Merge pull request swiftlang#76 from nkcsgexi/accessor-as-modifier

API: child syntax should be able to be modified by using accessors

Author: nkcsgexi

Sources/SwiftSyntax/SyntaxNodes.swift.gyb

@@ -101,6 +101,7 @@ public struct ${node.name}: ${base_type}, _SyntaxBase, Hashable {
  /// ${line}
 % end
  public var ${child.swift_name}: ${ret_type} {
+ get {
  let child = data.child(at: Cursor.${child.swift_name}, parent: self)
 % if child.is_optional:
  if child == nil { return nil }
@@ -115,6 +116,10 @@ public struct ${node.name}: ${base_type}, _SyntaxBase, Hashable {
  return makeSyntax(child!) ${cast}
 % end
  }
+ set(value) {
+ self = with${child.name}(value)
+ }
+ }
 % if child_node and child_node.is_syntax_collection():
 % child_elt = child_node.collection_element_name
 % child_elt_type = child_node.collection_element_type

Tests/LinuxMain.swift

@@ -14,6 +14,7 @@ XCTMain({ () -> [XCTestCaseEntry] in
  testCase(SyntaxAPITestCase.allTests),
  testCase(SyntaxVisitorTestCase.allTests),
  testCase(TokenSyntaxTestCase.allTests),
+ testCase(SyntaxTreeModifierTests.allTests),
  ]
  return testCases
 }())

Tests/SwiftSyntaxTest/ModifierTests.swift

@@ -0,0 +1,30 @@
+import XCTest
+import SwiftSyntax
+
+fileprivate func cannedVarDecl() -> VariableDeclSyntax {
+ let Pattern = SyntaxFactory.makePatternBinding(
+ pattern: SyntaxFactory.makeIdentifierPattern(
+ identifier: SyntaxFactory.makeIdentifier("a").withLeadingTrivia(.spaces(1))),
+ typeAnnotation: SyntaxFactory.makeTypeAnnotation(
+ colon: SyntaxFactory.makeColonToken().withTrailingTrivia(.spaces(1)),
+ type: SyntaxFactory.makeTypeIdentifier("Int")),
+ initializer: nil, accessor: nil, trailingComma: nil)
+ return VariableDeclSyntax {
+ $0.useLetOrVarKeyword(SyntaxFactory.makeLetKeyword())
+ $0.addPatternBinding(Pattern)
+ }
+}
+
+public class SyntaxTreeModifierTests: XCTestCase {
+
+ public static let allTests = [
+ ("testAccessorAsModifier", testAccessorAsModifier)
+ ]
+
+ public func testAccessorAsModifier() {
+ var VD = cannedVarDecl()
+ XCTAssertEqual("\(VD)", "let a: Int")
+ VD.letOrVarKeyword = SyntaxFactory.makeVarKeyword().withTrailingTrivia(.spaces(0))
+ XCTAssertEqual("\(VD)", "var a: Int")
+ }
+}