fixed issue with optional chaining conflating decimal numbers in a

ternary operator `true?.10:.20` would not work before
Contrast-Security-Inc · Oct 26, 2020 · db12621 · db12621
1 parent 46c64c7
commit db12621
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Showing 2 changed files with 3 additions and 2 deletions.
diff --git a/src/parser.ts b/src/parser.ts
@@ -1327,7 +1327,7 @@ export class Parser {
                 const quasi = this.parseTemplateLiteral();
                 expr = this.finalize(this.startNode(startToken), new Node.TaggedTemplateExpression(expr, quasi));
             } else if (this.match('?.')) {
-                this.nextToken();
+              this.nextToken();
                 if (this.match('(')) {
                     var asyncArrow = maybeAsync && (startToken.lineNumber === this.lookahead.lineNumber);
                     this.context.isBindingElement = false;

diff --git a/src/scanner.ts b/src/scanner.ts
@@ -608,7 +608,8 @@ export class Scanner {
                 break;
             case '?':
                 ++this.index;
-                if (this.source[this.index] === '.') {
+                // see https://github.com/tc39/proposal-optional-chaining#notes for why we have to check 2 lookaheads
+                if (this.source[this.index] === '.' && isNaN(Number(this.source[this.index +1]))) {
                     // optional chaining
                     this.index += 1;
                     str = '?.';