Create rule S5973: Tests should be stable

its/ruling/src/test/expected/jsts/file-for-rules/typescript-S5973.json

@@ -0,0 +1,5 @@
+{
+"file-for-rules:tests/S5973.ts": [
+3
+]
+}

its/sources/jsts/custom/tests/S5973.ts

@@ -0,0 +1,3 @@
+import * as jest from 'jest';
+
+jest.retryTimes(3); // Noncompliant

packages/jsts/src/rules/S5973/fixtures/with-jest/cb.fixture.ts

@@ -0,0 +1,3 @@
+jest.retryTimes(3); // Noncompliant
+
+foo(); // for coverage

packages/jsts/src/rules/S5973/fixtures/with-jest/cb.test.ts

@@ -0,0 +1,36 @@
+/*
+ * SonarQube JavaScript Plugin
+ * Copyright (C) 2011-2023 SonarSource SA
+ * mailto:info AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+import path from 'path';
+import { getAllPackageJsons, searchPackageJsonFiles } from '../../../../';
+import { check } from '../../../tools';
+import { rule } from '../../';
+
+
+const sonarId = path.basename(__dirname);
+
+describe('Rule S5973', () => {
+  beforeEach(() => {
+    searchPackageJsonFiles(__dirname, []);
+  });
+  afterAll(() => {
+    getAllPackageJsons().clear();
+  });
+  check(sonarId, rule, __dirname);
+});

packages/jsts/src/rules/S5973/fixtures/with-jest/package.json

@@ -0,0 +1,15 @@
+{
+  "name": "jest-global",
+  "version": "1.0.0",
+  "description": "",
+  "main": "index.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC",
+  "devDependencies": {
+    "jest": "29.7.0"
+  }
+}

packages/jsts/src/rules/S5973/fixtures/without-jest/cb.test.ts

@@ -0,0 +1,36 @@
+/*
+ * SonarQube JavaScript Plugin
+ * Copyright (C) 2011-2023 SonarSource SA
+ * mailto:info AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+import path from 'path';
+import { getAllPackageJsons, searchPackageJsonFiles } from '../../../../';
+import { check } from '../../../tools';
+import { rule } from '../../';
+
+
+const sonarId = path.basename(__dirname);
+
+describe('Rule S5973', () => {
+  beforeEach(() => {
+    searchPackageJsonFiles(__dirname, []);
+  });
+  afterAll(() => {
+    getAllPackageJsons().clear();
+  });
+  check(sonarId, rule, __dirname);
+});

packages/jsts/src/rules/S5973/fixtures/without-jest/jest-import.fixture.ts

@@ -0,0 +1,3 @@
+import * as jest from 'jest';
+
+jest.retryTimes(3); // Noncompliant

packages/jsts/src/rules/S5973/fixtures/without-jest/mocha.fixture.ts

@@ -0,0 +1,10 @@
+describe('api.foo()', function () {
+  this.retries(2); // Noncompliant
+
+  it('should return 42', function () {
+    this.retries(5); // Noncompliant
+  });
+  it('should return 42', () => {
+    this.retries(5); // Noncompliant - FP, because Mocha callbacks with arrow functions lose context. But we accept this.
+  });
+});

packages/jsts/src/rules/S5973/fixtures/without-jest/package.json

@@ -0,0 +1,12 @@
+{
+  "name": "without-jest",
+  "version": "1.0.0",
+  "description": "",
+  "main": "index.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC"
+}

packages/jsts/src/rules/S5973/index.ts

@@ -0,0 +1,20 @@
+/*
+ * SonarQube JavaScript Plugin
+ * Copyright (C) 2011-2023 SonarSource SA
+ * mailto:info AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+export { rule } from './rule';

packages/jsts/src/rules/S5973/rule.ts

@@ -0,0 +1,101 @@
+/*
+ * SonarQube JavaScript Plugin
+ * Copyright (C) 2011-2023 SonarSource SA
+ * mailto:info AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+// https://sonarsource.github.io/rspec/#/rspec/S5973/javascript
+
+import { Rule } from 'eslint';
+import { Mocha, getFullyQualifiedName, isIdentifier, isMethodInvocation } from '../helpers';
+import * as estree from 'estree';
+import { getDependencies } from '@sonar/jsts';
+
+export const rule: Rule.RuleModule = {
+  meta: {
+    messages: {
+      stable:
+        'Make your tests stable so that they pass on the first try, or remove the flaky ones.',
+    },
+  },
+  create(context: Rule.RuleContext) {
+    const describes: estree.Node[] = [];
+
+    const hasJest = hasJestDependency(context);
+
+    return {
+      /**
+       * We use the stack approach to check for Mocha retries inside describe blocks,
+       * and implicitly test cases.
+       */
+      CallExpression(node: estree.CallExpression) {
+        if (hasJestRetry(context, node, hasJest)) {
+          report(context, node);
+          return;
+        }
+        if (Mocha.isDescribeCase(node)) {
+          describes.push(node);
+          return;
+        }
+        if (describes.length > 0) {
+          checkMochaRetries(context, node);
+        }
+      },
+      'CallExpression:exit': (node: estree.Node) => {
+        if (Mocha.isDescribeCase(node)) {
+          describes.pop();
+        }
+      },
+      'Program:exit': () => {
+        describes.length = 0;
+      },
+    };
+  },
+};
+
+function hasJestRetry(context: Rule.RuleContext, node: estree.CallExpression, hasJest: boolean) {
+  const callExpressionName = getFullyQualifiedName(context, node);
+  return (
+    callExpressionName === 'jest.retryTimes' ||
+    (hasJest && isMethodInvocation(node, 'jest', 'retryTimes', 1))
+  );
+}
+
+function hasJestDependency(context: Rule.RuleContext) {
+  const dependencies = getDependencies(context.filename);
+  return dependencies.has('jest');
+}
+
+/**
+ * Flag if `this.retries()`
+ */
+function checkMochaRetries(context: Rule.RuleContext, node: estree.CallExpression) {
+  const callee = node.callee;
+  if (
+    callee.type === 'MemberExpression' &&
+    callee.object.type === 'ThisExpression' &&
+    isIdentifier(callee.property, 'retries')
+  ) {
+    report(context, node);
+  }
+}
+
+function report(context: Rule.RuleContext, node: estree.CallExpression) {
+  context.report({
+    messageId: 'stable',
+    node,
+  });
+}

