Add code coverage for unit tests running in node

It's a first step to add code coverage.
In order to get the code coverage report locally, you can run the following command:
```bash
npx gulp unittestcli --coverage
```
The code coverage report will be generated in the `./build/coverage` directory.
And the report can be consulted by opening:
  http://localhost:8888/build/coverage/index.html

A GitHub workflow has also been added to run the unit tests with code coverage
on each push and pull request. The report will be uploaded to Codecov.

Author: calixteman

.c8rc.json

@@ -0,0 +1,13 @@
+{
+  "reporter": ["text", "html", "lcov"],
+  "include": [
+    "build/lib-legacy/core/**/*.js",
+    "build/lib-legacy/display/**/*.js",
+    "build/lib-legacy/shared/**/*.js"
+  ],
+  "exclude": ["build/lib-legacy/test/**"],
+  "all": false,
+  "check-coverage": false,
+  "report-dir": "./build/coverage",
+  "temp-directory": "./build/.c8_output"
+}

.github/workflows/coverage.yml

@@ -0,0 +1,41 @@
+name: Code Coverage
+on: [push, pull_request]
+permissions:
+  contents: read
+
+jobs:
+  test:
+    name: Test
+    runs-on: ubuntu-latest
+
+    strategy:
+      fail-fast: false
+      matrix:
+        node-version: [lts/*]
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
+
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v6
+        with:
+          node-version: ${{ matrix.node-version }}
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Run CLI unit tests with code coverage
+        run: npx gulp unittestcli --coverage
+
+      - name: Upload results to Codecov
+        uses: codecov/codecov-action@v5
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          fail_ci_if_error: true
+          files: ./build/coverage/lcov.info
+          flags: unittestcli
+          name: codecov-umbrella
+          verbose: true

gulpfile.mjs

@@ -1938,16 +1938,40 @@ gulp.task(
     "generic-legacy",
     "lib-legacy",
     function runUnitTestCli(done) {
-      const options = [
-        "node_modules/jasmine/bin/jasmine",
-        "JASMINE_CONFIG_PATH=test/unit/clitests.json",
-      ];
-      const jasmineProcess = startNode(options, { stdio: "inherit" });
+      const useCoverage = process.argv.includes("--coverage");
+
+      if (useCoverage) {
+        console.log("\n### Running unit tests with code coverage");
+      }
+
+      let jasmineProcess;
+      if (useCoverage) {
+        const options = [
+          "node_modules/c8/bin/c8.js",
+          "node",
+          "--max-http-header-size=80000",
+          "node_modules/jasmine/bin/jasmine",
+          "JASMINE_CONFIG_PATH=test/unit/clitests.json",
+        ];
+        jasmineProcess = spawn("node", options, { stdio: "inherit" });
+      } else {
+        const options = [
+          "node_modules/jasmine/bin/jasmine",
+          "JASMINE_CONFIG_PATH=test/unit/clitests.json",
+        ];
+        jasmineProcess = startNode(options, { stdio: "inherit" });
+      }
+
       jasmineProcess.on("close", function (code) {
         if (code !== 0) {
           done(new Error("Unit tests failed."));
           return;
         }
+        if (useCoverage) {
+          console.log(
+            "\n### Code coverage report generated in ./build/coverage directory"
+          );
+        }
         done();
       });
     }