Merge pull request #485 from fwcd/syntax-buildable-wrappers-in-swift

Port `SyntaxBuildableWrappers` to Swift

Author: fwcd

Package.swift

@@ -104,15 +104,18 @@ let package = Package(
           "gyb_helpers",
           "AttributeNodes.swift.gyb",
           "AvailabilityNodes.swift.gyb",
+          "BuilderInitializableTypes.swift.gyb",
           "Classification.swift.gyb",
           "CommonNodes.swift.gyb",
           "DeclNodes.swift.gyb",
+          "ExpressibleAsConformances.swift.gyb",
           "ExprNodes.swift.gyb",
           "GenericNodes.swift.gyb",
           "Kinds.swift.gyb",
           "NodeSerializationCodes.swift.gyb",
           "PatternNodes.swift.gyb",
           "StmtNodes.swift.gyb",
+          "SyntaxBaseKinds.swift.gyb",
           "Tokens.swift.gyb",
           "Traits.swift.gyb",
           "Trivia.swift.gyb",

Sources/SwiftSyntaxBuilderGeneration/BuilderInitializableTypes.swift.gyb

@@ -0,0 +1,25 @@
+%{
+  from gyb_syntax_support import *
+  from gyb_helpers import BUILDER_INITIALIZABLE_TYPES
+  # -*- mode: Swift -*-
+  # Ignore the following admonition; it applies to the resulting .swift file only
+}%
+//// Automatically Generated From BuilderInitializableTypes.swift.gyb.
+//// Do Not Edit Directly!
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+let BUILDER_INITIALIZABLE_TYPES: [String: String?] = [
+% for type, resolved_type in BUILDER_INITIALIZABLE_TYPES.items():
+  "${type}": ${'"' + resolved_type + '"' if resolved_type is not None else 'nil'},
+% end
+]

Sources/SwiftSyntaxBuilderGeneration/ExpressibleAsConformances.swift.gyb

@@ -0,0 +1,29 @@
+%{
+  from gyb_syntax_support import *
+  from gyb_helpers import SYNTAX_BUILDABLE_EXPRESSIBLE_AS_CONFORMANCES
+  # -*- mode: Swift -*-
+  # Ignore the following admonition; it applies to the resulting .swift file only
+}%
+//// Automatically Generated From ExpressibleAsConformances.swift.gyb.
+//// Do Not Edit Directly!
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+let SYNTAX_BUILDABLE_EXPRESSIBLE_AS_CONFORMANCES: [String: [String]] = [
+% for buildable, conformances in SYNTAX_BUILDABLE_EXPRESSIBLE_AS_CONFORMANCES.items():
+  "${buildable}": [
+%   for conformance in conformances:
+    "${conformance}",
+%   end
+  ],
+% end
+]

Sources/SwiftSyntaxBuilderGeneration/Node.swift

@@ -28,18 +28,6 @@ class Node {
   let elementsSeparatedByNewline: Bool
   let collectionElement: String
 
-  var baseType: String {
-    if self.baseKind == "SyntaxCollection" {
-      return "Syntax"
-    } else {
-      return kindToType(kind: baseKind)
-    }
-  }
-
-  var collectionElementType: String {
-    return kindToType(kind: collectionElement)
-  }
-
   /// Returns `True` if this node declares one of the base syntax kinds.
   var isBase: Bool {
     return SyntaxBaseKinds.contains(syntaxKind)

Sources/SwiftSyntaxBuilderGeneration/SyntaxBaseKinds.swift.gyb

@@ -0,0 +1,25 @@
+%{
+  from gyb_syntax_support import *
+  from gyb_syntax_support.kinds import SYNTAX_BASE_KINDS
+  # -*- mode: Swift -*-
+  # Ignore the following admonition; it applies to the resulting .swift file only
+}%
+//// Automatically Generated From SyntaxBaseKinds.swift.gyb.
+//// Do Not Edit Directly!
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+let SYNTAX_BASE_KINDS: Set<String> = [
+% for name in SYNTAX_BASE_KINDS:
+  "${name}",
+% end
+]

