[analysis_server] Show library documentation when hovering over unnamed

library directives

Closes: #53476
Change-Id: I33a8e0ebd3ed7999eba71985fabb90c17444bde6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/380520
Commit-Queue: Konstantin Shcheglov <[email protected]>
Commit-Queue: Brian Wilkerson <[email protected]>
Reviewed-by: Konstantin Shcheglov <[email protected]>
Reviewed-by: Brian Wilkerson <[email protected]>

Author: halildurmus

pkg/analysis_server/lib/src/computer/computer_hover.dart

@@ -56,7 +56,8 @@ class DartUnitHoverComputer {
         node is VariableDeclaration ||
         node is VariablePattern ||
         node is PatternFieldName ||
-        node is DartPattern) {
+        node is DartPattern ||
+        (node is LibraryDirective && node.name2 == null)) {
       var range = _hoverRange(node, locationEntity);
       var hover = HoverInformation(range.offset, range.length);
       // element
@@ -196,6 +197,7 @@ class DartUnitHoverComputer {
       VariablePattern() => node.name,
       PatternFieldName() => node.name,
       WildcardPattern() => node.name,
+      LibraryDirective() => node.libraryKeyword,
       _ => null,
     };
   }

pkg/analysis_server/test/lsp/hover_test.dart

@@ -802,6 +802,22 @@ Type: `String?`
 
 *package:test/main.dart*
 
+---
+This is a string.''';
+    await assertStringContents(content, equals(expected));
+  }
+
+  Future<void> test_unnamed_library_directive() async {
+    var content = '''
+/// This is a string.
+[!lib^rary!];
+''';
+    var expected = '''
+```dart
+library package:test/main.dart
+```
+*package:test/main.dart*
+
 ---
 This is a string.''';
     await assertStringContents(content, equals(expected));