Add subsetting to Karma runner

Author: gayanW

launchable/commands/subset.py

@@ -529,7 +529,7 @@ def get_payload(
 
         def _collect_potential_test_files(self):
             LOOSE_TEST_FILE_PATTERN = r'(\.(test|spec)\.|_test\.|Test\.|Spec\.|test/|tests/|__tests__/|src/test/)'
-            EXCLUDE_PATTERN = r'(BUILD|Makefile|Dockerfile|LICENSE|.gitignore|.gitkeep|.keep|id_rsa|rsa|blank|taglib)|\.(xml|json|jsonl|txt|yml|yaml|toml|md|png|jpg|jpeg|gif|svg|sql|html|css|graphql|proto|gz|zip|rz|bzl|conf|config|snap|pem|crt|key|lock|jpi|hpi|jelly|properties|jar|ini|mod|sum|bmp|env|envrc|sh)$' ## noqa E501
+            EXCLUDE_PATTERN = r'(BUILD|Makefile|Dockerfile|LICENSE|.gitignore|.gitkeep|.keep|id_rsa|rsa|blank|taglib)|\.(xml|json|jsonl|txt|yml|yaml|toml|md|png|jpg|jpeg|gif|svg|sql|html|css|graphql|proto|gz|zip|rz|bzl|conf|config|snap|pem|crt|key|lock|jpi|hpi|jelly|properties|jar|ini|mod|sum|bmp|env|envrc|sh)$'  # noqa E501
 
             try:
                 git_managed_files = subprocess.run(['git', 'ls-files'], stdout=subprocess.PIPE,

launchable/test_runners/karma.py

@@ -1,6 +1,3 @@
-# This runner only supports recording tests
-# For subsetting, use 'ng' test runner instead
-# It's possible to use 'karma' runner for recording, and 'ng' runner for subsetting, for the same test session
 import json
 from typing import Dict, Generator, List
 
@@ -34,6 +31,30 @@ def record_tests(client, reports):
     client.run()
 
 
+@click.option('--with', 'output_format', type=str, default=None,
+              help='Format output for specific test runner (e.g., "ng" for Angular CLI)')
+@launchable.subset
+def subset(client, output_format):
+    """
+    Usage:
+        find src -name "*.spec.ts" -o -name "*.spec.js" > test-list.txt
+        cat test-list.txt | launchable subset --target 10% karma
+
+        # Output in ng test format
+        find src -name "*.spec.ts" | launchable subset --target 10% karma --with ng
+    """
+    for t in client.stdin():
+        path = t.strip()
+        if path:
+            client.test_path(path)
+
+    if output_format == 'ng':
+        client.formatter = lambda x: "--include={}".format(x[0]['name'])
+        client.separator = " "
+
+    client.run()
+
+
 class JSONReportParser:
     """
     Sample Karma report format:

