(repo[r]) for r in divergencebasecandidates)
-        msg = _(b"this rebase will cause " b"divergences from: %s")
+        msg = _(b"this rebase will cause divergences from: %s")
         h = _(
             b"to force the rebase please set "
             b"experimental.evolution.allowdivergence=True"
diff --git a/hgext/releasenotes.py b/hgext/releasenotes.py
--- a/hgext/releasenotes.py
+++ b/hgext/releasenotes.py
@@ -300,7 +300,7 @@ def checkadmonitions(ui, repo, directive
                 continue
             else:
                 ui.write(
-                    _(b"Invalid admonition '%s' present in changeset %s" b"\n")
+                    _(b"Invalid admonition '%s' present in changeset %s\n")
                     % (admonition.group(1), ctx.hex()[:12])
                 )
                 sim = lambda x: difflib.SequenceMatcher(
@@ -376,7 +376,7 @@ def parsenotesfromrevisions(repo, direct
             # TODO consider using title as paragraph for more concise notes.
             if not paragraphs:
                 repo.ui.warn(
-                    _(b"error parsing releasenotes for revision: " b"'%s'\n")
+                    _(b"error parsing releasenotes for revision: '%s'\n")
                     % node.hex(ctx.node())
                 )
             if title:
@@ -422,7 +422,7 @@ def parsereleasenotesfile(sections, text
                     continue
             elif block[b'type'] != b'paragraph':
                 raise error.Abort(
-                    _(b'unexpected block type in release notes: ' b'%s')
+                    _(b'unexpected block type in release notes: %s')
                     % block[b'type']
                 )
             if title:
diff --git a/hgext/remotefilelog/__init__.py b/hgext/remotefilelog/__init__.py
--- a/hgext/remotefilelog/__init__.py
+++ b/hgext/remotefilelog/__init__.py
@@ -273,7 +273,7 @@ def uisetup(ui):
             b'',
             b'shallow',
             None,
-            _(b"create a shallow clone which uses remote file " b"history"),
+            _(b"create a shallow clone which uses remote file history"),
         )
     )
 
@@ -796,8 +796,7 @@ def walkfilerevs(orig, repo, match, foll
     for filename in match.files():
         if filename not in pctx:
             raise error.Abort(
-                _(b'cannot follow file not in parent ' b'revision: "%s"')
-                % filename
+                _(b'cannot follow file not in parent revision: "%s"') % filename
             )
         fctx = pctx[filename]
 
diff --git a/hgext/remotefilelog/contentstore.py b/hgext/remotefilelog/contentstore.py
--- a/hgext/remotefilelog/contentstore.py
+++ b/hgext/remotefilelog/contentstore.py
@@ -137,7 +137,7 @@ class unioncontentstore(basestore.baseun
 
     def add(self, name, node, data):
         raise RuntimeError(
-            b"cannot add content only to remotefilelog " b"contentstore"
+            b"cannot add content only to remotefilelog contentstore"
         )
 
     def getmissing(self, keys):
@@ -209,7 +209,7 @@ class remotefilelogcontentstore(basestor
 
     def add(self, name, node, data):
         raise RuntimeError(
-            b"cannot add content only to remotefilelog " b"contentstore"
+            b"cannot add content only to remotefilelog contentstore"
         )
 
     def _sanitizemetacache(self):
diff --git a/hgext/remotefilelog/fileserverclient.py b/hgext/remotefilelog/fileserverclient.py
--- a/hgext/remotefilelog/fileserverclient.py
+++ b/hgext/remotefilelog/fileserverclient.py
@@ -414,7 +414,7 @@ class fileserverclient(object):
                         ):
                             if not isinstance(remote, _sshv1peer):
                                 raise error.Abort(
-                                    b'remotefilelog requires ssh ' b'servers'
+                                    b'remotefilelog requires ssh servers'
                                 )
                             step = self.ui.configint(
                                 b'remotefilelog', b'getfilesstep'
diff --git a/hgext/remotefilelog/metadatastore.py b/hgext/remotefilelog/metadatastore.py
--- a/hgext/remotefilelog/metadatastore.py
+++ b/hgext/remotefilelog/metadatastore.py
@@ -99,7 +99,7 @@ class unionmetadatastore(basestore.baseu
 
     def add(self, name, node, data):
         raise RuntimeError(
-            b"cannot add content only to remotefilelog " b"contentstore"
+            b"cannot add content only to remotefilelog contentstore"
         )
 
     def getmissing(self, keys):
@@ -136,7 +136,7 @@ class remotefilelogmetadatastore(basesto
 
     def add(self, name, node, parents, linknode):
         raise RuntimeError(
-            b"cannot add metadata only to remotefilelog " b"metadatastore"
+            b"cannot add metadata only to remotefilelog metadatastore"
         )
 
 
diff --git a/hgext/remotefilelog/remotefilelogserver.py b/hgext/remotefilelog/remotefilelogserver.py
--- a/hgext/remotefilelog/remotefilelogserver.py
+++ b/hgext/remotefilelog/remotefilelogserver.py
@@ -194,7 +194,7 @@ def onetimesetup(ui):
             # since it would require fetching every version of every
             # file in order to create the revlogs.
             raise error.Abort(
-                _(b"Cannot clone from a shallow repo " b"to a full repo.")
+                _(b"Cannot clone from a shallow repo to a full repo.")
             )
         else:
             for x in orig(repo, matcher):
diff --git a/hgext/remotefilelog/shallowutil.py b/hgext/remotefilelog/shallowutil.py
--- a/hgext/remotefilelog/shallowutil.py
+++ b/hgext/remotefilelog/shallowutil.py
@@ -55,7 +55,7 @@ def getcachepath(ui, allowempty=False):
             return None
         else:
             raise error.Abort(
-                _(b"could not find config option " b"remotefilelog.cachepath")
+                _(b"could not find config option remotefilelog.cachepath")
             )
     return util.expandpath(cachepath)
 
@@ -427,7 +427,7 @@ def readexactly(stream, n):
     s = stream.read(n)
     if len(s) < n:
         raise error.Abort(
-            _(b"stream ended unexpectedly" b" (got %d bytes, expected %d)")
+            _(b"stream ended unexpectedly (got %d bytes, expected %d)")
             % (len(s), n)
         )
     return s
diff --git a/hgext/share.py b/hgext/share.py
--- a/hgext/share.py
+++ b/hgext/share.py
@@ -70,7 +70,7 @@ testedwith = b'ships-with-hg-core'
             b'',
             b'relative',
             None,
-            _(b'point to source using a relative path ' b'(EXPERIMENTAL)'),
+            _(b'point to source using a relative path (EXPERIMENTAL)'),
         ),
     ],
     _(b'[-U] [-B] SOURCE [DEST]'),
diff --git a/hgext/split.py b/hgext/split.py
--- a/hgext/split.py
+++ b/hgext/split.py
@@ -108,7 +108,7 @@ def split(ui, repo, *revs, **opts):
             )
             if not alloworphaned and len(torebase) != len(descendants):
                 raise error.Abort(
-                    _(b'split would leave orphaned changesets ' b'behind')
+                    _(b'split would leave orphaned changesets behind')
                 )
         else:
             if not alloworphaned and descendants:
@@ -164,7 +164,7 @@ def dosplit(ui, repo, tr, ctx, opts):
                 firstline = c.description().split(b'\n', 1)[0]
                 header += _(b'HG: - %s: %s\n') % (short(c.node()), firstline)
             header += _(
-                b'HG: Write commit message for the next split ' b'changeset.\n'
+                b'HG: Write commit message for the next split changeset.\n'
             )
         else:
             header = _(
diff --git a/hgext/sqlitestore.py b/hgext/sqlitestore.py
--- a/hgext/sqlitestore.py
+++ b/hgext/sqlitestore.py
@@ -358,7 +358,7 @@ class sqlitefilestore(object):
 
             if i != rev:
                 raise SQLiteStoreError(
-                    _(b'sqlite database has inconsistent ' b'revision numbers')
+                    _(b'sqlite database has inconsistent revision numbers')
                 )
 
             if p1rev == nullrev:
@@ -772,7 +772,7 @@ class sqlitefilestore(object):
         # SQLite, since columns can be resized at will.
         if len(tombstone) > len(self.rawdata(censornode)):
             raise error.Abort(
-                _(b'censor tombstone must be no longer than ' b'censored data')
+                _(b'censor tombstone must be no longer than censored data')
             )
 
         # We need to replace the censored revision's data with the tombstone.
@@ -1161,7 +1161,7 @@ def newreporequirements(orig, ui, create
     # This restriction can be lifted once we have more confidence.
     if b'sharedrepo' in createopts:
         raise error.Abort(
-            _(b'shared repositories not supported with SQLite ' b'store')
+            _(b'shared repositories not supported with SQLite store')
         )
 
     # This filtering is out of an abundance of caution: we want to ensure
@@ -1176,7 +1176,7 @@ def newreporequirements(orig, ui, create
     unsupported = set(createopts) - known
     if unsupported:
         raise error.Abort(
-            _(b'SQLite store does not support repo creation ' b'option: %s')
+            _(b'SQLite store does not support repo creation option: %s')
             % b', '.join(sorted(unsupported))
         )
 
diff --git a/hgext/strip.py b/hgext/strip.py
--- a/hgext/strip.py
+++ b/hgext/strip.py
@@ -124,24 +124,19 @@ def strip(
             ),
         ),
         (b'', b'no-backup', None, _(b'do not save backup bundle')),
-        (
-            b'',
-            b'nobackup',
-            None,
-            _(b'do not save backup bundle ' b'(DEPRECATED)'),
-        ),
+        (b'', b'nobackup', None, _(b'do not save backup bundle (DEPRECATED)'),),
         (b'n', b'', None, _(b'ignored  (DEPRECATED)')),
         (
             b'k',
             b'keep',
             None,
-            _(b"do not modify working directory during " b"strip"),
+            _(b"do not modify working directory during strip"),
         ),
         (
             b'B',
             b'bookmark',
             [],
-            _(b"remove revs only reachable from given" b" bookmark"),
+            _(b"remove revs only reachable from given bookmark"),
             _(b'BOOKMARK'),
         ),
         (
diff --git a/hgext/transplant.py b/hgext/transplant.py
--- a/hgext/transplant.py
+++ b/hgext/transplant.py
@@ -438,7 +438,7 @@ class transplanter(object):
             p1 = repo.dirstate.p1()
             if p1 != parent:
                 raise error.Abort(
-                    _(b'working directory not at transplant ' b'parent %s')
+                    _(b'working directory not at transplant parent %s')
                     % nodemod.hex(parent)
                 )
             if merge:
@@ -661,7 +661,7 @@ def browserevs(ui, repo, nodes, opts):
             b'c',
             b'continue',
             None,
-            _(b'continue last transplant session ' b'after fixing conflicts'),
+            _(b'continue last transplant session after fixing conflicts'),
         ),
         (
             b'',
@@ -788,7 +788,7 @@ def _dotransplant(ui, repo, *revs, **opt
                 raise error.Abort(_(b'--all requires a branch revision'))
             if revs:
                 raise error.Abort(
-                    _(b'--all is incompatible with a ' b'revision list')
+                    _(b'--all is incompatible with a revision list')
                 )
 
