Merge branch 'master' (early part) into pd/bash-4-completion

* 'master' (early part): (529 commits)
  completion: fix zsh check under bash with 'set -u'
  Fix copy-pasted comments related to tree diff handling.
  Git 1.7.3.2
  {cvs,svn}import: use the new 'git read-tree --empty'
  t/t9001-send-email.sh: fix stderr redirection in 'Invalid In-Reply-To'
  Clarify and extend the "git diff" format documentation
  git-show-ref.txt: clarify the pattern matching
  documentation: git-config minor cleanups
  Update test script annotate-tests.sh to handle missing/extra authors
  Better advice on using topic branches for kernel development
  Documentation: update implicit "--no-index" behavior in "git diff"
  Documentation: expand 'git diff' SEE ALSO section
  Documentation: diff can compare blobs
  Documentation: gitrevisions is in section 7
  fast-import: Allow filemodify to set the root
  shell portability: no "export VAR=VAL"
  CodingGuidelines: reword parameter expansion section
  Documentation: update-index: -z applies also to --index-info
  gitweb: Improve behavior for actionless path_info gitweb URLs
  gitweb: Fix bug in evaluate_path_info
  ...

Conflicts:
	GIT-VERSION-GEN
	RelNotes
	contrib/completion/git-completion.bash

1 files changed, 119 insertions, 8 deletions

diff --git a/t/t7405-submodule-merge.sh b/t/t7405-submodule-merge.sh
index 4a7b8933f4..7e2e258950 100755
--- a/t/t7405-submodule-merge.sh
+++ b/t/t7405-submodule-merge.sh
@@ -54,21 +54,132 @@ test_expect_success setup '
 	git merge -s ours a
 '
 
-test_expect_success 'merging with modify/modify conflict' '
+# History setup
+#
+#      b
+#    /   \
+#   a     d
+#    \   /
+#      c
+#
+# a in the main repository records to sub-a in the submodule and
+# analogous b and c. d should be automatically found by merging c into
+# b in the main repository.
+test_expect_success 'setup for merge search' '
+	mkdir merge-search &&
+	(cd merge-search &&
+	git init &&
+	mkdir sub &&
+	(cd sub &&
+	 git init &&
+	 echo "file-a" > file-a &&
+	 git add file-a &&
+	 git commit -m "sub-a" &&
+	 git branch sub-a) &&
+	git add sub &&
+	git commit -m "a" &&
+	git branch a &&
+
+	git checkout -b b &&
+	(cd sub &&
+	 git checkout -b sub-b &&
+	 echo "file-b" > file-b &&
+	 git add file-b &&
+	 git commit -m "sub-b") &&
+	git commit -a -m "b" &&
+
+	git checkout -b c a &&
+	(cd sub &&
+	 git checkout -b sub-c sub-a &&
+	 echo "file-c" > file-c &&
+	 git add file-c &&
+	 git commit -m "sub-c") &&
+	git commit -a -m "c" &&
 
-	git checkout -b test1 a &&
-	test_must_fail git merge b &&
-	test -f .git/MERGE_MSG &&
-	git diff &&
-	test -n "$(git ls-files -u)"
+	git checkout -b d a &&
+	(cd sub &&
+	 git checkout -b sub-d sub-b &&
+	 git merge sub-c) &&
+	git commit -a -m "d" &&
+	git branch test b)
 '
 
-test_expect_success 'merging with a modify/modify conflict between merge bases' '
+test_expect_success 'merge with one side as a fast-forward of the other' '
+	(cd merge-search &&
+	 git checkout -b test-forward b &&
+	 git merge d &&
+	 git ls-tree test-forward sub | cut -f1 | cut -f3 -d" " > actual &&
+	 (cd sub &&
+	  git rev-parse sub-d > ../expect) &&
+	 test_cmp actual expect)
+'
 
+test_expect_success 'merging should conflict for non fast-forward' '
+	(cd merge-search &&
+	 git checkout -b test-nonforward b &&
+	 (cd sub &&
+	  git rev-parse sub-d > ../expect) &&
+	 test_must_fail git merge c 2> actual  &&
+	 grep $(cat expect) actual > /dev/null &&
+	 git reset --hard)
+'
+
+test_expect_success 'merging should fail for ambiguous common parent' '
+	(cd merge-search &&
+	git checkout -b test-ambiguous b &&
+	(cd sub &&
+	 git checkout -b ambiguous sub-b &&
+	 git merge sub-c &&
+	 git rev-parse sub-d > ../expect1 &&
+	 git rev-parse ambiguous > ../expect2) &&
+	test_must_fail git merge c 2> actual &&
+	grep $(cat expect1) actual > /dev/null &&
+	grep $(cat expect2) actual > /dev/null &&
+	git reset --hard)
+'
+
+# in a situation like this
+#
+# submodule tree:
+#
+#    sub-a --- sub-b --- sub-d
+#
+# main tree:
+#
+#    e (sub-a)
+#   /
+#  bb (sub-b)
+#   \
+#    f (sub-d)
+#
+# A merge between e and f should fail because one of the submodule
+# commits (sub-a) does not descend from the submodule merge-base (sub-b).
+#
+test_expect_success 'merging should fail for changes that are backwards' '
+	(cd merge-search &&
+	git checkout -b bb a &&
+	(cd sub &&
+	 git checkout sub-b) &&
+	git commit -a -m "bb" &&
+
+	git checkout -b e bb &&
+	(cd sub &&
+	 git checkout sub-a) &&
+	git commit -a -m "e" &&
+
+	git checkout -b f bb &&
+	(cd sub &&
+	 git checkout sub-d) &&
+	git commit -a -m "f" &&
+
+	git checkout -b test-backward e &&
+	test_must_fail git merge f)
+'
+
+test_expect_success 'merging with a modify/modify conflict between merge bases' '
 	git reset --hard HEAD &&
 	git checkout -b test2 c &&
 	git merge d
-
 '
 
 test_done