Merge pull request swiftlang#1478 from bnbarham/merge-trivia

Add a function to merge trivia from a node into an existing trivia

Author: bnbarham

CodeGeneration/Sources/generate-swiftsyntax/GenerateSwiftSyntax.swift

@@ -106,7 +106,7 @@ struct GenerateSwiftSyntax: ParsableCommand {
         GeneratedFileSpec(swiftSyntaxGeneratedDir + ["SyntaxVisitor.swift"], syntaxVisitorFile),
         GeneratedFileSpec(swiftSyntaxGeneratedDir + ["TokenKind.swift"], tokenKindFile),
         GeneratedFileSpec(swiftSyntaxGeneratedDir + ["Tokens.swift"], tokensFile),
-        GeneratedFileSpec(swiftSyntaxGeneratedDir + ["Trivia.swift"], triviaFile),
+        GeneratedFileSpec(swiftSyntaxGeneratedDir + ["TriviaPieces.swift"], triviaPiecesFile),
 
         // SwiftSyntaxBuilder
         GeneratedFileSpec(swiftSyntaxBuilderGeneratedDir + ["BuildableCollectionNodes.swift"], buildableCollectionNodesFile),

CodeGeneration/Sources/generate-swiftsyntax/templates/swiftsyntax/TriviaFile.swift renamed to CodeGeneration/Sources/generate-swiftsyntax/templates/swiftsyntax/TriviaPiecesFile.swift

@@ -15,16 +15,7 @@ import SwiftSyntaxBuilder
 import SyntaxSupport
 import Utils
 
-let triviaFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
-  DeclSyntax(
-    """
-    public enum TriviaPosition {
-      case leading
-      case trailing
-    }
-    """
-  )
-
+let triviaPiecesFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
   try! EnumDeclSyntax(
     """
     /// A contiguous stretch of a single kind of trivia. The constituent part of
@@ -115,88 +106,11 @@ let triviaFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
     }
   }
 
-  DeclSyntax(
-    """
-    extension TriviaPiece {
-      /// Returns true if the trivia is `.newlines`, `.carriageReturns` or `.carriageReturnLineFeeds`
-      public var isNewline: Bool {
-        switch self {
-        case .newlines,
-            .carriageReturns,
-            .carriageReturnLineFeeds:
-          return true
-        default:
-          return false
-        }
-      }
-    }
-    """
-  )
-
-  try! StructDeclSyntax(
+  try! ExtensionDeclSyntax(
     """
-    /// A collection of leading or trailing trivia. This is the main data structure
-    /// for thinking about trivia.
-    public struct Trivia
+    extension Trivia
     """
   ) {
-    DeclSyntax("public let pieces: [TriviaPiece]")
-
-    DeclSyntax(
-      """
-      /// Creates Trivia with the provided underlying pieces.
-      public init<S: Sequence>(pieces: S) where S.Element == TriviaPiece {
-        self.pieces = Array(pieces)
-      }
-      """
-    )
-
-    DeclSyntax(
-      """
-      /// Creates Trivia with no pieces.
-      public static var zero: Trivia {
-        return Trivia(pieces: [])
-      }
-      """
-    )
-
-    DeclSyntax(
-      """
-      /// Whether the Trivia contains no pieces.
-      public var isEmpty: Bool {
-        pieces.isEmpty
-      }
-      """
-    )
-
-    DeclSyntax(
-      """
-      /// Creates a new `Trivia` by appending the provided `TriviaPiece` to the end.
-      public func appending(_ piece: TriviaPiece) -> Trivia {
-        var copy = pieces
-        copy.append(piece)
-        return Trivia(pieces: copy)
-      }
-      """
-    )
-
-    DeclSyntax(
-      """
-      public var sourceLength: SourceLength {
-        return pieces.map({ $0.sourceLength }).reduce(.zero, +)
-      }
-      """
-    )
-
-    DeclSyntax(
-      """
-      /// Get the byteSize of this trivia
-      public var byteSize: Int {
-        return sourceLength.utf8Length
-      }
-      """
-    )
-
     for trivia in TRIVIAS {
       if trivia.isCollection {
         let joined = trivia.characters.map { "\($0)" }.joined()
@@ -231,99 +145,6 @@ let triviaFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
     }
   }
 
