phenomnomnominal · phenomnomnominal · Feb 22, 2021 · Feb 22, 2021
diff --git a/.betterer.results b/.betterer.results
@@ -4,7 +4,7 @@ exports[`no hack comments`] = {
     "packages/cli/src/cli.ts:1074837834": [
       [13, 0, 7, "RegExp match", "645651780"]
     ],
-    "packages/cli/src/init/update-package-json.ts:2842907794": [
+    "packages/cli/src/init/update-package-json.ts:887451963": [
       [34, 4, 7, "RegExp match", "645651780"]
     ]
   }`

diff --git a/README.md b/README.md
@@ -183,16 +183,16 @@ betterer -c ./path/to/config -r ./path/to/results -w
 
 #### Start options
 
-| Name                           | Description                                                                 | Default               |
-| ------------------------------ | --------------------------------------------------------------------------- | --------------------- |
-| `-c`, `--config` [value]       | Path to test definition file relative to CWD. Takes multiple values         | `./.betterer.ts`      |
-| `-r`, `--results` [value]      | Path to test results file relative to CWD                                   | `./.betterer.results` |
-| `-t`, `--tsconfig` [value]     | Path to TypeScript config file relative to CWD                              | `null`                |
-| `-f`, `--filter` [value]       | Select tests to run by RegExp. Takes multiple values                        | `[]`                  |
-| `-s`, `--silent [true\|false]` | Disable all default reporters. Custom reporters still work normally         | `false`               |
-| `-u`, `--update [true\|false]` | Force update the results file, even if things get worse                     | `false`               |
-| `--allow-update [true\|false]` | Allow updating via the `--update` flag                                      | `true`                |
-| `-R`, `--reporter` [value]     | npm package name or file path to a Betterer reporter. Takes multiple values | Default reporter      |
+| Name                       | Description                                                                                        | Default               |
+| -------------------------- | -------------------------------------------------------------------------------------------------- | --------------------- |
+| `-c`, `--config` [value]   | Path to test definition file relative to CWD. Takes multiple values                                | `./.betterer.ts`      |
+| `-r`, `--results` [value]  | Path to test results file relative to CWD                                                          | `./.betterer.results` |
+| `-t`, `--tsconfig` [value] | Path to TypeScript config file relative to CWD                                                     | `null`                |
+| `-f`, `--filter` [value]   | Select tests to run by RegExp. Takes multiple values                                               | `[]`                  |
+| `-s`, `--silent`           | When present, all default reporters will be disabled. Custom reporters will still work normally.   | `false`               |
+| `-u`, `--update`           | When present, the results file will be updated, even if things get worse                           | `false`               |
+| `--allow-update`           | When set to false, the update message will not be shown and the `--update` option will be ignored. | `true`                |
+| `-R`, `--reporter` [value] | npm package name or file path to a Betterer reporter. Takes multiple values                        | Default reporter      |
 
 ### CI
 

diff --git a/packages/cli/README.md b/packages/cli/README.md
@@ -32,16 +32,16 @@ betterer -c ./path/to/config -r ./path/to/results -w
 
