Merge branch 'am/stash-branch'

* am/stash-branch:
  Add a test for "git stash branch"
  Implement "git stash branch <newbranch> <stash>"

3 files changed, 99 insertions, 1 deletions

diff --git a/Documentation/git-stash.txt b/Documentation/git-stash.txt
index e42c5eff4..7d50d74cc 100644
--- a/Documentation/git-stash.txt
+++ b/Documentation/git-stash.txt
@@ -8,8 +8,11 @@ git-stash - Stash the changes in a dirty working directory away
 SYNOPSIS
 --------
 [verse]
-'git stash' (list | show [<stash>] | apply [<stash>] | clear | drop [<stash>] | pop [<stash>])
+'git stash' list
+'git stash' (show | apply | drop | pop ) [<stash>]
+'git stash' branch <branchname> [<stash>]
 'git stash' [save [<message>]]
+'git stash' clear
 
 DESCRIPTION
 -----------
@@ -84,6 +87,20 @@ tree's changes, but also the index's ones. However, this can fail, when you
 have conflicts (which are stored in the index, where you therefore can no
 longer apply the changes as they were originally).
 
+branch <branchname> [<stash>]::
+
+	Creates and checks out a new branch named `<branchname>` starting from
+	the commit at which the `<stash>` was originally created, applies the
+	changes recorded in `<stash>` to the new working tree and index, then
+	drops the `<stash>` if that completes successfully. When no `<stash>`
+	is given, applies the latest one.
++
+This is useful if the branch on which you ran `git stash save` has
+changed enough that `git stash apply` fails due to conflicts. Since
+the stash is applied on top of the commit that was HEAD at the time
+`git stash` was run, it restores the originally stashed state with
+no conflicts.
+
 clear::
 	Remove all the stashed states. Note that those states will then
 	be subject to pruning, and may be difficult or impossible to recover.
diff --git a/git-stash.sh b/git-stash.sh
index 92531a295..e4cb6c3e4 100755
--- a/git-stash.sh
+++ b/git-stash.sh
@@ -233,6 +233,23 @@ drop_stash () {
 	git rev-parse --verify "$ref_stash@{0}" > /dev/null 2>&1 || clear_stash
 }
 
+apply_to_branch () {
+	have_stash || die 'Nothing to apply'
+
+	test -n "$1" || die 'No branch name specified'
+	branch=$1
+
+	if test -z "$2"
+	then
+		set x "$ref_stash@{0}"
+	fi
+	stash=$2
+
+	git-checkout -b $branch $stash^ &&
+	apply_stash --index $stash &&
+	drop_stash $stash
+}
+
 # Main command set
 case "$1" in
 list)
@@ -279,6 +296,10 @@ pop)
 		drop_stash "$@"
 	fi
 	;;
+branch)
+	shift
+	apply_to_branch "$@"
+	;;
 *)
 	if test $# -eq 0
 	then
diff --git a/t/t3903-stash.sh b/t/t3903-stash.sh
index 54d99ed0c..8d4804b65 100755
--- a/t/t3903-stash.sh
+++ b/t/t3903-stash.sh
@@ -117,4 +117,64 @@ test_expect_success 'stash pop' '
 	test 0 = $(git stash list | wc -l)
 '
 
+cat > expect << EOF
+diff --git a/file2 b/file2
+new file mode 100644
+index 0000000..1fe912c
+--- /dev/null
++++ b/file2
+@@ -0,0 +1 @@
++bar2
+EOF
+
+cat > expect1 << EOF
+diff --git a/file b/file
+index 257cc56..5716ca5 100644
+--- a/file
++++ b/file
+@@ -1 +1 @@
+-foo
++bar
+EOF
+
+cat > expect2 << EOF
+diff --git a/file b/file
+index 7601807..5716ca5 100644
+--- a/file
++++ b/file
+@@ -1 +1 @@
+-baz
++bar
+diff --git a/file2 b/file2
+new file mode 100644
+index 0000000..1fe912c
+--- /dev/null
++++ b/file2
+@@ -0,0 +1 @@
++bar2
+EOF
+
+test_expect_success 'stash branch' '
+	echo foo > file &&
+	git commit file -m first
+	echo bar > file &&
+	echo bar2 > file2 &&
+	git add file2 &&
+	git stash &&
+	echo baz > file &&
+	git commit file -m second &&
+	git stash branch stashbranch &&
+	test refs/heads/stashbranch = $(git symbolic-ref HEAD) &&
+	test $(git rev-parse HEAD) = $(git rev-parse master^) &&
+	git diff --cached > output &&
+	test_cmp output expect &&
+	git diff > output &&
+	test_cmp output expect1 &&
+	git add file &&
+	git commit -m alternate\ second &&
+	git diff master..stashbranch > output &&
+	test_cmp output expect2 &&
+	test 0 = $(git stash list | wc -l)
+'
+
 test_done