-  DeclSyntax(
-    #"""
-    extension Trivia: CustomDebugStringConvertible {
-      public var debugDescription: String {
-        if count == 1, let first = first {
-          return first.debugDescription
-        }
-        return "[" + map(\.debugDescription).joined(separator: ", ") + "]"
-      }
-    }
-    """#
-  )
-
-  DeclSyntax("extension Trivia: Equatable {}")
-
-  DeclSyntax(
-    """
-    /// Conformance for Trivia to the Collection protocol.
-    extension Trivia: Collection {
-      public var startIndex: Int {
-        return pieces.startIndex
-      }
-
-      public var endIndex: Int {
-        return pieces.endIndex
-      }
-
-      public func index(after i: Int) -> Int {
-        return pieces.index(after: i)
-      }
-
-      public subscript(_ index: Int) -> TriviaPiece {
-        return pieces[index]
-      }
-    }
-    """
-  )
-
-  DeclSyntax(
-    """
-    extension Trivia: ExpressibleByArrayLiteral {
-      /// Creates Trivia from the provided pieces.
-      public init(arrayLiteral elements: TriviaPiece...) {
-        self.pieces = elements
-      }
-    }
-    """
-  )
-
-  DeclSyntax(
-    """
-    extension Trivia: TextOutputStreamable {
-      /// Prints the provided trivia as they would be written in a source file.
-      ///
-      /// - Parameter stream: The stream to which to print the trivia.
-      public func write<Target>(to target: inout Target)
-      where Target: TextOutputStream {
-        for piece in pieces {
-          piece.write(to: &target)
-        }
-      }
-    }
-    """
-  )
-
-  DeclSyntax(
-    """
-    extension Trivia: CustomStringConvertible {
-      public var description: String {
-        var description = ""
-        self.write(to: &description)
-        return description
-      }
-    }
-    """
-  )
-
-  DeclSyntax(
-    """
-    extension Trivia {
-      /// Concatenates two collections of `Trivia` into one collection.
-      public static func +(lhs: Trivia, rhs: Trivia) -> Trivia {
-        return Trivia(pieces: lhs.pieces + rhs.pieces)
-      }
-
-      /// Concatenates two collections of `Trivia` into the left-hand side.
-      public static func +=(lhs: inout Trivia, rhs: Trivia) {
-        lhs = lhs + rhs
-      }
-    }
-    """
-  )
-
   DeclSyntax("extension TriviaPiece: Equatable {}")
 
   try! ExtensionDeclSyntax("extension TriviaPiece") {
@@ -388,26 +209,6 @@ let triviaFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
     }
   }
 
-  DeclSyntax(
-    """
-    extension RawTriviaPiece: TextOutputStreamable {
-      public func write<Target: TextOutputStream>(to target: inout Target) {
-        TriviaPiece(raw: self).write(to: &target)
-      }
-    }
-    """
-  )
-
-  DeclSyntax(
-    """
-    extension RawTriviaPiece: CustomDebugStringConvertible {
-      public var debugDescription: String {
-        TriviaPiece(raw: self).debugDescription
-      }
-    }
-    """
-  )
-
   try! ExtensionDeclSyntax("extension TriviaPiece") {
     try InitializerDeclSyntax("@_spi(RawSyntax) public init(raw: RawTriviaPiece)") {
       try SwitchExprSyntax("switch raw") {
@@ -463,22 +264,4 @@ let triviaFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
       }
     }
   }
-
-  DeclSyntax(
-    """
-    extension RawTriviaPiece {
-      /// Returns true if the trivia is `.newlines`, `.carriageReturns` or `.carriageReturnLineFeeds`
-      public var isNewline: Bool {
-        switch self {
-        case .newlines,
-            .carriageReturns,
-            .carriageReturnLineFeeds:
-          return true
-        default:
-          return false
-        }
-      }
-    }
-    """
-  )
 }