 #### Start options
 
-| Name                           | Description                                                                 | Default               |
-| ------------------------------ | --------------------------------------------------------------------------- | --------------------- |
-| `-c`, `--config` [value]       | Path to test definition file relative to CWD. Takes multiple values         | `./.betterer.ts`      |
-| `-r`, `--results` [value]      | Path to test results file relative to CWD                                   | `./.betterer.results` |
-| `-t`, `--tsconfig` [value]     | Path to TypeScript config file relative to CWD                              | `null`                |
-| `-f`, `--filter` [value]       | Select tests to run by RegExp. Takes multiple values                        | `[]`                  |
-| `-s`, `--silent [true\|false]` | Disable all default reporters. Custom reporters still work normally         | `false`               |
-| `-u`, `--update [true\|false]` | Force update the results file, even if things get worse                     | `false`               |
-| `--allow-update [true\|false]` | Allow updating via the `--update` flag                                      | `true`                |
-| `-R`, `--reporter` [value]     | npm package name or file path to a Betterer reporter. Takes multiple values | Default reporter      |
+| Name                       | Description                                                                                        | Default               |
+| -------------------------- | -------------------------------------------------------------------------------------------------- | --------------------- |
+| `-c`, `--config` [value]   | Path to test definition file relative to CWD. Takes multiple values                                | `./.betterer.ts`      |
+| `-r`, `--results` [value]  | Path to test results file relative to CWD                                                          | `./.betterer.results` |
+| `-t`, `--tsconfig` [value] | Path to TypeScript config file relative to CWD                                                     | `null`                |
+| `-f`, `--filter` [value]   | Select tests to run by RegExp. Takes multiple values                                               | `[]`                  |
+| `-s`, `--silent`           | When present, all default reporters will be disabled. Custom reporters will still work normally.   | `false`               |
+| `-u`, `--update`           | When present, the results file will be updated, even if things get worse                           | `false`               |
+| `--allow-update [false]`   | When set to false, the update message will not be shown and the `--update` option will be ignored. | `true`                |
+| `-R`, `--reporter` [value] | npm package name or file path to a Betterer reporter. Takes multiple values                        | Default reporter      |
 
 ### CI
 

diff --git a/packages/cli/src/init.tsx b/packages/cli/src/init.tsx
@@ -1,14 +1,23 @@
-import { render } from 'ink';
 import React from 'react';
 
+import { render } from 'ink';
+import path from 'path';
+
 import { Init } from './init/init';
 import { initOptions } from './options';
 import { BettererCLIArguments } from './types';
 
+const BETTERER_TS = './.betterer.ts';
+const TS_EXTENSION = '.ts';
+
 /** @internal Definitely not stable! Please don't use! */
 export async function initΔ(cwd: string, argv: BettererCLIArguments): Promise<void> {
   const { config } = initOptions(argv);
 
-  const app = render(<Init config={config} cwd={cwd} />);
+  const finalConfig = config || BETTERER_TS;
+  const ext = path.extname(finalConfig);
+  const ts = ext === TS_EXTENSION;
+
+  const app = render(<Init config={finalConfig} cwd={cwd} ts={ts} />);
   await app.waitUntilExit();
 }
diff --git a/packages/cli/src/init/create-test-file.ts b/packages/cli/src/init/create-test-file.ts
@@ -2,11 +2,16 @@ import { BettererError } from '@betterer/errors';
 import { BettererLogger } from '@betterer/logger';
 import { promises as fs } from 'fs';
 
-const TEMPLATE = `export default {
+const TEMPLATE_JS = `module.exports = {
   // Add tests here ☀️
-};`;
+};
+`;
+const TEMPLATE_TS = `export default {
+  // Add tests here ☀️
+};
+`;
 
-export async function run(logger: BettererLogger, configPath: string): Promise<void> {
+export async function run(logger: BettererLogger, configPath: string, ts: boolean): Promise<void> {
   await logger.progress(`creating "${configPath}" file...`);
 
   let exists = false;
@@ -22,7 +27,8 @@ export async function run(logger: BettererLogger, configPath: string): Promise<v
   }
 
   try {
-    await fs.writeFile(configPath, TEMPLATE, 'utf8');
+    const template = ts ? TEMPLATE_TS : TEMPLATE_JS;
+    await fs.writeFile(configPath, template, 'utf8');
     await logger.info(`created "${configPath}"!`);
   } catch {
     throw new BettererError(`could not read "${configPath}".`);

diff --git a/packages/cli/src/init/init.tsx b/packages/cli/src/init/init.tsx
@@ -9,9 +9,10 @@ const updatePackageJSON = workerRequire<WorkerModule<typeof import('./update-pac
 export type InitProps = {
   config: string;
   cwd: string;
+  ts: boolean;
 };
 
