ci(engines): widen engines.node to >=18 in CI to keep Node 18/20 jobs running (#9145)

* ci(engines): widen engines.node to >=18 in CI to keep Node 18/20 jobs running

engines.node is bumped to >=22 to match the supported runtime range. The
runtime guard (packages/dd-trace/src/guardrails/index.js) and the withVersions
test helper both read engines.node and bail when the running major is below it,
so on Node 18/20 every suite would silently skip (withVersions returns early,
the init guard short-circuits, mocha reports 0 passing).

CI widens engines.node back to >=18 at the action level (right after
actions/setup-node) via scripts/ci/widen-engines-for-ci.js, so Node 18/20 jobs
keep exercising real tests. The on-disk package.json that ships is unchanged
(engines.node stays >=22).

Co-authored-by: Cursor <cursoragent@cursor.com>

* ci(engines): only widen engines.node on Node 18/20 jobs

The widen step lives in the shared node/setup action, so it ran on every CI job,
including integration-guardrails-unsupported, which installs Node 0.8 through 14 on
purpose to verify the runtime guard aborts. Two problems: the script used a
node:-prefixed require (unsupported before Node 14.18) so it crashed and failed those
jobs, and even had it run, rewriting engines.node there would undermine a test that
relies on the shipped >=22.

Gate the step in the action so it only runs when the installed major is 18 or 20 (the
supported majors the >=22 bump newly excludes). Every other version, including the
unsupported matrix, keeps the shipped >=22 and the script is never parsed by a runtime
too old to run it.

Co-authored-by: Cursor <cursoragent@cursor.com>

* ci(node): pin oldest alias to Node 18 instead of deriving from engines.node

Commit 1a79e10 (prepare to drop Node 18/20) changed the `oldest` version alias
to read the minimum major out of package.json engines.node. With engines.node now
bumped to >=22, `oldest` resolved to Node 22, which dropped Node 18 from the matrix
and shifted the child_process job's legs to {22,20,24,26}. The resulting leg order
(Node 22 first, then 20) destabilized the Bluebird global-Promise tests on the Node
20 leg, which pass on master's {18,20,24,26}.

Pin `oldest` back to a literal 18 so CI keeps testing the oldest version we still
exercise, decoupled from the shipped engines floor. This restores the matrix and leg
order to match master; the widen step still restores >=18 on the 18/20 legs.

Co-authored-by: Cursor <cursoragent@cursor.com>

* add early return

---------

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: pabloerhard

.github/actions/node/setup/action.yml

@@ -27,8 +27,10 @@ runs:
         }
         case "$VERSION" in
           eol)         version=16 ;;
-          oldest)      oldest_major=$(awk '/"node"/{match($0,/[0-9]+/);print substr($0,RSTART,RLENGTH);exit}' package.json)
-                      version=$(node_version "$oldest_major") ;;
+          # Pinned to 18 rather than derived from package.json engines.node: CI keeps testing the
+          # oldest version we still exercise (18) even though the shipped engines floor is now >=22.
+          # See the Widen engines.node for CI step below, which restores >=18 on the 18/20 legs.
+          oldest)      version=$(node_version 18) ;;
           maintenance) version=$(node_version 20) ;;
           active)      version=$(node_version 24) ;;
           latest)      version=${LATEST_VERSION:-$(node_version 26)}
@@ -44,6 +46,22 @@ runs:
         node-version: ${{ steps.node-version.outputs.version }}
         registry-url: ${{ inputs.registry-url || 'https://registry.npmjs.org' }}
 
+    # The shipped package.json pins engines.node to the supported runtime range, but CI keeps
+    # running the full suite on Node 18/20. Widen the field to >=18 for this checkout so the
+    # runtime guard and the withVersions test helper don't bail and silently skip those jobs.
+    # Gate on the major so this never runs on the ancient runtimes the guardrails-unsupported
+    # job installs (those must keep seeing the shipped >=22 so the guard aborts), and so the
+    # script is only ever parsed by a Node version new enough to run it.
+    - name: Widen engines.node for CI
+      shell: bash
+      run: |
+        MAJOR=$(node -e "process.stdout.write(String(parseInt(process.versions.node)))")
+        if [ "$MAJOR" = "18" ] || [ "$MAJOR" = "20" ]; then
+          node scripts/ci/widen-engines-for-ci.js
+        else
+          echo "Leaving engines.node unchanged on Node $(node -v) (only widened on Node 18/20)."
+        fi
+
     # Persist the resolved version so subsequent runs within this 60-minute window can reuse it.
     - name: Save resolved version
       if: steps.node-version-cache.outputs.cache-hit != 'true'

scripts/ci/widen-engines-for-ci.js

@@ -0,0 +1,35 @@
+#!/usr/bin/env node
+
+'use strict'
+
+// CI-only helper. The shipped package.json pins `engines.node` to the supported
+// runtime range (`>=22`), but CI still runs the full suite on Node 18 and 20 to
+// keep those jobs exercising real tests. The runtime guard
+// (packages/dd-trace/src/guardrails/index.js) and the `withVersions` test helper
+// both read `engines.node` and bail when the running major is below it, which would
+// silently skip every suite on those majors. Widening the field to `>=18` for the
+// CI checkout keeps those jobs honest without touching what we publish.
+//
+// The node/setup action gates this step so it only runs on the supported majors the
+// `>=22` bump newly excludes (18 and 20); it is never invoked on the ancient runtimes
+// the `integration-guardrails-unsupported` job installs, which must keep seeing the
+// shipped `>=22` so the guard aborts.
+
+const fs = require('node:fs')
+const path = require('node:path')
+
+const CI_MIN_NODE = '>=18'
+
+const packageJsonPath = path.join(__dirname, '..', '..', 'package.json')
+const pkg = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'))
+
+const before = pkg.engines.node
+if (before === CI_MIN_NODE) return
+
+pkg.engines.node = CI_MIN_NODE
+const after = pkg.engines.node
+
+fs.writeFileSync(packageJsonPath, JSON.stringify(pkg, null, 2) + '\n')
+
+// eslint-disable-next-line no-console
+console.log(`Widened engines.node for CI: ${before} -> ${after}`)