ci: harden parallel-fetch error surfacing and tighten skip clauses

Follow-ups to the parallel-fetch and npm-skip changes:

**Build React App step**
- `set -euo pipefail` so any step (including the backgrounded fetch
  surfaced via `wait`) aborts cleanly instead of continuing into
  `make build` with partial inputs.
- Redirect `prep-translations` output to a logfile and replay it
  after `wait` returns, so its `--- :section:` markers don't
  interleave with `npm ci`'s and confuse Buildkite log folding.
  Replay happens unconditionally so a failed fetch surfaces its log
  before `set -e` aborts.

**Makefile**
- `npm-dependencies` switches from "drop direct-invocation-force"
  to an explicit `_RECURSIVE_INVOKE=1` sentinel passed by `build`'s
  recipe. Preserves the user-facing "make npm-dependencies installs
  even if node_modules exists" behaviour while still letting the
  recursive call short-circuit.
- `prep-translations` skip clause now requires both `dist/` *and*
  `src/translations/` populated. A stale `dist/` paired with an
  empty `src/translations/` would otherwise silently produce a
  no-translations rebuild on `REFRESH_JS_BUILD=1`.

**Housekeeping**
- `.gitignore`: add `dist.tar.gz` (created locally when testing the
  artifact pack/upload step).
- `bin/prep-translations.js`: comment now references `.nvmrc` for
  the Node version it relies on.

Author: jkmassel

.buildkite/pipeline.yml

@@ -8,15 +8,32 @@ steps:
     - label: ':react: Build React App'
       key: build-react
       command: |
+          # Fail fast if any step (including the backgrounded
+          # `prep-translations`, surfaced via `wait`) returns non-zero,
+          # rather than continuing into `make build` with partial inputs.
+          set -euo pipefail
           # `prep-translations` is pure network I/O and no longer depends
           # on `node_modules` (uses Node's built-in `fetch`), so it can run
           # in parallel with `npm ci`. Vite reads `src/translations/` when
           # it emits locale bundles, so we wait for the fetch to complete
           # before invoking `make build`.
-          make prep-translations STRICT_L10N=1 &
+          #
+          # Background output is redirected to a logfile and replayed
+          # after `wait` returns so its `--- :section:` markers don't
+          # interleave with `npm ci`'s and confuse Buildkite log folding.
+          # The replay happens unconditionally so a failed fetch surfaces
+          # its log before `set -e` aborts the script.
+          make prep-translations STRICT_L10N=1 > prep-translations.log 2>&1 &
           PREP_PID=$$!
           make npm-dependencies
-          wait $$PREP_PID
+          PREP_STATUS=0
+          wait $$PREP_PID || PREP_STATUS=$$?
+          echo "--- :earth_americas: prep-translations (ran in parallel with npm ci)"
+          cat prep-translations.log
+          rm -f prep-translations.log
+          if [ "$$PREP_STATUS" -ne 0 ]; then
+              exit "$$PREP_STATUS"
+          fi
           make build REFRESH_JS_BUILD=1
           tar -czf dist.tar.gz dist/
           buildkite-agent artifact upload dist.tar.gz

.gitignore

@@ -136,6 +136,7 @@ out
 # Nuxt.js build / generate output
 .nuxt
 dist
+dist.tar.gz
 
 # Gatsby files
 .cache/

Makefile

@@ -31,14 +31,14 @@ npm-dependencies: ## Install npm dependencies
 # Skip unless...
 # - node_modules doesn't exist
 # - REFRESH_DEPS is set to true or 1
+# - npm-dependencies was invoked directly (not from a recursive `$(MAKE)`)
 #
-# Direct invocation no longer force-installs: `build` invokes this via
-# `$(MAKE) npm-dependencies` from inside its rebuild branch, which sets
-# MAKECMDGOALS=npm-dependencies in the child make. Without this change,
-# that recursive call would re-run `npm ci` even when node_modules is
-# already populated. Users who want to force a reinstall can pass
-# REFRESH_DEPS=1.
-	@if [ ! -d "node_modules" ] || [ "$(REFRESH_DEPS)" = "true" ] || [ "$(REFRESH_DEPS)" = "1" ]; then \
+# `build`'s rebuild branch invokes this as `$(MAKE) _RECURSIVE_INVOKE=1
+# npm-dependencies`, which sets MAKECMDGOALS=npm-dependencies in the
+# child make. Without the sentinel, that recursive call would treat
+# itself as a "direct invocation" and re-run `npm ci` every time `build`
+# rebuilds — even when node_modules is already populated.
+	@if [ ! -d "node_modules" ] || [ "$(REFRESH_DEPS)" = "true" ] || [ "$(REFRESH_DEPS)" = "1" ] || { [ -z "$(_RECURSIVE_INVOKE)" ] && echo "$(MAKECMDGOALS)" | grep -q "^npm-dependencies$$"; }; then \
 		echo "--- :npm: Installing NPM Dependencies"; \
 		npm ci; \
 	else \
@@ -47,18 +47,24 @@ npm-dependencies: ## Install npm dependencies
 
