[analysis_server] Add support for type inlay hints for dot shorthands

Fixes #61841

Change-Id: I0697c9a05639e723aec32e84b1680f72a2241d5c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/458300
Commit-Queue: Brian Wilkerson <[email protected]>
Reviewed-by: Brian Wilkerson <[email protected]>
Reviewed-by: Kallen Tu <[email protected]>

Author: DanTup

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

@@ -38,6 +38,20 @@ class DartInlayHintComputer {
        _lineInfo = result.lineInfo,
        _config = config ?? LspClientInlayHintsConfiguration(null);
 
+  /// Adds a type hint before [period] showing a label for the type [type].
+  void addDotShorthandTypePrefix(Token period, DartType? type) {
+    if (type == null) {
+      return;
+    }
+
+    _addTypePrefix(
+      period,
+      type,
+      _InlayHintKind.dotShorthandType,
+      paddingRight: false,
+    );
+  }
+
   /// Adds a parameter name hint before [nodeOrToken] showing a the name for
   /// [parameter].
   ///
@@ -80,15 +94,20 @@ class DartInlayHintComputer {
   ///
   /// Padding will be added between the hint and [entity] automatically.
   void addParameterTypePrefix(SyntacticEntity entity, DartType type) {
-    _addTypePrefix(entity, type, _InlayHintKind.parameterType);
+    _addTypePrefix(
+      entity,
+      type,
+      _InlayHintKind.parameterType,
+      paddingRight: true,
+    );
   }
 
   /// Adds a return type hint before [token] showing a label for the type
   /// [type].
   ///
   /// Padding will be added between the hint and [token] automatically.
   void addReturnTypePrefix(Token token, DartType type) {
-    _addTypePrefix(token, type, _InlayHintKind.returnType);
+    _addTypePrefix(token, type, _InlayHintKind.returnType, paddingRight: true);
   }
 
   /// Adds a type hint for [nodeOrToken] showing a label for type arguments
@@ -128,7 +147,12 @@ class DartInlayHintComputer {
   ///
   /// Padding will be added between the hint and [entity] automatically.
   void addVariableTypePrefix(SyntacticEntity entity, DartType type) {
-    _addTypePrefix(entity, type, _InlayHintKind.variableType);
+    _addTypePrefix(
+      entity,
+      type,
+      _InlayHintKind.variableType,
+      paddingRight: true,
+    );
   }
 
   List<InlayHint> compute() {
@@ -157,6 +181,7 @@ class DartInlayHintComputer {
   /// Record [hint] if the user configuration has [kind] enabled.
   void _addHint(InlayHint hint, _InlayHintKind kind) {
     var isEnabled = switch (kind) {
+      _InlayHintKind.dotShorthandType => _config.dotShorthandTypesEnabled,
       _InlayHintKind.parameterNameLiteral =>
         _config.parameterNamesMode != InlayHintsParameterNamesMode.none,
       _InlayHintKind.parameterNameNonLiteral =>
@@ -174,12 +199,15 @@ class DartInlayHintComputer {
 
   /// Adds a type hint before [nodeOrToken] showing a label for the type [type].
   ///
-  /// Padding will be added between the hint and [nodeOrToken] automatically.
+  /// If [paddingRight] is `true`, padding will be added to the right of the
+  /// type name automatically (which is desired except in the case where the
+  /// following character is a `.` such as a dot shorthand).
   void _addTypePrefix(
     SyntacticEntity nodeOrToken,
     DartType type,
-    _InlayHintKind inlayHintKind,
-  ) {
+    _InlayHintKind inlayHintKind, {
+    required bool paddingRight,
+  }) {
     var offset = nodeOrToken.offset;
     var position = toPosition(_lineInfo.getLocation(offset));
     var labelParts = <InlayHintLabelPart>[];
@@ -189,7 +217,7 @@ class DartInlayHintComputer {
         label: Either2<List<InlayHintLabelPart>, String>.t1(labelParts),
         position: position,
         kind: InlayHintKind.Type,
-        paddingRight: true,
+        paddingRight: paddingRight,
       ),
       inlayHintKind,
     );
@@ -356,6 +384,29 @@ class _DartInlayHintComputerVisitor extends GeneralizingAstVisitor<void> {
     }
   }
 
+  @override
+  void visitDotShorthandConstructorInvocation(
+    DotShorthandConstructorInvocation node,
+  ) {
+    super.visitDotShorthandConstructorInvocation(node);
+
+    _computer.addDotShorthandTypePrefix(node.period, node.staticType);
+  }
+
+  @override
+  void visitDotShorthandInvocation(DotShorthandInvocation node) {
+    super.visitDotShorthandInvocation(node);
+
+    _computer.addDotShorthandTypePrefix(node.period, node.staticType);
+  }
+
+  @override
+  void visitDotShorthandPropertyAccess(DotShorthandPropertyAccess node) {
+    super.visitDotShorthandPropertyAccess(node);
+
+    _computer.addDotShorthandTypePrefix(node.period, node.staticType);
+  }
+
   @override
   void visitFunctionDeclaration(FunctionDeclaration node) {
     super.visitFunctionDeclaration(node);
@@ -489,10 +540,11 @@ class _DartInlayHintComputerVisitor extends GeneralizingAstVisitor<void> {
 ///
 /// Each of these can be mapped into a configuration setting that controls it.
 enum _InlayHintKind {
+  dotShorthandType,
   parameterNameLiteral,
   parameterNameNonLiteral,
-  returnType,
   parameterType,
-  variableType,
+  returnType,
   typeArgument,
+  variableType,
 }

