Ensure LSP uses actual signature help trigger characters

src/EditorFeatures/Core.Wpf/SignatureHelp/Controller.Session_ComputeModel.cs

@@ -75,7 +75,7 @@ private async Task<Model> ComputeModelInBackgroundAsync(
                         }
 
                         if (triggerInfo.TriggerCharacter.HasValue &&
-                            !currentModel.Provider.IsRetriggerCharacter(triggerInfo.TriggerCharacter.Value))
+                            !currentModel.Provider.RetriggerCharacters.Contains(triggerInfo.TriggerCharacter.Value))
                         {
                             return currentModel;
                         }

src/EditorFeatures/Core.Wpf/SignatureHelp/Controller_TypeChar.cs

@@ -100,7 +100,7 @@ void IChainedCommandHandler<TypeCharCommandArgs>.ExecuteCommand(TypeCharCommandA
         else
         {
             var computed = false;
-            if (allProviders.Any(static (p, args) => p.IsRetriggerCharacter(args.TypedChar), args))
+            if (allProviders.Any(static (p, args) => p.RetriggerCharacters.Contains(args.TypedChar), args))
             {
                 // The user typed a character that might close the scope of the current model.
                 // In this case, we should requery all providers.
@@ -138,7 +138,7 @@ void IChainedCommandHandler<TypeCharCommandArgs>.ExecuteCommand(TypeCharCommandA
         using var unmatchedProvidersDisposer = ArrayBuilder<ISignatureHelpProvider>.GetInstance(out var unmatchedProviders);
         foreach (var provider in providers)
         {
-            if (provider.IsTriggerCharacter(ch))
+            if (provider.TriggerCharacters.Contains(ch))
             {
                 matchedProviders.Add(provider);
             }

src/EditorFeatures/Test2/IntelliSense/SignatureHelpControllerTests.vb

@@ -2,6 +2,7 @@
 ' The .NET Foundation licenses this file to you under the MIT license.
 ' See the LICENSE file in the project root for more information.
 
+Imports System.Collections.Immutable
 Imports System.Runtime.CompilerServices
 Imports System.Threading
 Imports Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense
@@ -60,8 +61,8 @@ Namespace Microsoft.CodeAnalysis.Editor.UnitTests.IntelliSense
 
             ' Create a provider that will return an empty state when queried the second time
             Dim slowProvider = New Mock(Of ISignatureHelpProvider)(MockBehavior.Strict)
-            slowProvider.Setup(Function(p) p.IsTriggerCharacter(" "c)).Returns(True)
-            slowProvider.Setup(Function(p) p.IsRetriggerCharacter(" "c)).Returns(True)
+            slowProvider.Setup(Function(p) p.TriggerCharacters).Returns(ImmutableArray.Create(Of Char)(" "c))
+            slowProvider.Setup(Function(p) p.RetriggerCharacters).Returns(ImmutableArray.Create(Of Char)(" "c))
             slowProvider.Setup(Function(p) p.GetItemsAsync(It.IsAny(Of Document), It.IsAny(Of Integer), It.IsAny(Of SignatureHelpTriggerInfo), options, It.IsAny(Of CancellationToken))) _
                 .Returns(Task.FromResult(New SignatureHelpItems(CreateItems(2), TextSpan.FromBounds(0, 0), selectedItem:=0, semanticParameterIndex:=0, syntacticArgumentCount:=0, argumentName:=Nothing)))
             Dim controller = Await CreateController(CreateWorkspace(), provider:=slowProvider.Object, waitForPresentation:=True)
@@ -214,13 +215,17 @@ Namespace Microsoft.CodeAnalysis.Editor.UnitTests.IntelliSense
                                        Nothing))
             End Function
 
-            Public Function IsTriggerCharacter(ch As Char) As Boolean Implements ISignatureHelpProvider.IsTriggerCharacter
-                Return ch = "("c
-            End Function
-
-            Public Function IsRetriggerCharacter(ch As Char) As Boolean Implements ISignatureHelpProvider.IsRetriggerCharacter
-                Return ch = ")"c
-            End Function
+            Public ReadOnly Property TriggerCharacters As ImmutableArray(Of Char) Implements ISignatureHelpProvider.TriggerCharacters
+                Get
+                    Return ImmutableArray.Create("("c)
+                End Get
+            End Property
+
+            Public ReadOnly Property RetriggerCharacters As ImmutableArray(Of Char) Implements ISignatureHelpProvider.RetriggerCharacters
+                Get
+                    Return ImmutableArray.Create(")"c)
+                End Get
+            End Property
         End Class
 
