fix corner case in `collapse_vars` (#3139)

1 files changed, 4 insertions, 2 deletions

diff --git a/lib/compress.js b/lib/compress.js
index 5f35b98a..efc7c47f 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -1240,7 +1240,10 @@ merge(Compressor.prototype, {
             }
 
             function should_stop(node, parent) {
-                if (node instanceof AST_Assign) return node.operator != "=" && lhs.equivalent_to(node.left);
+                if (parent instanceof AST_For) return node !== parent.init;
+                if (node instanceof AST_Assign) {
+                    return node.operator != "=" && lhs.equivalent_to(node.left);
+                }
                 if (node instanceof AST_Call) {
                     return lhs instanceof AST_PropAccess && lhs.equivalent_to(node.expression);
                 }
@@ -1249,7 +1252,6 @@ merge(Compressor.prototype, {
                 if (node instanceof AST_LoopControl) return true;
                 if (node instanceof AST_Try) return true;
                 if (node instanceof AST_With) return true;
-                if (parent instanceof AST_For) return node !== parent.init;
                 if (replace_all) return false;
                 return node instanceof AST_SymbolRef && !node.is_declared(compressor);
             }