Fix inappropriate regexp tokenizing after anon class/function in for …

…spec Closes acornjs#982
jonyafek · Sep 29, 2020 · 9e308bb · 9e308bb
1 parent e232621
commit 9e308bb
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Showing 2 changed files with 8 additions and 1 deletion.
diff --git a/acorn/src/tokencontext.js b/acorn/src/tokencontext.js
@@ -110,7 +110,8 @@ tt.incDec.updateContext = function() {
 }
 
 tt._function.updateContext = tt._class.updateContext = function(prevType) {
-  if (prevType.beforeExpr && prevType !== tt.semi && prevType !== tt._else &&
+  if (prevType.beforeExpr && prevType !== tt._else &&
+      !(prevType === tt.semi && this.curContext() !== types.p_stat) &&
       !(prevType === tt._return && lineBreak.test(this.input.slice(this.lastTokEnd, this.start))) &&
       !((prevType === tt.colon || prevType === tt.braceL) && this.curContext() === types.b_stat))
     this.context.push(types.f_expr)

diff --git a/test/tests.js b/test/tests.js
@@ -29478,3 +29478,9 @@ test("'use strict'\n!=10; 05", {}, {ecmaVersion: 6})
 testFail("\"use strict\"\nfoo\n05", "Invalid number (3:0)", {ecmaVersion: 6})
 testFail("\"use strict\"\n;(foo)\n05", "Invalid number (3:0)", {ecmaVersion: 6})
 testFail("'use strict'\n!blah; 05", "Invalid number (2:7)", {ecmaVersion: 6})
+
+// Make sure a slash after an anonymous function/class in a for spec is treated as division
+test("for (; function () {} / 1;);", {}, {ecmaVersion: 6})
+test("for (; class {} / 1;);", {}, {ecmaVersion: 6})
+test("for (;; function () {} / 1);", {}, {ecmaVersion: 6})
+test("for (;; class {} / 1);", {}, {ecmaVersion: 6})