Add no-import-test-file rule (#193)

Fixes #141

Author: Henri

docs/rules/no-import-test-files.md

@@ -0,0 +1,68 @@
+# Ensure no test files are imported anywhere
+
+This rule will verify that you don't import any test files. It will consider the root of the project to be the closest folder containing a `package.json` file, and will not do anything if it can't find one. Test files in `node_modules` will not be linted as they are ignored by ESLint.
+
+Note that this rule will not be able to warn correctly if you use AVA by specifying the files in the command line ( `ava "lib/**/*.test.js"` ). Prefer configuring AVA as described [here](https://github.com/sindresorhus/ava#configuration).
+
+## Fail
+
+```js
+// File: src/index.js
+// Invalid because *.test.js is considered as a test file.
+import tests from './index.test.js';
+```
+
+```js
+// File: src/index.js
+// Invalid because any files inside __tests__ are considered test files
+import tests from './__tests__/index.js';
+
+test('foo', t => {
+	t.pass();
+});
+```
+
+```js
+// File: utils/index.js
+// with { "files": ["lib/**/*.test.js", "utils/**/*.test.js"] }
+// in either `package.json` under 'ava key' or in the rule options
+// Invalid because the imported file matches lib/**/*.test.js
+import tests from '../lib/index.test.js';
+
+test('foo', t => {
+	t.pass();
+});
+```
+
+
+## Pass
+
+```js
+// File: src/index.js
+import sinon from 'sinon';
+
+```
+
+```js
+// File: src/index.js
+import utils from './utils';
+```
+
+```js
+// File: lib/index.js
+// with { "files": ["lib/**/*.test.js", "utils/**/*.test.js"] }
+// in either `package.json` under 'ava key' or in the rule options
+import utils from '../utils/index.js';
+```
+
+## Options
+
+This rule supports the following options:
+
+`files`: An array of strings representing the files glob that AVA will use to find test files. Overrides the default and the configuration found in the `package.json` file.
+
+You can set the options like this:
+
+```js
+"ava/no-ignored-test-files": ["error", {"files": ["lib/**/*.test.js", "utils/**/*.test.js"]}]
+```

index.js

@@ -21,6 +21,7 @@ module.exports = {
 				'ava/no-duplicate-modifiers': 'error',
 				'ava/no-identical-title': 'error',
 				'ava/no-ignored-test-files': 'error',
+				'ava/no-import-test-files': 'error',
 				'ava/no-invalid-end': 'error',
 				'ava/no-nested-tests': 'error',
 				'ava/no-only-test': 'error',

readme.md

@@ -40,6 +40,7 @@ Configure it in `package.json`.
 			"ava/no-duplicate-modifiers": "error",
 			"ava/no-identical-title": "error",
 			"ava/no-ignored-test-files": "error",
+			"ava/no-import-test-files": "error",
 			"ava/no-invalid-end": "error",
 			"ava/no-nested-tests": "error",
 			"ava/no-only-test": "error",
@@ -74,6 +75,7 @@ The rules will only activate in test files.
 - [no-duplicate-modifiers](docs/rules/no-duplicate-modifiers.md) - Ensure tests do not have duplicate modifiers.
 - [no-identical-title](docs/rules/no-identical-title.md) - Ensure no tests have the same title.
 - [no-ignored-test-files](docs/rules/no-ignored-test-files.md) - Ensure no tests are written in ignored files.
+- [no-import-test-files](docs/rules/no-import-test-files.md) - Ensure no test files are imported anywhere.
 - [no-invalid-end](docs/rules/no-invalid-end.md) - Ensure `t.end()` is only called inside `test.cb()`.
 - [no-nested-tests](docs/rules/no-nested-tests.md) - Ensure no tests are nested.
 - [no-only-test](docs/rules/no-only-test.md) - Ensure no `test.only()` are present. *(fixable)*

rules/no-ignored-test-files.js

@@ -7,14 +7,6 @@ const {visitIf} = require('enhance-visitors');
 const util = require('../util');
 const createAvaRule = require('../create-ava-rule');
 
-const defaultFiles = [
-	'test.js',
-	'test-*.js',
-	'test/**/*.js',
-	'**/__tests__/**/*.js',
-	'**/*.test.js'
-];
-
 const excludedFolders = [
 	'**/fixtures/**',
 	'**/helpers/**'
@@ -53,7 +45,7 @@ const create = context => {
 	const ava = createAvaRule();
 	const packageInfo = getPackageInfo();
 	const options = context.options[0] || {};
-	const files = arrify(options.files || packageInfo.files || defaultFiles);
+	const files = arrify(options.files || packageInfo.files || util.defaultFiles);
 	let hasTestCall = false;
 
 	if (!packageInfo.rootDir) {
@@ -91,10 +83,7 @@ const schema = [{
 	type: 'object',
 	properties: {
 		files: {
-			anyOf: [
-				{type: 'array'},
-				{type: 'string'}
-			]
+			type: 'array',
 		}
 	}
 }];

