--- /dev/null
+#!/bin/sh
+#
+# Copyright (c) 2005 Junio C Hamano
+#
+
+test_description='Three way merge with read-tree -m
+
+This test tries three-way merge with read-tree -m
+
+There is one ancestor (called O for Original) and two branches A
+and B derived from it. We want to do a 3-way merge between A and
+B, using O as the common ancestor.
+
+ merge A O B
+
+Decisions are made by comparing contents of O, A and B pathname
+by pathname. The result is determined by the following guiding
+principle:
+
+ - If only A does something to it and B does not touch it, take
+ whatever A does.
+
+ - If only B does something to it and A does not touch it, take
+ whatever B does.
+
+ - If both A and B does something but in the same way, take
+ whatever they do.
+
+ - If A and B does something but different things, we need a
+ 3-way merge:
+
+ - We cannot do anything about the following cases:
+
+ * O does not have it. A and B both must be adding to the
+ same path independently.
+
+ * A deletes it. B must be modifying.
+
+ - Otherwise, A and B are modifying. Run 3-way merge.
+
+First, the case matrix.
+
+ - Vertical axis is for A'\''s actions.
+ - Horizontal axis is for B'\''s actions.
+
+.----------------------------------------------------------------.
+| A B | No Action | Delete | Modify | Add |
+|------------+------------+------------+------------+------------|
+| No Action | | | | |
+| | select O | delete | select B | select B |
+| | | | | |
+|------------+------------+------------+------------+------------|
+| Delete | | | ********** | can |
+| | delete | delete | merge | not |
+| | | | | happen |
+|------------+------------+------------+------------+------------|
+| Modify | | ********** | ?????????? | can |
+| | select A | merge | select A=B | not |
+| | | | merge | happen |
+|------------+------------+------------+------------+------------|
+| Add | | can | can | ?????????? |
+| | select A | not | not | select A=B |
+| | | happen | happen | merge |
+.----------------------------------------------------------------.
+
+In addition:
+
+ SS: a special case of MM, where A and B makes the same modification.
+ LL: a special case of AA, where A and B creates the same file.
+ TT: a special case of MM, where A and B makes mergeable changes.
+ DF: a special case, where A makes a directory and B makes a file.
+
+'
+
+. ./test-lib.sh
+
+# Original tree.
+mkdir Z
+for a in N D M
+do
+ for b in N D M
+ do
+ p=$a$b
+ echo This is $p from the original tree. >$p
+ echo This is Z/$p from the original tree. >Z/$p
+ test_expect_success \
+ "adding test file $p and Z/$p" \
+ 'git-update-cache --add $p &&
+ git-update-cache --add Z/$p'
+ done
+done
+echo This is SS from the original tree. >SS
+test_expect_success \
+ 'adding test file SS' \
+ 'git-update-cache --add SS'
+cat >TT <<\EOF
+This is a trivial merge sample text.
+Branch A is expected to upcase this word, here.
+There are some filler lines to avoid diff context
+conflicts here,
+like this one,
+and this one,
+and this one is yet another one of them.
+At the very end, here comes another line, that is
+the word, expected to be upcased by Branch B.
+This concludes the trivial merge sample file.
+EOF
+test_expect_success \
+ 'adding test file TT' \
+ 'git-update-cache --add TT'
+test_expect_success \
+ 'prepare initial tree' \
+ 'tree_O=$(git-write-tree)'
+
+test_expect_success \
+ 'commit initial tree' \
+ 'commit_O=$(echo "Original tree for the merge test." |
+ git-commit-tree $tree_O)'
+echo $commit_O >.git/HEAD-O
+
+################################################################
+# Branch A and B makes the changes according to the above matrix.
+
+################################################################
+# Branch A
+
+to_remove=$(echo D? Z/D?)
+rm -f $to_remove
+test_expect_success \
+ 'change in branch A (removal)' \
+ 'git-update-cache --remove $to_remove'
+
+for p in M? Z/M?
