revrange: build balanced tree of addsets from revisions (issue4565) This reduces the stack depth from O(n) to O(log(n)). Therefore, repeated -rREV options will never exceed the Python stack limit. Currently it depends on private revset._combinesets() function. But at some point, we'll be able to drop the old-style parser, and revrange() can be completely rewritten without using _combinesets(): trees = [parse(s) for s in revs] optimize(('or',) + trees) # combine trees and optimize at once ... Blockers that prevent eliminating old-style parser: - nullary ":" operator - revrange(repo, [intrev, ...]), can be mapped to 'rev(%d)' ? - revrange(repo, [binnode, ...]), should be banned ?

--- a/tests/test-revset.t	Sun May 24 17:59:55 2015 +0900
+++ b/tests/test-revset.t	Sun May 24 18:11:33 2015 +0900
@@ -1084,6 +1084,13 @@
   0
   1
 
+test that repeated `-r` options never eat up stack (issue4565)
+(uses `-r 0::1` to avoid possible optimization at old-style parser)
+
+  $ hg log -T '{rev}\n' `python -c "for i in xrange(500): print '-r 0::1 ',"`
+  0
+  1
+
 check that conversion to only works
   $ try --optimize '::3 - ::1'
   (minus