-export const Init: FC<InitProps> = function Init({ cwd, config }) {
+export const Init: FC<InitProps> = function Init({ cwd, config, ts }) {
   return (
     <BettererTasksLogger
       name="Initialising Betterer"
@@ -20,14 +21,14 @@ export const Init: FC<InitProps> = function Init({ cwd, config }) {
         {
           name: 'Create test file',
           run: async (logger) => {
-            await createTestFile.run(logger, path.resolve(cwd, config));
+            await createTestFile.run(logger, path.resolve(cwd, config), ts);
             createTestFile.destroy();
           }
         },
         {
           name: 'Update package.json',
           run: async (logger) => {
-            await updatePackageJSON.run(logger, cwd);
+            await updatePackageJSON.run(logger, cwd, ts);
             updatePackageJSON.destroy();
           }
         }

diff --git a/packages/cli/src/init/update-package-json.ts b/packages/cli/src/init/update-package-json.ts
@@ -5,7 +5,7 @@ import { promises as fs } from 'fs';
 
 import { BettererPackageJSON } from '../types';
 
-export async function run(logger: BettererLogger, cwd: string): Promise<void> {
+export async function run(logger: BettererLogger, cwd: string, ts: boolean): Promise<void> {
   await logger.progress('adding "betterer" to package.json file...');
 
   let packageJSON;
@@ -41,6 +41,15 @@ export async function run(logger: BettererLogger, cwd: string): Promise<void> {
     await logger.info('added "@betterer/cli" dependency to package.json file');
   }
 
+  if (ts) {
+    if (packageJSON.devDependencies['typescript']) {
+      await logger.warn('"typescript" dependency already exists, moving on...');
+    } else {
+      packageJSON.devDependencies['typescript'] = `^4`;
+      await logger.info('added "typescript" dependency to package.json file');
+    }
+  }
+
   try {
     await fs.writeFile(packageJSONPath, `${JSON.stringify(packageJSON, null, 2)}\n`, 'utf-8');
   } catch {

diff --git a/packages/cli/src/options.ts b/packages/cli/src/options.ts
@@ -63,7 +63,7 @@ function setEnv<T extends BettererCLIEnvConfig>(argv: BettererCLIArguments): T {
 }
 
 function configPathOption(): void {
-  commander.option('-c, --config [value]', 'Path to test definition file relative to CWD', './.betterer.ts');
+  commander.option('-c, --config [value]', 'Path to test definition file relative to CWD');
 }
 
 function configPathsOption(): void {
@@ -98,20 +98,27 @@ function reportersOption(): void {
   );
 }
 
-function handleBool(val: string) {
-  return val !== 'false';
+function silentOption(): void {
+  commander.option(
+    '-s, --silent',
+    'When present, all default reporters will be disabled. Custom reporters will still work normally.'
+  );
 }
 
-function silentOption(): void {
-  commander.option('-s, --silent [true|false]', 'Disable all default reporters. Custom reporters still work normally.');
+function defaultToTrue(val: string) {
+  return val !== 'false';
 }
 
 function allowUpdateOption(): void {
-  commander.option('--allow-update [true|false]', 'Whether to allow the `--update` option or not.', handleBool);
+  commander.option(
+    '--allow-update [true|false]',
+    'When set to false, the update message will not be shown and the `--update` option will be ignored.',
+    defaultToTrue
+  );
 }
 
 function updateOption(): void {
-  commander.option('-u, --update [true|false]', 'Force update the results file, even if things get worse', handleBool);
+  commander.option('-u, --update', 'When present, the results file will be updated, even if things get worse');
 }
 
 function argsToArray(value: string, previous: BettererCLIArguments = []): BettererCLIArguments {

