subrepo: drop the default value of None for the archive matcher

This was flagged by pytype after adding hints to `match.subdirmatcher` that it
takes a non-optional matcher.  That matcher argument is used without a guard in
the subdirmatcher constructor, so that's the correct restriction.

I don't think this fixes a bug in practice because the only way these are
invoked is either by a parent `hgsubrepo.archive()`, `archival.archive()`, or
the largefiles override of these.  The `hgsubrepo.archive()` case (and the
largefiles override) uses what the caller provided, so the caller will
eventually be `archival.archive()` (or the largfiles override) up the call
chain.  The `archival.archive()` method also has None for its matcher's default
arg.  However, the three callers of that (`commands.archive()`,
`webcommands.archive()`, and `extdiff.snapshot()`) all provide a matcher
argument, so the None case can never occur unless a 3rd party extension swaps it
for None.  Sadly, we can't make the argument on the `archival.archive()`
non-optional because there is a kwarg prior to it.

Even though the largefiles override of `archival.archive()` is provided a valid
matcher, we duplicate the internal creation of the matcher that the original
`archival.archive()` does for consistency.  By eliminating an impossible to hit
case, we can simplify some of the subrepo code too, by dropping unreachable
code.

hgext/largefiles/overrides.py

@@ -1252,8 +1252,11 b' def overridearchive('
     else:
         prefix = archival.tidyprefix(dest, kind, prefix)
 
+    if not match:
+        match = scmutil.matchall(repo)
+
     def write(name, mode, islink, getdata):
-        if match and not match(name):
+        if not match(name):
             return
         data = getdata()
         if decode:
@@ -1314,7 +1317,7 b' def overridearchive('
 
 
 @eh.wrapfunction(subrepo.hgsubrepo, 'archive')
-def hgsubrepoarchive(orig, repo, archiver, prefix, match=None, decode=True):
+def hgsubrepoarchive(orig, repo, archiver, prefix, match, decode=True):
     lfenabled = hasattr(repo._repo, '_largefilesenabled')
     if not lfenabled or not repo._repo.lfstatus:
         return orig(repo, archiver, prefix, match, decode)
@@ -1329,7 +1332,7 b' def hgsubrepoarchive(orig, repo, archive'
     def write(name, mode, islink, getdata):
         # At this point, the standin has been replaced with the largefile name,
         # so the normal matcher works here without the lfutil variants.
-        if match and not match(f):
+        if not match(f):
             return
         data = getdata()
         if decode:

mercurial/subrepo.py

@@ -363,11 +363,8 b' class abstractsubrepo:'
         """handle the files command for this subrepo"""
         return 1
 
-    def archive(self, archiver, prefix, match=None, decode=True):
-        if match is not None:
-            files = [f for f in self.files() if match(f)]
-        else:
-            files = self.files()
+    def archive(self, archiver, prefix, match, decode=True):
+        files = [f for f in self.files() if match(f)]
         total = len(files)
         relpath = subrelpath(self)
         progress = self.ui.makeprogress(
@@ -652,11 +649,9 b' class hgsubrepo(abstractsubrepo):'
             )
 
     @annotatesubrepoerror
-    def archive(self, archiver, prefix, match=None, decode=True):
+    def archive(self, archiver, prefix, match, decode=True):
         self._get(self._state + (b'hg',))
-        files = self.files()
-        if match:
-            files = [f for f in files if match(f)]
+        files = [f for f in self.files() if match(f)]
         rev = self._state[1]
         ctx = self._repo[rev]
         scmutil.prefetchfiles(
@@ -1911,7 +1906,7 b' class gitsubrepo(abstractsubrepo):'
             else:
                 self.wvfs.unlink(f)
 
-    def archive(self, archiver, prefix, match=None, decode=True):
+    def archive(self, archiver, prefix, match, decode=True):
         total = 0
         source, revision = self._state
         if not revision:
@@ -1932,7 +1927,7 b' class gitsubrepo(abstractsubrepo):'
             if info.isdir():
                 continue
             bname = pycompat.fsencode(info.name)
-            if match and not match(bname):
+            if not match(bname):
                 continue
             if info.issym():
                 data = info.linkname