Prevent inlining variables into optional chains. Closes #1198

terser · Feb 12, 2023 · 12b7709 · 12b7709
1 parent 6268e5f
commit 12b7709
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Showing 2 changed files with 46 additions and 1 deletion.
diff --git a/lib/compress/tighten-body.js b/lib/compress/tighten-body.js
@@ -281,6 +281,9 @@ export function tighten_body(statements, compressor) {
                     && (node.logical || node.operator != "=" && lhs.equivalent_to(node.left))
                 || node instanceof AST_Await
                 || node instanceof AST_Call && lhs instanceof AST_PropAccess && lhs.equivalent_to(node.expression)
+                ||
+                    (node instanceof AST_Call || node instanceof AST_PropAccess)
+                    && node.optional
                 || node instanceof AST_Debugger
                 || node instanceof AST_Destructuring
                 || node instanceof AST_Expansion
@@ -454,7 +457,11 @@ export function tighten_body(statements, compressor) {
                 var hit = funarg;
                 var abort = false, replaced = 0, can_replace = !args || !hit;
                 if (!can_replace) {
-                    for (var j = compressor.self().argnames.lastIndexOf(candidate.name) + 1; !abort && j < args.length; j++) {
+                    for (
+                        let j = compressor.self().argnames.lastIndexOf(candidate.name) + 1;
+                        !abort && j < args.length;
+                        j++
+                    ) {
                         args[j].transform(scanner);
                     }
                     can_replace = true;

diff --git a/test/compress/collapse_vars.js b/test/compress/collapse_vars.js
@@ -6073,6 +6073,44 @@ do_not_place_chain_on_lhs_2: {
     }
 }
 
+optional_chain_call_argument_side_effect: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        ((this_is_null) => {
+            const results = console.log("PASS");
+            this_is_null?.(results);
+        })(id(null));
+    }
+    expect: {
+        ((this_is_null) => {
+            const results = console.log("PASS");
+            this_is_null?.(results);
+        })(id(null));
+    }
+    expect_stdout: "PASS"
+}
+
+optional_chain_call_prop_side_effect: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        ((this_is_null) => {
+            const results = console.log("PASS");
+            this_is_null?.[results];
+        })(id(null));
+    }
+    expect: {
+        ((this_is_null) => {
+            const results = console.log("PASS");
+            this_is_null?.[results];
+        })(id(null));
+    }
+    expect_stdout: "PASS"
+}
+
 shadowed_variable: {
     options = {
         pure_getters: true,