git-p4: add the `p4-pre-submit` hook

The `p4-pre-submit` hook is executed before git-p4 submits code.
If the hook exits with non-zero value, submit process not start.

Signed-off-by: Chen Bin <chenbin.sh@gmail.com>
Reviewed-by: Luke Diamand <luke@diamand.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

2 files changed, 15 insertions, 0 deletions

diff --git a/Documentation/git-p4.txt b/Documentation/git-p4.txt
index f0de3b891b..41780a5aa9 100644
--- a/Documentation/git-p4.txt
+++ b/Documentation/git-p4.txt
@@ -374,6 +374,14 @@ These options can be used to modify 'git p4 submit' behavior.
     been submitted. Implies --disable-rebase. Can also be set with
     git-p4.disableP4Sync. Sync with origin/master still goes ahead if possible.
 
+Hook for submit
+~~~~~~~~~~~~~~~
+The `p4-pre-submit` hook is executed if it exists and is executable.
+The hook takes no parameters and nothing from standard input. Exiting with
+non-zero status from this script prevents `git-p4 submit` from launching.
+
+One usage scenario is to run unit tests in the hook.
+
 Rebase options
 ~~~~~~~~~~~~~~
 These options can be used to modify 'git p4 rebase' behavior.
diff --git a/Documentation/githooks.txt b/Documentation/githooks.txt
index e3c283a174..959044347e 100644
--- a/Documentation/githooks.txt
+++ b/Documentation/githooks.txt
@@ -485,6 +485,13 @@ The exit status determines whether git will use the data from the
 hook to limit its search.  On error, it will fall back to verifying
 all files and folders.
 
+p4-pre-submit
+~~~~~~~~~~~~~
+
+This hook is invoked by `git-p4 submit`. It takes no parameters and nothing
+from standard input. Exiting with non-zero status from this script prevent
+`git-p4 submit` from launching. Run `git-p4 submit --help` for details.
+
 GIT
 ---
 Part of the linkgit:git[1] suite