feat(predicate): determine prettier existence based on config file

Author: travi

src/index.js

@@ -1 +1,2 @@
 export {default as scaffold} from './scaffolder.js';
+export {default as test} from './tester.js';

src/tester.js

@@ -0,0 +1,5 @@
+import {exists} from '@form8ion/config-file';
+
+export default function test({_}) {
+  return exists({name: 'prettier', _});
+}

src/tester.test.js

@@ -0,0 +1,25 @@
+import {exists} from '@form8ion/config-file';
+
+import {describe, it, vi, expect} from 'vitest';
+import {when} from 'vitest-when';
+import any from '@travi/any';
+
+import prettierIsPresent from './tester.js';
+
+vi.mock('@form8ion/config-file');
+
+describe('predicate', () => {
+  const dummyValueToSatisfySchema = any.simpleObject();
+
+  it('should return `true` when a config file is present', async () => {
+    when(exists).calledWith({name: 'prettier', _: dummyValueToSatisfySchema}).thenResolve(true);
+
+    expect(await prettierIsPresent({_: dummyValueToSatisfySchema})).toBe(true);
+  });
+
+  it('should return `false` when a config file is not present', async () => {
+    when(exists).calledWith({name: 'prettier', _: dummyValueToSatisfySchema}).thenResolve(false);
+
+    expect(await prettierIsPresent({_: dummyValueToSatisfySchema})).toBe(false);
+  });
+});

test/integration/features/form8ion.feature

@@ -0,0 +1,6 @@
+Feature: prettier as form8ion plugin
+
+  Scenario: plugin conventions
+    When the prettier plugin is compared to form8ion plugin conventions
+    Then the public interface is compatible with the plugin schema
+    And the output produced by the scaffolder is detectable by the predicate

test/integration/features/step_definitions/form8ion-steps.js

@@ -0,0 +1,19 @@
+import {validateOptions, optionsSchemas} from '@form8ion/core';
+
+import {Then, When} from '@cucumber/cucumber';
+import assert from 'node:assert';
+
+// eslint-disable-next-line import/no-extraneous-dependencies,import/no-unresolved
+import * as plugin from '@form8ion/prettier';
+
+When('the prettier plugin is compared to form8ion plugin conventions', async function () {
+  await plugin.scaffold({projectRoot: this.projectRoot});
+});
+
+Then('the public interface is compatible with the plugin schema', async function () {
+  validateOptions(optionsSchemas.form8ionPlugin, plugin);
+});
+
+Then('the output produced by the scaffolder is detectable by the predicate', async function () {
+  assert.equal(await plugin.test({projectRoot: this.projectRoot}), true);
+});