Enforce with before destructuring in match case

Author: rattrayalex

src/plugins/lightscript.js

@@ -638,28 +638,25 @@ pp.parseMatchCaseTest = function (node) {
     const elseNode = this.startNode();
     this.next();
     node.test = this.finishNode(elseNode, "MatchElse");
-  } else if (this.match(tt.braceL) || this.match(tt.bracketL)) {
-    // disambiguate `| { a, b }:` from `| { a, b }~someFn():`
-    const bindingOrTest = this.parseExprOps(false, { start: 0 });
-    try {
-      node.binding = this.toAssignable(bindingOrTest.__clone(), true, "match test");
-      node.test = null;
-    } catch (_err) {
-      node.test = bindingOrTest;
-    }
+  } else if (this.eat(tt._with)) {
+    this.parseMatchCaseBinding(node);
   } else {
     node.test = this.parseExprOps();
   }
 
   if (this.eat(tt._with)) {
-    if (node.binding) this.unexpected(this.state.lastTokStart, "Cannot destructure twice.");
-    if (!(this.match(tt.braceL) || this.match(tt.bracketL))) this.unexpected();
-    node.binding = this.parseBindingAtom();
+    this.parseMatchCaseBinding(node);
   }
 
   this.state.inMatchCaseTest = false;
 };
 
+pp.parseMatchCaseBinding = function (node) {
+  if (node.binding) this.unexpected(this.state.lastTokStart, "Cannot destructure twice.");
+  if (!(this.match(tt.braceL) || this.match(tt.bracketL))) this.unexpected();
+  node.binding = this.parseBindingAtom();
+};
+
 
 export default function (instance) {
 

test/fixtures/lightscript/match/destructuring-arr/actual.js

@@ -1,9 +1,8 @@
 match x:
-  // | [ a, b ] and a > 1: a + b
-  | [ a, b ]: a - b
-  | [ a, b = 2 ]: a + b - 2
-  | [ a, ...b ]: b.concat(a)
-  | [
+  | with [ a, b ]: a - b
+  | with [ a, b = 2 ]: a + b - 2
+  | with [ a, ...b ]: b.concat(a)
+  | with [
       [
         b
         d = 'e'
@@ -12,3 +11,8 @@ match x:
       ...j
   ]:
     [b, d, g, ...j].join('')
+  | foo with [ a, b ]: a - b
+  | foo with [ a, b = 2 ]: a + b - 2
+  | foo with [ a, ...b ]: b.concat(a)
+  | foo with [[b, d = 'e'], [g,,h], ...j ]:
+    [b, d, g, ...j].join('')