chore: add more meaningful error message for incorrect config names

src/index.ts

@@ -70,6 +70,25 @@ export default function createConfig({
  })
  }
 
+ // More meaningful error message for the user, in case they didn't know the correct config name.
+ for (const name of configNamesToExtend) {
+ if (!tseslint.configs[name]) {
+ const nameInCamelCase = name.replace(/-([a-z])/g, (_, letter) =>
+ letter.toUpperCase(),
+ )
+
+ // @ts-expect-error
+ if (tseslint.configs[nameInCamelCase]) {
+ throw new Error(
+ `The config name "${name}" is not supported in "extends". ` +
+ `Please use "${nameInCamelCase}" instead.`,
+ )
+ }
+
+ throw new Error(`Unknown config name in "extends": ${name}.`)
+ }
+ }
+
  const mayHaveJsxInSfc = supportedScriptLangs.jsx || supportedScriptLangs.tsx
  const needsTypeAwareLinting = configNamesToExtend.some(
  name =>

test/index.spec.ts

@@ -191,3 +191,14 @@ test('#87: should not error if the project root has an older version of espree i
  const { stdout } = await runLintAgainst('with-older-espree', FROM_FIXTURES)
  expect(stdout).toMatch(WHITESPACE_ONLY)
 })
+
+test('should guide user to use camelCase names in "extends"', async () => {
+ const eslintConfigPath = path.join(__dirname, '../examples/type-checked/eslint.config.js')
+ const { modify, restore } = setupFileMutations(eslintConfigPath)
+ modify((oldContents) => oldContents.replace('recommendedTypeChecked', 'recommended-type-checked'))
+ const { failed, stderr } = await runLintAgainst('type-checked')
+ restore()
+
+ expect(failed).toBe(true)
+ expect(stderr).contain('Please use "recommendedTypeChecked"')
+})