Introduced a workflow to calculate the test coverage of the codebase …

…and post it as a comment in the PR.

.github/actions/coverage/action.yml

@@ -0,0 +1,12 @@
+---
+name: 'Publish coverage report'
+description: 'Create or update PR comment with coverage report'
+
+inputs:
+  coverage: 
+    description: The coverage report to publish
+    required: true
+
+runs:
+  using: 'node16'
+  main: 'index.js'

.github/actions/coverage/index.js

@@ -0,0 +1,16 @@
+const core = require('@actions/core');
+const fs = require('fs');
+
+const inputs = {
+    coverage: core.getInput('coverage'),
+    target: core.getInput('target'),
+};
+
+
+(async () => {
+    const { updateComment } = require("../../utils/github");
+
+    const data = fs.readFileSync(inputs.coverage, { encoding: 'utf8', flag: 'r' });
+    await updateComment(inputs.target, data);
+})();
+

.github/actions/node-cache/action.yml

@@ -0,0 +1,21 @@
+---
+name: "Cache Node modules"
+description: "Cache Node modules"
+
+runs:
+  using: "composite"
+  steps:
+    - name: Restore node modules from cache
+      id: cache-nodemodules
+      uses: actions/cache/restore@v3
+      with:
+        # cache whole node_modules instead of ./npm, means `npm ci` will be skipped if cache hit, https://www.voorhoede.nl/en/blog/super-fast-npm-install-on-github-actions/
+        path: ./node_modules
+        key: ${{ runner.os }}-nodemodules-${{ hashFiles('yarn.lock') }}
+        restore-keys: |
+          ${{ runner.os }}-nodemodules-
+
+    - name: Install dependencies
+      if: steps.cache-nodemodules.outputs.cache-hit != 'true'
+      shell: bash
+      run: yarn install --ignore-scripts

.github/utils/github.js

@@ -0,0 +1,47 @@
+const { getOctokit, context } = require("@actions/github");
+const { EOL } = require('os');
+const githubToken = process.env.GITHUB_TOKEN;
+const octokit = githubToken && getOctokit(githubToken);
+
+const OWNER = 'immutable';
+const REPO = 'zkevm-bridge-contracts';
+const REPORT_TITLE = `# 📃CI Report${EOL}`;
+const pr = context.payload.number;
+
+const getExistingReportComment = async () => getExistingComment(REPORT_TITLE);
+
+const getExistingComment = async (head) => {
+    const { data: comments } = await octokit.rest.issues.listComments({
+        owner: OWNER,
+        repo: REPO,
+        issue_number: pr,
+    });
+    return comments.find(comment => comment.body.includes(head));
+}
+
+const createComment = (report) => {
+    return octokit.rest.issues.createComment({
+        owner: OWNER,
+        repo: REPO,
+        issue_number: pr,
+        body: report
+    });
+}
+
+const updateComment = (id, report) => {
+    return octokit.rest.issues.updateComment({
+        owner: OWNER,
+        repo: REPO,
+        comment_id: id,
+        body: report
+    });
+}
+
+exports.updateComment = async (target, report) => {
+    const comment = await getExistingReportComment();
+    if (comment) {
+        await updateComment(comment.id, REPORT_TITLE + report);
+    } else {
+        await createComment(REPORT_TITLE + report);
+    }
+}

.github/workflows/coverage.yml

@@ -0,0 +1,50 @@
+name: Coverage Report
+
+on:
+    pull_request:
+
+env:
+  FOUNDRY_PROFILE: ci
+  GITHUB_TOKEN: ${{ secrets.PLATFORM_SA_GITHUB_TOKEN }}
+
+jobs:
+  check:
+    strategy:
+      fail-fast: true
+
+    name: Foundry project
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          submodules: recursive
+
+      - name: Restore node modules from cache
+        uses: ./.github/actions/node-cache
+
+      - name: Install Foundry
+        uses: foundry-rs/foundry-toolchain@v1
+        with:
+          version: nightly
+
+      - name: Run Forge build
+        run: |
+          forge --version
+          forge build --sizes
+        id: build
+
+      - name: Run Forge coverage
+        run: |
+          forge coverage --report summary > ./coverage.out
+        id: coverage
+
+      - name: Debug coverage report
+        run: |
+          cat ./coverage.out
+
+      - name: Publish report
+        uses: ./.github/actions/coverage
+        with:
+          coverage: ./coverage.out
+          target: coverage
+

.gitignore

@@ -30,3 +30,6 @@ broadcast/DeployRootContracts.s.sol/2500/
 broadcast/DeployChildContracts.s.sol/2501/
 
 node_modules/
+
+# MacOS
+.DS_Store