match: drop support for empty pattern list in patternmatcher

Since the caller now deals with empty pattern lists, we can drop that
support in the patternmatcher. It now gets the more logical behavior
of matching nothing when no patterns are given (although there is no
in-core caller that will pass no patterns).

mercurial/match.py

@@ -341,36 +341,21 b' class patternmatcher(basematcher):'
     def __init__(self, root, cwd, normalize, patterns, default='glob',
                  auditor=None, ctx=None, listsubrepos=False, warn=None,
                  badfn=None):
-        super(patternmatcher, self).__init__(root, cwd, badfn,
-                                             relativeuipath=bool(patterns))
-
-        self._anypats = False
-        self._always = False
-        self.patternspat = None
+        super(patternmatcher, self).__init__(root, cwd, badfn)
 
-        matchfns = []
-        if patterns:
-            kindpats = normalize(patterns, default, root, cwd, auditor, warn)
-            if not _kindpatsalwaysmatch(kindpats):
-                self._files = _explicitfiles(kindpats)
-                self._anypats = self._anypats or _anypats(kindpats)
-                self.patternspat, pm = _buildmatch(ctx, kindpats, '$',
-                                                   listsubrepos, root)
-                matchfns.append(pm)
-
-        if not matchfns:
-            m = util.always
+        kindpats = normalize(patterns, default, root, cwd, auditor, warn)
+        if not _kindpatsalwaysmatch(kindpats):
+            self._files = _explicitfiles(kindpats)
+            self._anypats = _anypats(kindpats)
+            self.patternspat, pm = _buildmatch(ctx, kindpats, '$',
+                                               listsubrepos, root)
+            self._always = False
+            self.matchfn = pm
+        else:
+            self._anypats = False
+            self.patternspat = None
             self._always = True
-        elif len(matchfns) == 1:
-            m = matchfns[0]
-        else:
-            def m(f):
-                for matchfn in matchfns:
-                    if not matchfn(f):
-                        return False
-                return True
-
-        self.matchfn = m
+            self.matchfn = lambda f: True
 
     @propertycache
     def _dirs(self):