Support generic parameter wrapping.

Author: dabelknap

Sources/PrettyPrint/TokenStreamCreator.swift

@@ -282,8 +282,8 @@ private final class TokenStreamCreator: SyntaxVisitor {
   }
 
   override func visit(_ node: GenericParameterClauseSyntax) {
-    after(node.leftAngleBracket, tokens: .open(.consistent, 2), .break(size: 0))
-    before(node.rightAngleBracket, tokens: .break(size: 0), .close)
+    after(node.leftAngleBracket, tokens: .break(size: 0, offset: 2), .open(.consistent, 0))
+    before(node.rightAngleBracket, tokens: .break(size: 0, offset: -2), .close)
     super.visit(node)
   }
 
@@ -663,7 +663,9 @@ private final class TokenStreamCreator: SyntaxVisitor {
   }
 
   override func visit(_ node: GenericParameterSyntax) {
+    before(node.firstToken, tokens: .open)
     after(node.colon, tokens: .break)
+    after(node.lastToken, tokens: .close)
     super.visit(node)
   }
 

Tests/PrettyPrinterTests/FunctionDeclTests.swift

@@ -67,6 +67,10 @@ public class FunctionDeclTests: PrettyPrintTestCase {
     func myFun<S, T>(var1: S, var2: T) {
       print("Hello World")
     }
+
+    func longerNameFun<ReallyLongTypeName: Conform, TypeName>(var1: ReallyLongTypeNAme, var2: TypeName) {
+      let a = 123
+    }
     """
 
     let expected =
@@ -75,6 +79,16 @@ public class FunctionDeclTests: PrettyPrintTestCase {
       print("Hello World")
     }
 
+    func longerNameFun<
+      ReallyLongTypeName: Conform,
+      TypeName
+    >(
+      var1: ReallyLongTypeNAme,
+      var2: TypeName
+    ) {
+      let a = 123
+    }
+
     """
 
     assertPrettyPrintEqual(input: input, expected: expected, linelength: 40)