LibJS: Add %TypedArray%.prototype.find

2025-07-27 05:17:35 +00:00 · 2021-06-18 03:57:53 +01:00 · 2021-06-18 03:57:53 +01:00 · 61a8c19556
commit 61a8c19556
parent 65ca2d98af
3 changed files with 124 additions and 0 deletions
--- a/Userland/Libraries/LibJS/Tests/builtins/TypedArray/TypedArray.prototype.find.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/TypedArray/TypedArray.prototype.find.js
@ -0,0 +1,108 @@
+const TYPED_ARRAYS = [
+    Uint8Array,
+    Uint16Array,
+    Uint32Array,
+    Int8Array,
+    Int16Array,
+    Int32Array,
+    Float32Array,
+    Float64Array,
+];
+
+const BIGINT_TYPED_ARRAYS = [BigUint64Array, BigInt64Array];
+
+test("length is 1", () => {
+    TYPED_ARRAYS.forEach(T => {
+        expect(T.prototype.find).toHaveLength(1);
+    });
+
+    BIGINT_TYPED_ARRAYS.forEach(T => {
+        expect(T.prototype.find).toHaveLength(1);
+    });
+});
+
+describe("errors", () => {
+    function errorTests(T) {
+        test(`requires at least one argument (${T.name})`, () => {
+            expect(() => {
+                new T().find();
+            }).toThrowWithMessage(
+                TypeError,
+                "TypedArray.prototype.find() requires at least one argument"
+            );
+        });
+
+        test(`callback must be a function (${T.name})`, () => {
+            expect(() => {
+                new T().find(undefined);
+            }).toThrowWithMessage(TypeError, "undefined is not a function");
+        });
+    }
+
+    TYPED_ARRAYS.forEach(T => errorTests(T));
+    BIGINT_TYPED_ARRAYS.forEach(T => errorTests(T));
+});
+
+describe("normal behaviour", () => {
+    test("basic functionality", () => {
+        TYPED_ARRAYS.forEach(T => {
+            const typedArray = new T([1, 2, 3]);
+
+            expect(typedArray.find(value => value === 1)).toBe(1);
+            expect(typedArray.find(value => value === 2)).toBe(2);
+            expect(typedArray.find(value => value === 3)).toBe(3);
+            expect(typedArray.find((value, index) => index === 1)).toBe(2);
+            expect(typedArray.find(value => value == "1")).toBe(1);
+            expect(typedArray.find(value => value === 10)).toBeUndefined();
+        });
+
+        BIGINT_TYPED_ARRAYS.forEach(T => {
+            const typedArray = new T([1n, 2n, 3n]);
+
+            expect(typedArray.find(value => value === 1n)).toBe(1n);
+            expect(typedArray.find(value => value === 2n)).toBe(2n);
+            expect(typedArray.find(value => value === 3n)).toBe(3n);
+            expect(typedArray.find((value, index) => index === 1)).toBe(2n);
+            expect(typedArray.find(value => value == 1)).toBe(1n);
+            expect(typedArray.find(value => value == "1")).toBe(1n);
+            expect(typedArray.find(value => value === 1)).toBeUndefined();
+        });
+    });
+
+    test("never calls callback with empty array", () => {
+        function emptyTest(T) {
+            var callbackCalled = 0;
+            expect(
+                new T().find(() => {
+                    callbackCalled++;
+                })
+            ).toBeUndefined();
+            expect(callbackCalled).toBe(0);
+        }
+
+        TYPED_ARRAYS.forEach(T => emptyTest(T));
+        BIGINT_TYPED_ARRAYS.forEach(T => emptyTest(T));
+    });
+
+    test("calls callback once for every item", () => {
+        TYPED_ARRAYS.forEach(T => {
+            var callbackCalled = 0;
+            expect(
+                new T([1, 2, 3]).find(() => {
+                    callbackCalled++;
+                })
+            ).toBeUndefined();
+            expect(callbackCalled).toBe(3);
+        });
+
+        BIGINT_TYPED_ARRAYS.forEach(T => {
+            var callbackCalled = 0;
+            expect(
+                new T([1n, 2n, 3n]).find(() => {
+                    callbackCalled++;
+                })
+            ).toBeUndefined();
+            expect(callbackCalled).toBe(3);
+        });
+    });
+});