+do
+ echo This is modified $p in the branch A. >$p
+ test_expect_success \
+ 'change in branch A (modification)' \
+ "git-update-cache $p"
+done
+
+for p in AN AA Z/AN Z/AA
+do
+ echo This is added $p in the branch A. >$p
+ test_expect_success \
+ 'change in branch A (addition)' \
+ "git-update-cache --add $p"
+done
+
+echo This is SS from the modified tree. >SS
+echo This is LL from the modified tree. >LL
+test_expect_success \
+ 'change in branch A (addition)' \
+ 'git-update-cache --add LL &&
+ git-update-cache SS'
+mv TT TT-
+sed -e '/Branch A/s/word/WORD/g' <TT- >TT
+rm -f TT-
+test_expect_success \
+ 'change in branch A (edit)' \
+ 'git-update-cache TT'
+
+mkdir DF
+echo Branch A makes a file at DF/DF, creating a directory DF. >DF/DF
+test_expect_success \
+ 'change in branch A (change file to directory)' \
+ 'git-update-cache --add DF/DF'
+
+test_expect_success \
+ 'recording branch A tree' \
+ 'tree_A=$(git-write-tree)'
+test_expect_success \
+ 'committing branch A changes' \
+ 'commit_A=$(echo "Branch A for the merge test." |
+ git-commit-tree $tree_A -p $commit_O)'
+echo $commit_A >.git/HEAD-A
+
+################################################################
+# Branch B
+# Start from O
+
+rm -rf [NDMASLT][NDMASLT] Z DF
+mkdir Z
+test_expect_success \
+ 'reading original tree and checking out' \
+ 'git-read-tree $tree_O &&
+ git-checkout-cache -a'
+
+to_remove=$(echo ?D Z/?D)
+rm -f $to_remove
+test_expect_success \
+ 'change in branch B (removal)' \
+ "git-update-cache --remove $to_remove"
+
+for p in ?M Z/?M
+do
+ echo This is modified $p in the branch B. >$p
+ test_expect_success \
+ 'change in branch B (modification)' \
+ "git-update-cache $p"
+done
+
+for p in NA AA Z/NA Z/AA
+do
+ echo This is added $p in the branch B. >$p
+ test_expect_success \
+ 'change in branch B (addition)' \
+ "git-update-cache --add $p"
+done
+echo This is SS from the modified tree. >SS
+echo This is LL from the modified tree. >LL
+test_expect_success \
+ 'change in branch B (addition and modification)' \
+ 'git-update-cache --add LL &&
+ git-update-cache SS'
+mv TT TT-
+sed -e '/Branch B/s/word/WORD/g' <TT- >TT
+rm -f TT-
+test_expect_success \
+ 'change in branch B (modification)' \
+ 'git-update-cache TT'
+
+echo Branch B makes a file at DF. >DF
+test_expect_success \
+ 'change in branch B (addition of a file to conflict with directory)' \
+ 'git-update-cache --add DF'
+
+test_expect_success \
+ 'recording branch B tree' \
+ 'tree_B=$(git-write-tree)'
+test_expect_success \
+ 'committing branch B changes' \
+ 'commit_B=$(echo "Branch B for the merge test." |
+ git-commit-tree $tree_B -p $commit_O)'
+echo $commit_B >.git/HEAD-B
+
+################################################################
+# Done preparation.
+
+test_debug '
+ for T in O A B
+ do
+ echo "# $T $(eval git-cat-file commit \$commit_$T | sed -e 1q)"
+ done
+'
+
+################################################################
+# Try merging and showing the various diffs
+
+test_expect_success \
+ '3-way merge with git-read-tree -m' \
+ "git-read-tree -m $tree_O $tree_A $tree_B"
+
+strip_object_id='s/^\([0-7]*\) [0-9a-f]* \([0-3].*\)$/\1 \2/'
+
+test_expect_success \
+ 'git-ls-files --stage of the merge result' \
+ 'git-ls-files --stage >current- &&
+ sed -e "$strip_object_id" <current- >current'
+
+cat >expected <<\EOF
+100644 2 AA
+100644 3 AA
+100644 2 AN
+100644 1 DD
+100644 3 DF
+100644 2 DF/DF
+100644 1 DM
+100644 3 DM
+100644 1 DN
+100644 3 DN
+100644 2 LL
+100644 3 LL
+100644 1 MD
+100644 2 MD
+100644 1 MM
+100644 2 MM
+100644 3 MM
+100644 0 MN
+100644 3 NA
+100644 1 ND
+100644 2 ND
+100644 0 NM
+100644 0 NN
+100644 0 SS
+100644 1 TT
+100644 2 TT
+100644 3 TT
+100644 2 Z/AA
+100644 3 Z/AA
+100644 2 Z/AN
+100644 1 Z/DD
+100644 1 Z/DM
+100644 3 Z/DM
+100644 1 Z/DN
+100644 3 Z/DN
+100644 1 Z/MD
+100644 2 Z/MD
+100644 1 Z/MM
+100644 2 Z/MM
+100644 3 Z/MM
+100644 0 Z/MN
+100644 3 Z/NA
+100644 1 Z/ND
+100644 2 Z/ND
+100644 0 Z/NM
+100644 0 Z/NN
+EOF
+
+test_expect_success \
+ 'validate merge result' \
+ 'diff current expected'
+
+test_done
projects / git.git / commitdiff