Fix some analyzer diagnostics.

src/driver/Program.cs

@@ -27,11 +27,10 @@ public static async Task<int> Main(string[] args)
         return await parser
             .ParseArguments(
                 args,
-                typeof(ThisAssembly)
+                [.. typeof(ThisAssembly)
                     .Assembly
                     .DefinedTypes
-                    .Where(static type => type.GetCustomAttribute<VerbAttribute>() != null)
-                    .ToArray())
+                    .Where(static type => type.GetCustomAttribute<VerbAttribute>() != null)])
             .MapResult(
                 verb => Unsafe.As<Verb>(verb).RunWithHandlerAsync(cts.Token),
                 static _ => ValueTask.FromResult(1));

src/driver/Verbs/CheckVerb.cs

@@ -31,7 +31,7 @@ protected override async ValueTask<int> RunAsync(CancellationToken cancellationT
 
             try
             {
-                diags = (await doc.GetDiagnosticsAsync(cancellationToken)).ToArray();
+                diags = [.. await doc.GetDiagnosticsAsync(cancellationToken)];
             }
             catch (PathTooLongException)
             {

src/language/core/Semantics/Tree/SemanticNode.cs

@@ -27,7 +27,7 @@ private protected SemanticNode(SyntaxNode syntax)
 
     public IEnumerable<SemanticNode> Ancestors()
     {
-        return Parent?.AncestorsAndSelf() ?? Array.Empty<SemanticNode>();
+        return Parent?.AncestorsAndSelf() ?? [];
     }
 
     public IEnumerable<SemanticNode> AncestorsAndSelf()
@@ -50,7 +50,7 @@ public IEnumerable<SemanticNode> Siblings()
 
     public IEnumerable<SemanticNode> SiblingsAndSelf()
     {
-        foreach (var sibling in Parent?.Children() ?? Array.Empty<SemanticNode>())
+        foreach (var sibling in Parent?.Children() ?? [])
             yield return sibling;
     }
 

src/language/core/Syntax/Tree/SyntaxItem.cs

@@ -28,7 +28,7 @@ internal void SetParent(object parent)
 
     public IEnumerable<SyntaxItem> Ancestors()
     {
-        return Parent?.AncestorsAndSelf() ?? Array.Empty<SyntaxItem>();
+        return Parent?.AncestorsAndSelf() ?? [];
     }
 
     public IEnumerable<SyntaxItem> AncestorsAndSelf()
@@ -51,7 +51,7 @@ public IEnumerable<SyntaxItem> Siblings()
 
     public IEnumerable<SyntaxItem> SiblingsAndSelf()
     {
-        foreach (var sibling in Parent?.Children() ?? Array.Empty<SyntaxItem>())
+        foreach (var sibling in Parent?.Children() ?? [])
             yield return sibling;
     }
 

src/language/core/Syntax/Tree/SyntaxTrivia.cs

@@ -37,7 +37,7 @@ internal SyntaxTrivia(int position, SyntaxTriviaKind kind, string text)
 
     public override IEnumerable<SyntaxTerminal> Children()
     {
-        return Array.Empty<SyntaxTerminal>();
+        return [];
     }
 
     public new IEnumerable<SyntaxTrivia> ChildrenAndSelf()
@@ -47,7 +47,7 @@ public override IEnumerable<SyntaxTerminal> Children()
 
     public override IEnumerable<SyntaxTerminal> Descendants()
     {
-        return Array.Empty<SyntaxTerminal>();
+        return [];
     }
 
     public new IEnumerable<SyntaxTrivia> DescendantsAndSelf()

src/language/tooling/Workspaces/WorkspaceDocument.cs

@@ -36,7 +36,7 @@ internal WorkspaceDocument(Workspace workspace, WorkspaceDocumentAttributes attr
         _state = path;
 
         if (attributes.HasFlag(WorkspaceDocumentAttributes.SuppressDiagnostics))
-            _diagnostics = Array.Empty<Diagnostic>();
+            _diagnostics = [];
     }
 
     public ValueTask<SourceText> GetTextAsync(CancellationToken cancellationToken = default)
@@ -126,13 +126,12 @@ public async ValueTask<IEnumerable<Diagnostic>> GetDiagnosticsAsync(Cancellation
         {
             var semantics = await GetSemanticsAsync(cancellationToken).ConfigureAwait(false);
 
-            _diagnostics = semantics
+            _diagnostics = [.. semantics
                 .Syntax
                 .Diagnostics
                 .Concat(semantics.Diagnostics)
                 .Where(static diag => diag.Severity != DiagnosticSeverity.None)
-                .OrderBy(static diag => diag.Span)
-                .ToArray();
+                .OrderBy(static diag => diag.Span)];
         }
 
         return _diagnostics;

src/runtime/core/Metadata/RuntimeFunction.cs

@@ -16,12 +16,7 @@ internal RuntimeFunction(RuntimeModule module, FunctionDeclarationSemantics func
     }
 
     internal RuntimeFunction(RuntimeModule module, LambdaExpressionSemantics function)
-        : this(
-            module,
-            isPublic: false,
-            $"λ{module.AllocateLambdaId()}",
-            Array.Empty<AttributeSemantics>(),
-            function.Parameters)
+        : this(module, isPublic: false, $"λ{module.AllocateLambdaId()}", attributes: [], function.Parameters)
     {
     }
 

src/tests/DriverTests.cs

@@ -13,7 +13,7 @@ private sealed class DirectoryBuilder
 
         public DirectoryBuilder()
         {
-            Files = ImmutableArray<(string, string)>.Empty;
+            Files = [];
         }
 
         private DirectoryBuilder(ImmutableArray<(string Name, string Contents)> files)

src/tests/QualityTests.cs

@@ -11,7 +11,7 @@ private static Task TestAsync(
         var syntax = SyntaxTree.Parse(
             new StringSourceText($"{name}.cel", contents), SyntaxMode.Module, discardText: true);
         var semantics = SemanticTree.Analyze(
-            syntax, context: null, new LintDiagnosticAnalyzer(new[] { pass }, LintConfiguration.Default));
+            syntax, context: null, new LintDiagnosticAnalyzer([pass], LintConfiguration.Default));
 
         return VerifyDiagnosticsAsync(
             syntax.Diagnostics.Concat(semantics.Diagnostics).OrderBy(static diag => diag.Span), file, name);