Merge pull request #4 from kryptus36/main

fix bug in fromString, adjust & add tests

src/tsid.ts

@@ -355,8 +355,9 @@ export class TSID {
         if (value.length !== TSID_CHARS_LENGTH) {
           throw new Error(`Invalid TSID string: (len=${value.length} chars, but expected ${TSID_CHARS_LENGTH})`)
         }
+
         number = Array.from(value).reduce(
-          (acc, c, i) => acc + (BigInt(ALPHABET_VALUES[c.charCodeAt(0)]) << BigInt(60 - i * 5)),
+          (acc, c, i) => acc + (BigInt(ALPHABET.indexOf(c.toUpperCase())) << BigInt(5 * (TSID_CHARS_LENGTH - i - 1))),
           BigInt(0)
         )
         break

test/tsid.test.ts

@@ -90,11 +90,30 @@ describe('TSID Testing', () => {
   })
 
   test('TSID fromString should create a TSID with the correct number', () => {
-    const str = '0AWE5HZP3SKTK'
+    const str = '0FG9Y986E7Y6M'
     const tsid = TSID.fromString(str, 'S')
-    expect(tsid.number).toBe(18409564052552383455n)
+    expect(tsid.number).toBe(558796316535421140n)
   })
 
+  test('TSID generated with constructor should be equal to the one generated with fromString', () => {
+    const str = '0FG9Y986E7Y6M'
+    const tsid1 = TSID.fromString(str, 'S')
+    const tsid2 = new TSID(tsid1.number)
+    expect(tsid1.number).toEqual(tsid2.number)
+    expect(tsid1.toBytes()).toEqual(tsid2.toBytes())
+    expect(tsid1.toString()).toEqual(tsid2.toString())
+  });
+
+  test('Random TSID should be compatible across types', () => {
+    const tsid1 = getTsid()
+    const tsid2 = TSID.fromBytes(tsid1.toBytes())
+    const tsid3 = TSID.fromString(tsid1.toString(), 'S')
+    const tsid4 = new TSID(tsid1.number)
+    expect(tsid1.number).toEqual(tsid2.number)
+    expect(tsid1.number).toEqual(tsid3.number)
+    expect(tsid1.number).toEqual(tsid4.number)
+  });
+
   describe('Property-based Testing', () => {
     test('For any size TSID array, first item should small than the second one', () => {
       fc.assert(