Cherrypick recent changes into swift-5.2-branch.

Package.swift

@@ -22,7 +22,6 @@ let package = Package(
   ],
   dependencies: [
     .package(url: "https://github.com/apple/swift-syntax", from: "0.50200.0"),
-    .package(url: "https://github.com/apple/swift-tools-support-core.git", from: "0.0.1"),
     .package(url: "https://github.com/apple/swift-argument-parser.git", .upToNextMinor(from: "0.0.4")),
   ],
   targets: [
@@ -62,12 +61,11 @@ let package = Package(
     .target(
       name: "swift-format",
       dependencies: [
+        "ArgumentParser",
         "SwiftFormat",
         "SwiftFormatConfiguration",
         "SwiftFormatCore",
         "SwiftSyntax",
-        "SwiftToolsSupport-auto",
-        "ArgumentParser",
       ]
     ),
     .testTarget(

Sources/SwiftFormatPrettyPrint/TokenStreamCreator.swift

@@ -533,11 +533,19 @@ fileprivate final class TokenStreamCreator: SyntaxVisitor {
   override func visit(_ node: RepeatWhileStmtSyntax) -> SyntaxVisitorContinueKind {
     arrangeBracesAndContents(of: node.body, contentsKeyPath: \.statements)
 
-    let whilePrecedingBreak = config.lineBreakBeforeControlFlowKeywords
-      ? Token.break(.same) : Token.space
-    before(node.whileKeyword, tokens: whilePrecedingBreak)
+    if config.lineBreakBeforeControlFlowKeywords {
+      before(node.whileKeyword, tokens: .break(.same), .open)
+      after(node.condition.lastToken, tokens: .close)
+    } else {
+      // The length of the condition needs to force the breaks around the braces of the repeat
+      // stmt's body, so that there's always a break before the right brace when the while &
+      // condition is too long to be on one line.
+      before(node.whileKeyword, tokens: .space)
+      // The `open` token occurs after the ending tokens for the braced `body` node.
+      before(node.body.rightBrace, tokens: .open)
+      after(node.condition.lastToken, tokens: .close)
+    }
     after(node.whileKeyword, tokens: .space)
-
     return .visitChildren
   }
 

Sources/SwiftFormatRules/OrderedImports.swift

@@ -503,7 +503,7 @@ fileprivate class Line {
     else {
       return ""
     }
-    return importDecl.path.description.trimmingCharacters(in: .whitespaces)
+    return importDecl.path.description.trimmingCharacters(in: .whitespacesAndNewlines)
   }
 
   /// Returns the first `TokenSyntax` in the code block(s) from this Line, or nil when this Line

Sources/swift-format/Subcommands/DumpConfiguration.swift

@@ -13,8 +13,6 @@
 import ArgumentParser
 import Foundation
 import SwiftFormatConfiguration
-import TSCBasic
-import TSCUtility
 
 extension SwiftFormatCommand {
   /// Dumps the tool's default configuration in JSON format to standard output.

Sources/swift-format/Subcommands/Format.swift

@@ -15,7 +15,6 @@ import Foundation
 import SwiftFormat
 import SwiftFormatConfiguration
 import SwiftSyntax
-import TSCBasic
 
 extension SwiftFormatCommand {
   /// Formats one or more files containing Swift code.
@@ -89,31 +88,29 @@ private func formatMain(
   // fixed anyway.
   let formatter = SwiftFormatter(configuration: configuration, diagnosticEngine: nil)
   formatter.debugOptions = debugOptions
-  let assumingFileURL = URL(fileURLWithPath: assumingFilename ?? "<stdin>")
+
+  let path = assumingFilename ?? "<stdin>"
+  let assumingFileURL = URL(fileURLWithPath: path)
 
   guard let source = readSource(from: sourceFile) else {
     diagnosticEngine.diagnose(
-      Diagnostic.Message(
-        .error, "Unable to read source for formatting from \(assumingFileURL.path)."))
+      Diagnostic.Message(.error, "Unable to read source for formatting from \(path)."))
     return
   }
 
