diff --git a/CHANGELOG.md b/CHANGELOG.md index a07647c82d..9bc4a25beb 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -8,6 +8,7 @@ This change log adheres to standards from [Keep a CHANGELOG](https://keepachange ### Added - [`dynamic-import-chunkname`]: add `allowEmpty` option to allow empty leading comments ([#2942], thanks [@JiangWeixian]) +- [`no-rename-default`]: Forbid importing a default export by a different name ([#3006], thanks [@whitneyit]) ### Changed - [Docs] `no-extraneous-dependencies`: Make glob pattern description more explicit ([#2944], thanks [@mulztob]) diff --git a/README.md b/README.md index d6f107d1c9..925e86ee47 100644 --- a/README.md +++ b/README.md @@ -37,6 +37,7 @@ This plugin intends to support linting of ES2015+ (ES6+) import/export syntax, a | [no-mutable-exports](docs/rules/no-mutable-exports.md) | Forbid the use of mutable exports with `var` or `let`. | | | | | | | | [no-named-as-default](docs/rules/no-named-as-default.md) | Forbid use of exported name as identifier of default export. | | ☑️ 🚸 | | | | | | [no-named-as-default-member](docs/rules/no-named-as-default-member.md) | Forbid use of exported name as property of default export. | | ☑️ 🚸 | | | | | +| [no-rename-default](docs/rules/no-rename-default.md) | Forbid importing a default export by a different name. | | 🚸 | | | | | | [no-unused-modules](docs/rules/no-unused-modules.md) | Forbid modules without exports, or exports without matching import in another module. | | | | | | | ### Module systems diff --git a/config/warnings.js b/config/warnings.js index 5d74143b28..499f3193b2 100644 --- a/config/warnings.js +++ b/config/warnings.js @@ -7,6 +7,7 @@ module.exports = { rules: { 'import/no-named-as-default': 1, 'import/no-named-as-default-member': 1, + 'import/no-rename-default': 1, 'import/no-duplicates': 1, }, }; diff --git a/docs/rules/no-rename-default.md b/docs/rules/no-rename-default.md new file mode 100644 index 0000000000..ec53a6a0ba --- /dev/null +++ b/docs/rules/no-rename-default.md @@ -0,0 +1,31 @@ +# import/no-rename-default + +⚠️ This rule _warns_ in the 🚸 `warnings` config. + + + +Prohibit importing a default export by another name. + +## Rule Details + +Given: + +```js +// api/get-users.js +export default async function getUsers() {} +``` + +...this would be valid: + +```js +import getUsers from './api/get-users.js'; +``` + +...and the following would be reported: + +```js +// Caution: `get-users.js` has a default export `getUsers`. +// This imports `getUsers` as `findUsers`. +// Check if you meant to write `import getUsers from './api/get-users'` instead. +import findUsers from './get-users'; +``` diff --git a/src/index.js b/src/index.js index feafba9003..c32f7ba907 100644 --- a/src/index.js +++ b/src/index.js @@ -20,6 +20,7 @@ export const rules = { 'no-named-as-default': require('./rules/no-named-as-default'), 'no-named-as-default-member': require('./rules/no-named-as-default-member'), 'no-anonymous-default-export': require('./rules/no-anonymous-default-export'), + 'no-rename-default': require('./rules/no-rename-default'), 'no-unused-modules': require('./rules/no-unused-modules'), 'no-commonjs': require('./rules/no-commonjs'), diff --git a/src/rules/no-rename-default.js b/src/rules/no-rename-default.js new file mode 100644 index 0000000000..b3910a864d --- /dev/null +++ b/src/rules/no-rename-default.js @@ -0,0 +1,157 @@ +/** + * @fileOverview Rule to warn about importing a default export by different name + * @author James Whitney + */ + +import docsUrl from '../docsUrl'; +import ExportMapBuilder from '../exportMap/builder'; +import path from 'path'; + +//------------------------------------------------------------------------------ +// Rule Definition +//------------------------------------------------------------------------------ + +/** @type {import('@typescript-eslint/utils').TSESLint.RuleModule} */ +const rule = { + meta: { + type: 'suggestion', + docs: { + category: 'Helpful warnings', + description: 'Forbid importing a default export by a different name.', + recommended: false, + url: docsUrl('no-named-as-default'), + }, + schema: [ + { + type: 'object', + properties: { + commonjs: { + type: 'boolean', + }, + }, + additionalProperties: false, + }, + ], + }, + + create(context) { + function getDefaultExportName(defaultExportNode) { + return defaultExportNode.declaration.name; + } + + function getDefaultExportNode(exportMap) { + const defaultExportNode = exportMap.exports.get('default'); + if (defaultExportNode == null) { + return; + } + return defaultExportNode; + } + + function getExportMap(source, context) { + const exportMap = ExportMapBuilder.get(source.value, context); + if (exportMap == null) { + return; + } + if (exportMap.errors.length > 0) { + exportMap.reportErrors(context, source.value); + return; + } + return exportMap; + } + + return { + ImportDeclaration(node) { + const exportMap = getExportMap(node.source, context); + if (exportMap == null) { + return; + } + + const defaultExportNode = getDefaultExportNode(exportMap); + if (defaultExportNode == null) { + return; + } + + const defaultExportName = getDefaultExportName(defaultExportNode); + const importTarget = node.source.value; + const importBasename = path.basename(exportMap.path); + + node.specifiers.forEach((importClause) => { + const importName = importClause.local.name; + + // No named default export + if (defaultExportName === undefined) { + return; + } + + // The name of the import matches the name of the default export. + if (importName === defaultExportName) { + return; + } + + context.report({ + node: importClause, + message: `Caution: \`${importBasename}\` has a default export \`${defaultExportName}\`. This imports \`${defaultExportName}\` as \`${importName}\`. Check if you meant to write \`import ${defaultExportName} from '${importTarget}'\` instead.`, + }); + }); + }, + VariableDeclarator(node) { + const options = context.options[0] || {}; + + if ( + !options.commonjs + || node.type !== 'VariableDeclarator' + // return if it's not an object destructure or it's an empty object destructure + || !node.id || node.id.type !== 'Identifier' + // return if there is no call expression on the right side + || !node.init || node.init.type !== 'CallExpression' + ) { + return; + } + + const call = node.init; + const [source] = call.arguments; + + if ( + // return if it's not a commonjs require statement + call.callee.type !== 'Identifier' || call.callee.name !== 'require' || call.arguments.length !== 1 + // return if it's not a string source + || source.type !== 'Literal' + ) { + return; + } + + const exportMap = getExportMap(source, context); + if (exportMap == null) { + return; + } + + const defaultExportNode = getDefaultExportNode(exportMap); + if (defaultExportNode == null) { + return; + } + + const defaultExportName = getDefaultExportName(defaultExportNode); + const requireTarget = source.value; + const requireBasename = path.basename(exportMap.path); + const requireName = node.id.name; + + // No named default export + if (defaultExportName === undefined) { + return; + } + + // The name of the require matches the name of the default export. + if (requireName === defaultExportName) { + return; + } + + context.report({ + node, + message: `Caution: \`${requireBasename}\` has a default export \`${defaultExportName}\`. This requires \`${defaultExportName}\` as \`${requireName}\`. Check if you meant to write \`const ${defaultExportName} = require('${requireTarget}')\` instead.