 .PHONY: prep-translations
 prep-translations: ## Fetch and cache locale string files
-# Skip when `dist/` already exists — translations are baked into the
-# bundle at JS build time, so there is nothing for a downstream consumer
-# to refresh until the bundle itself is rebuilt. This matters on CI
-# agents that download `dist.tar.gz` from an upstream job: without it,
-# every downstream `make` target that depends on `build` would re-fetch
-# all ~50 locales from translate.wordpress.org.
+# Skip when `dist/` already exists *and* `src/translations/` is
+# populated — translations are baked into the bundle at JS build time,
+# so there is nothing for a downstream consumer to refresh until the
+# bundle itself is rebuilt. This matters on CI agents that download
+# `dist.tar.gz` from an upstream job: without it, every downstream
+# `make` target that depends on `build` would re-fetch all ~50 locales
+# from translate.wordpress.org.
+#
+# We also require `src/translations/` to be populated so that a stale
+# `dist/` paired with an empty `src/translations/` doesn't silently
+# produce a no-translations rebuild when `REFRESH_JS_BUILD=1` or a
+# direct `make build` triggers JS rebuilding against empty inputs.
 #
 # Otherwise, skip unless...
 # - src/translations doesn't contain any fetched bundles (only `.gitkeep` is committed)
 # - REFRESH_L10N is set to true or 1
 # - prep-translations was invoked directly
-	@if [ -d "dist" ] && [ "$(REFRESH_L10N)" != "true" ] && [ "$(REFRESH_L10N)" != "1" ] && ! echo "$(MAKECMDGOALS)" | grep -q "^prep-translations$$"; then \
+	@if [ -d "dist" ] && [ -n "$$(find src/translations -maxdepth 1 -name '*.json' -print -quit 2>/dev/null)" ] && [ "$(REFRESH_L10N)" != "true" ] && [ "$(REFRESH_L10N)" != "1" ] && ! echo "$(MAKECMDGOALS)" | grep -q "^prep-translations$$"; then \
 		echo "--- :white_check_mark: Skipping translations fetch (dist/ already built, translations baked in). Use REFRESH_L10N=1 to force refresh."; \
 	elif [ -z "$$(find src/translations -maxdepth 1 -name '*.json' -print -quit 2>/dev/null)" ] || [ "$(REFRESH_L10N)" = "true" ] || [ "$(REFRESH_L10N)" = "1" ] || echo "$(MAKECMDGOALS)" | grep -q "^prep-translations$$"; then \
 		echo "--- :npm: Preparing Translations"; \
@@ -123,7 +129,7 @@ build: prep-translations ## Build the project for all platforms (iOS, Android, w
 # `e2e-dependencies`, `lint-js`, `test-js`, etc.) declare
 # `npm-dependencies` as their own prereq.
 	@if [ ! -d "dist" ] || [ "$(REFRESH_JS_BUILD)" = "true" ] || [ "$(REFRESH_JS_BUILD)" = "1" ] || echo "$(MAKECMDGOALS)" | grep -q "^build$$"; then \
-		$(MAKE) npm-dependencies && \
+		$(MAKE) _RECURSIVE_INVOKE=1 npm-dependencies && \
 		echo "--- :node: Building Gutenberg" && \
 		npm run build && \
 		echo "--- :open_file_folder: Copying Build Products into place" && \

bin/prep-translations.js

@@ -9,9 +9,9 @@ import path from 'path';
  */
 import { info, error, debug } from '../src/utils/logger.js';
 
-// Uses Node's built-in `fetch` (Node 18+) so this script can run before
-// `npm ci` has populated `node_modules` — letting CI overlap translation
-// fetching with dependency installation on the critical path.
+// Uses Node's built-in `fetch` (Node 20, per .nvmrc) so this script can
+// run before `npm ci` has populated `node_modules` — letting CI overlap
+// translation fetching with dependency installation on the critical path.
 
 const TRANSLATIONS_DIR = path.join( process.cwd(), 'src/translations' );
 const SUPPORTED_LOCALES = [