chore(no-identical-title): migrate to TS (#348)

src/rules/__tests__/no-identical-title.test.js → src/rules/__tests__/no-identical-title.test.ts

@@ -1,7 +1,11 @@
-import { RuleTester } from 'eslint';
+import { TSESLint } from '@typescript-eslint/experimental-utils';
 import rule from '../no-identical-title';
 
-const ruleTester = new RuleTester();
+const ruleTester = new TSESLint.RuleTester({
+  parserOptions: {
+    ecmaVersion: 6,
+  },
+});
 
 ruleTester.run('no-identical-title', rule, {
   valid: [
@@ -58,21 +62,8 @@ ruleTester.run('no-identical-title', rule, {
       'describe("describe2", function() {});',
     ].join('\n'),
     ['it("it" + n, function() {});', 'it("it" + n, function() {});'].join('\n'),
-    {
-      code: [
-        'it(`it${n}`, function() {});',
-        'it(`it${n}`, function() {});',
-      ].join('\n'),
-      env: {
-        es6: true,
-      },
-    },
-    {
-      code: 'it(`${n}`, function() {});',
-      env: {
-        es6: true,
-      },
-    },
+    ['it(`it${n}`, function() {});', 'it(`it${n}`, function() {});'].join('\n'),
+    'it(`${n}`, function() {});',
     [
       'describe("title " + foo, function() {',
       '    describe("describe1", function() {});',
@@ -87,54 +78,28 @@ ruleTester.run('no-identical-title', rule, {
       '    });',
       '});',
     ].join('\n'),
-    {
-      code: [
-        'describe("describe", () => {',
-        '    it(`testing ${someVar} with the same title`, () => {});',
-        '    it(`testing ${someVar} with the same title`, () => {});',
-        '});',
-      ].join('\n'),
-      env: {
-        es6: true,
-      },
-    },
-    {
-      code: ['it(`it1`, () => {});', 'it(`it2`, () => {});'].join('\n'),
-      env: {
-        es6: true,
-      },
-    },
-    {
-      code: [
-        'describe(`describe1`, () => {});',
-        'describe(`describe2`, () => {});',
-      ].join('\n'),
-      env: {
-        es6: true,
-      },
-    },
-    {
-      code: [
-        'const test = { content: () => "foo" }',
-        'test.content(`testing backticks with the same title`);',
-        'test.content(`testing backticks with the same title`);',
-      ].join('\n'),
-      env: {
-        es6: true,
-      },
-    },
-    {
-      code: [
-        'const describe = { content: () => "foo" }',
-        'describe.content(`testing backticks with the same title`);',
-        'describe.content(`testing backticks with the same title`);',
-      ].join('\n'),
-      env: {
-        es6: true,
-      },
-    },
+    [
+      'describe("describe", () => {',
+      '    it(`testing ${someVar} with the same title`, () => {});',
+      '    it(`testing ${someVar} with the same title`, () => {});',
+      '});',
+    ].join('\n'),
+    ['it(`it1`, () => {});', 'it(`it2`, () => {});'].join('\n'),
+    [
+      'describe(`describe1`, () => {});',
+      'describe(`describe2`, () => {});',
+    ].join('\n'),
+    [
+      'const test = { content: () => "foo" }',
+      'test.content(`testing backticks with the same title`);',
+      'test.content(`testing backticks with the same title`);',
+    ].join('\n'),
+    [
+      'const describe = { content: () => "foo" }',
+      'describe.content(`testing backticks with the same title`);',
+      'describe.content(`testing backticks with the same title`);',
+    ].join('\n'),
   ],
-
   invalid: [
     {
       code: [
@@ -208,9 +173,6 @@ ruleTester.run('no-identical-title', rule, {
         '    it(`testing backticks with the same title`, () => {});',
         '});',
       ].join('\n'),
-      env: {
-        es6: true,
-      },
       errors: [{ messageId: 'multipleTestTitle', column: 5, line: 3 }],
     },
   ],