Sources/SwiftParserDiagnostics/DiagnosticExtensions.swift

@@ -169,9 +169,9 @@ extension FixIt.MultiNodeChange {
   /// where it makes sense and refusing to add e.g. a space after punctuation,
   /// where it usually doesn't make sense.
   static func transferTriviaAtSides<SyntaxType: SyntaxProtocol>(from nodes: [SyntaxType]) -> Self {
-    let removedTriviaAtSides = Trivia.merged(nodes.first?.leadingTrivia ?? [], nodes.last?.trailingTrivia ?? [])
+    let removedTriviaAtSides = (nodes.first?.leadingTrivia ?? []).merging(nodes.last?.trailingTrivia ?? [])
     if !removedTriviaAtSides.isEmpty, let previousToken = nodes.first?.previousToken(viewMode: .sourceAccurate) {
-      let mergedTrivia = Trivia.merged(previousToken.trailingTrivia, removedTriviaAtSides)
+      let mergedTrivia = previousToken.trailingTrivia.merging(removedTriviaAtSides)
       if previousToken.tokenKind.isPunctuation, mergedTrivia.allSatisfy({ $0.isSpaceOrTab }) {
         // Punctuation is generally not followed by spaces in Swift.
         // If this action would only add spaces to the punctuation, drop it.
@@ -185,49 +185,6 @@ extension FixIt.MultiNodeChange {
   }
 }
 
-extension Trivia {
-  /// Decomposes the trivia into pieces that all have count 1
-  var decomposed: Trivia {
-    let pieces = self.flatMap({ (piece: TriviaPiece) -> [TriviaPiece] in
-      switch piece {
-      case .spaces(let count):
-        return Array(repeating: TriviaPiece.spaces(1), count: count)
-      case .tabs(let count):
-        return Array(repeating: TriviaPiece.tabs(1), count: count)
-      case .verticalTabs(let count):
-        return Array(repeating: TriviaPiece.verticalTabs(1), count: count)
-      case .formfeeds(let count):
-        return Array(repeating: TriviaPiece.formfeeds(1), count: count)
-      case .newlines(let count):
-        return Array(repeating: TriviaPiece.newlines(1), count: count)
-      case .backslashes(let count):
-        return Array(repeating: TriviaPiece.backslashes(1), count: count)
-      case .pounds(let count):
-        return Array(repeating: TriviaPiece.pounds(1), count: count)
-      case .carriageReturns(let count):
-        return Array(repeating: TriviaPiece.carriageReturns(1), count: count)
-      case .carriageReturnLineFeeds(let count):
-        return Array(repeating: TriviaPiece.carriageReturnLineFeeds(1), count: count)
-      case .lineComment, .blockComment, .docLineComment, .docBlockComment, .unexpectedText, .shebang:
-        return [piece]
-      }
-    })
-    return Trivia(pieces: pieces)
-  }
-
-  /// Concatenate `lhs` and `rhs`, merging an infix that is shared between both trivia pieces.
-  static func merged(_ lhs: Trivia, _ rhs: Trivia) -> Self {
-    let lhs = lhs.decomposed
-    let rhs = rhs.decomposed
-    for infixLength in (0...Swift.min(lhs.count, rhs.count)).reversed() {
-      if lhs.suffix(infixLength) == rhs.suffix(infixLength) {
-        return lhs + Trivia(pieces: Array(rhs.dropFirst(infixLength)))
-      }
-    }
-    return lhs + rhs
-  }
-}
-
 extension TriviaPiece {
   var isSpaceOrTab: Bool {
     switch self {

Sources/SwiftParserDiagnostics/MultiLineStringLiteralDiagnosticsGenerator.swift

@@ -11,7 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 import SwiftDiagnostics
-import SwiftSyntax
+@_spi(RawSyntax) import SwiftSyntax
 
 /// A diagnostic that `MultiLineStringLiteralIndentatinDiagnosticsGenerator` is building.
 /// As indentation errors are found on more lines, this diagnostic is modified

Sources/SwiftSyntax/CMakeLists.txt

@@ -12,6 +12,7 @@ add_swift_host_library(SwiftSyntax
   BumpPtrAllocator.swift
   CommonAncestor.swift
   IncrementalParseTransition.swift
+  Trivia.swift
   SourceLength.swift
   SourceLocation.swift
   SourcePresence.swift
@@ -46,7 +47,7 @@ add_swift_host_library(SwiftSyntax
   generated/SyntaxVisitor.swift
   generated/TokenKind.swift
   generated/Tokens.swift
-  generated/Trivia.swift
+  generated/TriviaPieces.swift
 
   generated/syntaxNodes/SyntaxDeclNodes.swift
   generated/syntaxNodes/SyntaxExprNodes.swift