         Private Shared Function CreateMockTextView(buffer As ITextBuffer) As Mock(Of ITextView)

src/EditorFeatures/TestUtilities/SignatureHelp/AbstractSignatureHelpProviderTests.cs

@@ -131,12 +131,12 @@ protected void VerifyTriggerCharacters(char[] expectedTriggerCharacters, char[]
 
         foreach (var expectedTriggerCharacter in expectedTriggerCharacters)
         {
-            Assert.True(signatureHelpProvider.IsTriggerCharacter(expectedTriggerCharacter), "Expected '" + expectedTriggerCharacter + "' to be a trigger character");
+            Assert.True(signatureHelpProvider.TriggerCharacters.Contains(expectedTriggerCharacter), "Expected '" + expectedTriggerCharacter + "' to be a trigger character");
         }
 
         foreach (var unexpectedTriggerCharacter in unexpectedTriggerCharacters)
         {
-            Assert.False(signatureHelpProvider.IsTriggerCharacter(unexpectedTriggerCharacter), "Expected '" + unexpectedTriggerCharacter + "' to NOT be a trigger character");
+            Assert.False(signatureHelpProvider.TriggerCharacters.Contains(unexpectedTriggerCharacter), "Expected '" + unexpectedTriggerCharacter + "' to NOT be a trigger character");
         }
     }
 
@@ -389,7 +389,7 @@ private async Task TestSignatureHelpWorkerSharedAsync(
                 SignatureHelpTriggerReason.TypeCharCommand,
                 code.ElementAt(cursorPosition - 1));
 
-            if (!signatureHelpProvider.IsTriggerCharacter(triggerInfo.TriggerCharacter.Value))
+            if (!signatureHelpProvider.TriggerCharacters.Contains(triggerInfo.TriggerCharacter.Value))
             {
                 return;
             }

src/Features/CSharp/Portable/SignatureHelp/AttributeSignatureHelpProvider.cs

@@ -4,6 +4,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Collections.Immutable;
 using System.Composition;
 using System.Diagnostics.CodeAnalysis;
 using System.Linq;
@@ -31,11 +32,9 @@ public AttributeSignatureHelpProvider()
     {
     }
 
-    public override bool IsTriggerCharacter(char ch)
-        => ch is '(' or ',';
+    public override ImmutableArray<char> TriggerCharacters => ['(', ','];
 
-    public override bool IsRetriggerCharacter(char ch)
-        => ch == ')';
+    public override ImmutableArray<char> RetriggerCharacters => [')'];
 
     private bool TryGetAttributeExpression(
         SyntaxNode root,
@@ -58,7 +57,7 @@ private bool IsTriggerToken(SyntaxToken token)
     {
         return !token.IsKind(SyntaxKind.None) &&
             token.ValueText.Length == 1 &&
-            IsTriggerCharacter(token.ValueText[0]) &&
+            TriggerCharacters.Contains(token.ValueText[0]) &&
             token.Parent is AttributeArgumentListSyntax &&
             token.Parent.Parent is AttributeSyntax;
     }

src/Features/CSharp/Portable/SignatureHelp/ConstructorInitializerSignatureHelpProvider.cs

@@ -4,6 +4,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Collections.Immutable;
 using System.Composition;
 using System.Linq;
 using System.Threading;
@@ -29,11 +30,9 @@ public ConstructorInitializerSignatureHelpProvider()
     {
     }
 
-    public override bool IsTriggerCharacter(char ch)
-        => ch is '(' or ',';
+    public override ImmutableArray<char> TriggerCharacters => ['(', ','];
 
