Add string conformances to Attachable; write attachments to system/user temporary directory by default

Author: grynspan

Sources/Testing/ABI/EntryPoints/EntryPoint.swift

@@ -479,6 +479,9 @@ public func configurationForEntryPoint(from args: __CommandLineArguments_v0) thr
       throw _EntryPointError.invalidArgument("--experimental-attachment-path", value: attachmentPath)
     }
     configuration.attachmentDirectoryPath = attachmentPath
+  } else {
+    // Write attachments to the system's temporary directory.
+    configuration.attachmentDirectoryPath = try temporaryDirectoryPath()
   }
 
 #if canImport(Foundation)

Sources/Testing/Attachments/Test.Attachable.swift

@@ -70,3 +70,23 @@ extension UnsafeRawBufferPointer: Test.Attachable {
     try body(self)
   }
 }
+
+@_spi(Experimental)
+extension String: Test.Attachable {
+  public func withUnsafeBufferPointer<R>(for attachment: borrowing Test.Attachment, _ body: (UnsafeRawBufferPointer) throws -> R) throws -> R {
+    var selfCopy = self
+    return try selfCopy.withUTF8 { utf8 in
+      try body(UnsafeRawBufferPointer(utf8))
+    }
+  }
+}
+
+@_spi(Experimental)
+extension Substring: Test.Attachable {
+  public func withUnsafeBufferPointer<R>(for attachment: borrowing Test.Attachment, _ body: (UnsafeRawBufferPointer) throws -> R) throws -> R {
+    var selfCopy = self
+    return try selfCopy.withUTF8 { utf8 in
+      try body(UnsafeRawBufferPointer(utf8))
+    }
+  }
+}

Sources/Testing/Support/FileHandle.swift

@@ -632,4 +632,33 @@ func canonicalizePath(_ path: String) -> String? {
   return nil
 #endif
 }
+
+/// Get the path to the user's or system's temporary directory.
+///
+/// - Returns: The path to a directory suitable for storing temporary files.
+///
+/// - Throws: If the user's or system's temporary directory could not be
+///   determined.
+func temporaryDirectoryPath() throws -> String {
+#if SWT_TARGET_OS_APPLE
+  try withUnsafeTemporaryAllocation(of: CChar.self, capacity: Int(PATH_MAX)) { buffer in
+    if 0 != confstr(_CS_DARWIN_USER_TEMP_DIR, buffer.baseAddress, buffer.count) {
+      return String(cString: buffer.baseAddress!)
+    }
+    return try #require(Environment.variable(named: "TMPDIR"))
+  }
+#elseif os(Linux) || os(FreeBSD)
+  "/tmp"
+#elseif os(Android)
+  Environment.variable(named: "TMPDIR") ?? "/data/local/tmp"
+#elseif os(Windows)
+  try withUnsafeTemporaryAllocation(of: wchar_t.self, capacity: Int(MAX_PATH + 1)) { buffer in
+    // NOTE: GetTempPath2W() was introduced in Windows 10 Build 20348.
+    if 0 == GetTempPathW(DWORD(buffer.count), buffer.baseAddress) {
+      throw Win32Error(rawValue: GetLastError())
+    }
+    return try #require(String.decodeCString(buffer.baseAddress, as: UTF16.self)?.result)
+  }
+#endif
+}
 #endif

Tests/TestingTests/AttachmentTests.swift

@@ -24,7 +24,7 @@ struct AttachmentTests {
     let attachment = Test.Attachment(attachableValue, named: "loremipsum.html")
 
     // Write the attachment to disk, then read it back.
-    let filePath = try attachment.write(toFileInDirectoryAtPath: temporaryDirectory())
+    let filePath = try attachment.write(toFileInDirectoryAtPath: temporaryDirectoryPath())
     defer {
       remove(filePath)
     }
@@ -59,7 +59,7 @@ struct AttachmentTests {
       let attachment = Test.Attachment(attachableValue, named: baseFileName)
 
       // Write the attachment to disk, then read it back.
-      let filePath = try attachment.write(toFileInDirectoryAtPath: temporaryDirectory(), appending: suffixes.next()!)
+      let filePath = try attachment.write(toFileInDirectoryAtPath: temporaryDirectoryPath(), appending: suffixes.next()!)
       createdFilePaths.append(filePath)
       let fileName = try #require(filePath.split { $0 == "/" || $0 == #"\"# }.last)
       if i == 0 {
@@ -85,14 +85,14 @@ struct AttachmentTests {
 
     // Write the attachment to disk once to ensure the original filename is not
     // available and we add a suffix.
-    let originalFilePath = try attachment.write(toFileInDirectoryAtPath: temporaryDirectory())
+    let originalFilePath = try attachment.write(toFileInDirectoryAtPath: temporaryDirectoryPath())
     defer {
       remove(originalFilePath)
     }
 