     opts = pycompat.byteskwargs(opts)
diff --git a/hgext/uncommit.py b/hgext/uncommit.py
--- a/hgext/uncommit.py
+++ b/hgext/uncommit.py
@@ -165,7 +165,7 @@ def uncommit(ui, repo, *pats, **opts):
         if not allowdirtywcopy and (not pats or isdirtypath):
             cmdutil.bailifchanged(
                 repo,
-                hint=_(b'requires ' b'--allow-dirty-working-copy to uncommit'),
+                hint=_(b'requires --allow-dirty-working-copy to uncommit'),
             )
         old = repo[b'.']
         rewriteutil.precheck(repo, [old.rev()], b'uncommit')
@@ -190,7 +190,7 @@ def uncommit(ui, repo, *pats, **opts):
             for f in sorted(badfiles):
                 if f in s.clean:
                     hint = _(
-                        b"file was not changed in working directory " b"parent"
+                        b"file was not changed in working directory parent"
                     )
                 elif repo.wvfs.exists(f):
                     hint = _(b"file was untracked in working directory parent")
diff --git a/hgext/win32mbcs.py b/hgext/win32mbcs.py
--- a/hgext/win32mbcs.py
+++ b/hgext/win32mbcs.py
@@ -128,7 +128,7 @@ def basewrapper(func, argtype, enc, dec,
         return enc(func(*dec(args), **dec(kwds)))
     except UnicodeError:
         raise error.Abort(
-            _(b"[win32mbcs] filename conversion failed with" b" %s encoding\n")
+            _(b"[win32mbcs] filename conversion failed with %s encoding\n")
             % _encoding
         )
 
diff --git a/mercurial/bookmarks.py b/mercurial/bookmarks.py
--- a/mercurial/bookmarks.py
+++ b/mercurial/bookmarks.py
@@ -302,7 +302,7 @@ class bmstore(object):
                     )
                     return delbms
             raise error.Abort(
-                _(b"bookmark '%s' already exists " b"(use -f to force)") % mark
+                _(b"bookmark '%s' already exists (use -f to force)") % mark
             )
         if (
             mark in self._repo.branchmap()
@@ -893,7 +893,7 @@ def checkformat(repo, mark):
     mark = mark.strip()
     if not mark:
         raise error.Abort(
-            _(b"bookmark names cannot consist entirely of " b"whitespace")
+            _(b"bookmark names cannot consist entirely of whitespace")
         )
     scmutil.checknewlabel(repo, mark, b'bookmark')
     return mark
diff --git a/mercurial/bundle2.py b/mercurial/bundle2.py
--- a/mercurial/bundle2.py
+++ b/mercurial/bundle2.py
@@ -1233,7 +1233,7 @@ class interrupthandler(unpackermixin):
     def __call__(self):
 
         self.ui.debug(
-            b'bundle2-input-stream-interrupt:' b' opening out of band context\n'
+            b'bundle2-input-stream-interrupt: opening out of band context\n'
         )
         indebug(self.ui, b'bundle2 stream interruption, looking for a part.')
         headerblock = self._readpartheader()
@@ -1252,7 +1252,7 @@ class interrupthandler(unpackermixin):
             if not hardabort:
                 part.consume()
         self.ui.debug(
-            b'bundle2-input-stream-interrupt:' b' closing out of band context\n'
+            b'bundle2-input-stream-interrupt: closing out of band context\n'
         )
 
 
@@ -1320,7 +1320,7 @@ def decodepayloadchunks(ui, fh):
         s = read(headersize)
         if len(s) < headersize:
             raise error.Abort(
-                _(b'stream ended unexpectedly ' b' (got %d bytes, expected %d)')
+                _(b'stream ended unexpectedly  (got %d bytes, expected %d)')
                 % (len(s), chunksize)
             )
 
@@ -1889,7 +1889,7 @@ def writebundle(
         assert compression is None
         if cg.version != b'01':
             raise error.Abort(
-                _(b'old bundle types only supports v1 ' b'changegroups')
+                _(b'old bundle types only supports v1 changegroups')
             )
         header, comp = bundletypes[bundletype]
         if comp not in util.compengines.supportedbundletypes:
@@ -2136,7 +2136,7 @@ def handlecheckheads(op, inpart):
         op.gettransaction()
     if sorted(heads) != sorted(op.repo.heads()):
         raise error.PushRaced(
-            b'remote repository changed while pushing - ' b'please try again'
+            b'remote repository changed while pushing - please try again'
         )
 
 
diff --git a/mercurial/bundlerepo.py b/mercurial/bundlerepo.py
--- a/mercurial/bundlerepo.py
+++ b/mercurial/bundlerepo.py
@@ -269,7 +269,7 @@ class bundlerepository(object):
                 if part.type == b'changegroup':
                     if cgpart:
                         raise NotImplementedError(
-                            b"can't process " b"multiple changegroups"
+                            b"can't process multiple changegroups"
                         )
                     cgpart = part
 
diff --git a/mercurial/changegroup.py b/mercurial/changegroup.py
--- a/mercurial/changegroup.py
+++ b/mercurial/changegroup.py
@@ -1551,7 +1551,7 @@ def getbundler(
 
     if version == b'01' and not matcher.always():
         raise error.ProgrammingError(
-            b'version 01 changegroups do not support ' b'sparse file matchers'
+            b'version 01 changegroups do not support sparse file matchers'
         )
 
     if ellipses and version in (b'01', b'02'):
diff --git a/mercurial/cmdutil.py b/mercurial/cmdutil.py
--- a/mercurial/cmdutil.py
+++ b/mercurial/cmdutil.py
@@ -257,13 +257,9 @@ def resolvecommitoptions(ui, opts):
     the ``date`` option is set.
     """
     if opts.get(b'date') and opts.get(b'currentdate'):
-        raise error.Abort(
-            _(b'--date and --currentdate are mutually ' b'exclusive')
-        )
+        raise error.Abort(_(b'--date and --currentdate are mutually exclusive'))
     if opts.get(b'user') and opts.get(b'currentuser'):
-        raise error.Abort(
-            _(b'--user and --currentuser are mutually ' b'exclusive')
-        )
+        raise error.Abort(_(b'--user and --currentuser are mutually exclusive'))
 
     datemaydiffer = False  # date-only change should be ignored?
 
@@ -1010,7 +1006,7 @@ def logmessage(ui, opts):
 
     if message and logfile:
         raise error.Abort(
-            _(b'options --message and --logfile are mutually ' b'exclusive')
+            _(b'options --message and --logfile are mutually exclusive')
         )
     if not message and logfile:
         try:
@@ -1180,7 +1176,7 @@ def _buildfntemplate(pat, total=None, se
             newname.append(stringutil.escapestr(pat[i:n]))
             if n + 2 > end:
                 raise error.Abort(
-                    _(b"incomplete format spec in output " b"filename")
+                    _(b"incomplete format spec in output filename")
                 )
             c = pat[n + 1 : n + 2]
             i = n + 2
@@ -1188,7 +1184,7 @@ def _buildfntemplate(pat, total=None, se
                 newname.append(expander[c])
             except KeyError:
                 raise error.Abort(
-                    _(b"invalid format spec '%%%s' in output " b"filename") % c
+                    _(b"invalid format spec '%%%s' in output filename") % c
                 )
     return b''.join(newname)
 
@@ -2264,7 +2260,7 @@ def walkchangerevs(repo, match, opts, pr
 
         if follow:
             raise error.Abort(
-                _(b'can only follow copies/renames for explicit ' b'filenames')
+                _(b'can only follow copies/renames for explicit filenames')
             )
 
         # The slow path checks files modified in every changeset.
diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -830,7 +830,7 @@ def _dobackout(ui, repo, node=None, rev=
         hg._showstats(repo, stats)
         if stats.unresolvedcount:
             repo.ui.status(
-                _(b"use 'hg resolve' to retry unresolved " b"file merges\n")
+                _(b"use 'hg resolve' to retry unresolved file merges\n")
             )
             return 1
     else:
@@ -839,7 +839,7 @@ def _dobackout(ui, repo, node=None, rev=
         cmdutil.revert(ui, repo, rctx, repo.dirstate.parents())
 
     if opts.get(b'no_commit'):
-        msg = _(b"changeset %s backed out, " b"don't forget to commit.\n")
+        msg = _(b"changeset %s backed out, don't forget to commit.\n")
         ui.status(msg % short(node))
         return 0
 
@@ -1353,7 +1353,7 @@ def branch(ui, repo, label=None, **opts)
             if not opts.get(b'force') and label in repo.branchmap():
                 if label not in [p.branch() for p in repo[None].parents()]:
                     raise error.Abort(
-                        _(b'a branch of the same name already' b' exists'),
+                        _(b'a branch of the same name already exists'),
                         # i18n: "it" refers to an existing branch
                         hint=_(b"use 'hg update' to switch to it"),
                     )
@@ -1562,9 +1562,7 @@ def bundle(ui, repo, fname, dest=None, *
     except error.UnsupportedBundleSpecification as e:
         raise error.Abort(
             pycompat.bytestr(e),
-            hint=_(
-                b"see 'hg help bundlespec' for supported " b"values for --type"
-            ),
+            hint=_(b"see 'hg help bundlespec' for supported values for --type"),
         )
     cgversion = bundlespec.contentopts[b"cg.version"]
 
@@ -1578,7 +1576,7 @@ def bundle(ui, repo, fname, dest=None, *
     if opts.get(b'all'):
         if dest:
             raise error.Abort(
-                _(b"--all is incompatible with specifying " b"a destination")
+                _(b"--all is incompatible with specifying a destination")
             )
         if opts.get(b'base'):
             ui.warn(_(b"ignoring --base because --all was specified\n"))
@@ -1593,7 +1591,7 @@ def bundle(ui, repo, fname, dest=None, *
     if base:
         if dest:
             raise error.Abort(
-                _(b"--base is incompatible with specifying " b"a destination")
+                _(b"--base is incompatible with specifying a destination")
             )
         common = [repo[rev].node() for rev in base]
         heads = [repo[r].node() for r in revs] if revs else None
@@ -2048,7 +2046,7 @@ def _docommit(ui, repo, *pats, **opts):
 
         if repo[b'.'].closesbranch():
             raise error.Abort(
-                _(b'current revision is already a branch closing' b' head')
+                _(b'current revision is already a branch closing head')
             )
         elif not bheads:
             raise error.Abort(_(b'branch "%s" has no heads to close') % branch)
@@ -2298,7 +2296,7 @@ def continuecmd(ui, repo, **opts):
     if not contstate.continuefunc:
         raise error.Abort(
             (
-                _(b"%s in progress but does not support " b"'hg continue'")
+                _(b"%s in progress but does not support 'hg continue'")
                 % (contstate._opname)
             ),
             hint=contstate.continuemsg(),
@@ -2987,19 +2985,19 @@ def _dograft(ui, repo, *revs, **opts):
     if opts.get(b'no_commit'):
         if opts.get(b'edit'):
             raise error.Abort(
-                _(b"cannot specify --no-commit and " b"--edit together")
+                _(b"cannot specify --no-commit and --edit together")
             )
         if opts.get(b'currentuser'):
             raise error.Abort(
-                _(b"cannot specify --no-commit and " b"--currentuser together")
+                _(b"cannot specify --no-commit and --currentuser together")
             )
         if opts.get(b'currentdate'):
             raise error.Abort(
-                _(b"cannot specify --no-commit and " b"--currentdate together")
+                _(b"cannot specify --no-commit and --currentdate together")
             )
         if opts.get(b'log'):
             raise error.Abort(
-                _(b"cannot specify --no-commit and " b"--log together")
+                _(b"cannot specify --no-commit and --log together")
             )
 
     graftstate = statemod.cmdstate(repo, b'graftstate')
@@ -3007,7 +3005,7 @@ def _dograft(ui, repo, *revs, **opts):
     if opts.get(b'stop'):
         if opts.get(b'continue'):
             raise error.Abort(
-                _(b"cannot use '--continue' and " b"'--stop' together")
+                _(b"cannot use '--continue' and '--stop' together")
             )
         if opts.get(b'abort'):
             raise error.Abort(_(b"cannot use '--abort' and '--stop' together"))
@@ -3028,7 +3026,7 @@ def _dograft(ui, repo, *revs, **opts):
     elif opts.get(b'abort'):
         if opts.get(b'continue'):
             raise error.Abort(
-                _(b"cannot use '--continue' and " b"'--abort' together")
+                _(b"cannot use '--continue' and '--abort' together")
             )
         if any(
             (
@@ -3866,7 +3864,7 @@ def identify(
     opts = pycompat.byteskwargs(opts)
     if not repo and not source:
         raise error.Abort(
-            _(b"there is no Mercurial repository here " b"(.hg not found)")
+            _(b"there is no Mercurial repository here (.hg not found)")
         )
 
