Move SyntaxEnum from gyb to codegen

Author: kimdv

CodeGeneration/Sources/generate-swiftsyntax/GenerateSwiftSyntax.swift

@@ -27,6 +27,7 @@ struct GenerateSwiftSyntax: ParsableCommand {
     try generateTemplates(
       templates: [
         (miscFile, "Misc.swift"),
+        (syntaxEnumFile, "SyntaxEnum.swift"),
       ],
       destination: URL(fileURLWithPath: generatedPath),
       verbose: verbose

CodeGeneration/Sources/generate-swiftsyntax/SyntaxEnumFile.swift

@@ -0,0 +1,50 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2022 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+import SwiftSyntax
+import SwiftSyntaxBuilder
+import SyntaxSupport
+import Utils
+
+let syntaxEnumFile = SourceFile(leadingTrivia: .docLineComment(generateCopyrightHeader(for: "generate-swiftsyntax"))) {
+  EnumDecl("""
+    /// Enum to exhaustively switch over all different syntax nodes.
+    @frozen // FIXME: Not actually stable, works around a miscompile
+    public enum SyntaxEnum
+    """) {
+    EnumCaseDecl("case token(TokenSyntax)")
+    for node in NON_BASE_SYNTAX_NODES {
+      EnumCaseDecl("case \(raw: node.swiftSyntaxKind)(\(raw: node.name))")
+    }
+  }
+  
+  ExtensionDecl("""
+    public extension Syntax
+    """) {
+    FunctionDecl("""
+      /// Get an enum that can be used to exhaustively switch over all syntax nodes.
+      func `as`(_: SyntaxEnum.Type) -> SyntaxEnum
+      """) {
+      SwitchStmt(expression: Expr("raw.kind")) {
+        SwitchCase("case .token:") {
+          ReturnStmt("return .token(TokenSyntax(self)!)")
+        }
+        
+        for node in NON_BASE_SYNTAX_NODES {
+          SwitchCase("case .\(raw: node.swiftSyntaxKind):") {
+            ReturnStmt("return .\(raw: node.swiftSyntaxKind)(\(raw: node.name)(self)!)")
+          }
+        }
+      }
+    }
+  }
+}

Package.swift

@@ -68,7 +68,6 @@ let package = Package(
         "SyntaxAnyVisitor.swift.gyb",
         "SyntaxBaseNodes.swift.gyb",
         "SyntaxCollections.swift.gyb",
-        "SyntaxEnum.swift.gyb",
         "SyntaxFactory.swift.gyb",
         "SyntaxKind.swift.gyb",
         "SyntaxNodes.swift.gyb.template",

Sources/SwiftSyntax/CMakeLists.txt

@@ -35,7 +35,7 @@ add_swift_host_library(SwiftSyntax
   gyb_generated/SyntaxAnyVisitor.swift
   gyb_generated/SyntaxBaseNodes.swift
   gyb_generated/SyntaxCollections.swift
-  gyb_generated/SyntaxEnum.swift
+  generated/SyntaxEnum.swift
   gyb_generated/SyntaxFactory.swift
   gyb_generated/SyntaxKind.swift
   gyb_generated/SyntaxRewriter.swift