Add Number.parseFloat (#668)

Co-authored-by: Peli de Halleux <pelikhan@users.noreply.github.com>

packages/runtime/src/main.ts

@@ -273,6 +273,29 @@ describe("number", () => {
         checkNot(false)
         checkNot([NaN])
     })
+    test("parseFloat", () => {
+        const check = (v: unknown) => expect(Number.parseFloat(v)).toBe(3.14)
+        const checkNaN = (v: unknown) =>
+            expect(isNaN(Number.parseFloat(v))).toBe(isNaN(NaN))
+
+        const checkInfinity = (v: unknown) =>
+            expect(Number.parseFloat(v)).toBe(Infinity)
+
+        const checkMinusInfinity = (v: unknown) =>
+            expect(Number.parseFloat(v)).toBe(-Infinity)
+        check(3.14)
+        check("3.14")
+        check("  3.14  ")
+        check("314e-2")
+        check("0.0314E+2")
+        check("3.14some non-digit characters")
+        checkNaN("FF2")
+        checkNaN("NaN")
+        checkInfinity("1.7976931348623159e+308")
+        checkMinusInfinity("-1.7976931348623159e+308")
+        checkInfinity("Infinity")
+        checkMinusInfinity("-Infinity")
+    })
     test("isFinite", () => {
         const check = (v: unknown) => expect(Number.isFinite(v)).toBe(true)
         const checkNot = (v: unknown) => expect(Number.isFinite(v)).toBe(false)

packages/runtime/src/number.ts

@@ -21,7 +21,13 @@ export class Number {
         return isNaN(number as number)
     }
     /**
-     * Returns tru if the passed value is finite number, false otherwise.
+     * Returns floating point number parsed from the given string, or NaN when the first non-whitespace character cannot be converted to a number.
+     * @param string The value to parse, coerced to a string. Leading whitespace in this argument is ignored.
+     */
+    static parseFloat(string: unknown): number {
+        return parseFloat(string as string)
+    }
+    /** Returns tru if the passed value is finite number, false otherwise.
      * @param number A numeric value
      */
     static isFinite(number: unknown): boolean {