     default = not (num or id or branch or tags or bookmarks)
@@ -4904,7 +4902,7 @@ statemod.addunfinished(
     cmdmsg=_(b'outstanding uncommitted merge'),
     abortfunc=hg.abortmerge,
     statushint=_(
-        b'To continue:    hg commit\n' b'To abort:       hg merge --abort'
+        b'To continue:    hg commit\nTo abort:       hg merge --abort'
     ),
     cmdhint=_(b"use 'hg commit' or 'hg merge --abort'"),
 )
@@ -5305,7 +5303,7 @@ def postincoming(ui, repo, modheads, opt
             )
         elif currentbranchheads > 1:
             ui.status(
-                _(b"(run 'hg heads .' to see heads, 'hg merge' to " b"merge)\n")
+                _(b"(run 'hg heads .' to see heads, 'hg merge' to merge)\n")
             )
         else:
             ui.status(_(b"(run 'hg heads' to see heads)\n"))
@@ -5615,7 +5613,7 @@ def push(ui, repo, dest=None, **opts):
         revs = [repo[rev].node() for rev in revs]
         if not revs:
             raise error.Abort(
-                _(b'default push revset for path evaluates to an ' b'empty set')
+                _(b'default push revset for path evaluates to an empty set')
             )
 
     repo._subtoppath = dest
@@ -5882,7 +5880,7 @@ def resolve(ui, repo, *pats, **opts):
     if confirm:
         if all:
             if ui.promptchoice(
-                _(b're-merge all unresolved files (yn)?' b'$$ &Yes $$ &No')
+                _(b're-merge all unresolved files (yn)?$$ &Yes $$ &No')
             ):
                 raise error.Abort(_(b'user quit'))
         if mark and not pats:
@@ -6474,7 +6472,7 @@ def serve(ui, repo, **opts):
     if opts[b"stdio"]:
         if repo is None:
             raise error.RepoError(
-                _(b"there is no Mercurial repository here" b" (.hg not found)")
+                _(b"there is no Mercurial repository here (.hg not found)")
             )
         s = wireprotoserver.sshserver(ui, repo)
         s.serve_forever()
@@ -7234,7 +7232,7 @@ def tag(ui, repo, name1, *names, **opts)
             scmutil.checknewlabel(repo, n, b'tag')
             if not n:
                 raise error.Abort(
-                    _(b'tag names cannot consist entirely of ' b'whitespace')
+                    _(b'tag names cannot consist entirely of whitespace')
                 )
         if opts.get(b'rev') and opts.get(b'remove'):
             raise error.Abort(_(b"--rev and --remove are incompatible"))
@@ -7269,7 +7267,7 @@ def tag(ui, repo, name1, *names, **opts)
             for n in names:
                 if n in repo.tags():
                     raise error.Abort(
-                        _(b"tag '%s' already exists " b"(use -f to force)") % n
+                        _(b"tag '%s' already exists (use -f to force)") % n
                     )
         if not opts.get(b'local'):
             p1, p2 = repo.dirstate.parents()
diff --git a/mercurial/context.py b/mercurial/context.py
--- a/mercurial/context.py
+++ b/mercurial/context.py
@@ -1619,7 +1619,7 @@ class workingctx(committablectx):
             return
         if not (stat.S_ISREG(st.st_mode) or stat.S_ISLNK(st.st_mode)):
             self._repo.ui.warn(
-                _(b"copy failed: %s is not a file or a " b"symbolic link\n")
+                _(b"copy failed: %s is not a file or a symbolic link\n")
                 % self._repo.dirstate.pathto(dest)
             )
         else:
@@ -1678,7 +1678,7 @@ class workingctx(committablectx):
                     or stringutil.binary(d)
                 ):
                     self._repo.ui.debug(
-                        b'ignoring suspect symlink placeholder' b' "%s"\n' % f
+                        b'ignoring suspect symlink placeholder "%s"\n' % f
                     )
                     continue
             sane.append(f)
@@ -1750,7 +1750,7 @@ class workingctx(committablectx):
                         # already changed simultaneously after last
                         # caching (see also issue5584 for detail)
                         self._repo.ui.debug(
-                            b'skip updating dirstate: ' b'identity mismatch\n'
+                            b'skip updating dirstate: identity mismatch\n'
                         )
             except error.LockError:
                 pass
diff --git a/mercurial/copies.py b/mercurial/copies.py
--- a/mercurial/copies.py
+++ b/mercurial/copies.py
@@ -677,7 +677,7 @@ def _fullcopytracing(repo, c1, c2, base)
                     if df not in copy:
                         movewithdir[f] = df
                         repo.ui.debug(
-                            (b"   pending file src: '%s' -> " b"dst: '%s'\n")
+                            b"   pending file src: '%s' -> dst: '%s'\n"
                             % (f, df)
                         )
                     break
diff --git a/mercurial/dagparser.py b/mercurial/dagparser.py
--- a/mercurial/dagparser.py
+++ b/mercurial/dagparser.py
@@ -275,7 +275,7 @@ def parsedag(desc):
                 i += 1
                 c = nextch()
             raise error.Abort(
-                _(b'invalid character in dag description: ' b'%s...') % s
+                _(b'invalid character in dag description: %s...') % s
             )
 
 
@@ -381,7 +381,7 @@ def dagtextlines(
                     yield b'\n'
                 else:
                     raise error.Abort(
-                        _(b"invalid event type in dag: " b"('%s', '%s')")
+                        _(b"invalid event type in dag: ('%s', '%s')")
                         % (
                             stringutil.escapestr(kind),
                             stringutil.escapestr(data),
diff --git a/mercurial/debugcommands.py b/mercurial/debugcommands.py
--- a/mercurial/debugcommands.py
+++ b/mercurial/debugcommands.py
@@ -109,7 +109,7 @@ def debugancestor(ui, repo, *args):
     elif len(args) == 2:
         if not repo:
             raise error.Abort(
-                _(b'there is no Mercurial repository here ' b'(.hg not found)')
+                _(b'there is no Mercurial repository here (.hg not found)')
             )
         rev1, rev2 = args
         r = repo.changelog
@@ -1464,7 +1464,7 @@ def debuginstall(ui, **opts):
     fm.condwrite(
         err,
         b'encodingerror',
-        _(b" %s\n" b" (check that your locale is properly set)\n"),
+        _(b" %s\n (check that your locale is properly set)\n"),
         err,
     )
 
@@ -1577,7 +1577,7 @@ def debuginstall(ui, **opts):
     )
     fm.write(
         b'compenginesavail',
-        _(b'checking available compression engines ' b'(%s)\n'),
+        _(b'checking available compression engines (%s)\n'),
         fm.formatlist(
             sorted(e.name() for e in compengines if e.available()),
             name=b'compengine',
@@ -1701,7 +1701,7 @@ def debuginstall(ui, **opts):
     fm.condwrite(
         problems,
         b'problems',
-        _(b"%d problems detected," b" please check your install!\n"),
+        _(b"%d problems detected, please check your install!\n"),
         problems,
     )
     fm.end()
@@ -2071,7 +2071,7 @@ def debugnamecomplete(ui, repo, *args):
             b'',
             b'exclusive',
             False,
-            _(b'restrict display to markers only ' b'relevant to REV'),
+            _(b'restrict display to markers only relevant to REV'),
         ),
         (b'', b'index', False, _(b'display index of the marker')),
         (b'', b'delete', [], _(b'delete markers specified by indices')),
@@ -2115,7 +2115,7 @@ def debugobsolete(ui, repo, precursor=No
 
         if repo.currenttransaction():
             raise error.Abort(
-                _(b'cannot delete obsmarkers in the middle ' b'of transaction.')
+                _(b'cannot delete obsmarkers in the middle of transaction.')
             )
 
         with repo.lock():
@@ -2949,7 +2949,7 @@ def debugrevlogindex(ui, repo, file_=Non
     if format == 0:
         if ui.verbose:
             ui.writenoi18n(
-                (b"   rev    offset  length linkrev" b" %s %s p2\n")
+                b"   rev    offset  length linkrev %s %s p2\n"
                 % (b"nodeid".ljust(idlen), b"p1".ljust(idlen))
             )
         else:
@@ -3096,7 +3096,7 @@ def debugrevspec(ui, repo, expr, **opts)
         stages = stages[:-1]
     if opts[b'verify_optimized'] and opts[b'no_optimized']:
         raise error.Abort(
-            _(b'cannot use --verify-optimized with ' b'--no-optimized')
+            _(b'cannot use --verify-optimized with --no-optimized')
         )
     stagenames = set(n for n, f in stages)
 
@@ -3276,7 +3276,7 @@ def debugssl(ui, repo, source=None, **op
     '''
     if not pycompat.iswindows:
         raise error.Abort(
-            _(b'certificate chain building is only possible on ' b'Windows')
+            _(b'certificate chain building is only possible on Windows')
         )
 
     if not source:
@@ -3422,7 +3422,7 @@ def debugtemplate(ui, repo, tmpl, **opts
     if opts[r'rev']:
         if repo is None:
             raise error.RepoError(
-                _(b'there is no Mercurial repository here ' b'(.hg not found)')
+                _(b'there is no Mercurial repository here (.hg not found)')
             )
         revs = scmutil.revrange(repo, opts[r'rev'])
 
@@ -3882,9 +3882,7 @@ def debugwireproto(ui, repo, path=None, 
         )
 
     if path and opts[b'localssh']:
-        raise error.Abort(
-            _(b'cannot specify --localssh with an explicit ' b'path')
-        )
+        raise error.Abort(_(b'cannot specify --localssh with an explicit path'))
 
     if ui.interactive():
         ui.write(_(b'(waiting for commands on stdin)\n'))
@@ -4153,7 +4151,7 @@ def debugwireproto(ui, repo, path=None, 
         elif action.startswith(b'httprequest '):
             if not opener:
                 raise error.Abort(
-                    _(b'cannot use httprequest without an HTTP ' b'peer')
+                    _(b'cannot use httprequest without an HTTP peer')
                 )
 
             request = action.split(b' ', 2)
diff --git a/mercurial/destutil.py b/mercurial/destutil.py
--- a/mercurial/destutil.py
+++ b/mercurial/destutil.py
@@ -129,9 +129,9 @@ def _destupdatebranchfallback(repo, clea
         heads = repo.branchheads(currentbranch, closed=True)
         assert heads, b"any branch has at least one head"
         node = repo.revs(b'max(.::(%ln))', heads).first()
-        assert node is not None, (
-            b"any revision has at least " b"one descendant branch head"
-        )
+        assert (
+            node is not None
+        ), b"any revision has at least one descendant branch head"
         if bookmarks.isactivewdirparent(repo):
             movemark = repo[b'.'].node()
     else:
diff --git a/mercurial/dirstate.py b/mercurial/dirstate.py
--- a/mercurial/dirstate.py
+++ b/mercurial/dirstate.py
@@ -467,7 +467,7 @@ class dirstate(object):
         '''Mark as coming from the other parent, always dirty.'''
         if self._pl[1] == nullid:
             raise error.Abort(
-                _(b"setting %r to other parent " b"only allowed in merges") % f
+                _(b"setting %r to other parent only allowed in merges") % f
             )
         if f in self and self[f] == b'n':
             # merge-like
@@ -1470,7 +1470,7 @@ class dirstatemap(object):
         if self._pendingmode is not None and self._pendingmode != mode:
             fp.close()
             raise error.Abort(
-                _(b'working directory state may be ' b'changed parallelly')
+                _(b'working directory state may be changed parallelly')
             )
         self._pendingmode = mode
         return fp
@@ -1494,7 +1494,7 @@ class dirstatemap(object):
                 self._parents = (nullid, nullid)
             else:
                 raise error.Abort(
-                    _(b'working directory state appears ' b'damaged!')
+                    _(b'working directory state appears damaged!')
                 )
 