-    public override bool IsRetriggerCharacter(char ch)
-        => ch == ')';
+    public override ImmutableArray<char> RetriggerCharacters => [')'];
 
     private async Task<ConstructorInitializerSyntax?> TryGetConstructorInitializerAsync(
         Document document,
@@ -57,7 +56,7 @@ public override bool IsRetriggerCharacter(char ch)
     }
 
     private bool IsTriggerToken(SyntaxToken token)
-        => SignatureHelpUtilities.IsTriggerParenOrComma<ConstructorInitializerSyntax>(token, IsTriggerCharacter);
+        => SignatureHelpUtilities.IsTriggerParenOrComma<ConstructorInitializerSyntax>(token, TriggerCharacters);
 
     private static bool IsArgumentListToken(ConstructorInitializerSyntax expression, SyntaxToken token)
     {

src/Features/CSharp/Portable/SignatureHelp/ElementAccessExpressionSignatureHelpProvider.cs

@@ -28,20 +28,17 @@ namespace Microsoft.CodeAnalysis.CSharp.SignatureHelp;
 [ExportSignatureHelpProvider("ElementAccessExpressionSignatureHelpProvider", LanguageNames.CSharp), Shared]
 internal sealed class ElementAccessExpressionSignatureHelpProvider : AbstractCSharpSignatureHelpProvider
 {
+    private static readonly ImmutableArray<char> s_triggerCharacters = ['[', ','];
+
     [ImportingConstructor]
     [Obsolete(MefConstruction.ImportingConstructorMessage, error: true)]
     public ElementAccessExpressionSignatureHelpProvider()
     {
     }
 
-    public override bool IsTriggerCharacter(char ch)
-        => IsTriggerCharacterInternal(ch);
-
-    private static bool IsTriggerCharacterInternal(char ch)
-        => ch is '[' or ',';
+    public override ImmutableArray<char> TriggerCharacters => s_triggerCharacters;
 
-    public override bool IsRetriggerCharacter(char ch)
-        => ch == ']';
+    public override ImmutableArray<char> RetriggerCharacters => [']'];
 
     private static bool TryGetElementAccessExpression(SyntaxNode root, int position, ISyntaxFactsService syntaxFacts, SignatureHelpTriggerReason triggerReason, CancellationToken cancellationToken, [NotNullWhen(true)] out ExpressionSyntax? identifier, out SyntaxToken openBrace)
     {
@@ -281,7 +278,7 @@ internal static bool IsTriggerToken(SyntaxToken token)
         {
             return !token.IsKind(SyntaxKind.None) &&
                 token.ValueText.Length == 1 &&
-                IsTriggerCharacterInternal(token.ValueText[0]) &&
+                s_triggerCharacters.Contains(token.ValueText[0]) &&
                 token.Parent is BracketedArgumentListSyntax &&
                 token.Parent.Parent is ElementAccessExpressionSyntax;
         }
@@ -330,7 +327,7 @@ internal static bool IsTriggerToken(SyntaxToken token)
         {
             return !token.IsKind(SyntaxKind.None) &&
                 token.ValueText.Length == 1 &&
-                IsTriggerCharacterInternal(token.ValueText[0]) &&
+                s_triggerCharacters.Contains(token.ValueText[0]) &&
                 token.Parent is ArrayRankSpecifierSyntax;
         }
 
@@ -365,7 +362,7 @@ internal static bool IsTriggerToken(SyntaxToken token)
         {
             return !token.IsKind(SyntaxKind.None) &&
                 token.ValueText.Length == 1 &&
-                IsTriggerCharacterInternal(token.ValueText[0]) &&
+                s_triggerCharacters.Contains(token.ValueText[0]) &&
                 token.Parent is BracketedArgumentListSyntax &&
                 token.Parent.Parent is ElementBindingExpressionSyntax &&
                 token.Parent.Parent.Parent is ConditionalAccessExpressionSyntax;

src/Features/CSharp/Portable/SignatureHelp/GenericNameSignatureHelpProvider.cs

@@ -4,6 +4,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Collections.Immutable;
 using System.Composition;
 using System.Linq;
 using System.Threading;
@@ -31,11 +32,9 @@ public GenericNameSignatureHelpProvider()
     {
     }
 
-    public override bool IsTriggerCharacter(char ch)
-        => ch is '<' or ',';
+    public override ImmutableArray<char> TriggerCharacters => ['<', ','];
 
