templates: fix ifcontains against sets with length > 1 (issue4259)

Previously the ifcontains revset was checking against the set using a pure
__contains__ check.  It turns out the set was actually a list of
formatted strings meant for ui output, which meant the contains check failed if
the formatted string wasn't significantly different from the raw value.

This change makes it check against the raw data, prior to it being formatted.

mercurial/templater.py

@@ -310,7 +310,9 b' def ifcontains(context, mapping, args):'
     item = stringify(args[0][0](context, mapping, args[0][1]))
     items = args[1][0](context, mapping, args[1][1])
 
-    if item in items:
+    # Iterating over items gives a formatted string, so we iterate
+    # directly over the raw values.
+    if item in [i.values()[0] for i in items()]:
         yield _evalifliteral(args[2], context, mapping)
     elif len(args) == 4:
         yield _evalifliteral(args[3], context, mapping)

tests/test-command-template.t

@@ -1819,6 +1819,11 b' Test revset function'
   1 not current rev
   0 not current rev
 
+  $ hg log --template '{rev} {ifcontains(rev, revset(". + .^"), "match rev", "not match rev")}\n'
+  2 match rev
+  1 match rev
+  0 not match rev
+
   $ hg log --template '{rev} Parents: {revset("parents(%s)", rev)}\n'
   2 Parents: 1
   1 Parents: 0