         return self._parents
@@ -1671,7 +1671,7 @@ if rustmod is not None:
             if self._pendingmode is not None and self._pendingmode != mode:
                 fp.close()
                 raise error.Abort(
-                    _(b'working directory state may be ' b'changed parallelly')
+                    _(b'working directory state may be changed parallelly')
                 )
             self._pendingmode = mode
             return fp
@@ -1697,7 +1697,7 @@ if rustmod is not None:
                     self._parents = self._rustmap.parents(st)
                 except ValueError:
                     raise error.Abort(
-                        _(b'working directory state appears ' b'damaged!')
+                        _(b'working directory state appears damaged!')
                     )
 
             return self._parents
diff --git a/mercurial/discovery.py b/mercurial/discovery.py
--- a/mercurial/discovery.py
+++ b/mercurial/discovery.py
@@ -412,11 +412,11 @@ def checkheads(pushop):
                 heads = scmutil.nodesummaries(repo, unsyncedheads)
             if heads is None:
                 repo.ui.status(
-                    _(b"remote has heads that are " b"not known locally\n")
+                    _(b"remote has heads that are not known locally\n")
                 )
             elif branch is None:
                 repo.ui.status(
-                    _(b"remote has heads that are " b"not known locally: %s\n")
+                    _(b"remote has heads that are not known locally: %s\n")
                     % heads
                 )
             else:
@@ -447,7 +447,7 @@ def checkheads(pushop):
             if errormsg is None:
                 if branch not in (b'default', None):
                     errormsg = _(
-                        b"push creates new remote head %s " b"on branch '%s'!"
+                        b"push creates new remote head %s on branch '%s'!"
                     ) % (short(dhs[0]), branch)
                 elif repo[dhs[0]].bookmarks():
                     errormsg = _(
diff --git a/mercurial/dispatch.py b/mercurial/dispatch.py
--- a/mercurial/dispatch.py
+++ b/mercurial/dispatch.py
@@ -631,7 +631,7 @@ class cmdalias(object):
                 continue
             if not encoding.isasciistr(v):
                 self.badalias = _(
-                    b"non-ASCII character in alias definition " b"'%s:%s'"
+                    b"non-ASCII character in alias definition '%s:%s'"
                 ) % (name, k)
                 return
             cfg[k] = v
diff --git a/mercurial/exchange.py b/mercurial/exchange.py
--- a/mercurial/exchange.py
+++ b/mercurial/exchange.py
@@ -319,7 +319,7 @@ def getbundlespec(ui, fh):
                             b'a known bundlespec'
                         )
                         % version,
-                        hint=_(b'try upgrading your Mercurial ' b'client'),
+                        hint=_(b'try upgrading your Mercurial client'),
                     )
             elif part.type == b'stream2' and version is None:
                 # A stream2 part requires to be part of a v2 bundle
@@ -330,7 +330,7 @@ def getbundlespec(ui, fh):
 
         if not version:
             raise error.Abort(
-                _(b'could not identify changegroup version in ' b'bundle')
+                _(b'could not identify changegroup version in bundle')
             )
 
         return b'%s-%s' % (comp, version)
@@ -383,7 +383,7 @@ def _checkpublish(pushop):
             )
         elif behavior == b'confirm':
             if ui.promptchoice(
-                _(b'push and publish %i changesets (yn)?' b'$$ &Yes $$ &No')
+                _(b'push and publish %i changesets (yn)?$$ &Yes $$ &No')
                 % len(published)
             ):
                 raise error.Abort(_(b'user quit'))
@@ -1166,8 +1166,7 @@ def _abortonsecretctx(pushop, node, b):
     """abort if a given bookmark points to a secret changeset"""
     if node and pushop.repo[node].phase() == phases.secret:
         raise error.Abort(
-            _(b'cannot push bookmark %s as it points to a secret' b' changeset')
-            % b
+            _(b'cannot push bookmark %s as it points to a secret changeset') % b
         )
 
 
@@ -2696,7 +2695,7 @@ def check_heads(repo, their_heads, conte
         # someone else committed/pushed/unbundled while we
         # were transferring data
         raise error.PushRaced(
-            b'repository changed while %s - ' b'please try again' % context
+            b'repository changed while %s - please try again' % context
         )
 
 
@@ -2842,7 +2841,7 @@ def _maybeapplyclonebundle(pullop):
             )
         )
         repo.ui.warn(
-            _(b'(you may want to report this to the server ' b'operator)\n')
+            _(b'(you may want to report this to the server operator)\n')
         )
         return
 
diff --git a/mercurial/exchangev2.py b/mercurial/exchangev2.py
--- a/mercurial/exchangev2.py
+++ b/mercurial/exchangev2.py
@@ -219,7 +219,7 @@ def _fetchrawstorefiles(repo, remote):
                     vfs = repo.svfs
                 else:
                     raise error.Abort(
-                        _(b'invalid location for raw file data: ' b'%s')
+                        _(b'invalid location for raw file data: %s')
                         % filemeta[b'location']
                     )
 
diff --git a/mercurial/filemerge.py b/mercurial/filemerge.py
--- a/mercurial/filemerge.py
+++ b/mercurial/filemerge.py
@@ -315,7 +315,7 @@ def _iprompt(repo, mynode, orig, fcd, fc
     # conflicts.
     if fcd.changectx().isinmemory():
         raise error.InMemoryMergeConflictsError(
-            b'in-memory merge does not ' b'support file conflicts'
+            b'in-memory merge does not support file conflicts'
         )
 
     prompts = partextras(labels)
@@ -415,7 +415,7 @@ def _premerge(repo, fcd, fco, fca, toolc
         if premerge not in validkeep:
             _valid = b', '.join([b"'" + v + b"'" for v in validkeep])
             raise error.ConfigError(
-                _(b"%s.premerge not valid " b"('%s' is neither boolean nor %s)")
+                _(b"%s.premerge not valid ('%s' is neither boolean nor %s)")
                 % (tool, premerge, _valid)
             )
 
@@ -440,7 +440,7 @@ def _mergecheck(repo, mynode, orig, fcd,
     uipathfn = scmutil.getuipathfn(repo)
     if symlink:
         repo.ui.warn(
-            _(b'warning: internal %s cannot merge symlinks ' b'for %s\n')
+            _(b'warning: internal %s cannot merge symlinks for %s\n')
             % (tool, uipathfn(fcd.path()))
         )
         return False
@@ -606,7 +606,7 @@ def _idump(repo, mynode, orig, fcd, fco,
 
     if isinstance(fcd, context.overlayworkingfilectx):
         raise error.InMemoryMergeConflictsError(
-            b'in-memory merge does not ' b'support the :dump tool.'
+            b'in-memory merge does not support the :dump tool.'
         )
 
     util.writefile(a + b".local", fcd.decodeddata())
@@ -635,7 +635,7 @@ def _xmergeimm(repo, mynode, orig, fcd, 
     # directory and tell the user how to get it is my best idea, but it's
     # clunky.)
     raise error.InMemoryMergeConflictsError(
-        b'in-memory merge does not support ' b'external merge tools'
+        b'in-memory merge does not support external merge tools'
     )
 
 
@@ -698,7 +698,7 @@ def _xmerge(repo, mynode, orig, fcd, fco
     uipathfn = scmutil.getuipathfn(repo)
     if fcd.isabsent() or fco.isabsent():
         repo.ui.warn(
-            _(b'warning: %s cannot merge change/delete conflict ' b'for %s\n')
+            _(b'warning: %s cannot merge change/delete conflict for %s\n')
             % (tool, uipathfn(fcd.path()))
         )
         return False, 1, None
@@ -1064,7 +1064,7 @@ def _filemerge(premerge, repo, wctx, myn
         if onfailure:
             if wctx.isinmemory():
                 raise error.InMemoryMergeConflictsError(
-                    b'in-memory merge does ' b'not support merge ' b'conflicts'
+                    b'in-memory merge does not support merge conflicts'
                 )
             ui.warn(onfailure % fduipath)
         return True, 1, False
@@ -1150,7 +1150,7 @@ def _haltmerge():
 def _onfilemergefailure(ui):
     action = ui.config(b'merge', b'on-failure')
     if action == b'prompt':
-        msg = _(b'continue merge operation (yn)?' b'$$ &Yes $$ &No')
+        msg = _(b'continue merge operation (yn)?$$ &Yes $$ &No')
         if ui.promptchoice(msg, 0) == 1:
             _haltmerge()
     if action == b'halt':
@@ -1180,7 +1180,7 @@ def _check(repo, r, ui, tool, fcd, files
     if b'prompt' in _toollist(ui, tool, b"check"):
         checked = True
         if ui.promptchoice(
-            _(b"was merge of '%s' successful (yn)?" b"$$ &Yes $$ &No")
+            _(b"was merge of '%s' successful (yn)?$$ &Yes $$ &No")
             % uipathfn(fd),
             1,
         ):
diff --git a/mercurial/help.py b/mercurial/help.py
--- a/mercurial/help.py
+++ b/mercurial/help.py
@@ -860,7 +860,7 @@ def help_(
             )
             if name == b'shortlist':
                 rst.append(
-                    _(b"\n(use 'hg help' for the full list " b"of commands)\n")
+                    _(b"\n(use 'hg help' for the full list of commands)\n")
                 )
         else:
             if name == b'shortlist':
@@ -872,7 +872,7 @@ def help_(
                 )
             elif name and not full:
                 rst.append(
-                    _(b"\n(use 'hg help %s' to show the full help " b"text)\n")
+                    _(b"\n(use 'hg help %s' to show the full help text)\n")
                     % name
                 )
             elif name and syns and name in syns.keys():
@@ -929,7 +929,7 @@ def help_(
         try:
             cmdutil.findcmd(name, commands.table)
             rst.append(
-                _(b"\nuse 'hg help -c %s' to see help for " b"the %s command\n")
+                _(b"\nuse 'hg help -c %s' to see help for the %s command\n")
                 % (name, name)
             )
         except error.UnknownCommand:
@@ -985,7 +985,7 @@ def help_(
         doc = doc.splitlines()[0]
 
         rst = listexts(
-            _(b"'%s' is provided by the following " b"extension:") % cmd,
+            _(b"'%s' is provided by the following extension:") % cmd,
             {ext: doc},
             indent=4,
             showdeprecated=True,
diff --git a/mercurial/hg.py b/mercurial/hg.py
--- a/mercurial/hg.py
+++ b/mercurial/hg.py
@@ -379,7 +379,7 @@ def postshare(sourcerepo, destrepo, defa
     """
     default = defaultpath or sourcerepo.ui.config(b'paths', b'default')
     if default:
-        template = b'[paths]\n' b'default = %s\n'
+        template = b'[paths]\ndefault = %s\n'
         destrepo.vfs.write(b'hgrc', util.tonativeeol(template % default))
     if repositorymod.NARROW_REQUIREMENT in sourcerepo.requirements:
         with destrepo.wlock():
@@ -1182,9 +1182,7 @@ def abortmerge(ui, repo):
         # there were no conficts, mergestate was not stored
         node = repo[b'.'].hex()
 
