Fix trailing space on as keyword

Author: kimdv

CodeGeneration/Package.swift

@@ -62,6 +62,7 @@ let package = Package(
       name: "SyntaxSupport",
       exclude: [
         "gyb_helpers",
+        "AttributeKinds.swift.gyb",
         "AttributeNodes.swift.gyb",
         "AvailabilityNodes.swift.gyb",
         "BuilderInitializableTypes.swift.gyb",

CodeGeneration/Sources/generate-swiftbasicformat/BasicFormatFile.swift

@@ -52,10 +52,10 @@ let basicFormatFile = SourceFile {
       open override func visit(_ node: TokenSyntax) -> TokenSyntax {
         var leadingTrivia = node.leadingTrivia
         var trailingTrivia = node.trailingTrivia
-        if requiresLeadingSpace(node.tokenKind) && leadingTrivia.isEmpty && lastRewrittenToken?.trailingTrivia.isEmpty != false {
+        if requiresLeadingSpace(node) && leadingTrivia.isEmpty && lastRewrittenToken?.trailingTrivia.isEmpty != false {
           leadingTrivia += .space
         }
-        if requiresTrailingSpace(node.tokenKind) && trailingTrivia.isEmpty {
+        if requiresTrailingSpace(node) && trailingTrivia.isEmpty {
           trailingTrivia += .space
         }
         if let keyPath = getKeyPath(Syntax(node)), requiresLeadingNewline(keyPath), !(leadingTrivia.first?.isNewline ?? false) {
@@ -121,8 +121,8 @@ let basicFormatFile = SourceFile {
       }
     }
 
-    FunctionDecl("open func requiresLeadingSpace(_ tokenKind: TokenKind) -> Bool") {
-      SwitchStmt(expression: Expr("tokenKind")) {
+    FunctionDecl("open func requiresLeadingSpace(_ token: TokenSyntax) -> Bool") {
+      SwitchStmt(expression: Expr("token.tokenKind")) {
         for token in SYNTAX_TOKENS {
           if token.requiresLeadingSpace {
             SwitchCase("case .\(raw: token.swiftKind):") {
@@ -136,8 +136,41 @@ let basicFormatFile = SourceFile {
       }
     }
 
-    FunctionDecl("open func requiresTrailingSpace(_ tokenKind: TokenKind) -> Bool") {
-      SwitchStmt(expression: Expr("tokenKind")) {
+    FunctionDecl("open func requiresTrailingSpace(_ token: TokenSyntax) -> Bool") {
+      IfStmt(
+        conditions: ConditionElementList {
+          Expr("[.asKeyword, .initKeyword].contains(token.tokenKind)")
+          OptionalBindingCondition(
+            letOrVarKeyword: .let,
+            pattern: Pattern("nextTokenKind"),
+            initializer: InitializerClause(value: Expr("token.nextToken(viewMode: .sourceAccurate)?.tokenKind"))
+          )
+        }
+      ) {
+        SwitchStmt(expression: Expr("nextTokenKind")) {
+          SwitchCase(
+            label: .case(SwitchCaseLabel {
+              CaseItem(
+                pattern: EnumCasePattern(
+                  period: .period,
+                  caseName: .identifier("exclamationMark")),
+                trailingComma: .comma)
+              CaseItem(
+                pattern: EnumCasePattern(
+                  period: .period,
+                  caseName: .identifier("postfixQuestionMark"))
+              )
+            })) {
+              ReturnStmt("return false")
+            }
+          
+          SwitchCase("default:") {
+            BreakStmt()
+          }
+        }
+      }
+        
+      SwitchStmt(expression: Expr("token.tokenKind")) {
         for token in SYNTAX_TOKENS {
           if token.requiresTrailingSpace {
             SwitchCase("case .\(raw: token.swiftKind):") {

