fix dartdevc source maps incorrectly storing temporary variable locations
Change-Id: Ib31bdc1067275c718b581172308c3926e19f906e
Reviewed-on: https://dart-review.googlesource.com/66861
Reviewed-by: Alan Knight <alanknight@google.com>
diff --git a/pkg/dev_compiler/lib/src/compiler/js_names.dart b/pkg/dev_compiler/lib/src/compiler/js_names.dart
index 7de9cf9..8c02846 100644
--- a/pkg/dev_compiler/lib/src/compiler/js_names.dart
+++ b/pkg/dev_compiler/lib/src/compiler/js_names.dart
@@ -15,6 +15,23 @@
/// generation without needing global knowledge. See [TemporaryNamer].
// TODO(jmesserly): move into js_ast? add a boolean to Identifier?
class TemporaryId extends Identifier {
+ // TODO(jmesserly): by design, temporary identifier nodes are shared
+ // throughout the AST, so any source information we attach in one location
+ // be incorrect for another location (and overwrites previous data).
+ //
+ // If we want to track source information for temporary variables, we'll
+ // need to separate the identity of the variable from its Identifier.
+ //
+ // In practice that makes temporaries more difficult to use: they're no longer
+ // JS AST nodes, so `toIdentifier()` is required to put them in the JS AST.
+ // And anywhere we currently use type `Identifier` to hold Identifier or
+ // TemporaryId, those types would need to change to `Identifier Function()`.
+ //
+ // However we may need to fix this if we want hover to work well for things
+ // like library prefixes and field-initializing formals.
+ get sourceInformation => null;
+ set sourceInformation(Object obj) {}
+
TemporaryId(String name) : super(name);
}
