fix(typescript-estree): improve error messaging around project files

packages/typescript-estree/jest.config.js

@@ -10,4 +10,12 @@ module.exports = {
   collectCoverageFrom: ['src/**/*.{js,jsx,ts,tsx}'],
   moduleFileExtensions: ['ts', 'tsx', 'js', 'jsx', 'json', 'node'],
   coverageReporters: ['text-summary', 'lcov'],
+  globals: {
+    'ts-jest': {
+      diagnostics: {
+        // ignore the diagnostic error for the invalidFileErrors fixtures
+        ignoreCodes: [5056],
+      },
+    },
+  },
 };

packages/typescript-estree/src/convert.ts

@@ -67,7 +67,7 @@ export class Converter {
    */
   constructor(ast: ts.SourceFile, options: ConverterOptions) {
     this.ast = ast;
-    this.options = options;
+    this.options = { ...options };
   }
 
   getASTMaps(): ASTMaps {

packages/typescript-estree/src/parser.ts

@@ -1,3 +1,4 @@
+import path from 'path';
 import semver from 'semver';
 import * as ts from 'typescript'; // leave this as * as ts so people using util package don't need syntheticDefaultImports
 import { astConverter } from './ast-converter';
@@ -9,6 +10,7 @@ import { TSESTree } from './ts-estree';
 import {
   calculateProjectParserOptions,
   createProgram,
+  defaultCompilerOptions,
 } from './tsconfig-parser';
 
 /**
@@ -87,9 +89,39 @@ function getASTFromProject(
   );
 
   if (!astAndProgram && !createDefaultProgram) {
-    throw new Error(
-      `If "parserOptions.project" has been set for @typescript-eslint/parser, ${filePath} must be included in at least one of the projects provided.`,
-    );
+    // the file was either not matched within the tsconfig, or the extension wasn't expected
+    const errorLines = [
+      '"parserOptions.project" has been set for @typescript-eslint/parser.',
+      `The file does not match your project config: ${filePath}.`,
+    ];
+    let hasMatchedAnError = false;
+
+    const fileExtension = path.extname(filePath);
+    if (!['.ts', '.tsx', '.js', '.jsx'].includes(fileExtension)) {
+      const nonStandardExt = `The extension for the file (${fileExtension}) is non-standard`;
+      if (extra.extraFileExtensions && extra.extraFileExtensions.length > 0) {
+        if (!extra.extraFileExtensions.includes(fileExtension)) {
+          errorLines.push(
+            `${nonStandardExt}. It should be added to your existing "parserOptions.extraFileExtensions".`,
+          );
+          hasMatchedAnError = true;
+        }
+      } else {
+        errorLines.push(
+          `${nonStandardExt}. You should add "parserOptions.extraFileExtensions" to your config.`,
+        );
+        hasMatchedAnError = true;
+      }
+    }
+
+    if (!hasMatchedAnError) {
+      errorLines.push(
+        'The file must be included in at least one of the projects provided.',
+      );
+      hasMatchedAnError = true;
+    }
+
+    throw new Error(errorLines.join('\n'));
   }
 
   return astAndProgram;
@@ -158,6 +190,7 @@ function createNewProgram(code: string): ASTAndProgram {
       noResolve: true,
       target: ts.ScriptTarget.Latest,
       jsx: extra.jsx ? ts.JsxEmit.Preserve : undefined,
+      ...defaultCompilerOptions,
     },
     compilerHost,
   );

packages/typescript-estree/src/tsconfig-parser.ts

@@ -9,9 +9,10 @@ import { Extra } from './parser-options';
 /**
  * Default compiler options for program generation from single root file
  */
-const defaultCompilerOptions: ts.CompilerOptions = {
+export const defaultCompilerOptions: ts.CompilerOptions = {
   allowNonTsExtensions: true,
   allowJs: true,
+  checkJs: true,
 };
 
