compare grep result between target and its parent
I found that typical case is that grep target is added at (*) revision
in the tree shown below.
+--- 1(*) --- 3
0
+--- 2 ------ 4
Now, I expect 'hg grep --all' to show only rev:1 which is first
appearance of target line.
But 'hg grep --all' will tell:
target line dis-appeared at 3 => 4
target line appeared at 2 => 3
target line dis-appeared at 1 => 2
target line appeared at 0 => 1
because current 'hg grep' implementation compares not between target
revision and its parent, but between neighbor revisions in walkthrough
order.
I checked performance of this patch by "hg grep --follow --all
walkchangerevs" on whole Mercurial repo, and patched version could
complete as fast as un-patched one.
35fb62a3a673d5322f6274a44ba6456e5e4b3b37 0 iD8DBQBEYmO2ywK+sNU5EO8RAnaYAKCO7x15xUn5mnhqWNXqk/ehlhRt2QCfRDfY0LrUq2q4oK/KypuJYPHgq1A=
2be3001847cb18a23c403439d9e7d0ace30804e9 0 iD8DBQBExUbjywK+sNU5EO8RAhzxAKCtyHAQUzcTSZTqlfJ0by6vhREwWQCghaQFHfkfN0l9/40EowNhuMOKnJk=
36a957364b1b89c150f2d0e60a99befe0ee08bd3 0 iD8DBQBFfL2QywK+sNU5EO8RAjYFAKCoGlaWRTeMsjdmxAjUYx6diZxOBwCfY6IpBYsKvPTwB3oktnPt5Rmrlys=
27230c29bfec36d5540fbe1c976810aefecfd1d2 0 iD8DBQBFheweywK+sNU5EO8RAt7VAKCrqJQWT2/uo2RWf0ZI4bLp6v82jACgjrMdsaTbxRsypcmEsdPhlG6/8F4=
fb4b6d5fe100b0886f8bc3d6731ec0e5ed5c4694 0 iD8DBQBGgHicywK+sNU5EO8RAgNxAJ0VG8ixAaeudx4sZbhngI1syu49HQCeNUJQfWBgA8bkJ2pvsFpNxwYaX3I=
23889160905a1b09fffe1c07378e9fc1827606eb 0 iD8DBQBHGTzoywK+sNU5EO8RAr/UAJ0Y8s4jQtzgS+G9vM8z6CWBThZ8fwCcCT5XDj2XwxKkz/0s6UELwjsO3LU=
bae2e9c838e90a393bae3973a7850280413e091a 0 iD8DBQBH6DO5ywK+sNU5EO8RAsfrAJ0e4r9c9GF/MJsM7Xjd3NesLRC3+ACffj6+6HXdZf8cswAoFPO+DY00oD0=
d5cbbe2c49cee22a9fbeb9ea41daa0ac4e26b846 0 iD8DBQBINdwsywK+sNU5EO8RAjIUAKCPmlFJSpsPAAUKF+iNHAwVnwmzeQCdEXrL27CWclXuUKdbQC8De7LICtE=
d2375bbee6d47e62ba8e415c86e83a465dc4dce9 0 iD8DBQBIo1wpywK+sNU5EO8RAmRNAJ94x3OFt6blbqu/yBoypm/AJ44fuACfUaldXcV5z9tht97hSp22DVTEPGc=
2a67430f92f15ea5159c26b09ec4839a0c549a26 0 iEYEABECAAYFAkk1hykACgkQywK+sNU5EO85QACeNJNUanjc2tl4wUoPHNuv+lSj0ZMAoIm93wSTc/feyYnO2YCaQ1iyd9Nu
3773e510d433969e277b1863c317b674cbee2065 0 iEYEABECAAYFAklNbbAACgkQywK+sNU5EO8o+gCfeb2/lfIJZMvyDA1m+G1CsBAxfFsAoIa6iAMG8SBY7hW1Q85Yf/LXEvaE
11a4eb81fb4f4742451591489e2797dc47903277 0 iEYEABECAAYFAklcAnsACgkQywK+sNU5EO+uXwCbBVHNNsLy1g7BlAyQJwadYVyHOXoAoKvtAVO71+bv7EbVoukwTzT+P4Sx
11efa41037e280d08cfb07c09ad485df30fb0ea8 0 iEYEABECAAYFAkmvJRQACgkQywK+sNU5EO9XZwCeLMgDgPSMWMm6vgjL4lDs2pEc5+0AnRxfiFbpbBfuEFTqKz9nbzeyoBlx
02981000012e3adf40c4849bd7b3d5618f9ce82d 0 iEYEABECAAYFAknEH3wACgkQywK+sNU5EO+uXwCeI+LbLMmhjU1lKSfU3UWJHjjUC7oAoIZLvYDGOL/tNZFUuatc3RnZ2eje