Replace interface-based collection types in ElementCompletionResult with concrete types

Co-authored-by: davidwengier <754264+davidwengier@users.noreply.github.com>

Author: Copilot

src/Razor/src/Microsoft.AspNetCore.Razor.ExternalAccess.LegacyEditor/RazorWrapperFactory.TagHelperCompletionServiceWrapper.cs

@@ -26,12 +26,10 @@ public ImmutableDictionary<string, ImmutableArray<IRazorTagHelperDescriptor>> Ge
         {
             var result = Object.GetElementCompletions(Unwrap(completionContext));
 
-            var completions = (Dictionary<string, IEnumerable<TagHelperDescriptor>>)result.Completions;
-
-            return completions.ToImmutableDictionary(
+            return result.Completions.ToImmutableDictionary(
                 keySelector: kvp => kvp.Key,
                 elementSelector: kvp => WrapAll(kvp.Value, Wrap),
-                keyComparer: completions.Comparer);
+                keyComparer: result.Comparer);
         }
     }
 }

src/Razor/src/Microsoft.AspNetCore.Razor.ExternalAccess.LegacyEditor/RazorWrapperFactory.cs

@@ -58,20 +58,6 @@ private static ImmutableArray<TResult> WrapAll<TInner, TResult>(ImmutableArray<T
         return builder.ToImmutableAndClear();
     }
 
-    private static ImmutableArray<TResult> WrapAll<TInner, TResult>(IEnumerable<TInner> items, Func<TInner, TResult> createWrapper)
-        where TInner : class
-        where TResult : class
-    {
-        using var builder = new PooledArrayBuilder<TResult>();
-
-        foreach (var item in items)
-        {
-            builder.Add(createWrapper(item));
-        }
-
-        return builder.ToImmutableAndClear();
-    }
-
     private static ImmutableArray<TResult> InitializeArrayWithWrappedItems<TInner, TResult>(
         ref ImmutableArray<TResult> location,
         ImmutableArray<TInner> list,

src/Razor/src/Microsoft.CodeAnalysis.Razor.Workspaces/Completion/ElementCompletionResult.cs

@@ -3,17 +3,22 @@
 
 using System;
 using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.Collections.ObjectModel;
 using Microsoft.AspNetCore.Razor.Language;
 
 namespace Microsoft.CodeAnalysis.Razor.Completion;
 
 internal sealed class ElementCompletionResult
 {
-    public IReadOnlyDictionary<string, IEnumerable<TagHelperDescriptor>> Completions { get; }
+    public ReadOnlyDictionary<string, ImmutableArray<TagHelperDescriptor>> Completions { get; }
 
-    private ElementCompletionResult(IReadOnlyDictionary<string, IEnumerable<TagHelperDescriptor>> completions)
+    public IEqualityComparer<string> Comparer { get; }
+
+    private ElementCompletionResult(ReadOnlyDictionary<string, ImmutableArray<TagHelperDescriptor>> completions, IEqualityComparer<string> comparer)
     {
         Completions = completions;
+        Comparer = comparer;
     }
 
     internal static ElementCompletionResult Create(Dictionary<string, HashSet<TagHelperDescriptor>> completions)
@@ -23,15 +28,15 @@ internal static ElementCompletionResult Create(Dictionary<string, HashSet<TagHel
             throw new ArgumentNullException(nameof(completions));
         }
 
-        var readonlyCompletions = new Dictionary<string, IEnumerable<TagHelperDescriptor>>(
+        var readonlyCompletions = new Dictionary<string, ImmutableArray<TagHelperDescriptor>>(
             capacity: completions.Count,
             comparer: completions.Comparer);
 
         foreach (var (key, value) in completions)
         {
-            readonlyCompletions.Add(key, value);
+            readonlyCompletions.Add(key, value.ToImmutableArray());
         }
 
-        return new ElementCompletionResult(readonlyCompletions);
+        return new ElementCompletionResult(new ReadOnlyDictionary<string, ImmutableArray<TagHelperDescriptor>>(readonlyCompletions), completions.Comparer);
     }
 }

src/Razor/test/Microsoft.CodeAnalysis.Razor.Workspaces.Test/Completion/LanguageServerTagHelperCompletionServiceTest.cs

@@ -1436,9 +1436,8 @@ private static void AssertCompletionsAreEquivalent(ElementCompletionResult expec
 
         foreach (var (key, value) in expected.Completions)
         {
-            var actualValue = actual.Completions[key];
-            Assert.NotNull(actualValue);
-            Assert.Equal(value, actualValue);
+            Assert.True(actual.Completions.TryGetValue(key, out var actualValue), $"Key '{key}' not found in actual completions");
+            Assert.True(value.SequenceEqual(actualValue), $"Values for key '{key}' do not match");
         }
     }
 

src/Razor/test/Microsoft.VisualStudio.LegacyEditor.Razor.Test/Completion/LegacyTagHelperCompletionServiceTest.cs

@@ -1358,9 +1358,8 @@ private static void AssertCompletionsAreEquivalent(ElementCompletionResult expec
 
         foreach (var expectedCompletion in expected.Completions)
         {
-            var actualValue = actual.Completions[expectedCompletion.Key];
-            Assert.NotNull(actualValue);
-            Assert.Equal(expectedCompletion.Value, actualValue);
+            Assert.True(actual.Completions.TryGetValue(expectedCompletion.Key, out var actualValue), $"Key '{expectedCompletion.Key}' not found in actual completions");
+            Assert.True(expectedCompletion.Value.SequenceEqual(actualValue), $"Values for key '{expectedCompletion.Key}' do not match");
         }
     }