fix corner case in collapse_vars (#5574)

fixes #5573

lib/compress.js

@@ -2593,7 +2593,8 @@ Compressor.prototype.compress = function(node) {
                         if (value instanceof AST_Array) return !all(node.elements, function(element, index) {
                             return !arg_may_throw(reject, element, value[index]);
                         });
-                        return value.is_string(compressor) && !all(node.elements, function(element) {
+                        if (!value.is_string(compressor)) return true;
+                        return !all(node.elements, function(element) {
                             return !arg_may_throw(reject, element);
                         });
                     }

test/compress/destructured.js

@@ -3817,3 +3817,30 @@ issue_5533_drop_fargs: {
     expect_stdout: "PASS"
     node_version: ">=6"
 }
+
+issue_5573: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var log = console.log;
+        var a = "FAIL";
+        (function([ { [log(a)]: b } ]) {
+            A = 42;
+        })((a = "PASS", [ {} ]));
+        log(a, A);
+    }
+    expect: {
+        var log = console.log;
+        var a = "FAIL";
+        (function([ { [log(a)]: b } ]) {
+            A = 42;
+        })((a = "PASS", [ {} ]));
+        log(a, A);
+    }
+    expect_stdout: [
+        "PASS",
+        "PASS 42",
+    ]
+    node_version: ">=6"
+}