expand regex to parse / grades

Author: Agilulfo

src/__tests__/scales/polish.ts

@@ -2,13 +2,19 @@
 import { Polish } from '../../scales'
 
 describe('Polish', () => {
-  describe('isPolish', () => {
+  describe('isType', () => {
     test('VI is a valid grade', () => {
       expect(Polish.isType('VI')).toBe(true)
     })
     test('asd is not a valid grade', () => {
       expect(Polish.isType('asd')).toBe(false)
     })
+    test('VI+/VI.1 is a valid slash grade', () => {
+      expect(Polish.isType('VI+/VI.1')).toBe(true)
+    })
+    test('VI+/VI.1+ is not a valid slash grade', () => {
+      expect(Polish.isType('VI+/VI.1')).toBe(false)
+    })
   })
   // describe('Get Score', () => {
   //   test('9a > 5c', () => {

src/scales/polish.ts

@@ -3,7 +3,7 @@ import routes from '../data/routes.json'
 import { Route } from '.'
 import { GradeBandTypes, routeScoreToBand } from '../GradeBands'
 
-const polishGradeRegex = /^((I{1,3})|(IV\+?)|(V[+,-]?)|(VI(.[1-9])?\+?))?$/i
+const polishGradeRegex = /^((?:I{1,3})|(?:IV[+]?)|(?:V[+,-]?)|(?:VI(?:\.[1-9])?[+]?)){1}(?:(\/)((?:I{1,3})|(?:IV[+]?)|(?:V[+,-]?)|(?:VI(?:\.[1-9])?[+]?)))?$/i
 const isPolish = (grade: string): RegExpMatchArray | null => grade.match(polishGradeRegex)
 
 const PolishScale: GradeScale = {