Sources/SwiftBasicFormat/generated/BasicFormat.swift

@@ -48,10 +48,10 @@ open class BasicFormat: SyntaxRewriter {
   open override func visit(_ node: TokenSyntax) -> TokenSyntax {
     var leadingTrivia = node.leadingTrivia
     var trailingTrivia = node.trailingTrivia
-    if requiresLeadingSpace(node.tokenKind) && leadingTrivia.isEmpty && lastRewrittenToken?.trailingTrivia.isEmpty != false {
+    if requiresLeadingSpace(node) && leadingTrivia.isEmpty && lastRewrittenToken?.trailingTrivia.isEmpty != false {
       leadingTrivia += .space
     }
-    if requiresTrailingSpace(node.tokenKind) && trailingTrivia.isEmpty {
+    if requiresTrailingSpace(node) && trailingTrivia.isEmpty {
       trailingTrivia += .space
     }
     if let keyPath = getKeyPath(Syntax(node)), requiresLeadingNewline(keyPath), !(leadingTrivia.first?.isNewline ?? false) {
@@ -113,8 +113,8 @@ open class BasicFormat: SyntaxRewriter {
     }
   }
 
-  open func requiresLeadingSpace(_ tokenKind: TokenKind) -> Bool {
-    switch tokenKind {
+  open func requiresLeadingSpace(_ token: TokenSyntax) -> Bool {
+    switch token.tokenKind {
     case .whereKeyword: 
       return true
     case .catchKeyword: 
@@ -136,8 +136,16 @@ open class BasicFormat: SyntaxRewriter {
     }
   }
 
-  open func requiresTrailingSpace(_ tokenKind: TokenKind) -> Bool {
-    switch tokenKind {
+  open func requiresTrailingSpace(_ token: TokenSyntax) -> Bool {
+    if [.asKeyword, .initKeyword].contains(token.tokenKind), let nextTokenKind = token.nextToken(viewMode: .sourceAccurate)?.tokenKind {
+      switch nextTokenKind {
+      case .exclamationMark, .postfixQuestionMark: 
+        return false
+      default: 
+        break 
+      }
+    }
+    switch token.tokenKind {
     case .associatedtypeKeyword: 
       return true
     case .classKeyword: 

Tests/SwiftSyntaxBuilderTest/InitializerDeclTests.swift

@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 XCTest
+import SwiftSyntax
+import SwiftSyntaxBuilder
+
+final class InitializerDeclTests: XCTestCase {
+  func testInitializerDecl() {
+    let builder = InitializerDecl("""
+      public init?(errorCode: Int) {
+        guard errorCode > 0 else { return nil }
+        self.code = errorCode
+      }
+      """)
+    
+    print(builder.formatted().description)
+    
+    AssertBuildResult(builder, """
+      public init?(errorCode: Int) {
+          guard errorCode > 0 else {
+              return nil
+          }
+          self.code = errorCode
+      }
+      """)
+  }
+}

Tests/SwiftSyntaxBuilderTest/MemberAccessTests.swift

@@ -16,7 +16,7 @@ import SwiftSyntaxBuilder
 
 final class MemberAccessTests: XCTestCase {
   func testMemberAccessExprConvenienceInitializers() {
-    let builder = MemberAccessExpr( base: "Foo", name: "bar")
+    let builder = MemberAccessExpr(base: "Foo", name: "bar")
     AssertBuildResult(builder, "Foo.bar")
   }
 }

Tests/SwiftSyntaxBuilderTest/ReturnStmsTests.swift

@@ -24,4 +24,21 @@ final class ReturnStmtTests: XCTestCase {
       """)
   }
 
+  func testReturnStmtwithAsKeyword() {
+    let testCases: [UInt: (ReturnStmt, String)] = [
+      #line: (ReturnStmt("return self.asProtocol(SyntaxProtocol.self) as? DeclSyntaxProtocol"),
+              "return self.asProtocol(SyntaxProtocol.self) as? DeclSyntaxProtocol"),
+      #line: (ReturnStmt("return 0 as! String"),
+              "return 0 as! String"),
+      #line: (ReturnStmt("return 0 as Double"),
+              "return 0 as Double"),
+      #line: (ReturnStmt("return !myBool"),
+              "return !myBool")
+    ]
+
+    for (line, testCase) in testCases {
+      let (builder, expected) = testCase
+      AssertBuildResult(builder, expected, line: line)
+    }
+  }
 }