[PATCH 1/3] format-patch: document and exercise that -o does only create the trailing directory

[Bert Wesarg]

Signed-off-by: Bert Wesarg <bert.wes...@googlemail.com>
---
 Documentation/config/format.txt    |  3 ++-
 Documentation/git-format-patch.txt |  4 +++-
 t/t4014-format-patch.sh            | 16 ++++++++++++++++
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/Documentation/config/format.txt b/Documentation/config/format.txt
index 414a5a8a9d..e17c5d6b0f 100644
--- a/Documentation/config/format.txt
+++ b/Documentation/config/format.txt
@@ -80,7 +80,8 @@ format.coverLetter::
 
 format.outputDirectory::
        Set a custom directory to store the resulting files instead of the
-       current working directory.
+       current working directory. Only the trailing directory will be created
+       though.
 
 format.useAutoBase::
        A boolean value which lets you enable the `--base=auto` option of
diff --git a/Documentation/git-format-patch.txt 
b/Documentation/git-format-patch.txt
index b9b97e63ae..fe7492353e 100644
--- a/Documentation/git-format-patch.txt
+++ b/Documentation/git-format-patch.txt
@@ -66,7 +66,9 @@ they are created in the current working directory. The 
default path
 can be set with the `format.outputDirectory` configuration option.
 The `-o` option takes precedence over `format.outputDirectory`.
 To store patches in the current working directory even when
-`format.outputDirectory` points elsewhere, use `-o .`.
+`format.outputDirectory` points elsewhere, use `-o .`. Note that only
+the trailing directory will be created by Git, leading directories must
+already exists.
 
 By default, the subject of a single patch is "[PATCH] " followed by
 the concatenation of lines from the commit message up to the first blank
diff --git a/t/t4014-format-patch.sh b/t/t4014-format-patch.sh
index ca7debf1d4..bf2715a503 100755
--- a/t/t4014-format-patch.sh
+++ b/t/t4014-format-patch.sh
@@ -1632,6 +1632,22 @@ test_expect_success 'From line has expected format' '
        test_cmp from filtered
 '
 
+test_expect_success 'format-patch -o with no leading directories' '
+       rm -fr patches &&
+       git format-patch -o patches master..side &&
+       test $(git rev-list master..side | wc -l) -eq $(ls patches | wc -l)
+'
+
+test_expect_success 'format-patch -o with leading existing directories' '
+       git format-patch -o patches/side master..side &&
+       test $(git rev-list master..side | wc -l) -eq $(ls patches/side | wc -l)
+'
+
+test_expect_failure 'format-patch -o with leading non-existing directories' '
+       rm -fr patches &&
+       git format-patch -o patches/side master..side
+'
+
 test_expect_success 'format-patch format.outputDirectory option' '
        test_config format.outputDirectory patches &&
        rm -fr patches &&
-- 
2.23.0.11.g242cf7f110