From 39e08a5e59f626ab713602bce8b645eeec2b94cf Mon Sep 17 00:00:00 2001
From: Craig Weber <crgwbr@gmail.com>
Date: Tue, 3 Sep 2024 15:11:07 -0400
Subject: [PATCH] feat: add _.compact replacement (#35)

---
 src/index.ts                |  1 +
 src/utils/compact.ts        | 14 ++++++++++++++
 tests/utils/compact.test.ts | 29 +++++++++++++++++++++++++++++
 3 files changed, 44 insertions(+)
 create mode 100644 src/utils/compact.ts
 create mode 100644 tests/utils/compact.test.ts

diff --git a/src/index.ts b/src/index.ts
index 48129d5..256711c 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -29,6 +29,7 @@ export * from './utils/is-null';
 export * from './utils/is-not-null-or-undefined';
 
 export * from './utils/chunk';
+export * from './utils/compact';
 export * from './utils/flatten';
 export * from './utils/pick';
 export * from './utils/pluck';
diff --git a/src/utils/compact.ts b/src/utils/compact.ts
new file mode 100644
index 0000000..4ed3936
--- /dev/null
+++ b/src/utils/compact.ts
@@ -0,0 +1,14 @@
+type FalsyVals = '' | 0 | false | null | undefined;
+
+function notFalsy<T>(value: T | FalsyVals): value is T {
+   return value !== ''
+      && value !== 0
+      && value !== false
+      && value !== null
+      && value !== undefined
+      && !(typeof value === 'number' && isNaN(value));
+}
+
+export function compact<T>(arr: (T | FalsyVals)[]): T[] {
+   return arr.filter(notFalsy);
+}
diff --git a/tests/utils/compact.test.ts b/tests/utils/compact.test.ts
new file mode 100644
index 0000000..f286512
--- /dev/null
+++ b/tests/utils/compact.test.ts
@@ -0,0 +1,29 @@
+import { expect } from 'chai';
+import { compact } from '../../src';
+
+describe('compact', () => {
+
+   it('compact arrays', () => {
+      const arrA: (string | number | boolean | null | undefined)[] = [
+         'foo',
+         0,
+         '',
+         true,
+         false,
+         null,
+         'hello',
+         undefined,
+         42,
+         NaN,
+      ];
+
+      const arrB: (string | number | boolean)[] = compact(arrA);
+
+      expect(arrB).to.eql([
+         'foo',
+         true,
+         'hello',
+         42,
+      ]);
+   });
+});