     // Write the attachment to disk, then read it back.
     let suffix = String(UInt64.random(in: 0 ..< .max), radix: 36)
-    let filePath = try attachment.write(toFileInDirectoryAtPath: temporaryDirectory(), appending: suffix)
+    let filePath = try attachment.write(toFileInDirectoryAtPath: temporaryDirectoryPath(), appending: suffix)
     defer {
       remove(filePath)
     }

Tests/TestingTests/Support/FileHandleTests.swift

@@ -215,7 +215,7 @@ func withTemporaryPath<R>(_ body: (_ path: String) throws -> R) throws -> R {
     return strnlen(buffer.baseAddress!, buffer.count)
   }
 #else
-  let path = appendPathComponent("file_named_\(UInt64.random(in: 0 ..< .max))", to: try temporaryDirectory())
+  let path = appendPathComponent("file_named_\(UInt64.random(in: 0 ..< .max))", to: try temporaryDirectoryPath())
 #endif
   defer {
     _ = remove(path)
@@ -247,29 +247,6 @@ extension FileHandle {
 }
 #endif
 
-func temporaryDirectory() throws -> String {
-#if SWT_TARGET_OS_APPLE
-  try withUnsafeTemporaryAllocation(of: CChar.self, capacity: Int(PATH_MAX)) { buffer in
-    if 0 != confstr(_CS_DARWIN_USER_TEMP_DIR, buffer.baseAddress, buffer.count) {
-      return String(cString: buffer.baseAddress!)
-    }
-    return try #require(Environment.variable(named: "TMPDIR"))
-  }
-#elseif os(Linux) || os(FreeBSD)
-  "/tmp"
-#elseif os(Android)
-  Environment.variable(named: "TMPDIR") ?? "/data/local/tmp"
-#elseif os(Windows)
-  try withUnsafeTemporaryAllocation(of: wchar_t.self, capacity: Int(MAX_PATH + 1)) { buffer in
-    // NOTE: GetTempPath2W() was introduced in Windows 10 Build 20348.
-    if 0 == GetTempPathW(DWORD(buffer.count), buffer.baseAddress) {
-      throw Win32Error(rawValue: GetLastError())
-    }
-    return try #require(String.decodeCString(buffer.baseAddress, as: UTF16.self)?.result)
-  }
-#endif
-}
-
 #if SWT_TARGET_OS_APPLE
 func fileHandleForCloseMonitoring(with confirmation: Confirmation) throws -> FileHandle {
   let context = Unmanaged.passRetained(confirmation as AnyObject).toOpaque()

Tests/TestingTests/SwiftPMTests.swift

@@ -176,7 +176,7 @@ struct SwiftPMTests {
   func xunitOutputIsWrittenToFile() throws {
     // Test that a file is opened when requested. Testing of the actual output
     // occurs in ConsoleOutputRecorderTests.
-    let tempDirPath = try temporaryDirectory()
+    let tempDirPath = try temporaryDirectoryPath()
     let temporaryFilePath = appendPathComponent("\(UInt64.random(in: 0 ..< .max))", to: tempDirPath)
     defer {
       _ = remove(temporaryFilePath)
@@ -200,7 +200,7 @@ struct SwiftPMTests {
     "--configuration-path", "--experimental-configuration-path",
   ])
   func configurationPath(argumentName: String) async throws {
-    let tempDirPath = try temporaryDirectory()
+    let tempDirPath = try temporaryDirectoryPath()
     let temporaryFilePath = appendPathComponent("\(UInt64.random(in: 0 ..< .max))", to: tempDirPath)
     defer {
       _ = remove(temporaryFilePath)
@@ -244,7 +244,7 @@ struct SwiftPMTests {
   func eventStreamOutput(outputArgumentName: String, versionArgumentName: String, version: String) async throws {
     // Test that JSON records are successfully streamed to a file and can be
     // read back into memory and decoded.
-    let tempDirPath = try temporaryDirectory()
+    let tempDirPath = try temporaryDirectoryPath()
     let temporaryFilePath = appendPathComponent("\(UInt64.random(in: 0 ..< .max))", to: tempDirPath)
     defer {
       _ = remove(temporaryFilePath)

Tests/TestingTests/Traits/TagListTests.swift

@@ -121,7 +121,7 @@ struct TagListTests {
 #if !SWT_NO_FILE_IO
   @Test("Colors are read from disk")
   func tagColorsReadFromDisk() throws {
-    let tempDirPath = try temporaryDirectory()
+    let tempDirPath = try temporaryDirectoryPath()
     let jsonPath = appendPathComponent("tag-colors.json", to: tempDirPath)
     var jsonContent = """
     {