1#!/bin/sh 2# 3# Copyright (c) 2005 Junio C Hamano 4# 5 6test_description='Three way merge with read-tree -m 7 8This test tries three-way merge with read-tree -m 9 10There is one ancestor (called O for Original) and two branches A 11and B derived from it. We want to do a 3-way merge between A and 12B, using O as the common ancestor. 13 14 merge A O B 15 16Decisions are made by comparing contents of O, A and B pathname 17by pathname. The result is determined by the following guiding 18principle: 19 20 - If only A does something to it and B does not touch it, take 21 whatever A does. 22 23 - If only B does something to it and A does not touch it, take 24 whatever B does. 25 26 - If both A and B does something but in the same way, take 27 whatever they do. 28 29 - If A and B does something but different things, we need a 30 3-way merge: 31 32 - We cannot do anything about the following cases: 33 34 * O does not have it. A and B both must be adding to the 35 same path independently. 36 37 * A deletes it. B must be modifying. 38 39 - Otherwise, A and B are modifying. Run 3-way merge. 40 41First, the case matrix. 42 43 - Vertical axis is for A'\''s actions. 44 - Horizontal axis is for B'\''s actions. 45 46.----------------------------------------------------------------. 47| A B | No Action | Delete | Modify | Add | 48|------------+------------+------------+------------+------------| 49| No Action | | | | | 50| | select O | delete | select B | select B | 51| | | | | | 52|------------+------------+------------+------------+------------| 53| Delete | | | ********** | can | 54| | delete | delete | merge | not | 55| | | | | happen | 56|------------+------------+------------+------------+------------| 57| Modify | | ********** | ?????????? | can | 58| | select A | merge | select A=B | not | 59| | | | merge | happen | 60|------------+------------+------------+------------+------------| 61| Add | | can | can | ?????????? | 62| | select A | not | not | select A=B | 63| | | happen | happen | merge | 64.----------------------------------------------------------------. 65 66In addition: 67 68 SS: a special case of MM, where A and B makes the same modification. 69 LL: a special case of AA, where A and B creates the same file. 70 TT: a special case of MM, where A and B makes mergeable changes. 71 DF: a special case, where A makes a directory and B makes a file. 72 73' 74. ./test-lib.sh 75. ../lib-read-tree-m-3way.sh 76 77################################################################ 78# Try merging and showing the various diffs 79 80test_expect_success \ 81'3-way merge with git-read-tree -m' \ 82"git-read-tree -m$tree_O$tree_A$tree_B" 83 84strip_object_id='s/^\([0-7]*\) [0-9a-f]* \([0-3].*\)$/\1 \2/' 85 86test_expect_success \ 87'git-ls-files --stage of the merge result' \ 88'git-ls-files --stage >current- && 89 sed -e "$strip_object_id" <current- >current' 90 91cat>expected <<\EOF 92100644 2 AA 93100644 3 AA 94100644 2 AN 95100644 1 DD 96100644 3 DF 97100644 2 DF/DF 98100644 1 DM 99100644 3 DM 100100644 1 DN 101100644 3 DN 102100644 2 LL 103100644 3 LL 104100644 1 MD 105100644 2 MD 106100644 1 MM 107100644 2 MM 108100644 3 MM 109100644 0 MN 110100644 3 NA 111100644 1 ND 112100644 2 ND 113100644 0 NM 114100644 0 NN 115100644 0 SS 116100644 1 TT 117100644 2 TT 118100644 3 TT 119100644 2 Z/AA 120100644 3 Z/AA 121100644 2 Z/AN 122100644 1 Z/DD 123100644 1 Z/DM 124100644 3 Z/DM 125100644 1 Z/DN 126100644 3 Z/DN 127100644 1 Z/MD 128100644 2 Z/MD 129100644 1 Z/MM 130100644 2 Z/MM 131100644 3 Z/MM 132100644 0 Z/MN 133100644 3 Z/NA 134100644 1 Z/ND 135100644 2 Z/ND 136100644 0 Z/NM 137100644 0 Z/NN 138EOF 139 140test_expect_success \ 141'validate merge result' \ 142'diff current expected' 143 144test_done