Merge pull request swiftlang#127 from dabelknap/protocols

Support protocol declarations

Author: allevato

Sources/PrettyPrint/TokenStreamCreator.swift

@@ -363,6 +363,23 @@ private final class TokenStreamCreator: SyntaxVisitor {
     super.visit(node)
   }
 
+  override func visit(_ node: AccessorDeclSyntax) {
+    super.visit(node)
+  }
+
+  override func visit(_ node: AccessorBlockSyntax) {
+    after(node.leftBrace, tokens: .break(offset: 2), .open(.consistent, 0))
+    before(node.rightBrace, tokens: .break(offset: -2), .close)
+    super.visit(node)
+  }
+
+  override func visit(_ node: AccessorListSyntax) {
+    if node.count > 1 {
+      after(node.first?.lastToken, tokens: .break)
+    }
+    super.visit(node)
+  }
+
   func shouldAddOpenCloseNewlines(_ node: Syntax) -> Bool {
     if node is AccessorListSyntax { return true }
     guard let list = node as? CodeBlockItemListSyntax else {
@@ -372,10 +389,6 @@ private final class TokenStreamCreator: SyntaxVisitor {
     return FindChildScope().findChildScope(in: list)
   }
 
-  override func visit(_ node: AccessorBlockSyntax) {
-    super.visit(node)
-  }
-
   override func visit(_ node: CodeBlockSyntax) {
     for i in 0..<(node.statements.count - 1) {
       after(node.statements[i].lastToken, tokens: .newline)
@@ -704,10 +717,6 @@ private final class TokenStreamCreator: SyntaxVisitor {
     super.visit(node)
   }
 
-  override func visit(_ node: AccessorDeclSyntax) {
-    super.visit(node)
-  }
-
   override func visit(_ node: ArrayElementSyntax) {
     before(node.firstToken, tokens: .open)
     if let trailingComma = node.trailingComma {
@@ -768,6 +777,21 @@ private final class TokenStreamCreator: SyntaxVisitor {
   }
 
   override func visit(_ node: ProtocolDeclSyntax) {
+    if let attributes = node.attributes {
+      before(node.firstToken, tokens: .space(size: 0), .open(.consistent, 0))
+      after(attributes.lastToken, tokens: .open)
+    } else {
+      before(node.firstToken, tokens: .space(size: 0), .open(.consistent, 0), .open)
+    }
+
+    after(node.protocolKeyword, tokens: .break)
+    before(node.members.leftBrace, tokens: .break)
+    after(
+      node.members.leftBrace,
+      tokens: .close, .close, .break(size: 0, offset: 2), .open(.consistent, 0)
+    )
+    before(node.members.rightBrace, tokens: .break(size: 0, offset: -2), .close)
+
     super.visit(node)
   }
 
@@ -880,6 +904,7 @@ private final class TokenStreamCreator: SyntaxVisitor {
   }
 
   override func visit(_ node: PatternBindingSyntax) {
+    before(node.accessor?.firstToken, tokens: .break)
     super.visit(node)
   }
 

Tests/PrettyPrinterTests/ProtocolDeclTests.swift

@@ -0,0 +1,144 @@
+public class ProtocolDeclTests: PrettyPrintTestCase {
+  public func testBasicProtocolDeclarations() {
+    let input =
+      """
+      protocol MyProtocol {
+        var A: Int { get set }
+        var B: Bool { get }
+      }
+      protocol MyProtocol {
+        var VeryLongVariable: Int { get set }
+        var B: Bool { get }
+      }
+      public protocol MyProtocol {
+        var A: Int { get set }
+        var B: Bool { get }
+      }
+      public protocol MyLongerProtocol {
+        var A: Int { get set }
+        var B: Bool { get }
+      }
+      """
+
+    let expected =
+      """
+      protocol MyProtocol {
+        var A: Int { get set }
+        var B: Bool { get }
+      }
+      protocol MyProtocol {
+        var VeryLongVariable: Int {
+          get
+          set
+        }
+        var B: Bool { get }
+      }
+      public protocol MyProtocol {
+        var A: Int { get set }
+        var B: Bool { get }
+      }
+      public protocol
+      MyLongerProtocol {
+        var A: Int { get set }
+        var B: Bool { get }
+      }
+
+      """
+
+    assertPrettyPrintEqual(input: input, expected: expected, linelength: 30)
+  }
+
+  public func testProtocolInheritence() {
+    let input =
+      """
+      protocol MyProtocol: ProtoOne {
+        var A: Int { get set }
+        var B: Bool { get }
+      }
+      protocol MyProtocol: ProtoOne, ProtoTwo {
+        var A: Int { get set }
+        var B: Bool { get }
+      }
+      protocol MyProtocol: ProtoOne, ProtoTwo, ProtoThree {
+        var A: Int { get set }
+        var B: Bool { get }
+      }
+      """
+
+    let expected =
+      """
+      protocol MyProtocol: ProtoOne {
+        var A: Int { get set }
+        var B: Bool { get }
+      }
+      protocol MyProtocol: ProtoOne, ProtoTwo {
+        var A: Int { get set }
+        var B: Bool { get }
+      }
+      protocol MyProtocol:
+        ProtoOne,
+        ProtoTwo,
+        ProtoThree
+      {
+        var A: Int { get set }
+        var B: Bool { get }
+      }
+
+      """
+
+    assertPrettyPrintEqual(input: input, expected: expected, linelength: 50)
+  }
+
+
+  public func testProtocolAttributes() {
+    let input =
+      """
+      @dynamicMemberLookup public protocol MyProtocol {
+        var A: Int { get set }
+        var B: Double { get }
+      }
+      @dynamicMemberLookup @objc public protocol MyProtocol {
+        var A: Int { get set }
+        var B: Double { get }
+      }
+      @dynamicMemberLookup @objc @objcMembers public protocol MyProtocol {
+        var A: Int { get set }
+        var B: Double { get }
+      }
+      @dynamicMemberLookup
+      @available(swift 4.0)
+      public protocol MyProtocol {
+        var A: Int { get set }
+        var B: Double { get }
+      }
+      """
+
+    let expected =
+      """
+      @dynamicMemberLookup public protocol MyProtocol {
+        var A: Int { get set }
+        var B: Double { get }
+      }
+      @dynamicMemberLookup @objc public protocol MyProtocol {
+        var A: Int { get set }
+        var B: Double { get }
+      }
+      @dynamicMemberLookup
+      @objc
+      @objcMembers
+      public protocol MyProtocol {
+        var A: Int { get set }
+        var B: Double { get }
+      }
+      @dynamicMemberLookup
+      @available(swift 4.0)
+      public protocol MyProtocol {
+        var A: Int { get set }
+        var B: Double { get }
+      }
+
+      """
+
+    assertPrettyPrintEqual(input: input, expected: expected, linelength: 60)
+  }
+}