feat: report typescript diagnostics (optional)

package.json

@@ -40,6 +40,7 @@
     "@types/node": "^18.0.0",
     "@typescript-eslint/eslint-plugin": "^5.29.0",
     "@typescript-eslint/parser": "^5.29.0",
+    "byots": "^4.8.0-dev.20220707.1.35",
     "eslint": "^8.18.0",
     "eslint-config-prettier": "^8.5.0",
     "lint-staged": "^13.0.3",

src/plugin/error.ts

@@ -0,0 +1,32 @@
+export function createErrorString({
+  message,
+  file,
+  line,
+  column,
+}: {
+  message: string;
+  file: string;
+  line: number;
+  column: number;
+}) {
+  return `
+// error generated by vite-plugin-vitest-typescript-assert
+(() => {
+  const err = new TypeError("${message}");
+  err.name = "TypeError";
+  err.stack = "";
+  err.stackStr = "";
+  err.stacks = [{
+    file: "${file}",
+    line: ${line + 1},
+    column: ${column},
+    sourcePos: {
+      source: "${file}",
+      line: ${line + 1},
+      column: ${column}
+    }
+  }];
+  throw err;
+})()
+`;
+}

src/plugin/identifiers.ts

@@ -0,0 +1,28 @@
+// TODO: should be set by user config?!
+export const testWrapperIdentifiers = [
+  'it',
+  'it.skip',
+  'it.skipIf',
+  'it.runIf',
+  'it.only',
+  'it.concurrent',
+  'it.todo',
+  'it.fails',
+  'it.each',
+  'test',
+  'test.skip',
+  'test.skipIf',
+  'test.runIf',
+  'test.only',
+  'test.concurrent',
+  'test.todo',
+  'test.fails',
+  'test.each',
+  'describe',
+  'describe.skip',
+  'describe.only',
+  'describe.concurrent',
+  'describe.shuffle',
+  'describe.todo',
+  'describe.each',
+];

src/plugin/index.ts

@@ -31,7 +31,12 @@ export function vitestTypescriptAssertPlugin(options: PluginOptions = {}): Plugi
         return;
       }
 
-      return transform({ code, fileName, tsconfig: tsconfig.config });
+      return transform({
+        code,
+        fileName,
+        tsconfig: tsconfig.config,
+        shouldReportDiagnostics: !!typescript?.shouldReportDiagnostics,
+      });
     },
   };
 }

src/plugin/transform.ts

@@ -1,18 +1,23 @@
-import type ts from 'typescript';
+import type ts from 'byots';
 import MagicString from 'magic-string';
+import { reportDiagnostics } from './util';
 import type { TransformResult } from 'vite';
+import { program } from '../typescript/program';
 
 export interface TransformOptions {
   code: string;
   fileName: string;
   tsconfig: ts.ParsedCommandLine;
+  shouldReportDiagnostics?: boolean;
 }
 
-export function transform({ code, fileName, tsconfig }: TransformOptions): TransformResult {
+export function transform({ code, fileName, tsconfig, shouldReportDiagnostics }: TransformOptions): TransformResult {
+  const { diagnostics } = program({ config: tsconfig, fileName });
   const newCode = new MagicString(code);
 
-  // eslint-disable-next-line no-console
-  console.log({ fileName, tsconfig });
+  if (shouldReportDiagnostics) {
+    reportDiagnostics(diagnostics, newCode, fileName);
+  }
 
   return {
     code: newCode.toString(),

src/plugin/util.ts

@@ -0,0 +1,53 @@
+import ts from 'byots';
+import type MagicString from 'magic-string';
+import { createErrorString } from './error';
+import { newLine } from '../typescript/util';
+import { testWrapperIdentifiers } from './identifiers';
+
+export function searchTestWrapperFromPosition(file: ts.SourceFile, position: number) {
+  const token = ts.getTokenAtPosition(file, position);
+
+  let parent: ts.Node | undefined = token.parent;
+
+  while (parent) {
+    if (ts.isCallExpression(parent)) {
+      const expression = parent.expression;
+      const identifier = expression.getText();
+
+      if (testWrapperIdentifiers.includes(identifier)) {
+        const name = parent.arguments[0]?.getText().slice(1, -1);
+        const handler = parent.arguments[1];
+
+        if (name && handler) {
+          return { name, expression, handler };
+        }
+      }
+
+      parent = undefined;
+    }
+
+    parent = parent?.parent;
+  }
+
+  return undefined;
+}
+
+export function reportDiagnostics(diagnostics: readonly ts.Diagnostic[], newCode: MagicString, fileName: string) {
+  if (diagnostics[0]) {
+    const { messageText, start, file } = diagnostics[0];
+
+    if (file) {
+      const startPosition = start ?? -1;
+      const message = ts.flattenDiagnosticMessageText(messageText, newLine);
+      const { line, character } = ts.getLineAndCharacterOfPosition(file, startPosition);
+      const token = searchTestWrapperFromPosition(file, startPosition);
+
+      if (token) {
+        const position = token.handler.getEnd() - 1;
+        newCode.appendLeft(position, createErrorString({ message, file: fileName, line, column: character }));
+      } else {
+        newCode.append(createErrorString({ message, file: fileName, line, column: character }));
+      }
+    }
+  }
+}

