fix(NODE-3021): fix a long standing bug in Decimal128.fromString() (#458)

Author: tzhuan

src/decimal128.ts

@@ -304,7 +304,7 @@ export class Decimal128 {
       lastDigit = nDigitsStored - 1;
       significantDigits = nDigits;
       if (significantDigits !== 1) {
-        while (representation[firstNonZero + significantDigits - 1] === '0') {
+        while (digits[firstNonZero + significantDigits - 1] === 0) {
           significantDigits = significantDigits - 1;
         }
       }

test/node/decimal128_tests.js

@@ -1210,6 +1210,11 @@ describe('Decimal128', function () {
     expect(new Decimal128('00').toString()).to.equal('0');
     expect(new Decimal128('0.5').toString()).to.equal('0.5');
     expect(new Decimal128('-0.5').toString()).to.equal('-0.5');
+    expect(new Decimal128('-0.0097').toString()).to.equal('-0.0097');
+    expect(new Decimal128('-0.0011').toString()).to.equal('-0.0011');
+    expect(new Decimal128('-0.00110').toString()).to.equal('-0.00110');
+    expect(new Decimal128('0.0011').toString()).to.equal('0.0011');
+    expect(new Decimal128('0.00110').toString()).to.equal('0.00110');
     expect(new Decimal128('-1e400').toString()).to.equal('-1E+400');
     done();
   });