Merge branch 'jk/pull-into-dirty-unborn'

"git pull" into nothing trashed "local changes" that were in the
index, and this avoids it.

* jk/pull-into-dirty-unborn:
pull: merge into unborn by fast-forwarding from empty tree
pull: update unborn branch tip after index

diff --git a/git-pull.sh b/git-pull.sh
index 638aabb7b347e2afeb9bf327902de9e3702cd9d4..6828e2c7157fd80905e864b475c11ccc7a330e03 100755 (executable)
--- a/git-pull.sh
+++ b/git-pull.sh
@@ -266,10 +266,17 @@ case "$merge_head" in
        ;;
 esac
 
+# Pulling into unborn branch: a shorthand for branching off
+# FETCH_HEAD, for lazy typers.
 if test -z "$orig_head"
 then
-       git update-ref -m "initial pull" HEAD $merge_head "$curr_head" &&
-       git read-tree -m -u HEAD || exit 1
+       # Two-way merge: we claim the index is based on an empty tree,
+       # and try to fast-forward to HEAD.  This ensures we will not
+       # lose index/worktree changes that the user already made on
+       # the unborn branch.
+       empty_tree=4b825dc642cb6eb9a060e54bf8d69288fbee4904
+       git read-tree -m -u $empty_tree $merge_head &&
+       git update-ref -m "initial pull" HEAD $merge_head "$curr_head"
        exit
 fi
 

diff --git a/t/t5520-pull.sh b/t/t5520-pull.sh
index 6af6c63350383e049082e61d3c8133af79d5a749..ed4d9c83181bc45456074f053ed5a0f137fc7e27 100755 (executable)
--- a/t/t5520-pull.sh
+++ b/t/t5520-pull.sh
@@ -57,6 +57,35 @@ test_expect_success 'pulling into void does not overwrite untracked files' '
        )
 '
 
+test_expect_success 'pulling into void does not overwrite staged files' '
+       git init cloned-staged-colliding &&
+       (
+               cd cloned-staged-colliding &&
+               echo "alternate content" >file &&
+               git add file &&
+               test_must_fail git pull .. master &&
+               echo "alternate content" >expect &&
+               test_cmp expect file &&
+               git cat-file blob :file >file.index &&
+               test_cmp expect file.index
+       )
+'
+
+
+test_expect_success 'pulling into void does not remove new staged files' '
+       git init cloned-staged-new &&
+       (
+               cd cloned-staged-new &&
+               echo "new tracked file" >newfile &&
+               git add newfile &&
+               git pull .. master &&
+               echo "new tracked file" >expect &&
+               test_cmp expect newfile &&
+               git cat-file blob :newfile >newfile.index &&
+               test_cmp expect newfile.index
+       )
+'
+
 test_expect_success 'test . as a remote' '
 
        git branch copy master &&