Move removeIndex's result instead of copying (#1516)

jedav · baylesj · web-flow · commit fdb529bd0613 · 2024-09-09T19:53:56.000-07:00
Currently removeIndex copies the removed value into removed and then
destructs the original, which can cause significant performance overhead.

Co-authored-by: Jordan Bayles &lt;bayles.jordan@gmail.com&gt;
diff --git a/src/lib_json/json_value.cpp b/src/lib_json/json_value.cpp
@@ -1205,7 +1205,7 @@ bool Value::removeIndex(ArrayIndex index, Value* removed) {
     return false;
   }
   if (removed)
-    *removed = it->second;
+    *removed = std::move(it->second);
   ArrayIndex oldSize = size();
   // shift left all items left, into the place of the "removed"
   for (ArrayIndex i = index; i < (oldSize - 1); ++i) {

Original file line number	Diff line number	Diff line change
`@@ -1205,7 +1205,7 @@ bool Value::removeIndex(ArrayIndex index, Value* removed) {`
`1205`	`1205`	`return false;`
`1206`	`1206`	`}`
`1207`	`1207`	`if (removed)`
`1208`		`- *removed = it->second;`
	`1208`	`+ *removed = std::move(it->second);`
`1209`	`1209`	`ArrayIndex oldSize = size();`
`1210`	`1210`	`// shift left all items left, into the place of the "removed"`
`1211`	`1211`	`for (ArrayIndex i = index; i < (oldSize - 1); ++i) {`