Add a missing tests check and update CONTRIBUTING.md (#308)

.github/workflows/tests_check.yml

@@ -0,0 +1,37 @@
+name: Check for Tests in PR
+
+on:
+  pull_request:
+    types: [opened, synchronize, reopened]
+
+jobs:
+  check-for-tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+
+      - name: Check for changes in test directory
+        id: check-tests
+        run: |
+          git status --porcelain > changed_files.txt
+          if grep -qE "^[AM]\s+test/" changed_files.txt; then
+            echo "Tests found in the PR"
+            echo "tests_present=true" >> $GITHUB_OUTPUT
+          else
+            echo "No tests found in the PR"
+            echo "tests_present=false" >> $GITHUB_OUTPUT
+          fi
+
+      - name: Comment on PR if tests are missing
+        if: steps.check-tests.outputs.tests_present == 'false'
+        uses: actions/[email protected]
+        with:
+          script: |
+            github.rest.issues.createComment({
+              issue_number: context.issue.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              body: 'It appears that this PR does not include any tests. It is recommended to add tests, especially for critical changes, to ensure code quality and prevent regressions. However, if this PR is only updating samples or documentation, feel free to skip adding tests and disregard this comment.'
+            })

CONTRIBUTING.md

@@ -22,4 +22,9 @@ To get started with contributing, please follow the steps below:
    ```bash
    melos analyze
    ```
-9. Create a pull request.
+9. Make sure all existing tests pass and add new tests for the changes you made.
+   Execute the following command to run the tests.
+   ```bash
+   melos test
+   ```
+10. Create a pull request.

melos.yaml

@@ -23,3 +23,5 @@ scripts:
     exec: dart analyze .
   format:
     exec: dart format --set-exit-if-changed .
+  test:
+    exec: flutter test