Add number utility tests

test/numbers-test.ts

@@ -0,0 +1,163 @@
+/*
+Copyright 2021 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import {clamp, defaultNumber, percentageOf, percentageWithin, sum} from "../src/utils/numbers";
+
+describe('numbers', () => {
+    describe('defaultNumber', () => {
+        it('should use the default when the input is not a number', () => {
+            const def = 42;
+
+            let result = defaultNumber(null, def);
+            expect(result).toBe(def);
+
+            result = defaultNumber(undefined, def);
+            expect(result).toBe(def);
+
+            result = defaultNumber(Number.NaN, def);
+            expect(result).toBe(def);
+        });
+
+        it('should use the number when it is a number', () => {
+            const input = 24;
+            const def = 42;
+            const result = defaultNumber(input, def);
+            expect(result).toBe(input);
+        });
+    });
+
+    describe('clamp', () => {
+        it('should clamp high numbers', () => {
+            const input = 101;
+            const min = 0;
+            const max = 100;
+            const result = clamp(input, min, max);
+            expect(result).toBe(max);
+        });
+
+        it('should clamp low numbers', () => {
+            const input = -1;
+            const min = 0;
+            const max = 100;
+            const result = clamp(input, min, max);
+            expect(result).toBe(min);
+        });
+
+        it('should not clamp numbers in range', () => {
+            const input = 50;
+            const min = 0;
+            const max = 100;
+            const result = clamp(input, min, max);
+            expect(result).toBe(input);
+        });
+
+        it('should clamp floats', () => {
+            const min = -0.10;
+            const max = +0.10;
+
+            let result = clamp(-1.2, min, max);
+            expect(result).toBe(min);
+
+            result = clamp(1.2, min, max);
+            expect(result).toBe(max);
+
+            result = clamp(0.02, min, max);
+            expect(result).toBe(0.02);
+        });
+    });
+
+    describe('sum', () => {
+        it('should sum', () => { // duh
+            const result = sum(1, 2, 1, 4);
+            expect(result).toBe(8);
+        });
+    });
+
+    describe('percentageWithin', () => {
+        it('should work within 0-100', () => {
+            const result = percentageWithin(0.4, 0, 100);
+            expect(result).toBe(40);
+        });
+
+        it('should work within 0-100 when pct > 1', () => {
+            const result = percentageWithin(1.4, 0, 100);
+            expect(result).toBe(140);
+        });
+
+        it('should work within 0-100 when pct < 0', () => {
+            const result = percentageWithin(-1.4, 0, 100);
+            expect(result).toBe(-140);
+        });
+
+        it('should work with ranges other than 0-100', () => {
+            const result = percentageWithin(0.4, 10, 20);
+            expect(result).toBe(14);
+        });
+
+        it('should work with ranges other than 0-100 when pct > 1', () => {
+            const result = percentageWithin(1.4, 10, 20);
+            expect(result).toBe(24);
+        });
+
+        it('should work with ranges other than 0-100 when pct < 0', () => {
+            const result = percentageWithin(-1.4, 10, 20);
+            expect(result).toBe(-4);
+        });
+
+        it('should work with floats', () => {
+            const result = percentageWithin(0.4, 10.2, 20.4);
+            expect(result).toBe(14.28);
+        });
+    });
+
+    // These are the inverse of percentageWithin
+    describe('percentageOf', () => {
+        it('should work within 0-100', () => {
+            const result = percentageOf(40, 0, 100);
+            expect(result).toBe(0.4);
+        });
+
+        it('should work within 0-100 when val > 100', () => {
+            const result = percentageOf(140, 0, 100);
+            expect(result).toBe(1.40);
+        });
+
+        it('should work within 0-100 when val < 0', () => {
+            const result = percentageOf(-140, 0, 100);
+            expect(result).toBe(-1.40);
+        });
+
+        it('should work with ranges other than 0-100', () => {
+            const result = percentageOf(14, 10, 20);
+            expect(result).toBe(0.4);
+        });
+
+        it('should work with ranges other than 0-100 when val > 100', () => {
+            const result = percentageOf(24, 10, 20);
+            expect(result).toBe(1.4);
+        });
+
+        it('should work with ranges other than 0-100 when val < 0', () => {
+            const result = percentageOf(-4, 10, 20);
+            expect(result).toBe(-1.4);
+        });
+
+        it('should work with floats', () => {
+            const result = percentageOf(14.28, 10.2, 20.4);
+            expect(result).toBe(0.4);
+        });
+    });
+});