diff mbox series

[15/30] subtree: use `git merge-base --is-ancestor`

Message ID	20210423194230.1388945-16-lukeshu@lukeshu.com (mailing list archive)
State	Superseded
Headers	show Return-Path: <git-owner@kernel.org> From: Luke Shumaker <lukeshu@lukeshu.com> To: git@vger.kernel.org Cc: Avery Pennarun <apenwarr@gmail.com>, Charles Bailey <cbailey32@bloomberg.net>, Danny Lin <danny0838@gmail.com>, "David A . Greene" <greened@obbligato.org>, David Aguilar <davvid@gmail.com>, Jakub Suder <jakub.suder@gmail.com>, James Denholm <nod.helm@gmail.com>, Jeff King <peff@peff.net>, Jonathan Nieder <jrnieder@gmail.com>, Junio C Hamano <gitster@pobox.com>, =?utf-8?b?Tmd1eeG7hW4gVGjDoWkgTmfhu41j?= =?utf-8?b?IER1eQ==?= <pclouds@gmail.com>, Roger L Strain <roger.strain@swri.org>, Techlive Zheng <techlivezheng@gmail.com>, Luke Shumaker <lukeshu@datawire.io> Subject: [PATCH 15/30] subtree: use `git merge-base --is-ancestor` Date: Fri, 23 Apr 2021 13:42:15 -0600 Message-Id: <20210423194230.1388945-16-lukeshu@lukeshu.com> In-Reply-To: <20210423194230.1388945-1-lukeshu@lukeshu.com> References: <20210423194230.1388945-1-lukeshu@lukeshu.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	subtree: clean up, improve UX \| expand [00/30] subtree: clean up, improve UX [01/30] .gitignore: Ignore /git-subtree [02/30] subtree: t7900: update for having the default branch name be 'main' [03/30] subtree: t7900: use test-lib.sh's test_count [04/30] subtree: t7900: use consistent formatting [05/30] subtree: t7900: comment subtree_test_create_repo [06/30] subtree: t7900: use 'test' for string equality [07/30] subtree: t7900: delete some dead code [08/30] subtree: t7900: fix 'verify one file change per commit' [09/30] subtree: t7900: rename last_commit_message to last_commit_subject [10/30] subtree: t7900: add a test for the -h flag [11/30] subtree: t7900: add porcelain tests for 'pull' and 'push' [12/30] subtree: don't have loose code outside of a function [13/30] subtree: more consistent error propagation [14/30] subtree: drop support for git < 1.7 [15/30] subtree: use `git merge-base --is-ancestor` [16/30] subtree: use git-sh-setup's `say` [17/30] subtree: use more explicit variable names for cmdline args [18/30] subtree: use $* instead of $@ as appropriate [19/30] subtree: give `$(git --exec-path)` precedence over `$PATH` [20/30] subtree: use "^{commit}" instead of "^0" [21/30] subtree: parse revs in individual cmd_ functions [22/30] subtree: remove duplicate check [23/30] subtree: add comments and sanity checks [24/30] subtree: don't let debug and progress output clash [25/30] subtree: have $indent actually affect indentation [26/30] subtree: give the docs a once-over [27/30] subtree: allow --squash to be used with --rejoin [28/30] subtree: allow 'split' flags to be passed to 'push' [29/30] subtree: push: allow specifying a local rev other than HEAD [30/30] subtree: be stricter about validating flags

Commit Message

Luke Shumaker April 23, 2021, 7:42 p.m. UTC

From: Luke Shumaker <lukeshu@datawire.io>

Instead of writing a slow `rev_is_descendant_of_branch $a $b` function
in shell, just use the fast `git merge-base --is-ancestor $b $a`.

Signed-off-by: Luke Shumaker <lukeshu@datawire.io>
---
 contrib/subtree/git-subtree.sh | 16 +---------------
 1 file changed, 1 insertion(+), 15 deletions(-)

diff mbox series

Patch

diff --git a/contrib/subtree/git-subtree.sh b/contrib/subtree/git-subtree.sh
index 4503564f7e..70e16b807b 100755
--- a/contrib/subtree/git-subtree.sh
+++ b/contrib/subtree/git-subtree.sh
@@ -280,20 +280,6 @@  rev_exists () {
 	fi
 }
 
-rev_is_descendant_of_branch () {
-	newrev="$1"
-	branch="$2"
-	branch_hash=$(git rev-parse "$branch")
-	match=$(git rev-list -1 "$branch_hash" "^$newrev")
-
-	if test -z "$match"
-	then
-		return 0
-	else
-		return 1
-	fi
-}
-
 # if a commit doesn't have a parent, this might not work.  But we only want
 # to remove the parent from the rev-list, and since it doesn't exist, it won't
 # be there anyway, so do nothing in that case.
@@ -811,7 +797,7 @@  cmd_split () {
 	then
 		if rev_exists "refs/heads/$branch"
 		then
-			if ! rev_is_descendant_of_branch "$latest_new" "$branch"
+			if ! git merge-base --is-ancestor "$branch" "$latest_new"
 			then
 				die "Branch '$branch' is not an ancestor of commit '$latest_new'."
 			fi