-    repo.ui.status(
-        _(b"aborting the merge, updating back to" b" %s\n") % node[:12]
-    )
+    repo.ui.status(_(b"aborting the merge, updating back to %s\n") % node[:12])
     stats = mergemod.update(repo, node, branchmerge=False, force=True)
     _showstats(repo, stats)
     return stats.unresolvedcount > 0
diff --git a/mercurial/hgweb/__init__.py b/mercurial/hgweb/__init__.py
--- a/mercurial/hgweb/__init__.py
+++ b/mercurial/hgweb/__init__.py
@@ -119,6 +119,6 @@ def createapp(baseui, repo, webconf):
     else:
         if not repo:
             raise error.RepoError(
-                _(b"there is no Mercurial repository" b" here (.hg not found)")
+                _(b"there is no Mercurial repository here (.hg not found)")
             )
         return hgweb_mod.hgweb(repo, baseui=baseui)
diff --git a/mercurial/hgweb/request.py b/mercurial/hgweb/request.py
--- a/mercurial/hgweb/request.py
+++ b/mercurial/hgweb/request.py
@@ -516,7 +516,7 @@ class wsgiresponse(object):
 
             if self._bodygen is not None or self._bodywillwrite:
                 raise error.ProgrammingError(
-                    b"must use setbodybytes('') with " b"304 responses"
+                    b"must use setbodybytes('') with 304 responses"
                 )
 
         # Various HTTP clients (notably httplib) won't read the HTTP response
diff --git a/mercurial/hgweb/server.py b/mercurial/hgweb/server.py
--- a/mercurial/hgweb/server.py
+++ b/mercurial/hgweb/server.py
@@ -242,7 +242,7 @@ class _httprequesthandler(httpservermod.
     def send_headers(self):
         if not self.saved_status:
             raise AssertionError(
-                b"Sending headers before " b"start_response() called"
+                b"Sending headers before start_response() called"
             )
         saved_status = self.saved_status.split(None, 1)
         saved_status[0] = int(saved_status[0])
diff --git a/mercurial/hgweb/webcommands.py b/mercurial/hgweb/webcommands.py
--- a/mercurial/hgweb/webcommands.py
+++ b/mercurial/hgweb/webcommands.py
@@ -1295,7 +1295,7 @@ def archive(web):
     web.res.setbodywillwrite()
     if list(web.res.sendresponse()):
         raise error.ProgrammingError(
-            b'sendresponse() should not emit data ' b'if writing later'
+            b'sendresponse() should not emit data if writing later'
         )
 
     bodyfh = web.res.getbodyfile()
diff --git a/mercurial/hook.py b/mercurial/hook.py
--- a/mercurial/hook.py
+++ b/mercurial/hook.py
@@ -117,7 +117,7 @@ def pythonhook(ui, repo, htype, hname, f
             ui.warn(_(b'error: %s hook failed: %s\n') % (hname, exc.args[0]))
         else:
             ui.warn(
-                _(b'error: %s hook raised an exception: ' b'%s\n')
+                _(b'error: %s hook raised an exception: %s\n')
                 % (hname, stringutil.forcebytestr(exc))
             )
         if throw:
diff --git a/mercurial/httppeer.py b/mercurial/httppeer.py
--- a/mercurial/httppeer.py
+++ b/mercurial/httppeer.py
@@ -383,14 +383,13 @@ def parsev1commandresponse(
                 return respurl, proto, resp
             else:
                 raise error.RepoError(
-                    _(b'unexpected CBOR response from ' b'server')
+                    _(b'unexpected CBOR response from server')
                 )
 
         version_info = tuple([int(n) for n in subtype.split(b'.')])
     except ValueError:
         raise error.RepoError(
-            _(b"'%s' sent a broken Content-Type " b"header (%s)")
-            % (safeurl, proto)
+            _(b"'%s' sent a broken Content-Type header (%s)") % (safeurl, proto)
         )
 
     # TODO consider switching to a decompression reader that uses
@@ -685,12 +684,12 @@ class httpv2executor(object):
     def callcommand(self, command, args):
         if self._sent:
             raise error.ProgrammingError(
-                b'callcommand() cannot be used after ' b'commands are sent'
+                b'callcommand() cannot be used after commands are sent'
             )
 
         if self._closed:
             raise error.ProgrammingError(
-                b'callcommand() cannot be used after ' b'close()'
+                b'callcommand() cannot be used after close()'
             )
 
         # The service advertises which commands are available. So if we attempt
@@ -763,7 +762,7 @@ class httpv2executor(object):
 
         if len(permissions) > 1:
             raise error.RepoError(
-                _(b'cannot make request requiring multiple ' b'permissions: %s')
+                _(b'cannot make request requiring multiple permissions: %s')
                 % _(b', ').join(sorted(permissions))
             )
 
@@ -1101,7 +1100,7 @@ def instance(ui, path, create, intents=N
     try:
         if path.startswith(b'https:') and not urlmod.has_https:
             raise error.Abort(
-                _(b'Python support for SSL and HTTPS ' b'is not installed')
+                _(b'Python support for SSL and HTTPS is not installed')
             )
 
         inst = makepeer(ui, path)
diff --git a/mercurial/keepalive.py b/mercurial/keepalive.py
--- a/mercurial/keepalive.py
+++ b/mercurial/keepalive.py
@@ -296,7 +296,7 @@ class KeepAliveHandler(object):
             # a DIFFERENT exception
             if DEBUG:
                 DEBUG.error(
-                    b"unexpected exception - closing " b"connection to %s (%d)",
+                    b"unexpected exception - closing connection to %s (%d)",
                     host,
                     id(h),
                 )
diff --git a/mercurial/localrepo.py b/mercurial/localrepo.py
--- a/mercurial/localrepo.py
+++ b/mercurial/localrepo.py
@@ -223,12 +223,12 @@ class localcommandexecutor(object):
     def callcommand(self, command, args):
         if self._sent:
             raise error.ProgrammingError(
-                b'callcommand() cannot be used after ' b'sendcommands()'
+                b'callcommand() cannot be used after sendcommands()'
             )
 
         if self._closed:
             raise error.ProgrammingError(
-                b'callcommand() cannot be used after ' b'close()'
+                b'callcommand() cannot be used after close()'
             )
 
         # We don't need to support anything fancy. Just call the named
@@ -343,9 +343,7 @@ class localpeer(repository.peer):
         return self._repo.pushkey(namespace, key, old, new)
 
     def stream_out(self):
-        raise error.Abort(
-            _(b'cannot perform stream clone against local ' b'peer')
-        )
+        raise error.Abort(_(b'cannot perform stream clone against local peer'))
 
     def unbundle(self, bundle, heads, url):
         """apply a bundle on a repo
@@ -568,7 +566,7 @@ def makelocalrepository(baseui, path, in
 
         if not sharedvfs.exists():
             raise error.RepoError(
-                _(b'.hg/sharedpath points to nonexistent ' b'directory %s')
+                _(b'.hg/sharedpath points to nonexistent directory %s')
                 % sharedvfs.base
             )
 
@@ -1453,7 +1451,7 @@ class localrepository(object):
             if not self._dirstatevalidatewarned:
                 self._dirstatevalidatewarned = True
                 self.ui.warn(
-                    _(b"warning: ignoring unknown" b" working parent %s!\n")
+                    _(b"warning: ignoring unknown working parent %s!\n")
                     % short(node)
                 )
             return nullid
@@ -2302,7 +2300,7 @@ class localrepository(object):
                 ) % (oldtip, desc, detail)
             else:
                 msg = _(
-                    b'repository tip rolled back to revision %d' b' (undo %s)\n'
+                    b'repository tip rolled back to revision %d (undo %s)\n'
                 ) % (oldtip, desc)
         except IOError:
             msg = _(b'rolling back unknown transaction\n')
@@ -2367,8 +2365,7 @@ class localrepository(object):
                 )
             else:
                 ui.status(
-                    _(b'working directory now based on ' b'revision %d\n')
-                    % parents
+                    _(b'working directory now based on revision %d\n') % parents
                 )
             mergemod.mergestate.clean(self, self[b'.'].node())
 
@@ -3600,7 +3597,7 @@ def createrepository(ui, path, createopt
 
     if not isinstance(unknownopts, dict):
         raise error.ProgrammingError(
-            b'filterknowncreateopts() did not return ' b'a dict'
+            b'filterknowncreateopts() did not return a dict'
         )
 
     if unknownopts:
@@ -3687,7 +3684,7 @@ def poisonrepository(repo):
                 return object.__getattribute__(self, item)
 
             raise error.ProgrammingError(
-                b'repo instances should not be used ' b'after unshare'
+                b'repo instances should not be used after unshare'
             )
 
         def close(self):
diff --git a/mercurial/logcmdutil.py b/mercurial/logcmdutil.py
--- a/mercurial/logcmdutil.py
+++ b/mercurial/logcmdutil.py
@@ -925,8 +925,7 @@ def getlinerangerevs(repo, userrevs, opt
     for fname, (fromline, toline) in _parselinerangeopt(repo, opts):
         if fname not in wctx:
             raise error.Abort(
-                _(b'cannot follow file not in parent ' b'revision: "%s"')
-                % fname
+                _(b'cannot follow file not in parent revision: "%s"') % fname
             )
         fctx = wctx.filectx(fname)
         for fctx, linerange in dagop.blockancestors(fctx, fromline, toline):
diff --git a/mercurial/mail.py b/mercurial/mail.py
--- a/mercurial/mail.py
+++ b/mercurial/mail.py
@@ -236,8 +236,7 @@ def validateconfig(ui):
     else:
         if not procutil.findexe(method):
             raise error.Abort(
-                _(b'%r specified as email transport, ' b'but not in PATH')
-                % method
+                _(b'%r specified as email transport, but not in PATH') % method
             )
 
 
diff --git a/mercurial/manifest.py b/mercurial/manifest.py
--- a/mercurial/manifest.py
+++ b/mercurial/manifest.py
@@ -778,7 +778,7 @@ class treemanifest(object):
 
             def readsubtree(subdir, subm):
                 raise AssertionError(
-                    b'treemanifest constructor only accepts ' b'flat manifests'
+                    b'treemanifest constructor only accepts flat manifests'
                 )
 
             self.parse(text, readsubtree)
diff --git a/mercurial/match.py b/mercurial/match.py
--- a/mercurial/match.py
+++ b/mercurial/match.py
@@ -66,7 +66,7 @@ def _expandsets(kindpats, ctx=None, list
         if kind == b'set':
             if ctx is None:
                 raise error.ProgrammingError(
-                    b"fileset expression with no " b"context"
+                    b"fileset expression with no context"
                 )
             matchers.append(ctx.matchfileset(pat, badfn=badfn))
 
@@ -546,7 +546,7 @@ class predicatematcher(basematcher):
 def normalizerootdir(dir, funcname):
     if dir == b'.':
         util.nouideprecwarn(
-            b"match.%s() no longer accepts " b"'.', use '' instead." % funcname,
+            b"match.%s() no longer accepts '.', use '' instead." % funcname,
             b'5.1',
         )
         return b''
diff --git a/mercurial/mdiff.py b/mercurial/mdiff.py
--- a/mercurial/mdiff.py
+++ b/mercurial/mdiff.py
@@ -83,7 +83,7 @@ class diffopts(object):
             self.context = int(self.context)
         except ValueError:
             raise error.Abort(
-                _(b'diff context lines count must be ' b'an integer, not %r')
+                _(b'diff context lines count must be an integer, not %r')
                 % pycompat.bytestr(self.context)
             )
 
diff --git a/mercurial/merge.py b/mercurial/merge.py
--- a/mercurial/merge.py
+++ b/mercurial/merge.py
@@ -760,7 +760,7 @@ def _getcheckunknownconfig(repo, section
     if config not in valid:
         validstr = b', '.join([b"'" + v + b"'" for v in valid])
         raise error.ConfigError(
-            _(b"%s.%s not valid " b"('%s' is none of %s)")
+            _(b"%s.%s not valid ('%s' is none of %s)")
             % (section, name, config, validstr)
         )
     return config
@@ -1048,7 +1048,7 @@ def _checkcollision(repo, wmf, actions):
         if fold.startswith(foldprefix) and not f.startswith(unfoldprefix):
             # the folded prefix matches but actual casing is different
             raise error.Abort(
-                _(b"case-folding collision between " b"%s and directory of %s")
+                _(b"case-folding collision between %s and directory of %s")
                 % (lastfull, f)
             )
         foldprefix = fold + b'/'
@@ -1225,11 +1225,11 @@ def _filternarrowactions(narrowmatch, br
                     b'which is not yet supported'
                 )
                 % f,
-                hint=_(b'merging in the other direction ' b'may work'),
+                hint=_(b'merging in the other direction may work'),
             )
         else:
             raise error.Abort(
-                _(b'conflict in file \'%s\' is outside ' b'narrow clone') % f
+                _(b'conflict in file \'%s\' is outside narrow clone') % f
             )
 