 /**
@@ -109,7 +110,7 @@ export function calculateProjectParserOptions(
     // create compiler host
     const watchCompilerHost = ts.createWatchCompilerHost(
       tsconfigPath,
-      /*optionsToExtend*/ { allowNonTsExtensions: true } as ts.CompilerOptions,
+      defaultCompilerOptions,
       ts.sys,
       ts.createSemanticDiagnosticsBuilderProgram,
       diagnosticReporter,

packages/typescript-estree/tests/fixtures/invalidFileErrors/js/included.js

@@ -0,0 +1 @@
+export var a = true;

packages/typescript-estree/tests/fixtures/invalidFileErrors/js/included.jsx

@@ -0,0 +1 @@
+export var a = true;

packages/typescript-estree/tests/fixtures/invalidFileErrors/js/notIncluded.js

@@ -0,0 +1 @@
+export var a = true;

packages/typescript-estree/tests/fixtures/invalidFileErrors/js/notIncluded.jsx

@@ -0,0 +1 @@
+export var a = true;

packages/typescript-estree/tests/fixtures/invalidFileErrors/other/included.vue

@@ -0,0 +1 @@
+export var a = true;

packages/typescript-estree/tests/fixtures/invalidFileErrors/other/notIncluded.vue

@@ -0,0 +1 @@
+export var a = true;

packages/typescript-estree/tests/fixtures/invalidFileErrors/other/unknownFileType.unknown

@@ -0,0 +1 @@
+export var a = true;

packages/typescript-estree/tests/fixtures/invalidFileErrors/ts/included.ts

@@ -0,0 +1 @@
+export var a = true;

packages/typescript-estree/tests/fixtures/invalidFileErrors/ts/included.tsx

@@ -0,0 +1 @@
+export var a = true;

packages/typescript-estree/tests/fixtures/invalidFileErrors/ts/notIncluded.ts

@@ -0,0 +1 @@
+export var a = true;

packages/typescript-estree/tests/fixtures/invalidFileErrors/ts/notIncluded.tsx

@@ -0,0 +1 @@
+export var a = true;

packages/typescript-estree/tests/fixtures/invalidFileErrors/tsconfig.json

@@ -0,0 +1,9 @@
+{
+  "include": [
+    "ts/included.ts",
+    "ts/included.tsx",
+    "js/included.js",
+    "js/included.jsx",
+    "other/included.vue"
+  ]
+}

packages/typescript-estree/tests/lib/__snapshots__/parse.ts.snap

@@ -189,6 +189,42 @@ Object {
 }
 `;
 
+exports[`parse() invalid file error messages "parserOptions.extraFileExtensions" is non-empty the extension does not match 1`] = `
+"\\"parserOptions.project\\" has been set for @typescript-eslint/parser.
+The file does not match your project config: tests/fixtures/invalidFileErrors/other/unknownFileType.unknown.
+The extension for the file (.unknown) is non-standard. It should be added to your existing \\"parserOptions.extraFileExtensions\\"."
+`;
+
+exports[`parse() invalid file error messages "parserOptions.extraFileExtensions" is non-empty the extension matches the file isn't included 1`] = `
+"\\"parserOptions.project\\" has been set for @typescript-eslint/parser.
+The file does not match your project config: tests/fixtures/invalidFileErrors/other/notIncluded.vue.
+The file must be included in at least one of the projects provided."
+`;
+
+exports[`parse() invalid file error messages project includes errors for not included files 1`] = `
+"\\"parserOptions.project\\" has been set for @typescript-eslint/parser.
+The file does not match your project config: tests/fixtures/invalidFileErrors/ts/notIncluded.ts.
+The file must be included in at least one of the projects provided."
+`;
+
+exports[`parse() invalid file error messages project includes errors for not included files 2`] = `
+"\\"parserOptions.project\\" has been set for @typescript-eslint/parser.
+The file does not match your project config: tests/fixtures/invalidFileErrors/ts/notIncluded.tsx.
+The file must be included in at least one of the projects provided."
+`;
+
+exports[`parse() invalid file error messages project includes errors for not included files 3`] = `
+"\\"parserOptions.project\\" has been set for @typescript-eslint/parser.
+The file does not match your project config: tests/fixtures/invalidFileErrors/js/notIncluded.js.
+The file must be included in at least one of the projects provided."
+`;
+
+exports[`parse() invalid file error messages project includes errors for not included files 4`] = `
+"\\"parserOptions.project\\" has been set for @typescript-eslint/parser.
+The file does not match your project config: tests/fixtures/invalidFileErrors/js/notIncluded.jsx.
+The file must be included in at least one of the projects provided."
+`;
+
 exports[`parse() non string code should correctly convert code to a string for parse() 1`] = `
 Object {
   "body": Array [

