allow pull --rebase on branch yet to be born

When doing a "pull --rebase", we check to make sure that the index and
working tree are clean. The index-clean check compares the index against
HEAD. The test erroneously reports dirtiness if we don't have a HEAD yet.

In such an "unborn branch" case, by definition, a non-empty index won't
be based on whatever we are pulling down from the remote, and will lose
the local change.  Just check if $GIT_DIR/index exists and error out.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/git-pull.sh b/git-pull.sh
index 0f24182974fe2040c950b846decf360c1c22dbb1..0bbd5bf7df185acd24302f9e5ce06e4a314d040a 100755 (executable)
--- a/git-pull.sh
+++ b/git-pull.sh
@@ -119,11 +119,19 @@ error_on_no_merge_candidates () {
 }
 
 test true = "$rebase" && {
-       git update-index --ignore-submodules --refresh &&
-       git diff-files --ignore-submodules --quiet &&
-       git diff-index --ignore-submodules --cached --quiet HEAD -- ||
-       die "refusing to pull with rebase: your working tree is not up-to-date"
-
+       if ! git rev-parse -q --verify HEAD >/dev/null
+       then
+               # On an unborn branch
+               if test -f "$GIT_DIR/index"
+               then
+                       die "updating an unborn branch with changes added to the index"
+               fi
+       else
+               git update-index --ignore-submodules --refresh &&
+               git diff-files --ignore-submodules --quiet &&
+               git diff-index --ignore-submodules --cached --quiet HEAD -- ||
+               die "refusing to pull with rebase: your working tree is not up-to-date"
+       fi
        oldremoteref= &&
        . git-parse-remote &&
        remoteref="$(get_remote_merge_branch "$@" 2>/dev/null)" &&

diff --git a/t/t5520-pull.sh b/t/t5520-pull.sh
index e78d40242a80d9b2aa74e74d3a4aecddbb63ab99..dd2ee842e020c23b49ed4e2070c4e31cdb7ac055 100755 (executable)
--- a/t/t5520-pull.sh
+++ b/t/t5520-pull.sh
@@ -149,4 +149,15 @@ test_expect_success 'pull --rebase dies early with dirty working directory' '
 
 '
 
+test_expect_success 'pull --rebase works on branch yet to be born' '
+       git rev-parse master >expect &&
+       mkdir empty_repo &&
+       (cd empty_repo &&
+        git init &&
+        git pull --rebase .. master &&
+        git rev-parse HEAD >../actual
+       ) &&
+       test_cmp expect actual
+'
+
 test_done