Remove some deep nesting that we don't exceed parsing limit in debug builds

Author: DougGregor

Tests/SwiftSyntaxTest/SyntaxVisitorTests.swift

@@ -50,6 +50,29 @@ public class SyntaxVisitorTests: XCTestCase {
       rightBrace: .rightBraceToken(leadingTrivia: [.newlines(1), .spaces(4)])
     )
 
+    let innerCodeBlock = CodeBlockSyntax(
+      leftBrace: .leftBraceToken(),
+      statements: CodeBlockItemListSyntax([
+        CodeBlockItemSyntax(
+          item: CodeBlockItemSyntax.Item(
+            FunctionDeclSyntax(
+              funcKeyword: .keyword(.func, leadingTrivia: [.newlines(1), .spaces(4)], trailingTrivia: .space),
+              name: .identifier("foo"),
+              signature: FunctionSignatureSyntax(
+                parameterClause: FunctionParameterClauseSyntax(
+                  leftParen: .leftParenToken(),
+                  parameters: FunctionParameterListSyntax([]),
+                  rightParen: .rightParenToken(trailingTrivia: .space)
+                )
+              ),
+              body: innerBody
+            )
+          )
+        )
+      ]),
+      rightBrace: .rightBraceToken(leadingTrivia: [.newlines(1), .spaces(2)])
+    )
+
     let source = SourceFileSyntax(
       statements: CodeBlockItemListSyntax([
         CodeBlockItemSyntax(
@@ -82,28 +105,7 @@ public class SyntaxVisitorTests: XCTestCase {
                             rightParen: .rightParenToken(trailingTrivia: .space)
                           )
                         ),
-                        body: CodeBlockSyntax(
-                          leftBrace: .leftBraceToken(),
-                          statements: CodeBlockItemListSyntax([
-                            CodeBlockItemSyntax(
-                              item: CodeBlockItemSyntax.Item(
-                                FunctionDeclSyntax(
-                                  funcKeyword: .keyword(.func, leadingTrivia: [.newlines(1), .spaces(4)], trailingTrivia: .space),
-                                  name: .identifier("foo"),
-                                  signature: FunctionSignatureSyntax(
-                                    parameterClause: FunctionParameterClauseSyntax(
-                                      leftParen: .leftParenToken(),
-                                      parameters: FunctionParameterListSyntax([]),
-                                      rightParen: .rightParenToken(trailingTrivia: .space)
-                                    )
-                                  ),
-                                  body: innerBody
-                                )
-                              )
-                            )
-                          ]),
-                          rightBrace: .rightBraceToken(leadingTrivia: [.newlines(1), .spaces(2)])
-                        )
+                        body: innerCodeBlock
                       )
                     )
                   )