pull: add pull.ff configuration

Add a `pull.ff` configuration option that is analogous
to the `merge.ff` option.

This allows us to control the fast-forward behavior for
pull-initiated merges only.

Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/config.txt b/Documentation/config.txt
index ab26963d61877a2f8e03a3532ace5b31bc68738e..7443f15bf4dea55cf3735cd9d75b0dcfd0bb3743 100644 (file)
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -1877,6 +1877,16 @@ pretty.<name>::
        Note that an alias with the same name as a built-in format
        will be silently ignored.
 
+pull.ff::
+       By default, Git does not create an extra merge commit when merging
+       a commit that is a descendant of the current commit. Instead, the
+       tip of the current branch is fast-forwarded. When set to `false`,
+       this variable tells Git to create an extra merge commit in such
+       a case (equivalent to giving the `--no-ff` option from the command
+       line). When set to `only`, only such fast-forward merges are
+       allowed (equivalent to giving the `--ff-only` option from the
+       command line).
+
 pull.rebase::
        When true, rebase branches on top of the fetched branch, instead
        of merging the default branch from the default remote when "git

diff --git a/git-pull.sh b/git-pull.sh
index b946fd975bacae7b73645e0dba8ae61da716ccfc..44b792a5d2007d89d1735d1d114e439c3d365d99 100755 (executable)
--- a/git-pull.sh
+++ b/git-pull.sh
@@ -52,6 +52,21 @@ if test -z "$rebase"
 then
        rebase=$(bool_or_string_config pull.rebase)
 fi
+
+# Setup default fast-forward options via `pull.ff`
+pull_ff=$(git config pull.ff)
+case "$pull_ff" in
+false)
+       no_ff=--no-ff
+       break
+       ;;
+only)
+       ff_only=--ff-only
+       break
+       ;;
+esac
+
+
 dry_run=
 while :
 do

diff --git a/t/t7601-merge-pull-config.sh b/t/t7601-merge-pull-config.sh
index 830a4c3e9dffc7963dda03139be6c4e66fddf10f..f768c900abd1cddc6d69a1bdeae897374e7d0dad 100755 (executable)
--- a/t/t7601-merge-pull-config.sh
+++ b/t/t7601-merge-pull-config.sh
@@ -38,6 +38,27 @@ test_expect_success 'merge c1 with c2' '
        test -f c2.c
 '
 
+test_expect_success 'fast-forward pull succeeds with "true" in pull.ff' '
+       git reset --hard c0 &&
+       test_config pull.ff true &&
+       git pull . c1 &&
+       test "$(git rev-parse HEAD)" = "$(git rev-parse c1)"
+'
+
+test_expect_success 'fast-forward pull creates merge with "false" in pull.ff' '
+       git reset --hard c0 &&
+       test_config pull.ff false &&
+       git pull . c1 &&
+       test "$(git rev-parse HEAD^1)" = "$(git rev-parse c0)" &&
+       test "$(git rev-parse HEAD^2)" = "$(git rev-parse c1)"
+'
+
+test_expect_success 'pull prevents non-fast-forward with "only" in pull.ff' '
+       git reset --hard c1 &&
+       test_config pull.ff only &&
+       test_must_fail git pull . c3
+'
+
 test_expect_success 'merge c1 with c2 (ours in pull.twohead)' '
        git reset --hard c1 &&
        git config pull.twohead ours &&