censor: make various path forms available like other Mercurial commands

Before this patch, censored file should be exactly "a path relative to
repository root" regardless of current working directory, because "hg
censor" passes "path" to "repo.file()" directly without any
preparations.

To make various path forms available like other Mercurial commands,
this patch gets a target file path in the way of "hg parents FILE".

Getting "wctx" is relocated to reuse "wctx" for efficiency.

hgext/censor.py

@@ -47,6 +47,12 b" def censor(ui, repo, path, rev='', tombs"
     if not rev:
         raise util.Abort(_('must specify revision to censor'))
 
+    wctx = repo[None]
+
+    m = scmutil.match(wctx, (path,))
+    if m.anypats() or len(m.files()) != 1:
+        raise util.Abort(_('can only specify an explicit filename'))
+    path = m.files()[0]
     flog = repo.file(path)
     if not len(flog):
         raise util.Abort(_('cannot censor file with no history'))
@@ -70,7 +76,6 b" def censor(ui, repo, path, rev='', tombs"
         raise util.Abort(_('cannot censor file in heads (%s)') % headlist,
             hint=_('clean/delete and commit first'))
 
-    wctx = repo[None]
     wp = wctx.parents()
     if ctx.node() in [p.node() for p in wp]:
         raise util.Abort(_('cannot censor working directory'),

tests/test-censor.t

@@ -72,7 +72,10 b' Try to censor revision with too large of'
 
 Censor revision with 2 offenses
 
-  $ hg censor -r $C2 -t "remove password" target
+(this also tests file pattern matching: path relative to cwd case)
+
+  $ mkdir -p foo/bar/baz
+  $ hg --cwd foo/bar/baz censor -r $C2 -t "remove password" ../../../target
   $ hg cat -r $H1 target
   Tainted file is now sanitized
   $ hg cat -r $H2 target
@@ -89,7 +92,9 b' Censor revision with 2 offenses'
 
 Censor revision with 1 offense
 
-  $ hg censor -r $C1 target
+(this also tests file pattern matching: with 'path:' scheme)
+
+  $ hg --cwd foo/bar/baz censor -r $C1 path:target
   $ hg cat -r $H1 target
   Tainted file is now sanitized
   $ hg cat -r $H2 target