rules/no-import-test-files.js

@@ -0,0 +1,88 @@
+'use strict';
+const path = require('path');
+const arrify = require('arrify');
+const pkgUp = require('pkg-up');
+const multimatch = require('multimatch');
+const util = require('../util');
+
+function isTestFile(files, rootDir, sourceFile, importedFile) {
+	const absoluteImportedPath = path.resolve(path.dirname(sourceFile), importedFile);
+	const relativePath = path.relative(rootDir, absoluteImportedPath);
+
+	return multimatch([relativePath], files).length === 1;
+}
+
+function getProjectInfo() {
+	const packageFilePath = pkgUp.sync();
+
+	return {
+		rootDir: packageFilePath && path.dirname(packageFilePath),
+		files: util.getAvaConfig(packageFilePath).files
+	};
+}
+
+function createImportValidator(context, files, projectInfo, filename) {
+	return (node, importPath) => {
+		const isImportingTestFile = isTestFile(files, projectInfo.rootDir, filename, importPath);
+
+		if (isImportingTestFile) {
+			context.report({
+				node,
+				message: `Test files should not be imported`
+			});
+		}
+	};
+}
+
+const create = context => {
+	const filename = context.getFilename();
+
+	if (filename === '<text>') {
+		return {};
+	}
+
+	const projectInfo = getProjectInfo();
+	const options = context.options[0] || {};
+	const files = arrify(options.files || projectInfo.files || util.defaultFiles);
+
+	if (!projectInfo.rootDir) {
+		// Could not find a package.json folder
+		return {};
+	}
+
+	const validateImportPath = createImportValidator(context, files, projectInfo, filename);
+
+	return {
+		ImportDeclaration: node => {
+			validateImportPath(node, node.source.value);
+		},
+		CallExpression: node => {
+			if (!(node.callee.type === 'Identifier' && node.callee.name === 'require')) {
+				return;
+			}
+
+			if (node.arguments[0] && node.arguments[0].type === 'Literal') {
+				validateImportPath(node, node.arguments[0].value);
+			}
+		}
+	};
+};
+
+const schema = [{
+	type: 'object',
+	properties: {
+		files: {
+			type: 'array'
+		}
+	}
+}];
+
+module.exports = {
+	create,
+	meta: {
+		docs: {
+			url: util.getDocsUrl(__filename)
+		},
+		schema
+	}
+};

test/no-ignored-test-files-with-package.js

@@ -34,7 +34,7 @@ ruleTester.run('no-ignored-test-files', rule, {
 		{
 			code: code(true),
 			filename: toPath('bar/foo.test.js'),
-			options: [{files: 'bar/**/*.test.js'}]
+			options: [{files: ['bar/**/*.test.js']}]
 		},
 		{
 			code: code(true),
@@ -72,7 +72,7 @@ ruleTester.run('no-ignored-test-files', rule, {
 		{
 			code: code(true),
 			filename: toPath('lib/foo.test.js'),
-			options: [{files: 'bar/**/*.test.js'}],
+			options: [{files: ['bar/**/*.test.js']}],
 			errors: [{message: 'Test file is ignored because it is not in `bar/**/*.test.js`.'}]
 		}
 	]

test/no-import-test-files.js

@@ -0,0 +1,50 @@
+import path from 'path';
+import test from 'ava';
+import avaRuleTester from 'eslint-ava-rule-tester';
+import util from '../util';
+import rule from '../rules/no-import-test-files';
+
+const ruleTester = avaRuleTester(test, {
+	env: {
+		es6: true
+	},
+	parserOptions: {
+		sourceType: 'module'
+	}
+});
+
+const rootDir = path.dirname(__dirname);
+const toPath = subPath => path.join(rootDir, subPath);
+
+util.getAvaConfig = () => ({
+	files: ['lib/*.test.js']
+});
+
+ruleTester.run('no-import-test-files', rule, {
+	valid: [
+		{
+			code: 'import test from \'ava\';'
+		},
+		{
+			code: 'const test = require(\'ava\');'
+		},
+		{
+			code: 'console.log()'
+		},
+		{
+			code: 'const value = require(somePath);'
+		}
+	],
+	invalid: [
+		{
+			code: 'const test = require(\'./foo.test.js\');',
+			filename: toPath('lib/foo.js'),
+			errors: [{message: 'Test files should not be imported'}]
+		},
+		{
+			code: 'import test from \'./foo.test.js\';',
+			filename: toPath('lib/foo.js'),
+			errors: [{message: 'Test files should not be imported'}]
+		}
+	]
+});

util.js

@@ -13,6 +13,14 @@ const functionExpressions = [
 	'ArrowFunctionExpression'
 ];
 
+const defaultFiles = [
+	'test.js',
+	'test-*.js',
+	'test/**/*.js',
+	'**/__tests__/**/*.js',
+	'**/*.test.js'
+];
+
 exports.nameOfRootObject = node => {
 	if (node.object.type === 'MemberExpression') {
 		return exports.nameOfRootObject(node.object);
@@ -172,5 +180,6 @@ const assertionMethodsNumArguments = new Map([
 const assertionMethodNames = [...assertionMethodsNumArguments.keys()];
 
 exports.assertionMethodsNumArguments = assertionMethodsNumArguments;
+exports.defaultFiles = defaultFiles;
 exports.assertionMethods = new Set(assertionMethodNames);
 exports.executionMethods = new Set(assertionMethodNames.concat(['end', 'plan', 'log']));