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[PATCH 1/3] git-merge: Honor pre-merge hook

From
Michael J Gruber <git@drmicha.warpmail.net>
Date
Sep 5, 2012, 13:39 UTC
Message-ID
<dc8ebcd7f7b80ff930c04b5a407361ba8f2f077f.1346851863.git.git@drmicha.warpmail.net>
In-Reply-To
<cover.1346851863.git.git@drmicha.warpmail.net>

git-merge does not honor the pre-commit hook when doing automatic merge commits, and for compatibility reasons this is going to stay.

Introduce a pre-merge hook which is called for an automatic merge commit just like pre-commit is called for a non-automatic merge commit (or any other commit).

Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
---
 Documentation/githooks.txt        |  7 +++++++
 builtin/merge.c                   | 13 ++++++++++++-
 templates/hooks--pre-merge.sample | 13 +++++++++++++
 3 files changed, 32 insertions(+), 1 deletion(-)
 create mode 100755 templates/hooks--pre-merge.sample
diff --git a/Documentation/githooks.txt b/Documentation/githooks.txt
index b9003fe..3fae643 100644
--- a/Documentation/githooks.txt
+++ b/Documentation/githooks.txt
@@ -86,6 +86,13 @@ All the 'git commit' hooks are invoked with the environment
 variable `GIT_EDITOR=:` if the command will not bring up an editor
 to modify the commit message.
 
+pre-merge
+~~~~~~~~~
+
+This hook is invoked by 'git merge' when doing an automatic merge
+commit; it is equivalent to 'pre-commit' for a non-automatic commit
+for a merge.
+
 prepare-commit-msg
 ~~~~~~~~~~~~~~~~~~
 
diff --git a/builtin/merge.c b/builtin/merge.c
index 0ec8f0d..7c09e0b 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -898,12 +898,23 @@ static void prepare_to_commit(struct commit_list *remoteheads)
 {
 	struct strbuf msg = STRBUF_INIT;
 	const char *comment = _(merge_editor_comment);
+	const char *index_file = get_index_file();
+
+	if (run_hook(index_file, "pre-merge", NULL))
+		abort_commit(remoteheads, NULL);
+	/*
+	 * Re-read the index as pre-merge hook could have updated it,
+	 * and write it out as a tree.  We must do this before we invoke
+	 * the editor and after we invoke run_status above.
+	 */
+	discard_cache();
+	read_cache_from(index_file);
 	strbuf_addbuf(&msg, &merge_msg);
 	strbuf_addch(&msg, '\n');
 	if (0 < option_edit)
 		strbuf_add_lines(&msg, "# ", comment, strlen(comment));
 	write_merge_msg(&msg);
-	run_hook(get_index_file(), "prepare-commit-msg",
+	run_hook(index_file, "prepare-commit-msg",
 		 git_path("MERGE_MSG"), "merge", NULL, NULL);
 	if (0 < option_edit) {
 		if (launch_editor(git_path("MERGE_MSG"), NULL, NULL))
diff --git a/templates/hooks--pre-merge.sample b/templates/hooks--pre-merge.sample
new file mode 100755
index 0000000..a6313e6
--- /dev/null
+++ b/templates/hooks--pre-merge.sample
@@ -0,0 +1,13 @@
+#!/bin/sh
+#
+# An example hook script to verify what is about to be committed.
+# Called by "git merge" with no arguments.  The hook should
+# exit with non-zero status after issuing an appropriate message if
+# it wants to stop the commit.
+#
+# To enable this hook, rename this file to "pre-merge".
+
+. git-sh-setup
+test -x "$GIT_DIR/hooks/pre-commit" &&
+        exec "$GIT_DIR/hooks/pre-commit"
+:
-- 
1.7.12.406.gafd3f81
Previous: Michael J GruberNext: Michael Haggerty
Message 2 of 16 in “pre-merge-hook”
  1. 0/3 pre-merge-hookMichael J Gruber, Sep 5, 2012
  2. 1/3 git-merge: Honor pre-merge hookMichael J Gruber, Sep 5, 2012
  3. Michael HaggertySep 5, 2012
  4. Michael J GruberSep 6, 2012
  5. Michael HaggertySep 6, 2012
  6. 0/4 pre-commit hook for mergesMichael J Gruber, Sep 6, 2012
  7. 1/4 merge: document prepare-commit-msg hook usageMichael J Gruber, Sep 6, 2012
  8. 2/4 git-merge: Honor pre-commit hook based on configMichael J Gruber, Sep 6, 2012
  9. 3/4 merge: --no-verify to bypass pre-commit hookMichael J Gruber, Sep 6, 2012
  10. 4/4 t7503: add tests for pre-commit hook (merge)Michael J Gruber, Sep 6, 2012
  11. 2/3 merge: --no-verify to bypass pre-merge hookMichael J Gruber, Sep 5, 2012
  12. 3/3 t7503: add tests for pre-merge-hookMichael J Gruber, Sep 5, 2012
  13. Junio C HamanoSep 6, 2012
  14. Michael J GruberSep 6, 2012
  15. Junio C HamanoSep 6, 2012
  16. Michael J GruberSep 7, 2012

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