Assume limited precision when rounding

test/node/ol/math.test.js

@@ -1,12 +1,16 @@
 import expect from '../expect.js';
 import {
+  ceil,
   clamp,
   cosh,
+  floor,
   lerp,
   log2,
   modulo,
+  round,
   solveLinearSystem,
   toDegrees,
+  toFixed,
   toRadians,
 } from '../../../src/ol/math.js';
 
@@ -162,4 +166,82 @@ describe('ol/math.js', () => {
       expect(lerp(0.25, 0.75, 0.5)).to.be(0.5);
     });
   });
+
+  describe('toFixed', () => {
+    it('returns a number with a limited number of decimals', () => {
+      expect(toFixed(0.123456789, 3)).to.be(0.123);
+    });
+
+    it('rounds up', () => {
+      expect(toFixed(0.123456789, 4)).to.be(0.1235);
+    });
+
+    const cases = [
+      [1.23456789, 0],
+      [1.23456789, 1],
+      [1.23456789, 2],
+      [1.23456789, 3],
+      [1.23456789, 4],
+      [1.23456789, 5],
+      [1.23456789, 6],
+      [1.23456789, 7],
+      [1.23456789, 8],
+      [1.23456789, 9],
+      [1.23456789, 10],
+    ];
+    for (const c of cases) {
+      it(`provides numeric equivalent of (${c[0]}).toFixed(${c[1]})`, () => {
+        const string = c[0].toFixed(c[1]);
+        const expected = parseFloat(string);
+        const actual = toFixed(c[0], c[1]);
+        expect(actual).to.be(expected);
+      });
+    }
+  });
+
+  describe('round', () => {
+    const cases = [
+      [1.23, 2, 1],
+      [3.45, 1, 4],
+      [3.45, 2, 3],
+      [-3.45, 1, -3],
+      [-3.45, 2, -3],
+    ];
+
+    for (const c of cases) {
+      it(`works for round(${c[0]}, ${c[1]})`, () => {
+        expect(round(c[0], c[1])).to.be(c[2]);
+      });
+    }
+  });
+
+  describe('floor', () => {
+    const cases = [
+      [3.999, 4, 3],
+      [3.999, 2, 4],
+      [-3.01, 2, -4],
+      [-3.01, 1, -3],
+    ];
+
+    for (const c of cases) {
+      it(`works for floor(${c[0]}, ${c[1]})`, () => {
+        expect(floor(c[0], c[1])).to.be(c[2]);
+      });
+    }
+  });
+
+  describe('ceil', () => {
+    const cases = [
+      [4.001, 4, 5],
+      [4.001, 2, 4],
+      [-3.99, 3, -3],
+      [-3.99, 1, -4],
+    ];
+
+    for (const c of cases) {
+      it(`works for ceil(${c[0]}, ${c[1]})`, () => {
+        expect(ceil(c[0], c[1])).to.be(c[2]);
+      });
+    }
+  });
 });