# HG changeset patch
# User Alexander Plavin <alexander@plav.in>
# Date 1375824091 -14400
# Node ID f0b992a9be9c3a5574de8abb9219a2897619516f
# Parent  2f9d5c5256ea4db1b7c52a892b9e2e977ceb7af4
revset: add helper function to get functions used in a revset parse tree

Will be used to determine whether all functions used in a hgweb search query
are allowed there.

diff -r 2f9d5c5256ea -r f0b992a9be9c mercurial/revset.py
--- a/mercurial/revset.py	Fri Aug 09 22:52:58 2013 +0400
+++ b/mercurial/revset.py	Wed Aug 07 01:21:31 2013 +0400
@@ -1941,5 +1941,16 @@
     else:
         return 0
 
+def funcsused(tree):
+    if not isinstance(tree, tuple) or tree[0] in ('string', 'symbol'):
+        return set()
+    else:
+        funcs = set()
+        for s in tree[1:]:
+            funcs |= funcsused(s)
+        if tree[0] == 'func':
+            funcs.add(tree[1][1])
+        return funcs
+
 # tell hggettext to extract docstrings from these functions:
 i18nfunctions = symbols.values()