✨ feat: Add copy function.

Author: make-github-pseudonymous-again

.commitlintrc.js renamed to .commitlintrc.cjs

@@ -66,6 +66,7 @@
     "@babel/register": "7.14.5",
     "@commitlint/cli": "13.1.0",
     "@js-library/commitlint-config": "0.0.4",
+    "@randomized/random": "^4.0.0",
     "ava": "3.15.0",
     "babel-plugin-transform-remove-console": "6.9.4",
     "babel-plugin-unassert": "3.1.0",

package.json

@@ -0,0 +1,16 @@
+/**
+ * Copy.
+ *
+ * @param {ArrayLike} a
+ * @param {number} ai
+ * @param {number} aj
+ * @param {{[x: number]: any}} b
+ * @param {number} bi
+ */
+const copy = (a, ai, aj, b, bi) => {
+	for (; ai < aj; ++ai, ++bi) {
+		b[bi] = a[ai];
+	}
+};
+
+export default copy;

src/copy.js

@@ -1,2 +1 @@
-const answer = 42;
-export default answer;
+export {default as copy} from './copy.js';

src/index.js

@@ -0,0 +1,69 @@
+import test from 'ava';
+
+import {randint} from '@randomized/random';
+
+import {copy} from '../../src/index.js';
+
+function one(Constructor) {
+	test(`copy (${Constructor})`, (t) => {
+		const n = 100;
+		const ai = 23;
+		const aj = 73;
+		const bi = 49;
+
+		const a = new Constructor(n);
+		const b = new Constructor(n);
+
+		const resetb = () => {
+			for (let i = 0; i < n; ++i) {
+				b[i] = 0;
+			}
+		};
+
+		for (let i = 0; i < n; ++i) {
+			a[i] = randint(1, 2 ** 31);
+		}
+
+		resetb();
+
+		for (let i = 0; i < n; ++i) {
+			t.is(b[i], 0, `b[${i}] === 0`);
+		}
+
+		copy(a, 0, n, b, 0);
+
+		for (let i = 0; i < n; ++i) {
+			t.deepEqual(b[i], a[i], `b[${i}] === a[${i}]`);
+		}
+
+		resetb();
+
+		copy(a, ai, aj, b, bi);
+
+		for (let i = 0; i < n; ++i) {
+			if (i < bi || i >= bi + aj - ai) {
+				t.is(b[i], 0, `b[${i}] === 0`);
+			} else {
+				const j = i - bi + ai;
+				t.deepEqual(b[i], a[j], `b[${i}] === a[${j}]`);
+			}
+		}
+	});
+}
+
+const arrays = [
+	Array,
+	Int8Array,
+	Int16Array,
+	Int32Array,
+	Uint8Array,
+	Uint16Array,
+	Uint32Array,
+	Uint8ClampedArray,
+	Float32Array,
+	Float64Array,
+];
+
+for (const Constructor of arrays) {
+	one(Constructor);
+}