 
@@ -1992,7 +1992,7 @@ def applyupdates(
     if usemergedriver:
         if wctx.isinmemory():
             raise error.InMemoryMergeConflictsError(
-                b"in-memory merge does not " b"support mergedriver"
+                b"in-memory merge does not support mergedriver"
             )
         ms.commit()
         proceed = driverpreprocess(repo, ms, wctx, labels=labels)
@@ -2334,7 +2334,7 @@ def update(
                 if not mergeancestor and wc.branch() == p2.branch():
                     raise error.Abort(
                         _(b"nothing to merge"),
-                        hint=_(b"use 'hg update' " b"or check 'hg heads'"),
+                        hint=_(b"use 'hg update' or check 'hg heads'"),
                     )
             if not force and (wc.files() or wc.deleted()):
                 raise error.Abort(
diff --git a/mercurial/mergeutil.py b/mercurial/mergeutil.py
--- a/mercurial/mergeutil.py
+++ b/mercurial/mergeutil.py
@@ -15,7 +15,7 @@ from . import error
 def checkunresolved(ms):
     if list(ms.unresolved()):
         raise error.Abort(
-            _(b"unresolved merge conflicts " b"(see 'hg help resolve')")
+            _(b"unresolved merge conflicts (see 'hg help resolve')")
         )
     if ms.mdstate() != b's' or list(ms.driverresolved()):
         raise error.Abort(
diff --git a/mercurial/narrowspec.py b/mercurial/narrowspec.py
--- a/mercurial/narrowspec.py
+++ b/mercurial/narrowspec.py
@@ -110,7 +110,7 @@ def validatepatterns(pats):
     """
     if not isinstance(pats, set):
         raise error.ProgrammingError(
-            b'narrow patterns should be a set; ' b'got %r' % pats
+            b'narrow patterns should be a set; got %r' % pats
         )
 
     for pat in pats:
diff --git a/mercurial/obsolete.py b/mercurial/obsolete.py
--- a/mercurial/obsolete.py
+++ b/mercurial/obsolete.py
@@ -667,7 +667,7 @@ class obsstore(object):
         Return the number of new marker."""
         if self._readonly:
             raise error.Abort(
-                _(b'creating obsolete markers is not enabled on ' b'this repo')
+                _(b'creating obsolete markers is not enabled on this repo')
             )
         known = set()
         getsuccessors = self.successors.get
diff --git a/mercurial/obsutil.py b/mercurial/obsutil.py
--- a/mercurial/obsutil.py
+++ b/mercurial/obsutil.py
@@ -929,7 +929,7 @@ filteredmsgtable = {
     b"superseded": _(b"hidden revision '%s' was rewritten as: %s"),
     b"superseded_split": _(b"hidden revision '%s' was split as: %s"),
     b"superseded_split_several": _(
-        b"hidden revision '%s' was split as: %s and " b"%d more"
+        b"hidden revision '%s' was split as: %s and %d more"
     ),
 }
 
diff --git a/mercurial/parser.py b/mercurial/parser.py
--- a/mercurial/parser.py
+++ b/mercurial/parser.py
@@ -163,12 +163,12 @@ def buildargsdict(trees, funcname, argsp
     )
     if kwstart < len(poskeys):
         raise error.ParseError(
-            _(b"%(func)s takes at least %(nargs)d positional " b"arguments")
+            _(b"%(func)s takes at least %(nargs)d positional arguments")
             % {b'func': funcname, b'nargs': len(poskeys)}
         )
     if not varkey and kwstart > len(poskeys) + len(keys):
         raise error.ParseError(
-            _(b"%(func)s takes at most %(nargs)d positional " b"arguments")
+            _(b"%(func)s takes at most %(nargs)d positional arguments")
             % {b'func': funcname, b'nargs': len(poskeys) + len(keys)}
         )
     args = util.sortdict()
@@ -193,7 +193,7 @@ def buildargsdict(trees, funcname, argsp
             d = args
         elif not optkey:
             raise error.ParseError(
-                _(b"%(func)s got an unexpected keyword " b"argument '%(key)s'")
+                _(b"%(func)s got an unexpected keyword argument '%(key)s'")
                 % {b'func': funcname, b'key': k}
             )
         else:
@@ -713,7 +713,7 @@ class basealiasrules(object):
             raise error.Abort(a.error)
         if a in expanding:
             raise error.ParseError(
-                _(b'infinite expansion of %(section)s ' b'"%(name)s" detected')
+                _(b'infinite expansion of %(section)s "%(name)s" detected')
                 % {b'section': cls._section, b'name': a.name}
             )
         # get cacheable replacement tree by expanding aliases recursively
diff --git a/mercurial/patch.py b/mercurial/patch.py
--- a/mercurial/patch.py
+++ b/mercurial/patch.py
@@ -51,7 +51,7 @@ stringio = util.stringio
 gitre = re.compile(br'diff --git a/(.*) b/(.*)')
 tabsplitter = re.compile(br'(\t+|[^\t]+)')
 wordsplitter = re.compile(
-    br'(\t+| +|[a-zA-Z0-9_\x80-\xff]+|' b'[^ \ta-zA-Z0-9_\x80-\xff])'
+    br'(\t+| +|[a-zA-Z0-9_\x80-\xff]+|[^ \ta-zA-Z0-9_\x80-\xff])'
 )
 
 PatchError = error.PatchError
@@ -805,7 +805,7 @@ class patchfile(object):
         if self.exists and self.create:
             if self.copysource:
                 self.ui.warn(
-                    _(b"cannot create %s: destination already " b"exists\n")
+                    _(b"cannot create %s: destination already exists\n")
                     % self.fname
                 )
             else:
@@ -3191,7 +3191,7 @@ def diffstat(lines, width=80):
 
     if stats:
         output.append(
-            _(b' %d files changed, %d insertions(+), ' b'%d deletions(-)\n')
+            _(b' %d files changed, %d insertions(+), %d deletions(-)\n')
             % (len(stats), totaladds, totalremoves)
         )
 
diff --git a/mercurial/profiling.py b/mercurial/profiling.py
--- a/mercurial/profiling.py
+++ b/mercurial/profiling.py
@@ -43,9 +43,7 @@ def lsprofile(ui, fp):
     climit = ui.configint(b'profiling', b'nested')
 
     if format not in [b'text', b'kcachegrind']:
-        ui.warn(
-            _(b"unrecognized profiling format '%s'" b" - Ignored\n") % format
-        )
+        ui.warn(_(b"unrecognized profiling format '%s' - Ignored\n") % format)
         format = b'text'
 
     try:
diff --git a/mercurial/pycompat.py b/mercurial/pycompat.py
--- a/mercurial/pycompat.py
+++ b/mercurial/pycompat.py
@@ -361,7 +361,7 @@ else:
     setattr = setattr
 
     # this can't be parsed on Python 3
-    exec(b'def raisewithtb(exc, tb):\n' b'    raise exc, None, tb\n')
+    exec(b'def raisewithtb(exc, tb):\n    raise exc, None, tb\n')
 
     def fsencode(filename):
         """
diff --git a/mercurial/repair.py b/mercurial/repair.py
--- a/mercurial/repair.py
+++ b/mercurial/repair.py
@@ -359,7 +359,7 @@ def safestriproots(ui, repo, nodes):
     if notstrip:
         nodestr = b', '.join(sorted(short(repo[n].node()) for n in notstrip))
         ui.warn(
-            _(b'warning: orphaned descendants detected, ' b'not stripping %s\n')
+            _(b'warning: orphaned descendants detected, not stripping %s\n')
             % nodestr
         )
     return [c.node() for c in repo.set(b'roots(%ld)', tostrip)]
diff --git a/mercurial/repocache.py b/mercurial/repocache.py
--- a/mercurial/repocache.py
+++ b/mercurial/repocache.py
@@ -70,7 +70,7 @@ class repoloader(object):
         """
         if self._thread and self._thread.is_alive():
             raise error.ProgrammingError(
-                b'cannot obtain cached repo while ' b'loader is active'
+                b'cannot obtain cached repo while loader is active'
             )
         return self._cache.peek(path, None)
 
diff --git a/mercurial/revlog.py b/mercurial/revlog.py
--- a/mercurial/revlog.py
+++ b/mercurial/revlog.py
@@ -244,7 +244,7 @@ class revlogoldio(object):
     def packentry(self, entry, node, version, rev):
         if gettype(entry[0]):
             raise error.RevlogError(
-                _(b'index entry flags need revlog ' b'version 1')
+                _(b'index entry flags need revlog version 1')
             )
         e2 = (
             getoffset(entry[0]),
@@ -451,12 +451,12 @@ class revlog(object):
 
         if self._chunkcachesize <= 0:
             raise error.RevlogError(
-                _(b'revlog chunk cache size %r is not ' b'greater than 0')
+                _(b'revlog chunk cache size %r is not greater than 0')
                 % self._chunkcachesize
             )
         elif self._chunkcachesize & (self._chunkcachesize - 1):
             raise error.RevlogError(
-                _(b'revlog chunk cache size %r is not a ' b'power of 2')
+                _(b'revlog chunk cache size %r is not a power of 2')
                 % self._chunkcachesize
             )
 
@@ -492,7 +492,7 @@ class revlog(object):
         if fmt == REVLOGV0:
             if flags:
                 raise error.RevlogError(
-                    _(b'unknown flags (%#04x) in version %d ' b'revlog %s')
+                    _(b'unknown flags (%#04x) in version %d revlog %s')
                     % (flags >> 16, fmt, self.indexfile)
                 )
 
@@ -502,7 +502,7 @@ class revlog(object):
         elif fmt == REVLOGV1:
             if flags & ~REVLOGV1_FLAGS:
                 raise error.RevlogError(
-                    _(b'unknown flags (%#04x) in version %d ' b'revlog %s')
+                    _(b'unknown flags (%#04x) in version %d revlog %s')
                     % (flags >> 16, fmt, self.indexfile)
                 )
 
@@ -512,7 +512,7 @@ class revlog(object):
         elif fmt == REVLOGV2:
             if flags & ~REVLOGV2_FLAGS:
                 raise error.RevlogError(
-                    _(b'unknown flags (%#04x) in version %d ' b'revlog %s')
+                    _(b'unknown flags (%#04x) in version %d revlog %s')
                     % (flags >> 16, fmt, self.indexfile)
                 )
 
@@ -2707,7 +2707,7 @@ class revlog(object):
 
         if len(tombstone) > self.rawsize(censorrev):
             raise error.Abort(
-                _(b'censor tombstone must be no longer than ' b'censored data')
+                _(b'censor tombstone must be no longer than censored data')
             )
 
