Return non-nullable ImmutableArray<T> from GetImportSyntaxTrees()

Author: DustinCampbell

src/Compiler/Microsoft.AspNetCore.Razor.Language/src/DefaultRazorIntermediateNodeLoweringPhase.cs

@@ -122,7 +122,7 @@ protected override void ExecuteCore(RazorCodeDocument codeDocument)
             document.Diagnostics.Add(syntaxTree.Diagnostics[i]);
         }
 
-        if (imports is ImmutableArray<RazorSyntaxTree> importsArray)
+        if (imports is { IsDefault: false } importsArray)
         {
             foreach (var import in importsArray)
             {
@@ -165,15 +165,15 @@ private static IReadOnlyList<UsingReference> ImportDirectives(
         DocumentIntermediateNode document,
         IntermediateNodeBuilder builder,
         RazorParserOptions options,
-        ImmutableArray<RazorSyntaxTree>? imports)
+        ImmutableArray<RazorSyntaxTree> imports)
     {
-        if (imports == null)
+        if (imports.IsDefaultOrEmpty)
         {
             return Array.Empty<UsingReference>();
         }
 
         var importsVisitor = new ImportsVisitor(document, builder, options.FeatureFlags);
-        foreach (var import in imports.GetValueOrDefault())
+        foreach (var import in imports)
         {
             importsVisitor.SourceDocument = import.Source;
             importsVisitor.Visit(import.Root);

src/Compiler/Microsoft.AspNetCore.Razor.Language/src/DefaultRazorTagHelperContextDiscoveryPhase.cs

@@ -51,7 +51,7 @@ protected override void ExecuteCore(RazorCodeDocument codeDocument)
             visitor = new TagHelperDirectiveVisitor(descriptors);
         }
 
-        if (codeDocument.GetImportSyntaxTrees() is ImmutableArray<RazorSyntaxTree> imports)
+        if (codeDocument.GetImportSyntaxTrees() is { IsDefault: false } imports)
         {
             foreach (var import in imports)
             {

src/Compiler/Microsoft.AspNetCore.Razor.Language/src/PublicAPI.Unshipped.txt

@@ -360,7 +360,7 @@ virtual Microsoft.AspNetCore.Razor.Language.RazorEnginePhaseBase.OnInitialized()
 ~static Microsoft.AspNetCore.Razor.Language.BoundAttributeDescriptorExtensions.GetGloballyQualifiedTypeName(this Microsoft.AspNetCore.Razor.Language.BoundAttributeDescriptor attribute) -> string
 ~static Microsoft.AspNetCore.Razor.Language.DirectiveDescriptorBuilderExtensions.AddIdentifierOrExpression(this Microsoft.AspNetCore.Razor.Language.IDirectiveDescriptorBuilder builder, string name, string description) -> Microsoft.AspNetCore.Razor.Language.IDirectiveDescriptorBuilder
 ~static Microsoft.AspNetCore.Razor.Language.Intermediate.IntermediateNodeExtensions.IsDesignTimePropertyAccessHelper(this Microsoft.AspNetCore.Razor.Language.Intermediate.IntermediateNode tagHelper) -> bool
-~static Microsoft.AspNetCore.Razor.Language.RazorCodeDocumentExtensions.GetImportSyntaxTrees(this Microsoft.AspNetCore.Razor.Language.RazorCodeDocument document) -> System.Collections.Immutable.ImmutableArray<Microsoft.AspNetCore.Razor.Language.RazorSyntaxTree>?
+~static Microsoft.AspNetCore.Razor.Language.RazorCodeDocumentExtensions.GetImportSyntaxTrees(this Microsoft.AspNetCore.Razor.Language.RazorCodeDocument document) -> System.Collections.Immutable.ImmutableArray<Microsoft.AspNetCore.Razor.Language.RazorSyntaxTree>
 ~static Microsoft.AspNetCore.Razor.Language.RazorCodeDocumentExtensions.GetPreTagHelperSyntaxTree(this Microsoft.AspNetCore.Razor.Language.RazorCodeDocument document) -> Microsoft.AspNetCore.Razor.Language.RazorSyntaxTree
 ~static Microsoft.AspNetCore.Razor.Language.RazorCodeDocumentExtensions.SetImportSyntaxTrees(this Microsoft.AspNetCore.Razor.Language.RazorCodeDocument document, System.Collections.Immutable.ImmutableArray<Microsoft.AspNetCore.Razor.Language.RazorSyntaxTree> syntaxTrees) -> void
 ~static Microsoft.AspNetCore.Razor.Language.RazorCodeDocumentExtensions.SetPreTagHelperSyntaxTree(this Microsoft.AspNetCore.Razor.Language.RazorCodeDocument document, Microsoft.AspNetCore.Razor.Language.RazorSyntaxTree syntaxTree) -> void

