Address code review comments and fix some trivia issues

Author: DougGregor

Sources/PackageModelSyntax/AddPackageDependency.swift

@@ -96,8 +96,7 @@ public struct AddPackageDependency {
                             trailingComma: .commaToken()
                         )
                     ],
-                    rightSquare: .rightSquareToken()
-                        .with(\.leadingTrivia, leadingTrivia)
+                    rightSquare: .rightSquareToken(leadingTrivia: leadingTrivia)
                 )
                 newArgument = ExprSyntax(arrayExpr)
             }

Sources/PackageModelSyntax/SyntaxEditUtils.swift

@@ -22,13 +22,7 @@ let defaultIndent = TriviaPiece.spaces(4)
 extension Trivia {
     /// Determine whether this trivia has newlines or not.
     var hasNewlines: Bool {
-        contains { piece in
-            if case .newlines = piece {
-                return true
-            } else {
-                return false
-            }
-        }
+        contains(where: \.isNewline)
     }
 }
 
@@ -121,7 +115,7 @@ extension LabeledExprListSyntax {
 
         let positionIdx = distance(from: startIndex, to: position)
 
-        let commaToken = TokenSyntax(.comma, presence: .present)
+        let commaToken = TokenSyntax.commaToken()
 
         // Figure out leading trivia and adjust the prior argument (if there is
         // one) by adding a comma, if necessary.
@@ -177,7 +171,7 @@ extension ArrayExprSyntax {
     ) -> ArrayExprSyntax {
         var elements = self.elements
 
-        let commaToken = TokenSyntax(.comma, presence: .present)
+        let commaToken = TokenSyntax.commaToken()
 
         // If there are already elements, tack it on.
         let leadingTrivia: Trivia
@@ -192,7 +186,10 @@ extension ArrayExprSyntax {
             // there.
             if last.trailingComma == nil {
                 var newElements = Array(elements)
-                newElements[newElements.count-1] = last.with(\.trailingComma, commaToken)
+                newElements[newElements.count - 1].trailingComma = commaToken
+                newElements[newElements.count - 1].expression.trailingTrivia =
+                    Trivia()
+                newElements[newElements.count - 1].trailingTrivia = last.trailingTrivia
                 elements = ArrayElementListSyntax(newElements)
             }
 

Tests/PackageModelSyntaxTests/ManifestEditTests.swift

@@ -147,6 +147,35 @@ class ManifestEditTests: XCTestCase {
         }
     }
 
+    func testAddPackageDependencyExistingOneLine() throws {
+        try assertManifestRefactor("""
+            // swift-tools-version: 5.5
+            let package = Package(
+                name: "packages",
+                dependencies: [ .package(url: "https://github.com/apple/swift-syntax.git", from: "510.0.1") ]
+            )
+            """, expectedManifest: """
+            // swift-tools-version: 5.5
+            let package = Package(
+                name: "packages",
+                dependencies: [ .package(url: "https://github.com/apple/swift-syntax.git", from: "510.0.1"), .package(url: "https://github.com/apple/swift-system.git", from: "510.0.0"),]
+            )
+            """) { manifest in
+                let versionRange = Range<Version>.upToNextMajor(from: Version(510, 0, 0))
+
+                return try AddPackageDependency.addPackageDependency(
+                    PackageDependency.remoteSourceControl(
+                        identity: PackageIdentity(url: Self.swiftSystemURL),
+                        nameForTargetDependencyResolutionOnly: nil,
+                        url: Self.swiftSystemURL,
+                        requirement: .range(versionRange),
+                        productFilter: .nothing
+                    ),
+                    to: manifest,
+                    manifestDirectory: try! AbsolutePath(validating: "/")
+                )
+        }
+    }
     func testAddPackageDependencyExistingEmpty() throws {
         try assertManifestRefactor("""
             // swift-tools-version: 5.5