+  var stdoutStream = FileHandle.standardOutput
   do {
     if inPlace {
-      let cwd = FileManager.default.currentDirectoryPath
-      var buffer = BufferedOutputByteStream()
+      var buffer = ""
       try formatter.format(source: source, assumingFileURL: assumingFileURL, to: &buffer)
-      buffer.flush()
-      try localFileSystem.writeFileContents(
-        AbsolutePath(assumingFileURL.path, relativeTo: AbsolutePath(cwd)),
-        bytes: buffer.bytes
-      )
+
+      let bufferData = buffer.data(using: .utf8)!  // Conversion to UTF-8 cannot fail
+      try bufferData.write(to: assumingFileURL, options: .atomic)
     } else {
       try formatter.format(source: source, assumingFileURL: assumingFileURL, to: &stdoutStream)
-      stdoutStream.flush()
+      stdoutStream.synchronizeFile()
     }
   } catch SwiftFormatError.fileNotReadable {
-    let path = assumingFileURL.path
     diagnosticEngine.diagnose(
       Diagnostic.Message(
         .error, "Unable to format \(path): file is not readable or does not exist."))
@@ -125,17 +122,15 @@ private func formatMain(
         return
       }
       stdoutStream.write(source)
-      stdoutStream.flush()
+      stdoutStream.synchronizeFile()
       return
     }
-    let path = assumingFileURL.path
     let location = SourceLocationConverter(file: path, source: source).location(for: position)
     diagnosticEngine.diagnose(
       Diagnostic.Message(.error, "file contains invalid or unrecognized Swift syntax."),
       location: location)
     return
   } catch {
-    let path = assumingFileURL.path
     diagnosticEngine.diagnose(Diagnostic.Message(.error, "Unable to format \(path): \(error)"))
     return
   }

Sources/swift-format/Subcommands/LegacyMain.swift

@@ -16,7 +16,6 @@ import SwiftFormat
 import SwiftFormatConfiguration
 import SwiftFormatCore
 import SwiftSyntax
-import TSCBasic
 
 extension SwiftFormatCommand {
   /// Keep the legacy `-m/--mode` flag working temporarily when no other subcommand is specified.

Sources/swift-format/Subcommands/Lint.swift

@@ -15,7 +15,6 @@ import Foundation
 import SwiftFormat
 import SwiftFormatConfiguration
 import SwiftSyntax
-import TSCBasic
 
 extension SwiftFormatCommand {
   /// Emits style diagnostics for one or more files containing Swift code.

Sources/swift-format/Utilities/FileHandle+TextOutputStream.swift

@@ -0,0 +1,19 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2020 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
+//
+//===----------------------------------------------------------------------===//
+
+import Foundation
+
+extension FileHandle: TextOutputStream {
+  public func write(_ string: String) {
+    self.write(string.data(using: .utf8)!)  // Conversion to UTF-8 cannot fail
+  }
+}

Sources/swift-format/Utilities/Helpers.swift

@@ -16,7 +16,6 @@ import SwiftFormat
 import SwiftFormatConfiguration
 import SwiftFormatCore
 import SwiftSyntax
-import TSCBasic
 
 /// Throws an error that causes the current command to exit the process with a failure exit code if
 /// any of the preceding operations emitted diagnostics.

Tests/SwiftFormatPrettyPrintTests/DifferentiationAttributeTests.swift

@@ -43,8 +43,8 @@ final class DifferentiationAttributeTests: PrettyPrintTestCase {
     assertPrettyPrintEqual(input: input, expected: expected, linelength: 43)
   }
 
-  #if HAS_DERIVATIVE_REGISTRATION_ATTRIBUTE
-    func testDerivative() {
+  func testDerivative() {
+    #if HAS_DERIVATIVE_REGISTRATION_ATTRIBUTE
       let input =
         """
         @derivative(of: foo, wrt: x)
@@ -78,9 +78,11 @@ final class DifferentiationAttributeTests: PrettyPrintTestCase {
         """
 
       assertPrettyPrintEqual(input: input, expected: expected, linelength: 28)
-    }
+    #endif
+  }
 
-    func testTranspose() {
+  func testTranspose() {
+    #if HAS_DERIVATIVE_REGISTRATION_ATTRIBUTE
       let input =
         """
         @transpose(of: foo, wrt: 0)
@@ -114,6 +116,6 @@ final class DifferentiationAttributeTests: PrettyPrintTestCase {
         """
 
       assertPrettyPrintEqual(input: input, expected: expected, linelength: 27)
-    }
-  #endif
+    #endif
+  }
 }