src/rules/no-identical-title.ts

@@ -0,0 +1,77 @@
+import {
+  createRule,
+  getStringValue,
+  hasExpressions,
+  isDescribe,
+  isStringNode,
+  isTemplateLiteral,
+  isTestCase,
+} from './tsUtils';
+
+interface DescribeContext {
+  describeTitles: string[];
+  testTitles: String[];
+}
+
+const newDescribeContext = (): DescribeContext => ({
+  describeTitles: [],
+  testTitles: [],
+});
+
+export default createRule({
+  name: __filename,
+  meta: {
+    docs: {
+      category: 'Best Practices',
+      description: 'Disallow identical titles',
+      recommended: 'error',
+    },
+    messages: {
+      multipleTestTitle:
+        'Test title is used multiple times in the same describe block.',
+      multipleDescribeTitle:
+        'Describe block title is used multiple times in the same describe block.',
+    },
+    schema: [],
+    type: 'suggestion',
+  },
+  defaultOptions: [],
+  create(context) {
+    const contexts = [newDescribeContext()];
+    return {
+      CallExpression(node) {
+        const currentLayer = contexts[contexts.length - 1];
+        if (isDescribe(node)) {
+          contexts.push(newDescribeContext());
+        }
+        const [firstArgument] = node.arguments;
+        if (
+          !isStringNode(firstArgument) ||
+          (isTemplateLiteral(firstArgument) && hasExpressions(firstArgument))
+        ) {
+          return;
+        }
+        const title = getStringValue(firstArgument);
+        if (isTestCase(node)) {
+          if (currentLayer.testTitles.includes(title)) {
+            context.report({ messageId: 'multipleTestTitle', node });
+          }
+          currentLayer.testTitles.push(title);
+        }
+
+        if (!isDescribe(node)) {
+          return;
+        }
+        if (currentLayer.describeTitles.includes(title)) {
+          context.report({ messageId: 'multipleDescribeTitle', node });
+        }
+        currentLayer.describeTitles.push(title);
+      },
+      'CallExpression:exit'(node) {
+        if (isDescribe(node)) {
+          contexts.pop();
+        }
+      },
+    };
+  },
+});

src/rules/util.js

@@ -97,53 +97,12 @@ export const argument = node =>
 export const argument2 = node =>
   node.parent.parent.parent.arguments && node.parent.parent.parent.arguments[0];
 
-const describeAliases = new Set(['describe', 'fdescribe', 'xdescribe']);
-
-const testCaseNames = new Set(['fit', 'it', 'test', 'xit', 'xtest']);
-
-const describeProperties = new Set(['each', 'only', 'skip']);
-
-const testCaseProperties = new Set(['each', 'only', 'skip', 'todo']);
-
-export const isTestCase = node =>
-  node &&
-  node.type === 'CallExpression' &&
-  ((node.callee.type === 'Identifier' && testCaseNames.has(node.callee.name)) ||
-    (node.callee.type === 'MemberExpression' &&
-      node.callee.object.type === 'Identifier' &&
-      testCaseNames.has(node.callee.object.name) &&
-      node.callee.property.type === 'Identifier' &&
-      testCaseProperties.has(node.callee.property.name)));
-
-export const isDescribe = node =>
-  node &&
-  node.type === 'CallExpression' &&
-  ((node.callee.type === 'Identifier' &&
-    describeAliases.has(node.callee.name)) ||
-    (node.callee.type === 'MemberExpression' &&
-      node.callee.object.type === 'Identifier' &&
-      describeAliases.has(node.callee.object.name) &&
-      node.callee.property.type === 'Identifier' &&
-      describeProperties.has(node.callee.property.name)));
-
 export const isFunction = node =>
   node &&
   (node.type === 'FunctionExpression' ||
     node.type === 'ArrowFunctionExpression');
 
-export const isString = node =>
-  node &&
-  ((node.type === 'Literal' && typeof node.value === 'string') ||
-    isTemplateLiteral(node));
-
-export const isTemplateLiteral = node =>
-  node && node.type === 'TemplateLiteral';
-
-export const hasExpressions = node =>
-  node && node.expressions && node.expressions.length > 0;
-
-export const getStringValue = arg =>
-  isTemplateLiteral(arg) ? arg.quasis[0].value.raw : arg.value;
+export const getStringValue = arg => arg.quasis[0].value.raw;
 
 /**
  * Generates the URL to documentation for the given rule name. It uses the