diff --git a/test/cli/__snapshots__/betterer-init.spec.ts.snap b/test/cli/__snapshots__/betterer-init.spec.ts.snap
@@ -8,6 +8,19 @@ Array [
 ✅ Update package.json: done!
 ・ added \\"betterer\\" script to package.json file.
 ・ added \\"@betterer/cli\\" dependency to package.json file
+・ added \\"typescript\\" dependency to package.json file
+",
+]
+`;
+
+exports[`betterer cli should initialise betterer in a repo with JS 1`] = `
+Array [
+  "🎉 Initialising Betterer (0ms): 2 tasks done!
+✅ Create test file: done!
+・ created \\"<project>/fixtures/test-betterer-init-js/.betterer.js\\"!
+✅ Update package.json: done!
+・ added \\"betterer\\" script to package.json file.
+・ added \\"@betterer/cli\\" dependency to package.json file
 ",
 ]
 `;
@@ -20,13 +33,15 @@ Array [
 ✅ Update package.json: done!
 ・ added \\"betterer\\" script to package.json file.
 ・ added \\"@betterer/cli\\" dependency to package.json file
+・ added \\"typescript\\" dependency to package.json file
 ",
   "🎉 Initialising Betterer (0ms): 2 tasks done!
 ✅ Create test file: done!
 ・ \\"<project>/fixtures/test-betterer-init-multiple/.betterer.ts\\" already exists, moving on...
 ✅ Update package.json: done!
 ・ \\"betterer\\" script already exists, moving on...
 ・ \\"@betterer/cli\\" dependency already exists, moving on...
+・ \\"typescript\\" dependency already exists, moving on...
 ",
 ]
 `;
diff --git a/test/cli/betterer-init.spec.ts b/test/cli/betterer-init.spec.ts
@@ -2,11 +2,11 @@ import { BettererPackageJSON, initΔ } from '@betterer/cli';
 
 import { createFixture } from '../fixture';
 
-const ARGV = ['node', './bin/betterer'];
+const ARGV = ['node', './bin/betterer', 'init'];
 
 describe('betterer cli', () => {
   it('should initialise betterer in a repo', async () => {
-    const { logs, paths, readFile, cleanup, resolve } = await createFixture(
+    const { cleanup, logs, paths, readFile, resolve } = await createFixture(
       'test-betterer-init',
       {
         'package.json': `
@@ -31,18 +31,19 @@ describe('betterer cli', () => {
 
     expect(packageJSON.scripts.betterer).toEqual('betterer');
     expect(packageJSON.devDependencies['@betterer/cli']).toBeDefined();
+    expect(packageJSON.devDependencies['typescript']).toBeDefined();
 
     const config = await readFile(configPath);
 
-    expect(config).toEqual('export default {\n  // Add tests here ☀️\n};');
+    expect(config).toEqual('export default {\n  // Add tests here ☀️\n};\n');
 
     expect(logs).toMatchSnapshot();
 
     await cleanup();
   });
 
   it('should work multiple times', async () => {
-    const { logs, paths, cleanup } = await createFixture(
+    const { cleanup, logs, paths } = await createFixture(
       'test-betterer-init-multiple',
       {
         'package.json': `
@@ -72,4 +73,41 @@ describe('betterer cli', () => {
 
     expect(logs).toMatchSnapshot();
   });
+
+  it('should initialise betterer in a repo with JS', async () => {
+    const { cleanup, logs, paths, readFile, resolve } = await createFixture(
+      'test-betterer-init-js',
+      {
+        'package.json': `
+      {
+        "name": "betterer-test-betterer-init-js",
+        "version": "0.0.1"
+      }
+      `
+      },
+      {
+        logFilters: [/🌟 Initialising Betterer/]
+      }
+    );
+
+    const configPath = `${paths.config}.js`;
+    const fixturePath = paths.cwd;
+    const packageJSONPath = resolve('./package.json');
+
+    await initΔ(fixturePath, [...ARGV, '--config', configPath]);
+
+    const packageJSON = JSON.parse(await readFile(packageJSONPath)) as BettererPackageJSON;
+
+    expect(packageJSON.scripts.betterer).toEqual('betterer');
+    expect(packageJSON.devDependencies['@betterer/cli']).toBeDefined();
+    expect(packageJSON.devDependencies['typescript']).not.toBeDefined();
+
+    const config = await readFile(configPath);
+
+    expect(config).toEqual('module.exports = {\n  // Add tests here ☀️\n};\n');
+
+    expect(logs).toMatchSnapshot();
+
+    await cleanup();
+  });
 });