tests: add HexToDecimal.test.js (TheAlgorithms#1662)

Author: vil02

Conversions/HexToDecimal.js

@@ -1,4 +1,7 @@
 functionhexToInt(hexNum){
+if(!/^[0-9A-F]+$/.test(hexNum)){
+thrownewError('Invalid hex string.')
+}
 constnumArr=hexNum.split('')// converts number to array
 returnnumArr.map((item,index)=>{
 switch(item){
@@ -29,4 +32,4 @@ function hexToDecimal(hexNum){
 },0)
 }
 
-export{hexToInt,hexToDecimal}
+export{hexToDecimal}

Conversions/test/HexToDecimal.test.js

@@ -0,0 +1,24 @@
+import{hexToDecimal}from'../HexToDecimal'
+
+describe('Testing HexToDecimal',()=>{
+it.each([
+['0',0],
+['1',1],
+['A',10],
+['B',11],
+['C',12],
+['D',13],
+['E',14],
+['F',15],
+['10',16],
+['859',2137],
+['4D2',1234],
+['81323ABD92',554893491602]
+])('check with %s',(hexStr,expected)=>{
+expect(hexToDecimal(hexStr)).toBe(expected)
+})
+
+it.each(['a','-1','G',''])('throws for %s',(hexStr)=>{
+expect(()=>hexToDecimal(hexStr)).toThrowError()
+})
+})