wip(semantic-release): defined a predicate for determining if semantic-release is configured for the project

Author: travi

src/semantic-release/index.js

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

src/semantic-release/tester-test.js

@@ -0,0 +1,34 @@
+import {promises as fs} from 'fs';
+
+import sinon from 'sinon';
+import {assert} from 'chai';
+import any from '@travi/any';
+
+import determineIfSemanticReleaseIsConfigured from './tester';
+
+suite('semantic-release predicate', () => {
+  let sandbox;
+  const projectRoot = any.string();
+
+  setup(() => {
+    sandbox = sinon.createSandbox();
+
+    sandbox.stub(fs, 'readFile');
+  });
+
+  teardown(() => sandbox.restore());
+
+  test('that `true` is returned when semantic-release is configured for the project', async () => {
+    fs.readFile
+      .withArgs(`${projectRoot}/package.json`, 'utf-8')
+      .resolves(JSON.stringify({...any.simpleObject(), version: '0.0.0-semantically-released'}));
+
+    assert.isTrue(await determineIfSemanticReleaseIsConfigured({projectRoot}));
+  });
+
+  test('that `false` is returned when semantic-release is not configured for the current project', async () => {
+    fs.readFile.withArgs(`${projectRoot}/package.json`, 'utf-8').resolves(JSON.stringify(any.simpleObject()));
+
+    assert.isFalse(await determineIfSemanticReleaseIsConfigured({projectRoot}));
+  });
+});

src/semantic-release/tester.js

@@ -0,0 +1,7 @@
+import {promises as fs} from 'fs';
+
+export default async function ({projectRoot}) {
+  const {version} = JSON.parse(await fs.readFile(`${projectRoot}/package.json`, 'utf-8'));
+
+  return '0.0.0-semantically-released' === version;
+}