From 6b29db73bed2e47a46e91bdc4b4c87b9d97c7b66 Mon Sep 17 00:00:00 2001
From: Zoltan Kochan <z@kochan.io>
Date: Wed, 19 Aug 2026 16:08:47 +0200
Subject: [PATCH] fix: create the cache dir before symlinking the re-warm
 project at it
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The re-warm broke the weekly run on its first outing, on pnpm 11: the
cache directory is deleted two rows before update, and a manager whose
`node_modules` row is a registry-free no-op — pnpm restores the tree
from the lockfile copy inside it — never recreates it. The re-warm's
`cache` symlink then points at nothing, and the warm-up install dies
with ENOTDIR trying to mkdir its store through a dangling link. The
smoke test missed it because pnpm 12 reaches the cache through absolute
environment paths rather than the symlink, and Bun's re-downloading
`node_modules` row recreates the directory — pnpm 11 is the manager
that goes through the symlink AND skips the re-download. The directory
is now created (idempotently) before the symlink, and the pnpm 11 chain
runs clean end to end: its update lands at 1.8s against the 7.5s the
cold-cache artifact used to charge it.

Also: when every measuring job fails, the report job's samples
directory never comes into existence, and merge-results died with a raw
ENOENT scandir instead of its own explanation. A missing directory is
the same situation as an empty one and now gets the same error.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
---
 benchmarkFixture.js |  6 ++++++
 mergeResults.js     | 13 ++++++++++++-
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/benchmarkFixture.js b/benchmarkFixture.js
index 7100b5f..dc85c31 100644
--- a/benchmarkFixture.js
+++ b/benchmarkFixture.js
@@ -406,6 +406,12 @@ export default async function benchmark (pm, fixture, opts) {
         if (err?.code !== 'ENOENT') throw err
       }
     }
+    // The cache dir may not exist right now: it was deleted two rows up, and
+    // a manager whose `node_modules` row is a registry-free no-op (pnpm
+    // restores the tree from the lockfile copy inside it) never recreated
+    // it. A symlink to a path that isn't there is dangling, and the warm-up
+    // install fails trying to mkdir its store through it.
+    await fs.mkdir(path.join(cwd, 'cache'), { recursive: true })
     await fs.symlink(path.join(cwd, 'cache'), path.join(rewarmDir, 'cache'), 'dir')
     measureInstall(pm, rewarmDir, env)
   } finally {
diff --git a/mergeResults.js b/mergeResults.js
index b311b36..a40be88 100644
--- a/mergeResults.js
+++ b/mergeResults.js
@@ -47,7 +47,18 @@ async function main () {
   if (!samplesDir) {
     throw new Error('Usage: node mergeResults.js <dir containing one subdirectory per run>')
   }
-  const runDirs = fs.readdirSync(samplesDir, { withFileTypes: true })
+  // A samples directory that doesn't exist means no measuring job uploaded
+  // anything — every one of them failed. That is the same situation as an
+  // empty directory, and it deserves the same explanation rather than a raw
+  // ENOENT from `readdirSync`.
+  let entries
+  try {
+    entries = fs.readdirSync(samplesDir, { withFileTypes: true })
+  } catch (err) {
+    if (err.code !== 'ENOENT') throw err
+    entries = []
+  }
+  const runDirs = entries
     .filter((entry) => entry.isDirectory())
     // Sorted so that a merge of the same runs always produces the same file,
     // whatever order the artifacts happened to be downloaded in.