`, + }); + }, + }; + }, +}; + +module.exports = rule; diff --git a/tests/files/no-rename-default/anon.js b/tests/files/no-rename-default/anon.js new file mode 100644 index 0000000000..ff8b4c5632 --- /dev/null +++ b/tests/files/no-rename-default/anon.js @@ -0,0 +1 @@ +export default {}; diff --git a/tests/files/no-rename-default/named-bar.js b/tests/files/no-rename-default/named-bar.js new file mode 100644 index 0000000000..3f10552e18 --- /dev/null +++ b/tests/files/no-rename-default/named-bar.js @@ -0,0 +1,3 @@ +const bar = 'bar'; + +export default bar; diff --git a/tests/files/no-rename-default/named-foo.js b/tests/files/no-rename-default/named-foo.js new file mode 100644 index 0000000000..109ee61e04 --- /dev/null +++ b/tests/files/no-rename-default/named-foo.js @@ -0,0 +1,3 @@ +const foo = 'foo'; + +export default foo; diff --git a/tests/files/no-rename-default/primitive.js b/tests/files/no-rename-default/primitive.js new file mode 100644 index 0000000000..05e0871204 --- /dev/null +++ b/tests/files/no-rename-default/primitive.js @@ -0,0 +1 @@ +export default 123; diff --git a/tests/src/rules/no-rename-default.js b/tests/src/rules/no-rename-default.js new file mode 100644 index 0000000000..effbff7f1b --- /dev/null +++ b/tests/src/rules/no-rename-default.js @@ -0,0 +1,94 @@ +import { RuleTester } from 'eslint'; +import { test } from '../utils'; + +const ruleTester = new RuleTester(); +const rule = require('rules/no-rename-default'); + +ruleTester.run('no-rename-default', rule, { + valid: [ + test({ + code: ` + import _ from './no-rename-default/anon.js' + `, + }), + test({ + code: ` + import bar from './no-rename-default/named-bar' + import foo from './no-rename-default/named-foo' + `, + }), + test({ + code: ` + import _ from './no-rename-default/primitive' + `, + }), + test({ + code: ` + const _ = require('./no-rename-default/anon.js') + `, + options: [{ commonjs: true }], + }), + test({ + code: ` + const bar = require('./no-rename-default/named-bar') + const foo = require('./no-rename-default/named-foo') + `, + options: [{ commonjs: true }], + }), + test({ + code: ` + const _ = require('./no-rename-default/primitive') + `, + options: [{ commonjs: true }], + }), + ], + + invalid: [ + test({ + code: ` + import bar from './no-rename-default/named-foo' + `, + errors: [{ + message: 'Caution: `named-foo.js` has a default export `foo`. This imports `foo` as `bar`. Check if you meant to write `import foo from \'./no-rename-default/named-foo\'` instead.', + type: 'ImportDefaultSpecifier', + }], + }), + test({ + code: ` + import foo from './no-rename-default/named-bar' + import bar from './no-rename-default/named-foo' + `, + errors: [{ + message: 'Caution: `named-bar.js` has a default export `bar`. This imports `bar` as `foo`. Check if you meant to write `import bar from \'./no-rename-default/named-bar\'` instead.', + type: 'ImportDefaultSpecifier', + }, { + message: 'Caution: `named-foo.js` has a default export `foo`. This imports `foo` as `bar`. Check if you meant to write `import foo from \'./no-rename-default/named-foo\'` instead.', + type: 'ImportDefaultSpecifier', + }], + }), + test({ + code: ` + const bar = require('./no-rename-default/named-foo') + `, + options: [{ commonjs: true }], + errors: [{ + message: 'Caution: `named-foo.js` has a default export `foo`. This requires `foo` as `bar`. Check if you meant to write `const foo = require(\'./no-rename-default/named-foo\')` instead.', + type: 'VariableDeclarator', + }], + }), + test({ + code: ` + const foo = require('./no-rename-default/named-bar') + const bar = require('./no-rename-default/named-foo') + `, + options: [{ commonjs: true }], + errors: [{ + message: 'Caution: `named-bar.js` has a default export `bar`. This requires `bar` as `foo`. Check if you meant to write `const bar = require(\'./no-rename-default/named-bar\')` instead.', + type: 'VariableDeclarator', + }, { + message: 'Caution: `named-foo.js` has a default export `foo`. This requires `foo` as `bar`. Check if you meant to write `const foo = require(\'./no-rename-default/named-foo\')` instead.', + type: 'VariableDeclarator', + }], + }), + ], +});