log: fix -fr'wdir()' PATH to follow newly added file

Testing filelog doesn't make sense in this case because the file existence
is tested against the specified changectxs. If the filelog is empty and
if startctxs != [wctx], 'f not in c' should be triggered.

mercurial/logcmdutil.py

@@ -698,12 +698,7 b' def _makematcher(repo, revs, pats, opts)'
                 # take the slow path.
                 if any(f not in c for c in startctxs):
                     slowpath = True
-                    continue
-                filelog = repo.file(f)
-                if not filelog:
-                    raise error.Abort(
-                        _(b'cannot follow nonexistent file: "%s"') % f
-                    )
+                    break
         elif follow:
             for f in match.files():
                 if f not in wctx:
@@ -722,6 +717,8 b' def _makematcher(repo, revs, pats, opts)'
                         )
                 filelog = repo.file(f)
                 if not filelog:
+                    # A file exists in wdir but not in history, which means
+                    # the file isn't committed yet.
                     raise error.Abort(
                         _(b'cannot follow nonexistent file: "%s"') % f
                     )

tests/test-log.t

@@ -2295,15 +2295,21 b' follow files from wdir'
    1 files changed, 1 insertions(+), 0 deletions(-)
   
 
- BROKEN: added file should exist in wdir
   $ hg log -T '== {rev} ==\n' -fr'wdir()' --git --stat d1/f2
-  abort: cannot follow nonexistent file: "d1/f2"
-  [255]
+  == 2147483647 ==
+   d1/f2 |  1 +
+   1 files changed, 1 insertions(+), 0 deletions(-)
+  
 
- BROKEN: copied file should exist in wdir
   $ hg log -T '== {rev} ==\n' -fr'wdir()' --git --stat f1-copy
-  abort: cannot follow nonexistent file: "f1-copy"
-  [255]
+  == 2147483647 ==
+   f1-copy |  1 +
+   1 files changed, 1 insertions(+), 0 deletions(-)
+  
+  == 0 ==
+   d1/f1 |  1 +
+   1 files changed, 1 insertions(+), 0 deletions(-)
+  
 
   $ hg log -T '== {rev} ==\n' -fr'wdir()' --git --stat notfound
   notfound: $ENOENT$