feat(uuid): expose genTestUuid procedure

package.json

@@ -54,6 +54,7 @@
     "@trivago/prettier-plugin-sort-imports": "2.0.4",
     "@tsconfig/node-lts-strictest": "18.12.1",
     "@types/jest": "29.2.4",
+    "@types/uuid": "10.0.0",
     "@typescript-eslint/eslint-plugin": "5.46.1",
     "@typescript-eslint/parser": "5.46.1",
     "core-js": "3.26.1",
@@ -80,6 +81,7 @@
   },
   "license": "MIT",
   "dependencies": {
-    "@ehmpathy/error-fns": "1.3.1"
+    "@ehmpathy/error-fns": "1.3.1",
+    "uuid": "10.0.0"
   }
 }

src/genTestUuid.test.ts

@@ -0,0 +1,18 @@
+import { genTestUuid, isTestUuid } from './genTestUuid';
+
+describe('genTestUuid', () => {
+  it('should generate a uuid', () => {
+    const uuid = genTestUuid();
+    expect(uuid).toBeTruthy();
+  });
+  it('should generate a uuid that is namespaced for testing by whodis', () => {
+    const uuid = genTestUuid();
+    expect(uuid).toMatch(/^beef.*-.*-.*-.*-.*beef$/);
+    expect(isTestUuid(uuid)).toEqual(true);
+  });
+  it('should generate a uuid that is different every time', () => {
+    const uuid1 = genTestUuid();
+    const uuid2 = genTestUuid();
+    expect(uuid1).not.toEqual(uuid2);
+  });
+});

src/genTestUuid.ts

@@ -0,0 +1,17 @@
+import { v4 as uuid } from 'uuid';
+
+/**
+ * generates a random uuid namespaced for tests, pattern `beef****-****-****-****-********beef`
+ *
+ * usecase
+ * - produces a uuid that can be clearly identified as one produced for tests
+ */
+export const genTestUuid = (): string => {
+  return ['beef', uuid().slice(4, -4), 'beef'].join('');
+};
+
+/**
+ * decides whether a uuid is namespaced for tests
+ */
+export const isTestUuid = (userUuid: string): boolean =>
+  /^beef.{4}-.{4}-.{4}-.{4}-.{8}beef$/.test(userUuid);

src/index.ts

@@ -1,4 +1,5 @@
 export { given, when, then } from './givenWhenThen';
+export { genTestUuid } from './genTestUuid';
 
 // forward the getError method since it is almost always needed with tests
 export { getError } from '@ehmpathy/error-fns';