fix(bench): pin composer binary and work around HTTP/3 slowdown

Benchmarks were comparing against whatever composer happened to be on
PATH instead of the pinned submodule version, and paid the HTTP/3
fallback penalty from composer/composer#12987 on every packagist
request.

1 files changed, 7 insertions, 0 deletions

diff --git a/scripts/bench/lib.sh b/scripts/bench/lib.sh
new file mode 100755
index 00000000..a4fa78ab
--- /dev/null
+++ b/scripts/bench/lib.sh
@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+
+# Work around https://github.com/composer/composer/issues/12987:
+apply_http3_workaround() {
+  git -C "$REPO_ROOT/composer" apply "$REPO_ROOT/scripts/bench/disable-http3.patch"
+  trap 'git -C "$REPO_ROOT/composer" restore -- src/Composer/Util/Http/CurlDownloader.php' EXIT
+}