Test step output

Author: hsubox76

.github/workflows/check-changeset.yml

@@ -0,0 +1,25 @@
+name: Check Changeset
+
+on: pull_request
+
+jobs:
+  check_changeset:
+    name: Check changeset vs changed files
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Checkout
+      run: |
+        git fetch --no-tags --prune --depth=1 origin +refs/heads/*:refs/remotes/origin/*
+    - name: Set up Node (10)
+      uses: actions/setup-node@v1
+      with:
+        node-version: 10.x
+    - name: Yarn install
+      run: yarn
+    - name: Run changeset script
+      run: yarn ts-node-script scripts/check_changeset.ts
+      id: check-changeset
+    - name: Read output
+      run: echo env.MISSING_PACKAGES

scripts/check_changeset.ts

@@ -85,7 +85,16 @@ async function main() {
       const missingPackages = changedPackages.filter(
         changedPkg => !changesetPackages.includes(changedPkg)
       );
-      console.log(missingPackages);
+      if (missingPackages.length > 0) {
+        // console.warn(chalk.yellow(`Warning: The following packages were `
+        // + `changed but not added to the changeset file, make sure this was `
+        // + `intentional:\n${missingPackages.join('\n')}`));
+        // process.exit(1);
+        console.log(
+          `::set-env name=MISSING_PACKAGES::${missingPackages.join(',')}`
+        );
+      }
+      process.exit();
     }
   } catch (e) {
     console.error(chalk`{red ${e}}`);