fix: Fixed bug when file not defined in tsconfig

Author: roman.vasilev

package.json

@@ -23,6 +23,7 @@
     "test": "npm run tscheck && npm run test:r",
     "tscheck": "echo tscheck... && tsc --noEmit",
     "test:r": "jest --runInBand --verbose",
+    "test:w": "jest --watch --runInBand",
     "semantic-release": "semantic-release",
     "prepublishOnly": "npm run build && sed -i -e 's/devDependencies/_devDependencies/g' package.json",
     "build": "tsc",

src/custom-linter.ts

@@ -0,0 +1,23 @@
+import * as ts from 'typescript';
+import { ILinterOptions, LintResult } from 'tslint';
+import { typescriptService } from './typescript-service';
+const { Linter: TSLintLinter } = require('tslint');
+
+export class CustomLinter extends TSLintLinter {
+
+    constructor(options: ILinterOptions, program?: ts.Program | undefined) {
+        super(options, program);
+    }
+
+    getResult(): LintResult {
+        return super.getResult();
+    }
+
+    getSourceFile(fileName: string, source: string) {
+        if (this.program === undefined) {
+            return super.getSourceFile(fileName, source);
+        }
+        const service = typescriptService();
+        return service.getSourceFile(fileName);
+    }
+}

src/index.ts

@@ -7,10 +7,12 @@
 // Requirements
 //------------------------------------------------------------------------------
 
-import { Linter as TSLintLinter, RuleSeverity, Configuration } from 'tslint';
+import { RuleSeverity, Configuration } from 'tslint';
 import * as ts from 'typescript';
 import { Rule } from 'eslint';
-import { createService } from 'typescript-service';
+import { typescriptService } from './typescript-service';
+import { CustomLinter } from './custom-linter';
+
 
 //------------------------------------------------------------------------------
 // Plugin Definition
@@ -35,8 +37,6 @@ interface TSLintPluginOptions {
     rules?: RawRulesConfig;
 }
 
-let languageService: ReturnType<typeof createService>;
-
 export const rules = {
     /**
      * Expose a single rule called "config", which will be accessed in the user's eslint config files
@@ -110,16 +110,14 @@ export const rules = {
             let program: ts.Program | undefined = undefined;
 
             if (fileName !== '<input>' && configFile) {
-                if (!languageService) {
-                    languageService = createService({ configFile, compilerOptions });
-                }
-                program = languageService.getProgram();
+                const service = typescriptService({ configFile, compilerOptions });
+                program = service.getProgram();
             }
 
             /**
              * Create an instance of TSLint
              */
-            const tslint = new TSLintLinter(tslintOptions, program);
+            const tslint = new CustomLinter(tslintOptions, program);
 
             /**
              * Lint the source code using the configured TSLint instance, and the rules which have been

src/typescript-service.ts

@@ -0,0 +1,19 @@
+import { createService } from 'typescript-service';
+import * as ts from 'typescript';
+
+let service: ReturnType<typeof createService>;
+
+type createServiceOptions = {
+    configFile: string;
+    compilerOptions?: ts.CompilerOptions;
+};
+
+export function typescriptService(options?: createServiceOptions) {
+    if (service === undefined) {
+        if (options === undefined) {
+            throw new Error('Service is not yet created');
+        }
+        service = createService(options);
+    }
+    return service;
+}

test/index.spec.ts

@@ -47,6 +47,18 @@ ruleTester.run('tslint/config', rules.config, {
             parserOptions,
             options: [tslintRulesConfig],
         },
+        {
+            filename: './test/test-project/file-spec.ts',
+            code: '/* file not defined in tsconfig */',
+            parser: 'typescript-eslint-parser',
+            parserOptions,
+            options: [
+                {
+                    ...tslintRulesConfig,
+                    configFile: `${__dirname}/test-project/tsconfig-files.json`,
+                },
+            ],
+        },
     ],
 
     invalid: [

test/test-project/file-spec.ts

@@ -0,0 +1,2 @@
+import { x } from './file';
+console.assert(x);

test/test-project/file.ts

@@ -0,0 +1,3 @@
+import * as number from './number';
+export const x = 1;
+console.log(number);

test/test-project/tsconfig-files.json

@@ -0,0 +1,6 @@
+{
+  "lib": ["dom"],
+  "files": [
+    "file.ts"
+  ]
+}