Add and arrayContentEquals

CHANGELOG.md

@@ -5,6 +5,7 @@
 - @cosmjs/cli: Import `encodeBech32Pubkey` and `decodeBech32Pubkey` by default.
 - @cosmjs/launchpad: Add ed25519 support to `encodeBech32Pubkey`.
 - @cosmjs/launchpad: Add `encodeAminoPubkey` and `decodeAminoPubkey`.
+- @cosmjs/utils: Add `arrayContentEquals`.
 
 ## 0.22.0 (2020-08-03)
 

packages/utils/src/array.spec.ts

@@ -0,0 +1,33 @@
+import { arrayContentEquals } from "./arrays";
+
+describe("array", () => {
+  describe("arrayContentEquals", () => {
+    it("can compare number arrays", () => {
+      expect(arrayContentEquals([1, 2, 3], [1, 2, 3])).toEqual(true);
+      expect(arrayContentEquals([1, 2, 3], [1, 2, 3, 4])).toEqual(false);
+      expect(arrayContentEquals([1, 2, 3], [3, 2, 1])).toEqual(false);
+    });
+
+    it("can compare string arrays", () => {
+      expect(arrayContentEquals(["a", "b"], ["a", "b"])).toEqual(true);
+      expect(arrayContentEquals(["a", "b"], ["a", "b", "c"])).toEqual(false);
+      expect(arrayContentEquals(["a", "b"], ["b", "a"])).toEqual(false);
+    });
+
+    it("can compare bool arrays", () => {
+      expect(arrayContentEquals([true, false], [true, false])).toEqual(true);
+      expect(arrayContentEquals([true, false], [true, false, true])).toEqual(false);
+      expect(arrayContentEquals([true, false], [false, true])).toEqual(false);
+    });
+
+    it("can compare different array types", () => {
+      expect(arrayContentEquals([1, 2, 3], new Uint8Array([1, 2, 3]))).toEqual(true);
+      expect(arrayContentEquals([1, 2, 3], new Uint8Array([3, 2, 1]))).toEqual(false);
+    });
+
+    it("works for empty arrays", () => {
+      expect(arrayContentEquals([], [])).toEqual(true);
+      expect(arrayContentEquals([], new Uint8Array([]))).toEqual(true);
+    });
+  });
+});

packages/utils/src/arrays.ts

@@ -0,0 +1,18 @@
+/**
+ * Compares the content of two arrays-like objects for equality.
+ *
+ * Equality is defined as having equal length and element values, where element equality means `===` returning `true`.
+ *
+ * This allows you to compare the content of a Buffer, Uint8Array or number[], ignoring the specific type.
+ * As a consequence, this returns different results than Jasmine's `toEqual`, which ensures elements have the same type.
+ */
+export function arrayContentEquals<T extends string | number | boolean>(
+  a: ArrayLike<T>,
+  b: ArrayLike<T>,
+): boolean {
+  if (a.length !== b.length) return false;
+  for (let i = 0; i < a.length; ++i) {
+    if (a[i] !== b[i]) return false;
+  }
+  return true;
+}

packages/utils/src/index.ts

@@ -1,3 +1,4 @@
+export { arrayContentEquals } from "./arrays";
 export { assert } from "./assert";
 export { sleep } from "./sleep";
 export { isNonNullObject, isUint8Array } from "./typechecks";

packages/utils/types/arrays.d.ts

@@ -0,0 +1,12 @@
+/**
+ * Compares the content of two arrays-like objects for equality.
+ *
+ * Equality is defined as having equal length and element values, where element equality means `===` returning `true`.
+ *
+ * This allows you to compare the content of a Buffer, Uint8Array or number[], ignoring the specific type.
+ * As a consequence, this returns different results than Jasmine's `toEqual`, which ensures elements have the same type.
+ */
+export declare function arrayContentEquals<T extends string | number | boolean>(
+  a: ArrayLike<T>,
+  b: ArrayLike<T>,
+): boolean;

packages/utils/types/index.d.ts

@@ -1,3 +1,4 @@
+export { arrayContentEquals } from "./arrays";
 export { assert } from "./assert";
 export { sleep } from "./sleep";
 export { isNonNullObject, isUint8Array } from "./typechecks";