WIP: Add doc for added properties

Sort `firstPotentialTokenKind` in alphabetical order

Author: StevenWong12

CodeGeneration/Sources/generate-swiftsyntax/templates/swiftparser/IncrementalParseUtilsFile.swift

@@ -25,6 +25,7 @@ let IncrementalParseUtilsFile = SourceFileSyntax(leadingTrivia: copyrightHeader)
   ) {
     try VariableDeclSyntax(
       """
+        /// This property presents the first potential ``TokenSpec``s of all ``SyntaxKind``s
         @_spi(IncrementalParse)
         public var firstPotentialTokenKind: [TokenSpec]
       """
@@ -33,7 +34,7 @@ let IncrementalParseUtilsFile = SourceFileSyntax(leadingTrivia: copyrightHeader)
 
         for node in NON_BASE_SYNTAX_NODES {
           SwitchCaseSyntax("case .\(node.varOrCaseName):") {
-            StmtSyntax("return [\(raw: Set(node.firstPotentialToken.map{$0.descriptionAsTokenSpec}).joined(separator: ", "))]")
+            StmtSyntax("return [\(raw: Set(node.firstPotentialToken.map{$0.descriptionAsTokenSpec}).sorted().joined(separator: ", "))]")
           }
         }
         SwitchCaseSyntax("default:") {
@@ -44,6 +45,8 @@ let IncrementalParseUtilsFile = SourceFileSyntax(leadingTrivia: copyrightHeader)
 
     try VariableDeclSyntax(
       """
+        /// This property presents children of nodes in the form of ``SyntaxKind``.
+        /// All potential children kinds are listed in the internal array.
         @_spi(RawSyntax)
         public var syntaxLayout: [[SyntaxKind]]
       """
@@ -71,6 +74,9 @@ let IncrementalParseUtilsFile = SourceFileSyntax(leadingTrivia: copyrightHeader)
   ) {
     DeclSyntax(
       """
+      /// This property is used to calculate the next potential token
+      /// of a ``Syntax``, which is essentially the next expected optional child of a node, and will be located by the last
+      /// non-nil child of the node.
       public var nextPotentialTokenChoices: [TokenSpec] {
         if let children = self.layoutView?.children,
           let lastNonNilChildIdx = children.lastIndex(where: { $0 != nil }),

Sources/SwiftParser/Parser.swift

@@ -650,15 +650,17 @@ extension Parser {
   }
 
   func nodeCanBeReused(node: Syntax) -> Bool {
+    var underlyingRaw = node.raw
+
     var lookahead = self.lookahead()
     lookahead.lexemes.advance(by: node.byteSize, currentToken: &lookahead.currentToken)
 
     let currentTokenSpec = PrepareForKeywordMatch(lookahead.currentToken)
 
     if let codeBlockItem = node.as(CodeBlockItemSyntax.self) {
-      return codeBlockItem.item.raw.nextPotentialTokenChoices.allSatisfy { !($0 ~= currentTokenSpec) }
+      underlyingRaw = codeBlockItem.item.raw
     }
 
-    return node.raw.nextPotentialTokenChoices.allSatisfy { !($0 ~= currentTokenSpec) }
+    return underlyingRaw.nextPotentialTokenChoices.allSatisfy { !($0 ~= currentTokenSpec) }
   }
 }