-    public override bool IsRetriggerCharacter(char ch)
-        => ch == '>';
+    public override ImmutableArray<char> RetriggerCharacters => ['>'];
 
     protected virtual bool TryGetGenericIdentifier(
         SyntaxNode root, int position,
@@ -62,7 +61,7 @@ private bool IsTriggerToken(SyntaxToken token)
     {
         return !token.IsKind(SyntaxKind.None) &&
             token.ValueText.Length == 1 &&
-            IsTriggerCharacter(token.ValueText[0]) &&
+            TriggerCharacters.Contains(token.ValueText[0]) &&
             token.Parent is TypeArgumentListSyntax &&
             token.Parent.Parent is GenericNameSyntax;
     }

src/Features/CSharp/Portable/SignatureHelp/InitializerExpressionSignatureHelpProvider.cs

@@ -3,6 +3,7 @@
 // See the LICENSE file in the project root for more information.
 
 using System;
+using System.Collections.Immutable;
 using System.Composition;
 using System.Diagnostics.CodeAnalysis;
 using System.Linq;
@@ -26,11 +27,9 @@ public InitializerExpressionSignatureHelpProvider()
     {
     }
 
-    public override bool IsTriggerCharacter(char ch)
-        => ch is '{' or ',';
+    public override ImmutableArray<char> TriggerCharacters => ['{', ','];
 
-    public override bool IsRetriggerCharacter(char ch)
-        => ch == '}';
+    public override ImmutableArray<char> RetriggerCharacters => ['}'];
 
     private bool TryGetInitializerExpression(
         SyntaxNode root,
@@ -47,7 +46,7 @@ private bool TryGetInitializerExpression(
     private bool IsTriggerToken(SyntaxToken token)
         => !token.IsKind(SyntaxKind.None) &&
            token.ValueText.Length == 1 &&
-           IsTriggerCharacter(token.ValueText[0]) &&
+           TriggerCharacters.Contains(token.ValueText[0]) &&
            token.Parent is InitializerExpressionSyntax;
 
     private static bool IsInitializerExpressionToken(InitializerExpressionSyntax expression, SyntaxToken token)

src/Features/CSharp/Portable/SignatureHelp/InvocationExpressionSignatureHelpProvider.cs

@@ -30,11 +30,9 @@ public InvocationExpressionSignatureHelpProvider()
 
 internal partial class InvocationExpressionSignatureHelpProviderBase : AbstractOrdinaryMethodSignatureHelpProvider
 {
-    public override bool IsTriggerCharacter(char ch)
-        => ch is '(' or ',';
+    public override ImmutableArray<char> TriggerCharacters => ['(', ','];
 
-    public override bool IsRetriggerCharacter(char ch)
-        => ch == ')';
+    public override ImmutableArray<char> RetriggerCharacters => [')'];
 
     private async Task<InvocationExpressionSyntax?> TryGetInvocationExpressionAsync(Document document, int position, SignatureHelpTriggerReason triggerReason, CancellationToken cancellationToken)
     {
@@ -54,7 +52,7 @@ public override bool IsRetriggerCharacter(char ch)
     }
 
     private bool IsTriggerToken(SyntaxToken token)
-        => SignatureHelpUtilities.IsTriggerParenOrComma<InvocationExpressionSyntax>(token, IsTriggerCharacter);
+        => SignatureHelpUtilities.IsTriggerParenOrComma<InvocationExpressionSyntax>(token, TriggerCharacters);
 
     private static bool IsArgumentListToken(InvocationExpressionSyntax expression, SyntaxToken token)
     {

src/Features/CSharp/Portable/SignatureHelp/ObjectCreationExpressionSignatureHelpProvider.cs

@@ -3,6 +3,7 @@
 // See the LICENSE file in the project root for more information.
 
 using System;
+using System.Collections.Immutable;
 using System.Composition;
 using System.Diagnostics;
 using System.Threading;
@@ -22,11 +23,9 @@ namespace Microsoft.CodeAnalysis.CSharp.SignatureHelp;
 [method: Obsolete(MefConstruction.ImportingConstructorMessage, error: true)]
 internal sealed partial class ObjectCreationExpressionSignatureHelpProvider() : AbstractCSharpSignatureHelpProvider
 {
-    public override bool IsTriggerCharacter(char ch)
-        => ch is '(' or ',';
+    public override ImmutableArray<char> TriggerCharacters => ['(', ','];
 