Tests/SwiftFormatPrettyPrintTests/RepeatStmtTests.swift

@@ -10,6 +10,10 @@ final class RepeatStmtTests: PrettyPrintTestCase {
       while x
       repeat { foo() }
       while longcondition
+      repeat { f() }
+      while long.condition
+      repeat { f() } while long.condition
+      repeat { f() } while long.condition.that.ison.many.lines
       repeat {
         let a = 123
         var b = "abc"
@@ -29,6 +33,16 @@ final class RepeatStmtTests: PrettyPrintTestCase {
       repeat {
         foo()
       } while longcondition
+      repeat {
+        f()
+      } while long.condition
+      repeat {
+        f()
+      } while long.condition
+      repeat {
+        f()
+      } while long.condition
+        .that.ison.many.lines
       repeat {
         let a = 123
         var b = "abc"
@@ -50,6 +64,10 @@ final class RepeatStmtTests: PrettyPrintTestCase {
       repeat {} while x
       repeat { f() } while x
       repeat { foo() } while longcondition
+      repeat { f() }
+      while long.condition
+      repeat { f() } while long.condition
+      repeat { f() } while long.condition.that.ison.many.lines
       repeat {
         let a = 123
         var b = "abc"
@@ -68,6 +86,13 @@ final class RepeatStmtTests: PrettyPrintTestCase {
       repeat { f() } while x
       repeat { foo() }
       while longcondition
+      repeat { f() }
+      while long.condition
+      repeat { f() }
+      while long.condition
+      repeat { f() }
+      while long.condition.that
+        .ison.many.lines
       repeat {
         let a = 123
         var b = "abc"

Tests/SwiftFormatRulesTests/OrderedImportsTests.swift

@@ -396,6 +396,30 @@ final class OrderedImportsTests: LintOrFormatRuleTestCase {
     )
   }
 
+  func testImportsContainingNewlines() {
+    let input =
+      """
+      import
+        zeta
+      import Zeta
+      import
+        Alpha
+      import Beta
+      """
+
+    let expected =
+      """
+      import
+        Alpha
+      import Beta
+      import Zeta
+      import
+        zeta
+      """
+
+    XCTAssertFormatting(OrderedImports.self, input: input, expected: expected)
+  }
+
   func testRemovesDuplicateImports() {
     let input =
       """
@@ -541,4 +565,80 @@ final class OrderedImportsTests: LintOrFormatRuleTestCase {
 
     XCTAssertFormatting(OrderedImports.self, input: input, expected: expected)
   }
+
+  func testConditionalImports() {
+    let input =
+      """
+      import Zebras
+      import Apples
+      #if canImport(Darwin)
+        import Darwin
+      #elseif canImport(Glibc)
+        import Glibc
+      #endif
+      import Aardvarks
+
+      foo()
+      bar()
+      baz()
+      """
+
+    let expected =
+      """
+      import Aardvarks
+      import Apples
+      import Zebras
+
+      #if canImport(Darwin)
+        import Darwin
+      #elseif canImport(Glibc)
+        import Glibc
+      #endif
+
+      foo()
+      bar()
+      baz()
+      """
+
+    XCTAssertFormatting(OrderedImports.self, input: input, expected: expected)
+  }
+
+  func testIgnoredConditionalImports() {
+    let input =
+      """
+      import Zebras
+      import Apples
+      #if canImport(Darwin)
+        import Darwin
+      #elseif canImport(Glibc)
+        import Glibc
+      #endif
+      // swift-format-ignore
+      import Aardvarks
+
+      foo()
+      bar()
+      baz()
+      """
+
+    let expected =
+      """
+      import Apples
+      import Zebras
+
+      #if canImport(Darwin)
+        import Darwin
+      #elseif canImport(Glibc)
+        import Glibc
+      #endif
+      // swift-format-ignore
+      import Aardvarks
+
+      foo()
+      bar()
+      baz()
+      """
+
+    XCTAssertFormatting(OrderedImports.self, input: input, expected: expected)
+  }
 }