packages/jsts/src/rules/helpers/mocha.ts

@@ -63,7 +63,23 @@ export namespace Mocha {
     return null;
   }
 
+  /**
+   * returns true if the node is a test case
+   *
+   * @param node
+   * @returns
+   */
   export function isTestCase(node: estree.Node): boolean {
     return isTestConstruct(node, ['it', 'specify']);
   }
+
+  /**
+   * returns true if the node is a describe block
+   *
+   * @param node
+   * @returns
+   */
+  export function isDescribeCase(node: estree.Node): boolean {
+    return isTestConstruct(node, ['describe']);
+  }
 }

packages/jsts/src/rules/index.ts

@@ -272,6 +272,7 @@ import { rule as S6582 } from './S6582'; // sonar-prefer-optional-chain
 import { rule as S6759 } from './S6759'; // sonar-prefer-read-only-props
 import { rule as S6594 } from './S6594'; // sonar-prefer-regexp-exec
 import { rule as S2077 } from './S2077'; // sql-queries
+import { rule as S5973 } from './S5973'; // stable-tests
 import { rule as S4829 } from './S4829'; // standard-input
 import { rule as S6351 } from './S6351'; // stateful-regex
 import { rule as S5739 } from './S5739'; // strict-transport-security
@@ -559,6 +560,7 @@ rules['sonar-prefer-optional-chain'] = S6582;
 rules['sonar-prefer-read-only-props'] = S6759;
 rules['sonar-prefer-regexp-exec'] = S6594;
 rules['sql-queries'] = S2077;
+rules['stable-tests'] = S5973;
 rules['standard-input'] = S4829;
 rules['stateful-regex'] = S6351;
 rules['strict-transport-security'] = S5739;

sonar-plugin/javascript-checks/src/main/java/org/sonar/javascript/checks/CheckList.java

@@ -421,6 +421,7 @@ public static List<Class<? extends JavaScriptCheck>> getAllChecks() {
       SonarNoMisleadingCharacterClassCheck.class,
       SonarPreferOptionalChainCheck.class,
       SqlQueriesCheck.class,
+      StableTestsCheck.class,
       StandardInputCheck.class,
       StatefulRegexCheck.class,
       StrictModeCheck.class,

sonar-plugin/javascript-checks/src/main/java/org/sonar/javascript/checks/StableTestsCheck.java

@@ -0,0 +1,36 @@
+/**
+ * SonarQube JavaScript Plugin
+ * Copyright (C) 2011-2023 SonarSource SA
+ * mailto:info AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+package org.sonar.javascript.checks;
+
+import org.sonar.check.Rule;
+import org.sonar.plugins.javascript.api.JavaScriptRule;
+import org.sonar.plugins.javascript.api.TestFileCheck;
+import org.sonar.plugins.javascript.api.TypeScriptRule;
+
+@TypeScriptRule
+@JavaScriptRule
+@Rule(key = "S5973")
+public class StableTestsCheck extends TestFileCheck {
+
+  @Override
+  public String eslintKey() {
+    return "stable-tests";
+  }
+}

sonar-plugin/javascript-checks/src/main/resources/org/sonar/l10n/javascript/rules/javascript/S5973.html

@@ -0,0 +1,34 @@
+<h2>Why is this an issue?</h2>
+<p>Unstable / flaky tests are tests which sometimes pass and sometimes fail, without any code change. Obviously, they slow down developments when
+developers have to rerun failed tests. However, the real problem is that you can’t completely trust these tests, they might fail for many different
+reasons and you don’t know if any of them will happen in production.</p>
+<p>Some tools, such as Jest, enable developers to automatically retry flaky tests. This might be acceptable as a temporary solution, but it should
+eventually be fixed. The more flaky tests you add, the more chances there are for a bug to arrive in production.</p>
+<p>This rule raises an issue when these functions are called with a value higher than <code>0</code>: * <code>jest.retry()</code> *
+<code>this.retries()</code> inside a Mocha test case</p>
+<h2>How to fix it</h2>
+<p>Make your test stable so that it passes on the first try, or remove it.</p>
+<h3>Code examples</h3>
+<h4>Noncompliant code example</h4>
+<pre>
+jest.retryTimes(3); // Noncompliant
+
+describe('API.foo()', function() {
+  it('should return 5 when computing ...', function() {
+    doSomethingUnstable();
+  });
+});
+</pre>
+<h2>Resources</h2>
+<h3>Documentation</h3>
+<ul>
+  <li> Jest docs - <a href="https://jestjs.io/docs/jest-object#jestretrytimesnumretries-options">jest.retryTimes()</a> </li>
+  <li> Mocha docs - <a href="https://mochajs.org/#retry-tests">Retry tests</a> </li>
+</ul>
+<h3>Articles &amp; blog posts</h3>
+<ul>
+  <li> Spotify Engineering - <a
+  href="https://engineering.atspotify.com/2019/11/18/test-flakiness-methods-for-identifying-and-dealing-with-flaky-tests/">Test Flakiness - Methods
+  for identifying and dealing with flaky tests</a> </li>
+</ul>
+