pkg/analysis_server/lib/src/lsp/client_configuration.dart

@@ -184,6 +184,7 @@ class LspClientConfiguration {
 /// "dart.inlayHints": false, // Disables all Inlay Hints
 ///
 /// "dart.inlayHints": {
+///   "dotShorthandTypes": { "enabled": true },
 ///   "parameterNames": { "enabled": "literal" },
 ///   "parameterTypes": { "enabled": true },
 ///   "returnTypes": { "enabled": false },
@@ -192,6 +193,7 @@ class LspClientConfiguration {
 /// }
 /// ```
 class LspClientInlayHintsConfiguration {
+  late bool _dotShorthandTypes;
   late InlayHintsParameterNamesMode _parameterNames;
   late bool _parameterTypes;
   late bool _returnTypes;
@@ -202,6 +204,7 @@ class LspClientInlayHintsConfiguration {
     var map = userPreference is Map<String, Object?> ? userPreference : null;
     var boolean = userPreference is bool ? userPreference : null;
 
+    _dotShorthandTypes = _getEnabled(map, 'dotShorthandTypes', boolean ?? true);
     _parameterNames = _getParameterNamesMode(
       map,
       boolean ?? true
@@ -214,6 +217,9 @@ class LspClientInlayHintsConfiguration {
     _variableTypes = _getEnabled(map, 'variableTypes', boolean ?? true);
   }
 
+  /// Whether dot shorthand type inlay hints are enabled.
+  bool get dotShorthandTypesEnabled => _dotShorthandTypes;
+
   /// Which kind of parameter names to show inlay hints for.
   InlayHintsParameterNamesMode get parameterNamesMode => _parameterNames;
 

pkg/analysis_server/test/lsp/client_configuration_test.dart

@@ -67,6 +67,35 @@ class ClientConfigurationTest with ResourceProviderMixin {
 /// for each kind of hint.
 @reflectiveTest
 class InlayHintsConfigurationTest {
+  void test_dotShorthandTypes_disabled() {
+    var options = [
+      LspClientInlayHintsConfiguration(false),
+      LspClientInlayHintsConfiguration({'dotShorthandTypes': false}),
+      LspClientInlayHintsConfiguration({
+        'dotShorthandTypes': {'enabled': false},
+      }),
+    ];
+
+    for (var option in options) {
+      expect(option.dotShorthandTypesEnabled, false);
+    }
+  }
+
+  void test_dotShorthandTypes_enabled() {
+    var options = [
+      LspClientInlayHintsConfiguration(null),
+      LspClientInlayHintsConfiguration(true),
+      LspClientInlayHintsConfiguration({'dotShorthandTypes': true}),
+      LspClientInlayHintsConfiguration({
+        'dotShorthandTypes': {'enabled': true},
+      }),
+    ];
+
+    for (var option in options) {
+      expect(option.dotShorthandTypesEnabled, true);
+    }
+  }
+
   void test_parameterNames_all() {
     var options = [
       LspClientInlayHintsConfiguration(null),

pkg/analysis_server/test/lsp/inlay_hint_test.dart

@@ -385,6 +385,44 @@ final a = 1;
     expect(hintsAfterChange, isNotEmpty);
   }
 
+  Future<void> test_dotShorthand_constructorInvocation() async {
+    var content = '''
+class A {
+  const A.named();
+}
+
+A newA() => .named();
+''';
+    var expected = '''
+class A {
+  const A.named();
+}
+
+A newA() => (Type:A).named();
+''';
+    await _expectHints(content, expected);
+  }
+
+  Future<void> test_dotShorthand_invocation() async {
+    var content = '''
+int a = .parse('1');
+''';
+    var expected = '''
+int a = (Type:int).parse((Parameter:source:) '1');
+''';
+    await _expectHints(content, expected);
+  }
+
+  Future<void> test_dotShorthand_propertyAccess() async {
+    var content = '''
+Duration zero() => .zero;
+''';
+    var expected = '''
+Duration zero() => (Type:Duration).zero;
+''';
+    await _expectHints(content, expected);
+  }
+
   Future<void> test_forElement() async {
     var content = '''
 void f() {

pkg/analysis_server/tool/lsp_spec/README.md

@@ -45,6 +45,7 @@ Client workspace settings are requested with `workspace/configuration` during in
 - `dart.documentation` (`none`, `summary`, `full`): The kind of dartdocs to include in requests that can return large numbers of results such as Code Completion. If not set, defaults to `full`.
 - `dart.includeDependenciesInWorkspaceSymbols` (`bool?`): Whether to include symbols from dependencies and Dart/Flutter SDKs in Workspace Symbol results. If not set, defaults to `true`.
 - `dart.inlayHints` (`bool?` | `Object?`): Whether to show Inlay Hints. When set to `true`, enables all inlay hints with default settings. When set to `false`, disables all inlay hints. Can also be an object to configure individual hint types as defined below. Defaults to `true`.
+  - `dotShorthandTypes` (`{ "enabled": bool }`): Whether to show Inlay Hints for dot shorthand types.
   - `parameterNames` (`{ "enabled": true | false | "none" | "literal" | "all" }`): Controls parameter name hints.
     - `"none"` or `false`: show no parameter name hints
 	- `"literal"`: show hints only for arguments with literal values