ci: assert yarn prints no warnings (#5565)

* Assert in CI yarn prints no warnings

* Add exit 1

.github/workflows/test.yml

@@ -53,6 +53,9 @@ jobs:
           path: packages/validator/spec-tests
           key: spec-test-data-${{ hashFiles('packages/validator/test/spec/params.ts') }}
 
+      - name: Assert yarn prints no warnings
+        run: scripts/assert_no_yarn_warnings.sh
+
       # Misc sanity checks
       - name: Lint Grafana dashboards
         run: scripts/validate-grafana-dashboards.sh

scripts/assert_no_yarn_warnings.sh

@@ -0,0 +1,14 @@
+#!/bin/bash
+
+# run yarn install --check-files, capturing stderr
+OUTPUT=$(yarn install --check-files 2>&1)
+
+echo $OUTPUT
+
+# grep the output for 'warning'
+if echo "$OUTPUT" | grep -qi 'warning'; then
+  echo "There were warnings in yarn install --check-files"
+  exit 1
+else
+  echo "No warnings in yarn install --check-files"
+fi