match: remove special-casing of always-matching patterns in patternmatcher

match: remove special-casing of always-matching patterns in patternmatcher

This moves the optimization for patterns that match everything to the
caller, so we can remove it from patternmatcher.

Note that we need to teach alwaysmatcher to use relative paths now in
cases like "hg files .." from inside mercurial/, because while it
still matches everything, paths should be printed relative to the
working directory.

--- a/mercurial/match.py	Fri May 19 12:47:45 2017 -0700
+++ b/mercurial/match.py	Fri May 19 13:16:15 2017 -0700
@@ -146,8 +146,11 @@
         m = exactmatcher(root, cwd, patterns, badfn)
     elif patterns:
         kindpats = normalize(patterns, default, root, cwd, auditor, warn)
-        m = patternmatcher(root, cwd, kindpats, ctx=ctx,
-                           listsubrepos=listsubrepos, badfn=badfn)
+        if _kindpatsalwaysmatch(kindpats):
+            m = alwaysmatcher(root, cwd, badfn, relativeuipath=True)
+        else:
+            m = patternmatcher(root, cwd, kindpats, ctx=ctx,
+                               listsubrepos=listsubrepos, badfn=badfn)
     else:
         # It's a little strange that no patterns means to match everything.
         # Consider changing this to match nothing (probably adding a
@@ -320,9 +323,9 @@
 class alwaysmatcher(basematcher):
     '''Matches everything.'''
 
-    def __init__(self, root, cwd, badfn=None):
+    def __init__(self, root, cwd, badfn=None, relativeuipath=False):
         super(alwaysmatcher, self).__init__(root, cwd, badfn,
-                                            relativeuipath=False)
+                                            relativeuipath=relativeuipath)
 
     def always(self):
         return True
@@ -342,26 +345,17 @@
                  badfn=None):
         super(patternmatcher, self).__init__(root, cwd, badfn)
 
-        if not _kindpatsalwaysmatch(kindpats):
-            self._files = _explicitfiles(kindpats)
-            self._anypats = _anypats(kindpats)
-            self.patternspat, pm = _buildmatch(ctx, kindpats, '$',
-                                               listsubrepos, root)
-            self._always = False
-            self.matchfn = pm
-        else:
-            self._anypats = False
-            self.patternspat = None
-            self._always = True
-            self.matchfn = lambda f: True
+        self._files = _explicitfiles(kindpats)
+        self._anypats = _anypats(kindpats)
+        self.patternspat, pm = _buildmatch(ctx, kindpats, '$', listsubrepos,
+                                           root)
+        self.matchfn = pm
 
     @propertycache
     def _dirs(self):
         return set(util.dirs(self._fileset)) | {'.'}
 
     def visitdir(self, dir):
-        if self.always():
-            return 'all'
         if self.prefix() and dir in self._fileset:
             return 'all'
         return ('.' in self._fileset or
@@ -373,9 +367,6 @@
     def anypats(self):
         return self._anypats
 
-    def always(self):
-        return self._always
-
     def __repr__(self):
         return ('<patternmatcher patterns=%r>' % self.patternspat)