         # Rewriting the revlog in place is hard. Our strategy for censoring is
diff --git a/mercurial/revset.py b/mercurial/revset.py
--- a/mercurial/revset.py
+++ b/mercurial/revset.py
@@ -980,7 +980,7 @@ def expectsize(repo, subset, x, order):
         raise error.ParseError(_(b'invalid set of arguments'))
     minsize, maxsize = getintrange(
         args[b'size'],
-        _(b'expectsize requires a size range' b' or a positive integer'),
+        _(b'expectsize requires a size range or a positive integer'),
         _(b'size range bounds must be integers'),
         minsize,
         maxsize,
@@ -989,11 +989,13 @@ def expectsize(repo, subset, x, order):
         raise error.ParseError(_(b'negative size'))
     rev = getset(repo, fullreposet(repo), args[b'set'], order=order)
     if minsize != maxsize and (len(rev) < minsize or len(rev) > maxsize):
-        err = _(
-            b'revset size mismatch.' b' expected between %d and %d, got %d'
-        ) % (minsize, maxsize, len(rev))
+        err = _(b'revset size mismatch. expected between %d and %d, got %d') % (
+            minsize,
+            maxsize,
+            len(rev),
+        )
     elif minsize == maxsize and len(rev) != minsize:
-        err = _(b'revset size mismatch.' b' expected %d, got %d') % (
+        err = _(b'revset size mismatch. expected %d, got %d') % (
             minsize,
             len(rev),
         )
@@ -1043,14 +1045,14 @@ def extra(repo, subset, x):
         raise error.ParseError(_(b'extra takes at least 1 argument'))
     # i18n: "extra" is a keyword
     label = getstring(
-        args[b'label'], _(b'first argument to extra must be ' b'a string')
+        args[b'label'], _(b'first argument to extra must be a string')
     )
     value = None
 
     if b'value' in args:
         # i18n: "extra" is a keyword
         value = getstring(
-            args[b'value'], _(b'second argument to extra must be ' b'a string')
+            args[b'value'], _(b'second argument to extra must be a string')
         )
         kind, value, matcher = stringutil.stringmatcher(value)
 
@@ -1314,7 +1316,7 @@ def _matchfiles(repo, subset, x):
         elif prefix == b'r:':
             if rev is not None:
                 raise error.ParseError(
-                    b'_matchfiles expected at most one ' b'revision'
+                    b'_matchfiles expected at most one revision'
                 )
             if value == b'':  # empty means working directory
                 rev = node.wdirrev
@@ -1323,7 +1325,7 @@ def _matchfiles(repo, subset, x):
         elif prefix == b'd:':
             if default is not None:
                 raise error.ParseError(
-                    b'_matchfiles expected at most one ' b'default mode'
+                    b'_matchfiles expected at most one default mode'
                 )
             default = value
         else:
@@ -2127,7 +2129,7 @@ def matching(repo, subset, x):
         fieldlist = getstring(
             l[1],
             # i18n: "matching" is a keyword
-            _(b"matching requires a string " b"as its second argument"),
+            _(b"matching requires a string as its second argument"),
         ).split()
 
     # Make sure that there are no repeated fields,
@@ -2284,7 +2286,7 @@ def _getsortargs(x):
     if len(keyflags) > 1 and any(k == b'topo' for k, reverse in keyflags):
         # i18n: "topo" is a keyword
         raise error.ParseError(
-            _(b'topo sort order cannot be combined ' b'with other sort keys')
+            _(b'topo sort order cannot be combined with other sort keys')
         )
 
     opts = {}
diff --git a/mercurial/shelve.py b/mercurial/shelve.py
--- a/mercurial/shelve.py
+++ b/mercurial/shelve.py
@@ -456,7 +456,7 @@ def _nothingtoshelvemessaging(ui, repo, 
     stat = repo.status(match=scmutil.match(repo[None], pats, opts))
     if stat.deleted:
         ui.status(
-            _(b"nothing changed (%d missing files, see " b"'hg status')\n")
+            _(b"nothing changed (%d missing files, see 'hg status')\n")
             % len(stat.deleted)
         )
     else:
@@ -707,7 +707,7 @@ def checkparents(repo, state):
     """check parent while resuming an unshelve"""
     if state.parents != repo.dirstate.parents():
         raise error.Abort(
-            _(b'working directory parents do not match unshelve ' b'state')
+            _(b'working directory parents do not match unshelve state')
         )
 
 
diff --git a/mercurial/sparse.py b/mercurial/sparse.py
--- a/mercurial/sparse.py
+++ b/mercurial/sparse.py
@@ -121,7 +121,7 @@ def patternsforrev(repo, rev):
 
     if rev is None:
         raise error.Abort(
-            _(b'cannot parse sparse patterns from working ' b'directory')
+            _(b'cannot parse sparse patterns from working directory')
         )
 
     includes, excludes, profiles = parseconfig(repo.ui, raw, b'sparse')
@@ -483,7 +483,7 @@ def refreshwdir(repo, origstatus, origsp
 
     if abort:
         raise error.Abort(
-            _(b'could not update sparseness due to pending ' b'changes')
+            _(b'could not update sparseness due to pending changes')
         )
 
     # Calculate actions
diff --git a/mercurial/sslutil.py b/mercurial/sslutil.py
--- a/mercurial/sslutil.py
+++ b/mercurial/sslutil.py
@@ -210,7 +210,7 @@ def _hostsettings(ui, hostname):
         if not (fingerprint.startswith((b'sha1:', b'sha256:', b'sha512:'))):
             raise error.Abort(
                 _(b'invalid fingerprint for %s: %s') % (bhostname, fingerprint),
-                hint=_(b'must begin with "sha1:", "sha256:", ' b'or "sha512:"'),
+                hint=_(b'must begin with "sha1:", "sha256:", or "sha512:"'),
             )
 
         alg, fingerprint = fingerprint.split(b':', 1)
@@ -328,7 +328,7 @@ def protocolsettings(protocol):
     if supportedprotocols == {b'tls1.0'}:
         if protocol != b'tls1.0':
             raise error.Abort(
-                _(b'current Python does not support protocol ' b'setting %s')
+                _(b'current Python does not support protocol setting %s')
                 % protocol,
                 hint=_(
                     b'upgrade Python or disable setting since '
@@ -616,7 +616,7 @@ def wrapserversocket(
     for f in (certfile, keyfile, cafile):
         if f and not os.path.exists(f):
             raise error.Abort(
-                _(b'referenced certificate file (%s) does not ' b'exist') % f
+                _(b'referenced certificate file (%s) does not exist') % f
             )
 
     protocol, options, _protocolui = protocolsettings(b'tls1.0')
@@ -928,7 +928,7 @@ def validatesocket(sock):
 
     if not peercert:
         raise error.Abort(
-            _(b'%s certificate error: ' b'no certificate received') % host
+            _(b'%s certificate error: no certificate received') % host
         )
 
     if settings[b'disablecertverification']:
@@ -990,7 +990,7 @@ def validatesocket(sock):
             section = b'hostsecurity'
             nice = b'%s:%s' % (hash, fmtfingerprint(peerfingerprints[hash]))
         raise error.Abort(
-            _(b'certificate for %s has unexpected ' b'fingerprint %s')
+            _(b'certificate for %s has unexpected fingerprint %s')
             % (host, nice),
             hint=_(b'check %s configuration') % section,
         )
diff --git a/mercurial/state.py b/mercurial/state.py
--- a/mercurial/state.py
+++ b/mercurial/state.py
@@ -60,7 +60,7 @@ class cmdstate(object):
         """
         if not isinstance(version, int):
             raise error.ProgrammingError(
-                b"version of state file should be" b" an integer"
+                b"version of state file should be an integer"
             )
 
         with self._repo.vfs(self.fname, b'wb', atomictemp=True) as fp:
@@ -76,7 +76,7 @@ class cmdstate(object):
                 int(fp.readline())
             except ValueError:
                 raise error.CorruptedState(
-                    b"unknown version of state file" b" found"
+                    b"unknown version of state file found"
                 )
 
             return cborutil.decodeall(fp.read())[0]
diff --git a/mercurial/streamclone.py b/mercurial/streamclone.py
--- a/mercurial/streamclone.py
+++ b/mercurial/streamclone.py
@@ -468,14 +468,14 @@ def applybundlev1(repo, fp):
     """
     if len(repo):
         raise error.Abort(
-            _(b'cannot apply stream clone bundle on non-empty ' b'repo')
+            _(b'cannot apply stream clone bundle on non-empty repo')
         )
 
     filecount, bytecount, requirements = readbundle1header(fp)
     missingreqs = requirements - repo.supportedformats
     if missingreqs:
         raise error.Abort(
-            _(b'unable to apply stream clone: ' b'unsupported format: %s')
+            _(b'unable to apply stream clone: unsupported format: %s')
             % b', '.join(sorted(missingreqs))
         )
 
@@ -715,7 +715,7 @@ def applybundlev2(repo, fp, filecount, f
     missingreqs = [r for r in requirements if r not in repo.supported]
     if missingreqs:
         raise error.Abort(
-            _(b'unable to apply stream clone: ' b'unsupported format: %s')
+            _(b'unable to apply stream clone: unsupported format: %s')
             % b', '.join(sorted(missingreqs))
         )
 
diff --git a/mercurial/subrepo.py b/mercurial/subrepo.py
--- a/mercurial/subrepo.py
+++ b/mercurial/subrepo.py
@@ -1232,7 +1232,7 @@ class svnsubrepo(abstractsubrepo):
     def remove(self):
         if self.dirty():
             self.ui.warn(
-                _(b'not removing repo %s because ' b'it has changes.\n')
+                _(b'not removing repo %s because it has changes.\n')
                 % self._path
             )
             return
@@ -1572,7 +1572,7 @@ class gitsubrepo(abstractsubrepo):
         self._gitcommand([b'fetch'])
         if not self._githavelocally(revision):
             raise error.Abort(
-                _(b'revision %s does not exist in subrepository ' b'"%s"\n')
+                _(b'revision %s does not exist in subrepository "%s"\n')
                 % (revision, self._relpath)
             )
 
@@ -1630,11 +1630,11 @@ class gitsubrepo(abstractsubrepo):
         def rawcheckout():
             # no branch to checkout, check it out with no branch
             self.ui.warn(
-                _(b'checking out detached HEAD in ' b'subrepository "%s"\n')
+                _(b'checking out detached HEAD in subrepository "%s"\n')
                 % self._relpath
             )
             self.ui.warn(
-                _(b'check out a git branch if you intend ' b'to make changes\n')
+                _(b'check out a git branch if you intend to make changes\n')
             )
             checkout([b'-q', revision])
 
@@ -1822,7 +1822,7 @@ class gitsubrepo(abstractsubrepo):
             return
         if self.dirty():
             self.ui.warn(
-                _(b'not removing repo %s because ' b'it has changes.\n')
+                _(b'not removing repo %s because it has changes.\n')
                 % self._relpath
             )
             return
diff --git a/mercurial/tags.py b/mercurial/tags.py
--- a/mercurial/tags.py
+++ b/mercurial/tags.py
@@ -593,7 +593,7 @@ def _tag(
         repo.hook(b'pretag', throw=True, node=hex(node), tag=name, local=local)
         if name in branches:
             repo.ui.warn(
-                _(b"warning: tag %s conflicts with existing" b" branch name\n")
+                _(b"warning: tag %s conflicts with existing branch name\n")
                 % name
             )
 
diff --git a/mercurial/upgrade.py b/mercurial/upgrade.py
--- a/mercurial/upgrade.py
+++ b/mercurial/upgrade.py
@@ -409,7 +409,7 @@ class compressionengine(formatvariant):
     )
 
     upgrademessage = _(
-        b'revlog content will be recompressed with the new ' b'algorithm.'
+        b'revlog content will be recompressed with the new algorithm.'
     )
 
