Check generated files are up-to-date

Author: GromNaN

.github/actions/setup/action.yml

@@ -11,6 +11,9 @@ inputs:
     description: "INI values to pass along to setup-php action"
     required: false
     default: ""
+  working-directory:
+    description: "The directory where composer.json is located, if it is not in the repository root."
+    required: false
 
 runs:
   using: composite
@@ -49,3 +52,4 @@ runs:
         # Revert when psalm supports PHP 8.4
         # composer-options: "--no-suggest"
         composer-options: "--no-suggest ${{ inputs.php-version == '8.4' && '--ignore-platform-req=php+' || '' }}"
+        working-directory: "${{ inputs.working-directory }}"

.github/workflows/generator.yml

@@ -0,0 +1,42 @@
+name: "Generator"
+
+on:
+  merge_group:
+  pull_request:
+    branches:
+      - "v*.*"
+      - "master"
+      - "feature/*"
+  push:
+    branches:
+      - "v*.*"
+      - "master"
+      - "feature/*"
+
+env:
+  PHP_VERSION: "8.2"
+  # TODO: change to "stable" once 1.20.0 is released
+  # DRIVER_VERSION: "stable"
+  DRIVER_VERSION: "mongodb/mongo-php-driver@v1.20"
+
+jobs:
+  psalm:
+    name: "Diff check"
+    runs-on: "ubuntu-22.04"
+
+    steps:
+      - name: "Checkout"
+        uses: "actions/checkout@v4"
+
+      - name: "Setup"
+        uses: "./.github/actions/setup"
+        with:
+          php-version: ${{ env.PHP_VERSION }}
+          driver-version: ${{ env.DRIVER_VERSION }}
+          working-directory: "generator"
+
+      - name: "Run Generator"
+        run: "generator/generate"
+
+      - name: "Check file diff"
+        run: git add . -N && git diff --exit-code