tests/data/karma/README.md

@@ -0,0 +1,155 @@
+Karma
+======
+
+### Karma Project
+
+**Create project:**
+
+```bash
+npm init -y
+npm install --save-dev karma karma-jasmine jasmine-core karma-chrome-launcher karma-json-reporter
+```
+The instructions are based on:
+https://karma-runner.github.io/6.4/intro/installation.html
+
+**Generate `karma.conf.js`:**
+```bash
+npx karma init
+
+# Answer the prompts:
+# - Framework: jasmine
+# - Require.js: no
+# - Browser: ChromeHeadless
+# - Test files: 
+# - Files to exclude:
+# - Watch files: no
+```
+
+**Add following to `karma.conf.js` while keeping the current settings:**
+```
+module.exports = function (config) {
+  config.set({
+    files: process.env.KARMA_FILES ? JSON.parse(process.env.KARMA_FILES) : [],
+    ...
+    plugins: [
+      ...
+      require('karma-json-reporter')
+    ],
+    jsonReporter: {
+      outputFile: require('path').join(__dirname, 'test-results.json'),
+      stdout: false
+    },
+    reporters: [..., 'json']
+  });
+};
+```
+
+**Create a test file:**
+```bash
+mkdir test
+
+cat > test/example.spec.js << 'EOF'
+describe('Example', function() {
+  it('should pass', function() {
+    expect(true).toBe(true);
+  });
+
+  it('should add numbers', function() {
+    expect(1 + 1).toBe(2);
+  });
+});
+EOF
+```
+
+**Record session:**
+```bash
+git add . && git commit -m "Initial commit"
+launchable record build --name ${BUILD_NAME}
+launchable record session --build ${BUILD_NAME} > session.txt
+```
+
+**Run all tests:**
+```bash
+find test -name "*.spec.ts" -o -name "*.spec.js" > test_list.txt
+cat test_list.txt
+KARMA_FILES=$(cat test_list.txt | jq -R -s -c 'split("\n")[:-1]')
+npx karma start --single-run
+```
+
+**Record tests:**
+```bash
+launchable record tests karma test-results.json
+```
+
+**Request subset:**
+```bash
+cat test_list.txt | launchable subset --target 25% karma  > subset.txt
+```
+
+**Run subset of tests:**
+```bash
+KARMA_FILES=$(cat subset.txt | jq -R -s -c 'split("\n")[:-1]')
+npx karma start --single-run
+```
+
+### Angular Project with Karma
+
+**Create project:**
+
+```
+ng new ng-karma-app --test-runner=karma
+cd ng-karma-app
+npm install --save-dev karma karma-chrome-launcher karma-coverage karma-jasmine karma-jasmine-html-reporter jasmine-core karma-json-reporter @types/jasmine
+ng test --no-watch --no-progress --browsers=ChromeHeadless
+```
+
+The instructions are based on:
+- https://angular.dev/guide/testing/karma
+- https://www.npmjs.com/package/karma-json-reporter
+
+**Generate `karma.conf.js`:**
+```
+ng generate config karma
+```
+
+**Add following to `karma.conf.js` while keeping the current settings:**
+```
+module.exports = function (config) {
+  config.set({
+    ...
+    plugins: [
+      ...
+      require('karma-json-reporter')
+    ],
+    jsonReporter: {
+      outputFile: require('path').join(__dirname, 'test-results.json'),
+      stdout: false
+    },
+    reporters: [..., 'json']
+  });
+};
+```
+
+**Record session:**
+```
+git add . && git commit -m "Initial commit"
+launchable record build --name ${BUILD_NAME}
+launchable record session --build ${BUILD_NAME} > session.txt
+```
+
+**Record tests:**
+```
+ng test --no-watch --no-progress --browsers=ChromeHeadless
+launchable record tests karma test-results.json
+```
+
+**Subset tests with **ng**:**
+```
+ng test --list-tests | grep src > test_list.txt
+cat test_list.txt | launchable subset --target 25% karma --with ng > subset.txt
+```
+
+**Run subset of tests**
+```
+ng test --no-watch --no-progress --browsers=ChromeHeadless --include $(cat subset.txt)
+```

tests/data/ng/subset_payload.json tests/data/karma/subset_payload.jsontests/data/ng/subset_payload.json renamed to tests/data/karma/subset_payload.json

@@ -4,13 +4,13 @@
       { "type": "file", "name": "foo/bar/zot.spec.ts" }
     ],
     [
-      { "type": "file", "name": "client-source/src/app/shared/other-test.spec.ts" }
+      { "type": "file", "name": "foo/bar/another.spec.ts" }
     ]
   ],
-  "testRunner": "ng",
+  "testRunner": "karma",
   "goal": {"type": "subset-by-percentage", "percentage": 0.1},
   "ignoreNewTests": false,
   "session": { "id": "16" },
   "getTestsFromGuess": false,
   "getTestsFromPreviousSessions": false
-}
+}

tests/test_runners/test_karma.py

@@ -19,12 +19,27 @@ def test_record_tests_json(self):
         self.assert_record_tests_payload('record_test_result.json')
 
     @responses.activate
-    @mock.patch.dict(os.environ, {"LAUNCHABLE_TOKEN": CliTestCase.launchable_token})
+    @mock.patch.dict(os.environ,
+                     {"LAUNCHABLE_TOKEN": CliTestCase.launchable_token})
     def test_subset(self):
-        # emulate launchable record build
         write_build(self.build_name)
 
-        result = self.cli('subset', '--target', '10%', '--base',
-                          os.getcwd(), 'karma', '--with', 'ng', input="a.ts\nb.ts")
+        subset_input = """foo/bar/zot.spec.ts
+foo/bar/another.spec.ts
+"""
+        result = self.cli('subset', '--target', '10%', 'karma', input=subset_input)
+        self.assert_success(result)
+        self.assert_subset_payload('subset_payload.json')
+
+    @responses.activate
+    @mock.patch.dict(os.environ,
+                     {"LAUNCHABLE_TOKEN": CliTestCase.launchable_token})
+    def test_subset_with_ng(self):
+        write_build(self.build_name)
+
+        subset_input = """foo/bar/zot.spec.ts
+foo/bar/another.spec.ts
+"""
+        result = self.cli('subset', '--target', '10%', 'karma', '--with', 'ng', input=subset_input)
         self.assert_success(result)
-        self.assert_subset_payload('subset_result.json')
+        self.assert_subset_payload('subset_payload.json')