add clearification on remove duplicate code. may remove the comment later

AdvancedUno · AdvancedUno · commit ec7aa4e03154 · 2026-07-02T23:56:11.000-07:00
diff --git a/cpp/src/arrow/util/key_value_metadata.cc b/cpp/src/arrow/util/key_value_metadata.cc
@@ -122,6 +122,8 @@ Status KeyValueMetadata::DeleteMany(std::vector<int64_t> indices) {
                               "of size ",
                               size);
   }
+  // Remove duplicate indices, otherwise the shifting logic below would move entries 
+  // to incorrect (potentially negative) positions
   indices.erase(std::unique(indices.begin(), indices.end()), indices.end());
   indices.push_back(size);
 

Original file line number	Diff line number	Diff line change
`@@ -122,6 +122,8 @@ Status KeyValueMetadata::DeleteMany(std::vector<int64_t> indices) {`
`122`	`122`	`"of size ",`
`123`	`123`	`size);`
`124`	`124`	`}`
	`125`	`+ // Remove duplicate indices, otherwise the shifting logic below would move entries`
	`126`	`+ // to incorrect (potentially negative) positions`
`125`	`127`	`indices.erase(std::unique(indices.begin(), indices.end()), indices.end());`
`126`	`128`	`indices.push_back(size);`
`127`	`129`