Add watcher that will run tests and lint

README.md

@@ -1237,6 +1237,18 @@ More information about writing rule tests can be found in [TSLint documentation]
 
 Please also see our [Code of Conduct](CODE_OF_CONDUCT.md).
 
+### Watchers
+
+Two npm scripts can be used to watch files and simplify testing and linting with constant changes.
+
+Use `npm start` to start watcher that will rebuild rules and Mocha tests.
+
+> NOTE: Run `npm test` before `npm start` to copy all required files to `dist` folder.
+
+Use `npm run watch:run-tests` that will re-run tests (both Mocha and TSLint) and lint code when: files changed in `tests`, `test-data` or `npm start` compiled rules or tests code.
+
+> NOTE: It is recommended to wait when `npm start` will finish initial compilation before starting `npm run watch:run-tests` (in separate terminal).
+
 ### Debug code
 
 **VS Code**
@@ -1268,8 +1280,6 @@ Set a breakpoint somewhere in your code and resume execution. Your breakpoint sh
 
 You can use `npm start` watcher that will rebuild TS files from `src` before launching debug commands.
 
-> NOTE: Run `npm test` before `npm start` to copy all required files to `dist` folder.
-
 > NOTE: If breakpoints are not hit you can try to use `inlineSourceMaps` instead of `sourceMaps` in `tsconfig.json`
 
 ### Creating a new Release

build-tasks/validate-config.js

@@ -13,25 +13,25 @@ function ruleIsEnabled(value) {
         return false;
     }
 
-    if (typeof value === "boolean") {
+    if (typeof value === 'boolean') {
         return value;
     }
 
     return value[0];
 }
 
 const disabledRules = new Set([
-    "missing-jsdoc",
-    "no-duplicate-case",
-    "no-empty-interfaces",
-    "no-empty-line-after-opening-brace",
-    "no-multiline-string",
-    "no-relative-imports",
-    "no-stateless-class",
-    "no-unexternalized-strings",
-    "no-var-self",
-    "react-tsx-curly-spacing",
-    "valid-typeof",
+    'missing-jsdoc',
+    'no-duplicate-case',
+    'no-empty-interfaces',
+    'no-empty-line-after-opening-brace',
+    'no-multiline-string',
+    'no-relative-imports',
+    'no-stateless-class',
+    'no-unexternalized-strings',
+    'no-var-self',
+    'react-tsx-curly-spacing',
+    'valid-typeof'
 ]);
 
 const errors = [];

build-tasks/watch-run-tests.js

@@ -0,0 +1,72 @@
+const { yellowBright, red, green } = require('chalk');
+const chokidar = require('chokidar');
+const runAll = require('npm-run-all');
+
+const changes = new Set();
+let testsRunning = false;
+
+function simpleDebounce(delay, fn) {
+    let timer;
+
+    return () => {
+        clearTimeout(timer);
+        timer = setTimeout(fn, delay);
+    };
+}
+
+function runTests() {
+    console.log(green('\nStarting tests'));
+
+    testsRunning = true;
+
+    return runAll(['test:*', 'lint:*'], {
+        stdin: process.stdin,
+        stdout: process.stdout,
+        stderr: process.stderr
+    })
+        .then(() => console.log(green('\nSuccess.')))
+        .catch(() => console.error(red('\nFailure!')))
+        .then(() => { testsRunning = false; })
+}
+
+const scheduleTests = simpleDebounce(1000, () => {
+    console.log(yellowBright('Scheduling new tests because of changes in: \n') + [...changes].join('\n'));
+
+    changes.clear();
+
+    runTests()
+        .then(() => {
+            if (changes.size > 0) {
+                scheduleTests();
+            }
+        });
+});
+
+function registerChange(path) {
+    console.log(yellowBright('Registered change: ') + path);
+    changes.add(path);
+
+    if (!testsRunning) {
+        scheduleTests();
+    }
+}
+
+const fileWatcher = chokidar
+    .watch(['dist/src/**/*.js', 'test-data/**', 'tests/**']);
+
+function subscribeFileEvents() {
+    fileWatcher
+        .on('add', registerChange)
+        .on('change', registerChange)
+        .on('unlink', registerChange);
+}
+
+fileWatcher.on('ready', () => {
+    const watchedCount = Object.keys(fileWatcher.getWatched())
+        .reduce((memo, items) => memo + items.length, 0);
+    console.log(`Watching ${watchedCount} files and folders.`);
+
+    subscribeFileEvents();
+
+    runTests();
+});