Sources/SwiftSyntaxBuilderGeneration/SyntaxBuildableChild.swift

@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+/// Extension to the `Child` type to provide functionality specific to
+/// SwiftSyntaxBuilder.
+extension Child {
+  /// The type of this child, represented by a `SyntaxBuildableType`, which can
+  /// be used to create the corresponding `Buildable` and `ExpressibleAs` types.
+  var type: SyntaxBuildableType {
+    SyntaxBuildableType(
+      syntaxKind: syntaxKind,
+      isOptional: isOptional
+    )
+  }
+
+  /// If the child node has documentation associated with it, return it as single
+  /// line string. Otherwise return an empty string.
+  var documentation: String {
+    flattened(indentedDocumentation: description ?? "")
+  }
+
+  /// Generate a Swift expression that creates a proper SwiftSyntax node of type
+  /// `type.syntax` from a variable named `varName` of type `type.buildable` that
+  /// represents this child node.
+  func generateExprBuildSyntaxNode(varName: String, formatName: String) -> String {
+    if type.isToken {
+      if requiresLeadingNewline {
+        return "\(varName).withLeadingTrivia(.newline + \(formatName)._makeIndent() + (\(varName).leadingTrivia ?? []))"
+      } else {
+        return varName
+      }
+    } else {
+      let format = formatName + (isIndented ? "._indented()" : "")
+      let expr = "\(varName)\(type.optionalQuestionMark)"
+      return "\(expr).build\(type.baseName)(format: \(format), leadingTrivia: nil)"
+    }
+  }
+
+  /// If this node is a token that can't contain arbitrary text, generate a Swift
+  /// `assert` statement that verifies the variable with name var_name and of type
+  /// `TokenSyntax` contains one of the supported text options. Otherwise return `nil`.
+  func generateAssertStmtTextChoices(varName: String) -> String? {
+    guard type.isToken else {
+      return nil
+    }
+
+    let choices: [String]
+    if !textChoices.isEmpty {
+      choices = textChoices
+    } else if !tokenChoices.isEmpty {
+      let optionalChoices = tokenChoices.map { SYNTAX_TOKEN_MAP["\($0.name)Token"]?.text }
+      choices = optionalChoices.compactMap { $0 }
+      guard choices.count == optionalChoices.count else {
+        // If `nil` is in the text choices, one of the token options can contain arbitrary
+        // text. Don't generate an assert statement.
+        return nil
+      }
+    } else {
+      return nil
+    }
+
+    var assertChoices: [String] = []
+    if type.isOptional {
+      assertChoices.append("\(varName) == nil")
+    }
+    let unwrap = type.isOptional ? "!" : ""
+    for textChoice in choices {
+      assertChoices.append("\(varName)\(unwrap) == \"\(textChoice)\"")
+    }
+    return "assert(\(assertChoices.joined(separator: " || ")))"
+  }
+}

Sources/SwiftSyntaxBuilderGeneration/SyntaxBuildableNode.swift

@@ -0,0 +1,60 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+/// Extension to the `Node` type to provide functionality specific to
+/// SwiftSyntaxBuilder.
+extension Node {
+  /// The node's syntax kind as `SyntaxBuildableType`.
+  var type: SyntaxBuildableType {
+    SyntaxBuildableType(syntaxKind: syntaxKind)
+  }
+
+  /// The node's syntax kind as `SyntaxBuildableType`.
+  var baseType: SyntaxBuildableType {
+    SyntaxBuildableType(syntaxKind: baseKind)
+  }
+
+  /// If documentation exists for this node, return it as a single-line string.
+  /// Otherwise return an empty string.
+  var documentation: String {
+    guard let description = description,
+          !description.isEmpty else {
+      return ""
+    }
+    if isSyntaxCollection {
+      return "`\(syntaxKind)` represents a collection of `\(description)`"
+    } else {
+      return flattened(indentedDocumentation: description)
+    }
+  }
+
+  /// Assuming this node is a syntax collection, the type of its elements.
+  var collectionElementType: SyntaxBuildableType {
+    assert(isSyntaxCollection)
+    return SyntaxBuildableType(syntaxKind: collectionElement)
+  }
+
+  /// Assuming this node has a single child without a default value, that child.
+  var singleNonDefaultedChild: Child {
+    let nonDefaultedParams = children.filter(\.type.defaultInitialization.isEmpty)
+    assert(nonDefaultedParams.count == 1)
+    return nonDefaultedParams[0]
+  }
+
+  static func from(type: SyntaxBuildableType) -> Node {
+    let baseName = type.baseName
+    guard let node = SYNTAX_NODE_MAP[baseName] else {
+      fatalError("Base name \(baseName) does not have a syntax node")
+    }
+    return node
+  }
+}