[buildkite] Fix backport PR pipeline generation (#100427) (#100430)

(cherry picked from commit f4d53bc) # Conflicts: # .buildkite/scripts/pull-request/pipeline.ts
elastic · Oct 6, 2023 · 71f5f2d · 71f5f2d
1 parent 774e3bf
commit 71f5f2d
Showing 1 changed file with 4 additions and 3 deletions.
diff --git a/.buildkite/scripts/pull-request/pipeline.ts b/.buildkite/scripts/pull-request/pipeline.ts
@@ -116,9 +116,10 @@ export const generatePipelines = (
     .filter((x) => x);
 
   if (!changedFiles?.length) {
-    const mergeBase = execSync(`git merge-base origin/${process.env["GITHUB_PR_TARGET_BRANCH"]} HEAD`, {
-      cwd: PROJECT_ROOT,
-    })
+    const mergeBase = execSync(
+      `git fetch origin ${process.env["GITHUB_PR_TARGET_BRANCH"]}; git merge-base origin/${process.env["GITHUB_PR_TARGET_BRANCH"]} HEAD`,
+      { cwd: PROJECT_ROOT }
+    )
       .toString()
       .trim();