Implement color presentation

Sources/LanguageServerProtocol/ColorPresentationRequest.swift

@@ -0,0 +1,68 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2019 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
+//
+//===----------------------------------------------------------------------===//
+
+/// The color presentation request is sent from the client to the server to obtain 
+/// a list of presentations for a color value at a given location. Clients can 
+/// use the result to modify a color reference, or show in a color picker 
+/// and let users pick one of the presentations
+///
+/// - Parameters:
+///   - textDocument: The document to request presentations for.
+///   - color: The color information to request presentations for.
+///   - range: The range where the color would be inserted. Serves as a context.
+///
+/// - Returns: A list of color presentations for the given document.
+public struct ColorPresentationRequest: TextDocumentRequest, Hashable {
+  public static let method: String = "textDocument/colorPresentation"
+  public typealias Response = [ColorPresentation]?
+
+  /// The document to request presentations for.
+  public var textDocument: TextDocumentIdentifier
+
+  /// The color information to request presentations for.
+  public var color: Color
+
+  /// The range where the color would be inserted. Serves as a context.
+  public var range: PositionRange
+
+  public init(
+    textDocument: TextDocumentIdentifier, 
+    color: Color, 
+    range: Range<Position>) 
+  {
+    self.textDocument = textDocument
+    self.color = color
+    self.range = PositionRange(range)
+  }
+}
+
+public struct ColorPresentation: ResponseType, Hashable {
+  /// The label of this color presentation. It will be shown on the color
+  /// picker header. By default this is also the text that is inserted when 
+  /// selecting this color presentation.
+  public var label: String
+
+  /// An edit which is applied to a document when selecting this
+  /// presentation for the color.  When `falsy` the label is used.
+  public var textEdit: TextEdit?
+
+  /// An optional array of additional text edits that are applied when
+  /// selecting this color presentation. Edits must not overlap with 
+  /// the main edit nor with themselves.
+  public var additionalTextEdits: [TextEdit]?
+
+  public init(label: String, textEdit: TextEdit?, additionalTextEdits: [TextEdit]?) {
+    self.label = label
+    self.textEdit = textEdit
+    self.additionalTextEdits = additionalTextEdits
+  }
+}

Sources/LanguageServerProtocol/DocumentColor.swift

@@ -0,0 +1,64 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2019 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
+//
+//===----------------------------------------------------------------------===//
+
+/// The document color request is sent from the client to the server to list
+/// all color references found in a given text document. Along with the range, 
+/// a color value in RGB is returned.
+/// Clients can use the result to decorate color references in an editor. 
+///
+/// - Parameters:
+///   - textDocument: The document to search for color references.
+///
+/// - Returns: A list of color references for the given document.
+public struct DocumentColorRequest: TextDocumentRequest, Hashable {
+  public static let method: String = "textDocument/documentColor"
+  public typealias Response = [ColorInformation]?
+
+  /// The document in which to search for color references.
+  public var textDocument: TextDocumentIdentifier
+
+  public init(textDocument: TextDocumentIdentifier) {
+    self.textDocument = textDocument
+  }
+}
+
+public struct ColorInformation: ResponseType, Hashable {
+  /// The range in the document where this color appears.
+  public var range: PositionRange
+
+  /// The actual color value for this color range.
+  public var color: Color
+
+  public init(range: Range<Position>, color: Color) {
+    self.range = PositionRange(range)
+    self.color = color
+  }
+}
+
+/// Represents a color in RGBA space.
+public struct Color: Hashable, Codable {
+  /// The red component of this color in the range [0-1].
+  public var red: Double
+  /// The green component of this color in the range [0-1].
+  public var green: Double
+  /// The blue component of this color in the range [0-1].
+  public var blue: Double
+  /// The alpha component of this color in the range [0-1].
+  public var alpha: Double
+
+  public init(red: Double, green: Double, blue: Double, alpha: Double) {
+    self.red = red
+    self.green = green
+    self.blue = blue
+    self.alpha = alpha
+  }
+}

Sources/LanguageServerProtocol/Messages.swift

@@ -31,6 +31,8 @@ public let builtinRequests: [_RequestType.Type] = [
   DocumentOnTypeFormatting.self,
   FoldingRangeRequest.self,
   DocumentSymbolRequest.self,
+  DocumentColorRequest.self,
+  ColorPresentationRequest.self,
 
   // MARK: LSP Extension Requests
 

Sources/LanguageServerProtocol/ServerCapabilities.swift

@@ -45,6 +45,9 @@ public struct ServerCapabilities: Codable, Hashable {
   /// Whether the server provides "textDocument/documentSymbol"
   public var documentSymbolProvider: Bool?
 
