am: ignore leading whitespace before patch

Some web-based email clients prepend whitespace to raw message
transcripts to workaround content-sniffing in some browsers.  Adjust
the patch format detection logic to ignore leading whitespace.

So now you can apply patches from GMail with "git am" in three steps:

 1. choose "show original"
 2. tell the browser to "save as" (for example by pressing Ctrl+S)
 3. run "git am" on the saved file

This fixes a regression introduced by v1.6.4-rc0~15^2~2 (git-am
foreign patch support: autodetect some patch formats, 2009-05-27).
GMail support was first introduced to "git am" by v1.5.4-rc0~274^2
(Make mailsplit and mailinfo strip whitespace from the start of the
input, 2007-11-01).

Signed-off-by: David Barr <davidbarr@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/git-am.sh b/git-am.sh
index 463c741dfc259927b4429f19972ced21d87c215e..c8422dbe6e54fc2e2d2648dbbf39af94f0bd8d70 100755 (executable)
--- a/git-am.sh
+++ b/git-am.sh
@@ -196,10 +196,15 @@ check_patch_format () {
                return 0
        fi
 
-       # otherwise, check the first few lines of the first patch to try
-       # to detect its format
+       # otherwise, check the first few non-blank lines of the first
+       # patch to try to detect its format
        {
-               read l1
+               # Start from first line containing non-whitespace
+               l1=
+               while test -z "$l1"
+               do
+                       read l1
+               done
                read l2
                read l3
                case "$l1" in

diff --git a/t/t4150-am.sh b/t/t4150-am.sh
index 151404e0908c55f3c0d399d03225b077dc226562..d7d9ccc1c8c31ef3b2d4763532344d0637a18b5c 100755 (executable)
--- a/t/t4150-am.sh
+++ b/t/t4150-am.sh
@@ -96,6 +96,13 @@ test_expect_success setup '
                echo "X-Fake-Field: Line Three" &&
                git format-patch --stdout first | sed -e "1d"
        } | append_cr >patch1-crlf.eml &&
+       {
+               printf "%255s\\n" ""
+               echo "X-Fake-Field: Line One" &&
+               echo "X-Fake-Field: Line Two" &&
+               echo "X-Fake-Field: Line Three" &&
+               git format-patch --stdout first | sed -e "1d"
+       } > patch1-ws.eml &&
 
        sed -n -e "3,\$p" msg >file &&
        git add file &&
@@ -167,6 +174,17 @@ test_expect_success 'am applies patch e-mail not in a mbox with CRLF' '
        test "$(git rev-parse second^)" = "$(git rev-parse HEAD^)"
 '
 
+test_expect_success 'am applies patch e-mail with preceding whitespace' '
+       rm -fr .git/rebase-apply &&
+       git reset --hard &&
+       git checkout first &&
+       git am patch1-ws.eml &&
+       ! test -d .git/rebase-apply &&
+       git diff --exit-code second &&
+       test "$(git rev-parse second)" = "$(git rev-parse HEAD)" &&
+       test "$(git rev-parse second^)" = "$(git rev-parse HEAD^)"
+'
+
 test_expect_success 'setup: new author and committer' '
        GIT_AUTHOR_NAME="Another Thor" &&
        GIT_AUTHOR_EMAIL="a.thor@example.com" &&