test-bheads: use a case-insensitive set of filenames (issue2274) This prevents false negatives on case-insensitive systems.

mail: ensure that Python2.4 to 2.7 use the same header format Wrapping format for long headers changed in Python2.7 (see Python issue1974). Adopt the Python2.7 behaviour and backport it for 2.4-2.6

filelog: cmp: don't read data if hashes are identical (issue2273) filelog.renamed() is an expensive call as it reads the filelog if p1 == nullid. It's more efficient to first compute the hash, and to bail early if the computed hash is the same as the stored nodeid. 'samehashes' variable is not strictly necessary, but helps for comprehension.