+  /// Whether the server provides "textDocument/documentColor" and "textDocument/colorPresentation".
+  public var colorProvider: Bool?
+
   // TODO: fill-in the rest.
 
   public init(
@@ -58,7 +61,8 @@ public struct ServerCapabilities: Codable, Hashable {
     documentRangeFormattingProvider: Bool? = nil,
     documentOnTypeFormattingProvider: DocumentOnTypeFormattingOptions? = nil,
     foldingRangeProvider: Bool? = nil,
-    documentSymbolProvider: Bool? = nil
+    documentSymbolProvider: Bool? = nil,
+    colorProvider: Bool? = nil
     )
   {
     self.textDocumentSync = textDocumentSync
@@ -72,6 +76,7 @@ public struct ServerCapabilities: Codable, Hashable {
     self.documentOnTypeFormattingProvider = documentOnTypeFormattingProvider
     self.foldingRangeProvider = foldingRangeProvider
     self.documentSymbolProvider = documentSymbolProvider
+    self.colorProvider = colorProvider
   }
 
   public init(from decoder: Decoder) throws {
@@ -81,6 +86,7 @@ public struct ServerCapabilities: Codable, Hashable {
     self.definitionProvider = try container.decodeIfPresent(Bool.self, forKey: .definitionProvider)
     self.foldingRangeProvider = try container.decodeIfPresent(Bool.self, forKey: .foldingRangeProvider)
     self.documentSymbolProvider = try container.decodeIfPresent(Bool.self, forKey: .documentSymbolProvider)
+    self.colorProvider = try container.decodeIfPresent(Bool.self, forKey: .colorProvider)
 
     if let textDocumentSync = try? container.decode(TextDocumentSyncOptions.self, forKey: .textDocumentSync) {
       self.textDocumentSync = textDocumentSync

Sources/SourceKit/SourceKitServer.swift

@@ -77,6 +77,8 @@ public final class SourceKitServer: LanguageServer {
     registerWorkspaceRequest(SourceKitServer.foldingRange)
     registerWorkspaceRequest(SourceKitServer.symbolInfo)
     registerWorkspaceRequest(SourceKitServer.documentSymbol)
+    registerWorkspaceRequest(SourceKitServer.documentColor)
+    registerWorkspaceRequest(SourceKitServer.colorPresentation)
   }
 
   func registerWorkspaceRequest<R>(
@@ -260,7 +262,8 @@ extension SourceKitServer {
       referencesProvider: true,
       documentHighlightProvider: true,
       foldingRangeProvider: true,
-      documentSymbolProvider: true
+      documentSymbolProvider: true,
+      colorProvider: true
     )))
   }
 
@@ -346,6 +349,14 @@ extension SourceKitServer {
     toolchainTextDocumentRequest(req, workspace: workspace, fallback: nil)
   }
 
+  func documentColor(_ req: Request<DocumentColorRequest>, workspace: Workspace) {
+    toolchainTextDocumentRequest(req, workspace: workspace, fallback: nil)
+  }
+
+  func colorPresentation(_ req: Request<ColorPresentationRequest>, workspace: Workspace) {
+    toolchainTextDocumentRequest(req, workspace: workspace, fallback: nil)
+  }
+
   func definition(_ req: Request<DefinitionRequest>, workspace: Workspace) {
     // FIXME: sending yourself a request isn't very convenient
 

Sources/SourceKit/sourcekitd/SwiftLanguageServer.swift

@@ -64,6 +64,8 @@ public final class SwiftLanguageServer: LanguageServer {
     _register(SwiftLanguageServer.foldingRange)
     _register(SwiftLanguageServer.symbolInfo)
     _register(SwiftLanguageServer.documentSymbol)
+    _register(SwiftLanguageServer.documentColor)
+    _register(SwiftLanguageServer.colorPresentation)
   }
 
   func getDiagnostic(_ diag: SKResponseDictionary, for snapshot: DocumentSnapshot) -> Diagnostic? {
@@ -193,7 +195,8 @@ extension SwiftLanguageServer {
       referencesProvider: nil,
       documentHighlightProvider: true,
       foldingRangeProvider: true,
-      documentSymbolProvider: true
+      documentSymbolProvider: true,
+      colorProvider: true
       )))
   }
 
@@ -553,6 +556,107 @@ extension SwiftLanguageServer {
     return
   }
 
+  func documentColor(_ req: Request<DocumentColorRequest>) {
+    guard let snapshot = documentManager.latestSnapshot(req.params.textDocument.url) else {
+      log("failed to find snapshot for url \(req.params.textDocument.url)")
+      req.reply(nil)
+      return
+    }
+
+    let skreq = SKRequestDictionary(sourcekitd: sourcekitd)
+    skreq[keys.request] = requests.editor_open
+    skreq[keys.name] = "DocumentColor:" + snapshot.document.url.path
+    skreq[keys.sourcetext] = snapshot.text
+    skreq[keys.syntactic_only] = 1
+
+    let handle = sourcekitd.send(skreq) { [weak self] result in      
+      guard let self = self else { return }
+      guard let dict = result.success else {
+        req.reply(.failure(result.failure!))
+        return
+      }
+
+      guard let results: SKResponseArray = dict[self.keys.substructure] else {
+        return req.reply([])
+      }
+
+      func colorInformation(dict: SKResponseDictionary) -> ColorInformation? {
+        guard let kind: sourcekitd_uid_t = dict[self.keys.kind],
+              kind == self.values.expr_object_literal,
+              let name: String = dict[self.keys.name],
+              name == "colorLiteral",
+              let offset: Int = dict[self.keys.offset],
+              let start: Position = snapshot.positionOf(utf8Offset: offset),
+              let length: Int = dict[self.keys.length],
+              let end: Position = snapshot.positionOf(utf8Offset: offset + length),
+              let substructure: SKResponseArray = dict[self.keys.substructure] else {
+          return nil
+        }
+        var red, green, blue, alpha: Double?
+        substructure.forEach{ (i: Int, value: SKResponseDictionary) in
+          guard let name: String = value[self.keys.name],
+                let bodyoffset: Int = value[self.keys.bodyoffset],
+                let bodylength: Int = value[self.keys.bodylength] else {
+            return true
+          }
+          let view = snapshot.text.utf8
+          let bodyStart = view.index(view.startIndex, offsetBy: bodyoffset)
+          let bodyEnd = view.index(view.startIndex, offsetBy: bodyoffset+bodylength)
+          let value = String(view[bodyStart..<bodyEnd]).flatMap(Double.init)
+          switch name {
+            case "red":
+              red = value
+            case "green":
+              green = value
+            case "blue":
+              blue = value
+            case "alpha":
+              alpha = value
+            default:
+              break
+          }
+          return true
+        }
+        if let red = red,
+           let green = green,
+           let blue = blue,
+           let alpha = alpha {
+          let color = Color(red: red, green: green, blue: blue, alpha: alpha)
+          return ColorInformation(range: start..<end, color: color)
+        } else {
+          return nil
+        }
+      }
+
+      func colorInformation(array: SKResponseArray) -> [ColorInformation] {
+        var result: [ColorInformation] = []
+        array.forEach { (i: Int, value: SKResponseDictionary) in
+          if let documentSymbol = colorInformation(dict: value) {
+            result.append(documentSymbol)
+          } else if let substructure: SKResponseArray = value[self.keys.substructure] {
+            result += colorInformation(array: substructure)
+          }
+          return true
+        }
+        return result
+      }
+
+      req.reply(colorInformation(array: results))
+    }
+    // FIXME: cancellation
+    _ = handle
+  }
+
+  func colorPresentation(_ req: Request<ColorPresentationRequest>) {
+    let color = req.params.color
+    // Empty string as a label breaks VSCode color picker
+    let label = "Color Literal"
+    let newText = "#colorLiteral(red: \(color.red), green: \(color.green), blue: \(color.blue), alpha: \(color.alpha))"
+    let textEdit = TextEdit(range: req.params.range.asRange, newText: newText)
+    let presentation = ColorPresentation(label: label, textEdit: textEdit, additionalTextEdits: nil)
+    req.reply([presentation])
+  }
+
   func documentSymbolHighlight(_ req: Request<DocumentHighlightRequest>) {
 
     guard let snapshot = documentManager.latestSnapshot(req.params.textDocument.url) else {

Sources/SourceKit/sourcekitd/SwiftSourceKitFramework.swift

@@ -359,6 +359,7 @@ struct sourcekitd_values {
   let syntaxtype_comment_url: sourcekitd_uid_t
   let syntaxtype_doccomment: sourcekitd_uid_t
   let syntaxtype_doccomment_field: sourcekitd_uid_t
+  let expr_object_literal: sourcekitd_uid_t
 
   let kind_keyword: sourcekitd_uid_t
 
@@ -448,6 +449,7 @@ struct sourcekitd_values {
     syntaxtype_comment_url = api.uid_get_from_cstr("source.lang.swift.syntaxtype.comment.url")!
     syntaxtype_doccomment = api.uid_get_from_cstr("source.lang.swift.syntaxtype.doccomment")!
     syntaxtype_doccomment_field = api.uid_get_from_cstr("source.lang.swift.syntaxtype.doccomment.field")!
+    expr_object_literal = api.uid_get_from_cstr("source.lang.swift.expr.object_literal")!
 
     kind_keyword = api.uid_get_from_cstr("source.lang.swift.keyword")!
   }