     @classmethod
@@ -1106,7 +1106,7 @@ def upgraderepo(
     missingreqs = requiredsourcerequirements(repo) - repo.requirements
     if missingreqs:
         raise error.Abort(
-            _(b'cannot upgrade repository; requirement ' b'missing: %s')
+            _(b'cannot upgrade repository; requirement missing: %s')
             % _(b', ').join(sorted(missingreqs))
         )
 
@@ -1173,7 +1173,7 @@ def upgraderepo(
         raise error.Abort(
             _(b'unknown optimization action requested: %s')
             % b', '.join(sorted(optimize)),
-            hint=_(b'run without arguments to see valid ' b'optimizations'),
+            hint=_(b'run without arguments to see valid optimizations'),
         )
 
     deficiencies = finddeficiencies(repo)
diff --git a/mercurial/util.py b/mercurial/util.py
--- a/mercurial/util.py
+++ b/mercurial/util.py
@@ -2034,12 +2034,12 @@ def checkwinfilename(path):
                 )
             if ord(c) <= 31:
                 return _(
-                    b"filename contains '%s', which is invalid " b"on Windows"
+                    b"filename contains '%s', which is invalid on Windows"
                 ) % stringutil.escapestr(c)
         base = n.split(b'.')[0]
         if base and base.lower() in _winreservednames:
             return (
-                _(b"filename contains '%s', which is reserved " b"on Windows")
+                _(b"filename contains '%s', which is reserved on Windows")
                 % base
             )
         t = n[-1:]
@@ -3506,7 +3506,7 @@ class dirs(object):
                     addpath(f)
         elif skip is not None:
             raise error.ProgrammingError(
-                b"skip character is only supported " b"with a dict source"
+                b"skip character is only supported with a dict source"
             )
         else:
             for f in map:
@@ -3583,7 +3583,7 @@ def readexactly(stream, n):
     s = stream.read(n)
     if len(s) < n:
         raise error.Abort(
-            _(b"stream ended unexpectedly" b" (got %d bytes, expected %d)")
+            _(b"stream ended unexpectedly (got %d bytes, expected %d)")
             % (len(s), n)
         )
     return s
diff --git a/mercurial/utils/cborutil.py b/mercurial/utils/cborutil.py
--- a/mercurial/utils/cborutil.py
+++ b/mercurial/utils/cborutil.py
@@ -404,7 +404,7 @@ def decodeitem(b, offset=0):
 
             if special != SPECIAL_START_ARRAY:
                 raise CBORDecodeError(
-                    b'expected array after finite set ' b'semantic tag'
+                    b'expected array after finite set semantic tag'
                 )
 
             return True, size, readcount + readcount2 + 1, SPECIAL_START_SET
@@ -746,7 +746,7 @@ class sansiodecoder(object):
                     SPECIAL_START_SET,
                 ):
                     raise CBORDecodeError(
-                        b'collections not supported as map ' b'keys'
+                        b'collections not supported as map keys'
                     )
 
                 # We do not allow special values to be used as map keys.
@@ -841,7 +841,7 @@ class sansiodecoder(object):
                     SPECIAL_START_SET,
                 ):
                     raise CBORDecodeError(
-                        b'collections not allowed as set ' b'values'
+                        b'collections not allowed as set values'
                     )
 
                 # We don't allow non-trivial types to exist as set values.
diff --git a/mercurial/vfs.py b/mercurial/vfs.py
--- a/mercurial/vfs.py
+++ b/mercurial/vfs.py
@@ -685,7 +685,7 @@ class backgroundfilecloser(object):
         """Schedule a file for closing."""
         if not self._entered:
             raise error.Abort(
-                _(b'can only call close() when context manager ' b'active')
+                _(b'can only call close() when context manager active')
             )
 
         # If a background thread encountered an exception, raise now so we fail
diff --git a/mercurial/wireprotoframing.py b/mercurial/wireprotoframing.py
--- a/mercurial/wireprotoframing.py
+++ b/mercurial/wireprotoframing.py
@@ -711,7 +711,7 @@ class identitydecoder(object):
     def __init__(self, ui, extraobjs):
         if extraobjs:
             raise error.Abort(
-                _(b'identity decoder received unexpected ' b'additional values')
+                _(b'identity decoder received unexpected additional values')
             )
 
     def decode(self, data):
@@ -745,7 +745,7 @@ class zlibdecoder(object):
 
         if extraobjs:
             raise error.Abort(
-                _(b'zlib decoder received unexpected ' b'additional values')
+                _(b'zlib decoder received unexpected additional values')
             )
 
         self._decompressor = zlib.decompressobj()
@@ -802,7 +802,7 @@ class zstd8mbdecoder(zstdbasedecoder):
     def __init__(self, ui, extraobjs):
         if extraobjs:
             raise error.Abort(
-                _(b'zstd8mb decoder received unexpected ' b'additional values')
+                _(b'zstd8mb decoder received unexpected additional values')
             )
 
         super(zstd8mbdecoder, self).__init__(maxwindowsize=8 * 1048576)
@@ -1116,7 +1116,7 @@ class serverreactor(object):
             # TODO handle decoding frames
             self._state = b'errored'
             raise error.ProgrammingError(
-                b'support for decoding stream payloads ' b'not yet implemented'
+                b'support for decoding stream payloads not yet implemented'
             )
 
         if frame.streamflags & STREAM_FLAG_END_STREAM:
@@ -1361,7 +1361,7 @@ class serverreactor(object):
         if not entry[b'requestdone']:
             self._state = b'errored'
             raise error.ProgrammingError(
-                b'should not be called without ' b'requestdone set'
+                b'should not be called without requestdone set'
             )
 
         del self._receivingcommands[requestid]
@@ -1664,9 +1664,7 @@ class serverreactor(object):
             return self._makeruncommandresult(frame.requestid)
         else:
             self._state = b'errored'
-            return self._makeerrorresult(
-                _(b'command data frame without ' b'flags')
-            )
+            return self._makeerrorresult(_(b'command data frame without flags'))
 
     def _onframeerrored(self, frame):
         return self._makeerrorresult(_(b'server already errored'))
@@ -1796,7 +1794,7 @@ class clientreactor(object):
         else:
             if not self._cansend:
                 raise error.ProgrammingError(
-                    b'sends cannot be performed on ' b'this instance'
+                    b'sends cannot be performed on this instance'
                 )
 
             if not self._hasmultiplesend:
@@ -1824,7 +1822,7 @@ class clientreactor(object):
 
         if not self._cansend:
             raise error.ProgrammingError(
-                b'sends cannot be performed on this ' b'instance'
+                b'sends cannot be performed on this instance'
             )
 
         # If the instance only allows sending once, mark that we have fired
diff --git a/mercurial/wireprotoserver.py b/mercurial/wireprotoserver.py
--- a/mercurial/wireprotoserver.py
+++ b/mercurial/wireprotoserver.py
@@ -679,7 +679,7 @@ def _runsshserver(ui, repo, fin, fout, e
                     _sshv1respondooberror(
                         fout,
                         ui.ferr,
-                        b'cannot upgrade protocols multiple ' b'times',
+                        b'cannot upgrade protocols multiple times',
                     )
                     state = b'shutdown'
                     continue
@@ -787,7 +787,7 @@ def _runsshserver(ui, repo, fin, fout, e
                     _sshv1respondooberror(
                         fout,
                         ui.ferr,
-                        b'malformed handshake protocol: ' b'missing %s' % line,
+                        b'malformed handshake protocol: missing %s' % line,
                     )
                     ok = False
                     state = b'shutdown'
diff --git a/mercurial/wireprotov1peer.py b/mercurial/wireprotov1peer.py
--- a/mercurial/wireprotov1peer.py
+++ b/mercurial/wireprotov1peer.py
@@ -143,12 +143,12 @@ class peerexecutor(object):
     def callcommand(self, command, args):
         if self._sent:
             raise error.ProgrammingError(
-                b'callcommand() cannot be used ' b'after commands are sent'
+                b'callcommand() cannot be used after commands are sent'
             )
 
         if self._closed:
             raise error.ProgrammingError(
-                b'callcommand() cannot be used ' b'after close()'
+                b'callcommand() cannot be used after close()'
             )
 
         # Commands are dispatched through methods on the peer.
diff --git a/mercurial/wireprotov1server.py b/mercurial/wireprotov1server.py
--- a/mercurial/wireprotov1server.py
+++ b/mercurial/wireprotov1server.py
@@ -41,7 +41,7 @@ urlreq = util.urlreq
 
 bundle2requiredmain = _(b'incompatible Mercurial client; bundle2 required')
 bundle2requiredhint = _(
-    b'see https://www.mercurial-scm.org/wiki/' b'IncompatibleClient'
+    b'see https://www.mercurial-scm.org/wiki/IncompatibleClient'
 )
 bundle2required = b'%s\n(%s)\n' % (bundle2requiredmain, bundle2requiredhint)
 
@@ -165,13 +165,13 @@ def wireprotocommand(name, args=None, pe
 
     if not isinstance(args, bytes):
         raise error.ProgrammingError(
-            b'arguments for version 1 commands ' b'must be declared as bytes'
+            b'arguments for version 1 commands must be declared as bytes'
         )
 
     def register(func):
         if name in commands:
             raise error.ProgrammingError(
-                b'%s command already registered ' b'for version 1' % name
+                b'%s command already registered for version 1' % name
             )
         commands[name] = wireprototypes.commandentry(
             func, args=args, transports=transports, permission=permission
diff --git a/mercurial/wireprotov2server.py b/mercurial/wireprotov2server.py
--- a/mercurial/wireprotov2server.py
+++ b/mercurial/wireprotov2server.py
@@ -140,7 +140,7 @@ def handlehttpv2request(rctx, req, res, 
         # since client does Accept it.
         res.headers[b'Content-Type'] = b'text/plain'
         res.setbodybytes(
-            _(b'client MUST send Content-Type header with ' b'value: %s\n')
+            _(b'client MUST send Content-Type header with value: %s\n')
             % FRAMINGTYPE
         )
         return
@@ -324,7 +324,7 @@ def _httpv2runcommand(
             res.status = b'403 Forbidden'
             res.headers[b'Content-Type'] = b'text/plain'
             res.setbodybytes(
-                _(b'insufficient permissions to execute ' b'command: %s')
+                _(b'insufficient permissions to execute command: %s')
                 % command[b'command']
             )
             return True
@@ -340,7 +340,7 @@ def _httpv2runcommand(
             res.status = b'200 OK'
             res.headers[b'Content-Type'] = b'text/plain'
             res.setbodybytes(
-                _(b'multiple commands cannot be issued to this ' b'URL')
+                _(b'multiple commands cannot be issued to this URL')
             )
             return True
 
@@ -725,13 +725,13 @@ def wireprotocommand(
 
     if not isinstance(args, dict):
         raise error.ProgrammingError(
-            b'arguments for version 2 commands ' b'must be declared as dicts'
+            b'arguments for version 2 commands must be declared as dicts'
         )
 
     for arg, meta in args.items():
         if arg == b'*':
             raise error.ProgrammingError(
-                b'* argument name not allowed on ' b'version 2 commands'
+                b'* argument name not allowed on version 2 commands'
             )
 
         if not isinstance(meta, dict):
@@ -773,7 +773,7 @@ def wireprotocommand(
     def register(func):
         if name in COMMANDS:
             raise error.ProgrammingError(
-                b'%s command already registered ' b'for version 2' % name
+                b'%s command already registered for version 2' % name
             )
 
         COMMANDS[name] = wireprototypes.commandentry(
@@ -890,7 +890,7 @@ def resolvenodes(repo, revisions):
 
     if not isinstance(revisions, list):
         raise error.WireprotoCommandError(
-            b'revisions must be defined as an ' b'array'
+            b'revisions must be defined as an array'
         )
 
     for spec in revisions: