Use colon syntax instead of comma-arrow

Author: rattrayalex

src/parser/expression.js

@@ -239,15 +239,12 @@ pp.parseExprOps = function (noIn, refShorthandDefaultPos) {
 pp.parseExprOp = function(left, leftStartPos, leftStartLoc, minPrec, noIn) {
   // correct ASI failures.
   if (this.hasPlugin("lightscript") && this.isLineBreak()) {
-
     // if it's a newline followed by a unary +/-, bail so it can be parsed separately.
     if (this.match(tt.plusMin) && !this.isNextCharWhitespace()) {
       return left;
     }
-    // if it's a `|` in a match/case on a newline, assume it's for the "case"
-    // TODO: consider using indentation to be more precise about this
-    // TODO: just remove all bitwise operators so this isn't necessary.
-    if (this.match(tt.bitwiseOR) && this.state.inMatchCaseConsequent) {
+    // for match/case
+    if (this.match(tt.bitwiseOR)) {
       return left;
     }
   }
@@ -752,7 +749,7 @@ pp.parseExprAtom = function (refShorthandDefaultPos) {
       }
 
     case tt.dot:
-      if (this.hasPlugin("lightscript") && this.lookahead().type === tt.num) {
+      if (this.hasPlugin("lightscript") && this.lookahead().type === tt.num && !this.allowMatchCasePlaceholder()) {
         this.unexpected(null, "Decimal numbers must be prefixed with a `0` in LightScript (eg; `0.1`).");
       }
 

src/plugins/lightscript.js

@@ -573,7 +573,7 @@ pp.parseMatch = function () {
     }
 
     const matchCase = this.parseMatchCase();
-    if (matchCase.test && matchCase.test.type === "MatchElse") {
+    if (matchCase.test.type === "MatchElse") {
       hasUsedElse = true;
     }
     node.cases.push(matchCase);
@@ -586,17 +586,13 @@ pp.parseMatchCase = function () {
   const node = this.startNode();
 
   node.test = this.parseMatchCaseTest();
-  this.expect(tt.comma);
 
-  // parse arrow function expression. (TODO: consider allowing NamedArrowExpression)
-  const oldInMatchCaseConsequent = this.state.inMatchCaseConsequent;
-  this.state.inMatchCaseConsequent = true;
-  node.consequent = this.parseMaybeAssign();
-  this.state.inMatchCaseConsequent = oldInMatchCaseConsequent;
-  if (node.consequent.type !== "ArrowFunctionExpression") {
-    this.unexpected(node.consequent.start, tt.arrow);
+  if (this.eat(tt._with)) {
+    node.binding = this.parseBindingAtom();
   }
 
+  node.consequent = this.parseBlock(false);
+
   return this.finishNode(node, "MatchCase");
 };
 
@@ -634,8 +630,7 @@ pp.isSubscriptTokenForMatchCase = function (tokenType) {
     tokenType === tt.dot ||
     tokenType === tt.elvis ||
     tokenType === tt.tilde ||
-    tokenType === tt.bracketL ||
-    (tokenType === this.state.type && this.isNumberStartingWithDot())
+    tokenType === tt.bracketL
   );
 };
 

src/tokenizer/state.js

@@ -40,9 +40,7 @@ export default class State {
 
     // for lightscript
     this.indentLevel = 0;
-    this.inMatchCaseConsequent =
-      this.inMatchCaseTest =
-        false;
+    this.inMatchCaseTest = false;
 
     this.type = tt.eof;
     this.value = null;