src/typescript/config.ts

@@ -1,5 +1,5 @@
 import path from 'path';
-import ts from 'typescript';
+import ts from 'byots';
 import { formatDiagnostics } from './diagnostic';
 import { errorMessage, ErrorCode } from '../error';
 import { getCurrentDirectory, fileExists, readFile } from './util';
@@ -8,6 +8,7 @@ export interface TypeScriptConfigOptions {
   configName?: string;
   searchPath?: string;
   compilerOptions?: ts.CompilerOptions;
+  shouldReportDiagnostics?: boolean;
 }
 
 export function findConfigFile(options: TypeScriptConfigOptions = {}) {
@@ -88,13 +89,3 @@ export function loadConfig(options?: TypeScriptConfigOptions) {
     return { error: error as Error };
   }
 }
-
-export function getCompilerOptions(options?: TypeScriptConfigOptions, compilerOptions?: ts.CompilerOptions) {
-  return {
-    ...ts.getDefaultCompilerOptions(),
-    strict: true,
-    target: ts.ScriptTarget.Latest,
-    ...(options?.compilerOptions ?? {}),
-    ...(compilerOptions ?? {}),
-  } as ts.CompilerOptions;
-}

src/typescript/diagnostic.ts

@@ -1,4 +1,4 @@
-import ts from 'typescript';
+import ts from 'byots';
 import { getCurrentDirectory, newLine } from './util';
 
 export const diagnosticsHost: ts.FormatDiagnosticsHost = {

src/typescript/program.ts

@@ -0,0 +1,10 @@
+import ts from 'byots';
+
+export function program({ fileName, config }: { fileName: string; config: ts.ParsedCommandLine }) {
+  const compilerOptions = { ...ts.getDefaultCompilerOptions(), ...config.options };
+  const program = ts.createProgram([fileName], compilerOptions);
+  const diagnostics = ts.getPreEmitDiagnostics(program);
+  const checker = program.getTypeChecker();
+
+  return { program, diagnostics, checker };
+}

src/typescript/util.ts

@@ -1,6 +1,6 @@
-import ts from 'typescript';
+import ts from 'byots';
 
-export const newLine = '\r\n';
+export const newLine = '\n';
 
 export function getCurrentDirectory() {
   return ts.sys.getCurrentDirectory();
@@ -13,3 +13,8 @@ export function fileExists(fileName: string) {
 export function readFile(fileName: string) {
   return ts.sys.readFile(fileName);
 }
+
+export function getMiddle(node: ts.Node) {
+  const diff = node.getEnd() - node.getStart();
+  return node.getStart() + Math.round(diff / 2);
+}

test/index.test.ts

@@ -1,11 +1,21 @@
 import { test, expect, describe } from 'vitest';
 
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+const prout1 = 'plop';
+
 test('test-1', () => {
   expect('Hello World').toBe(42);
+
+  // const prout2 = 'plop';
 });
 
-describe('test-2', () => {
-  test('test-2', () => {
-    expect('Hello World').toBe(24);
+describe('describe-1', () => {
+  // const prout3 = 'plop';
+
+  test('test-3', () => {
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    const prout4 = 'plop';
+
+    // expect('Hello World').toBe(24);
   });
 });

vitest.config.ts

@@ -2,5 +2,9 @@ import { defineConfig } from 'vitest/config';
 import { vitestTypescriptAssertPlugin } from './src';
 
 export default defineConfig({
-  plugins: [vitestTypescriptAssertPlugin()],
+  plugins: [
+    vitestTypescriptAssertPlugin({
+      typescript: { shouldReportDiagnostics: true },
+    }),
+  ],
 });