-    public override bool IsRetriggerCharacter(char ch)
-        => ch == ')';
+    public override ImmutableArray<char> RetriggerCharacters => [')'];
 
     private async Task<BaseObjectCreationExpressionSyntax?> TryGetObjectCreationExpressionAsync(
         Document document,
@@ -50,7 +49,7 @@ public override bool IsRetriggerCharacter(char ch)
     }
 
     private bool IsTriggerToken(SyntaxToken token)
-        => SignatureHelpUtilities.IsTriggerParenOrComma<BaseObjectCreationExpressionSyntax>(token, IsTriggerCharacter);
+        => SignatureHelpUtilities.IsTriggerParenOrComma<BaseObjectCreationExpressionSyntax>(token, TriggerCharacters);
 
     private static bool IsArgumentListToken(BaseObjectCreationExpressionSyntax expression, SyntaxToken token)
     {

src/Features/CSharp/Portable/SignatureHelp/PrimaryConstructorBaseTypeSignatureHelpProvider.cs

@@ -4,6 +4,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Collections.Immutable;
 using System.Composition;
 using System.Diagnostics.CodeAnalysis;
 using System.Linq;
@@ -35,11 +36,9 @@ public PrimaryConstructorBaseTypeSignatureHelpProvider()
     {
     }
 
-    public override bool IsTriggerCharacter(char ch)
-        => ch is '(' or ',';
+    public override ImmutableArray<char> TriggerCharacters => ['(', ','];
 
-    public override bool IsRetriggerCharacter(char ch)
-        => ch == ')';
+    public override ImmutableArray<char> RetriggerCharacters => [')'];
 
     private bool TryGetBaseTypeSyntax(
         SyntaxNode root,
@@ -65,7 +64,7 @@ static bool IsArgumentListToken(PrimaryConstructorBaseTypeSyntax expression, Syn
     }
 
     private bool IsTriggerToken(SyntaxToken token)
-        => SignatureHelpUtilities.IsTriggerParenOrComma<PrimaryConstructorBaseTypeSyntax>(token, IsTriggerCharacter);
+        => SignatureHelpUtilities.IsTriggerParenOrComma<PrimaryConstructorBaseTypeSyntax>(token, TriggerCharacters);
 
     protected override async Task<SignatureHelpItems?> GetItemsWorkerAsync(Document document, int position, SignatureHelpTriggerInfo triggerInfo, MemberDisplayOptions options, CancellationToken cancellationToken)
     {

src/Features/CSharp/Portable/SignatureHelp/SignatureHelpUtilities.cs

@@ -10,6 +10,7 @@
 using Microsoft.CodeAnalysis.SignatureHelp;
 using Microsoft.CodeAnalysis.Text;
 using Microsoft.CodeAnalysis.Shared.Extensions;
+using System.Collections.Immutable;
 
 namespace Microsoft.CodeAnalysis.CSharp.SignatureHelp;
 
@@ -96,7 +97,7 @@ internal static TextSpan GetSignatureHelpSpan(InitializerExpressionSyntax initia
     internal static TextSpan GetSignatureHelpSpan(AttributeArgumentListSyntax argumentList)
         => CommonSignatureHelpUtilities.GetSignatureHelpSpan(argumentList, s_getAttributeArgumentListCloseToken);
 
-    internal static bool IsTriggerParenOrComma<TSyntaxNode>(SyntaxToken token, Func<char, bool> isTriggerCharacter) where TSyntaxNode : SyntaxNode
+    internal static bool IsTriggerParenOrComma<TSyntaxNode>(SyntaxToken token, ImmutableArray<char> triggerCharacters) where TSyntaxNode : SyntaxNode
     {
         // Don't dismiss if the user types ( to start a parenthesized expression or tuple
         // Note that the tuple initially parses as a parenthesized expression 
@@ -134,7 +135,7 @@ internal static bool IsTriggerParenOrComma<TSyntaxNode>(SyntaxToken token, Func<
 
         return !token.IsKind(SyntaxKind.None) &&
             token.ValueText.Length == 1 &&
-            isTriggerCharacter(token.ValueText[0]) &&
+            triggerCharacters.Contains(token.ValueText[0]) &&
             token.Parent is ArgumentListSyntax &&
             token.Parent.Parent is TSyntaxNode;
     }