fix(number): improve float generation for precisions of form 10^-n

src/modules/number/index.ts

@@ -150,8 +150,9 @@ export class NumberModule extends SimpleModuleBase {
         throw new FakerError(`Precision should be greater than 0.`);
       }
 
-      const factor = Number.isInteger(Math.log10(precision))
-        ? Math.pow(10, -Math.log10(precision)) //mathematically this is the same as 1/precision, however it helpfully gives integer values for all precisions of the form 10^-n
+      const logPrecision = Math.log10(precision);
+      const factor = Number.isInteger(logPrecision)
+        ? Math.pow(10, -logPrecision) //mathematically this is the same as 1/precision, however it helpfully gives integer values for all precisions of the form 10^-n
         : 1 / precision;
       const int = this.int({
         min: min * factor,

test/modules/number.spec.ts

@@ -275,25 +275,16 @@ describe('number', () => {
         expect(results).toEqual([0, 0.2, 0.4]);
       });
 
-      it('provides numbers with an exact precision', () => {
-        for (let i = 0; i < 100; i++) {
-          const actual = faker.number.float({
-            min: 0.5,
-            max: 0.99,
-            precision: 0.01,
-          });
-          expect(actual).toBe(Number(actual.toFixed(2)));
-        }
-      });
-
-      it('provides numbers with an exact precision of 0.00001', () => {
-        for (let i = 0; i < 100; i++) {
-          const actual = faker.number.float({
-            min: 0.5,
-            max: 0.99,
-            precision: 0.00001,
-          });
-          expect(actual).toBe(Number(actual.toFixed(5)));
+      it('provides numbers with an exact precision of 10^-x for x=1 to 18', () => {
+        for (let factor = 1; factor <= 18; factor++) {
+          for (let i = 0; i < 100; i++) {
+            const actual = faker.number.float({
+              min: 0.5,
+              max: 0.99,
+              precision: Math.pow(10, -factor),
+            });
+            expect(actual).toBe(Number(actual.toFixed(factor)));
+          }
         }
       });