test: adds tests for pipe

test/pipe.test.ts

@@ -0,0 +1,70 @@
+import { pipe } from '~/pipe';
+
+describe(`sync`, () => {
+  test(`works w/ 1 function`, () => {
+    const fn = pipe((value: string) => value + 'bar');
+    expect(fn('foo')).toBe('foobar');
+  });
+  test(`works w/ a number of functions`, () => {
+    const fn = pipe(
+      (value: string) => value + 'bar',
+      (value) => ({ value }),
+      (value) => ({ value: value.value + 'baz' })
+    );
+
+    expect(fn('foo')).toEqual({ value: 'foobarbaz' });
+  });
+  test(`works w/ intermediary undefined values`, () => {
+    const fn = pipe(
+      (value: string) => value + 'bar',
+      undefined,
+      (value) => ({ value }),
+      undefined,
+      undefined,
+      (value) => ({ value: value.value + 'baz' }),
+      undefined
+    );
+
+    expect(fn('foo')).toEqual({ value: 'foobarbaz' });
+  });
+});
+
+describe(`async`, () => {
+  test(`returns a promise`, () => {
+    const fn = pipe.async((value: string) => value + 'bar');
+
+    expect(fn('foo')).toBeInstanceOf(Promise);
+  });
+  test(`works w/ 1 sync function`, async () => {
+    const fn = pipe.async((value: string) => value + 'bar');
+
+    await expect(fn('foo')).resolves.toBe('foobar');
+  });
+  test(`works w/ 1 async function`, async () => {
+    const fn = pipe.async(async (value: string) => value + 'bar');
+
+    await expect(fn('foo')).resolves.toBe('foobar');
+  });
+  test(`works w/ a number of functions`, async () => {
+    const fn = pipe.async(
+      async (value: string) => value + 'bar',
+      (value) => ({ value }),
+      async (value) => ({ value: value.value + 'baz' })
+    );
+
+    await expect(fn('foo')).resolves.toEqual({ value: 'foobarbaz' });
+  });
+  test(`works w/ intermediary undefined values`, async () => {
+    const fn = pipe.async(
+      async (value: string) => value + 'bar',
+      undefined,
+      (value) => ({ value }),
+      undefined,
+      undefined,
+      async (value) => ({ value: value.value + 'baz' }),
+      undefined
+    );
+
+    await expect(fn('foo')).resolves.toEqual({ value: 'foobarbaz' });
+  });
+});