src/Compiler/Microsoft.AspNetCore.Razor.Language/src/RazorCodeDocumentExtensions.cs

@@ -122,14 +122,14 @@ public static void SetSyntaxTree(this RazorCodeDocument document, RazorSyntaxTre
         document.Items[typeof(RazorSyntaxTree)] = syntaxTree;
     }
 
-    public static ImmutableArray<RazorSyntaxTree>? GetImportSyntaxTrees(this RazorCodeDocument document)
+    public static ImmutableArray<RazorSyntaxTree> GetImportSyntaxTrees(this RazorCodeDocument document)
     {
         if (document == null)
         {
             throw new ArgumentNullException(nameof(document));
         }
 
-        return (document.Items[typeof(ImportSyntaxTreesHolder)] as ImportSyntaxTreesHolder)?.SyntaxTrees;
+        return (document.Items[typeof(ImportSyntaxTreesHolder)] as ImportSyntaxTreesHolder)?.SyntaxTrees ?? default;
     }
 
     public static void SetImportSyntaxTrees(this RazorCodeDocument document, ImmutableArray<RazorSyntaxTree> syntaxTrees)
@@ -139,6 +139,11 @@ public static void SetImportSyntaxTrees(this RazorCodeDocument document, Immutab
             throw new ArgumentNullException(nameof(document));
         }
 
+        if (syntaxTrees.IsDefault)
+        {
+            throw new ArgumentException("", nameof(syntaxTrees));
+        }
+
         document.Items[typeof(ImportSyntaxTreesHolder)] = new ImportSyntaxTreesHolder(syntaxTrees);
     }
 
@@ -343,7 +348,7 @@ bool TryComputeNamespaceCore(RazorCodeDocument document, bool fallbackToRootName
             var lastNamespaceContent = string.Empty;
             var lastNamespaceLocation = SourceSpan.Undefined;
 
-            if (document.GetImportSyntaxTrees() is ImmutableArray<RazorSyntaxTree> importSyntaxTrees)
+            if (document.GetImportSyntaxTrees() is { IsDefault: false } importSyntaxTrees)
             {
                 // ImportSyntaxTrees is usually set. Just being defensive.
                 foreach (var importSyntaxTree in importSyntaxTrees)

src/Compiler/Microsoft.AspNetCore.Razor.Language/test/DefaultRazorParsingPhaseTest.cs

@@ -73,8 +73,10 @@ public void Execute_ParsesImports()
         phase.Execute(codeDocument);
 
         // Assert
+        var importSyntaxTrees = codeDocument.GetImportSyntaxTrees();
+        Assert.False(importSyntaxTrees.IsDefault);
         Assert.Collection(
-            codeDocument.GetImportSyntaxTrees().AssumeNotNull(),
+            importSyntaxTrees,
             t => { Assert.Same(t.Source, imports[0]); Assert.Equal("test", Assert.Single(t.Options.Directives).Directive); },
             t => { Assert.Same(t.Source, imports[1]); Assert.Equal("test", Assert.Single(t.Options.Directives).Directive); });
     }

src/Compiler/Microsoft.AspNetCore.Razor.Language/test/RazorCodeDocumentExtensionsTest.cs

@@ -53,9 +53,10 @@ public void GetAndSetImportSyntaxTrees_ReturnsSyntaxTrees()
         codeDocument.SetImportSyntaxTrees(expected);
 
         // Act
-        var actual = codeDocument.GetImportSyntaxTrees().AssumeNotNull();
+        var actual = codeDocument.GetImportSyntaxTrees();
 
         // Assert
+        Assert.False(actual.IsDefault);
         Assert.Equal<RazorSyntaxTree>(expected, actual);
     }