packages/typescript-estree/tests/lib/parse.ts

@@ -1,8 +1,8 @@
+import { join, resolve, relative } from 'path';
 import * as parser from '../../src/parser';
 import * as astConverter from '../../src/ast-converter';
 import { TSESTreeOptions } from '../../src/parser-options';
 import { createSnapshotTestBlock } from '../../tools/test-utils';
-import { join } from 'path';
 
 const FIXTURES_DIR = './tests/fixtures/simpleProject';
 
@@ -145,7 +145,7 @@ describe('parse()', () => {
     };
     const projectConfig: TSESTreeOptions = {
       ...baseConfig,
-      tsconfigRootDir: join(process.cwd(), FIXTURES_DIR),
+      tsconfigRootDir: FIXTURES_DIR,
       project: './tsconfig.json',
     };
 
@@ -241,4 +241,60 @@ describe('parse()', () => {
       ).toBeUndefined();
     });
   });
+
+  describe('invalid file error messages', () => {
+    const PROJECT_DIR = resolve(FIXTURES_DIR, '../invalidFileErrors');
+    const code = 'var a = true';
+    const config: TSESTreeOptions = {
+      comment: true,
+      tokens: true,
+      range: true,
+      loc: true,
+      tsconfigRootDir: PROJECT_DIR,
+      project: './tsconfig.json',
+      extraFileExtensions: ['.vue'],
+    };
+    const testParse = (filePath: string) => (): void => {
+      parser.parseAndGenerateServices(code, {
+        ...config,
+        filePath: relative(process.cwd(), join(PROJECT_DIR, filePath)),
+      });
+    };
+
+    describe('project includes', () => {
+      it("doesn't error for matched files", () => {
+        expect(testParse('ts/included.ts')).not.toThrow();
+        expect(testParse('ts/included.tsx')).not.toThrow();
+        expect(testParse('js/included.js')).not.toThrow();
+        expect(testParse('js/included.jsx')).not.toThrow();
+      });
+
+      it('errors for not included files', () => {
+        expect(testParse('ts/notIncluded.ts')).toThrowErrorMatchingSnapshot();
+        expect(testParse('ts/notIncluded.tsx')).toThrowErrorMatchingSnapshot();
+        expect(testParse('js/notIncluded.js')).toThrowErrorMatchingSnapshot();
+        expect(testParse('js/notIncluded.jsx')).toThrowErrorMatchingSnapshot();
+      });
+    });
+
+    describe('"parserOptions.extraFileExtensions" is non-empty', () => {
+      describe('the extension matches', () => {
+        it('the file is included', () => {
+          expect(testParse('other/included.vue')).not.toThrow();
+        });
+
+        it("the file isn't included", () => {
+          expect(
+            testParse('other/notIncluded.vue'),
+          ).toThrowErrorMatchingSnapshot();
+        });
+      });
+
+      it('the extension does not match', () => {
+        expect(
+          testParse('other/unknownFileType.unknown'),
+        ).toThrowErrorMatchingSnapshot();
+      });
+    });
+  });
 });