Check the output of wasm in dev subcommand test

Sources/CartonFrontend/Commands/CartonFrontendDevCommand.swift

@@ -162,7 +162,11 @@ struct CartonFrontendDevCommand: AsyncParsableCommand {
     )
     let localURL = try await server.start()
     if !skipAutoOpen {
-      openInSystemBrowser(url: localURL)
+      do {
+        try openInSystemBrowser(url: localURL)
+      } catch {
+        terminal.write("open browser failed: \(error)", inColor: .red)
+      }
     }
     try await server.waitUntilStop()
   }

Sources/CartonFrontend/Commands/TestRunners/BrowserTestRunner.swift

@@ -178,7 +178,7 @@ struct BrowserTestRunner: TestRunner {
         try await client.goto(url: localURL)
       } else {
         disposer = {}
-        openInSystemBrowser(url: localURL)
+        try openInSystemBrowser(url: localURL)
       }
       let hadError = try await server.waitUntilTestFinished()
       try await disposer()

Sources/CartonKit/Server/Server.swift

@@ -69,6 +69,18 @@ public protocol BuilderProtocol {
 }
 
 public actor Server {
+  public enum Error: Swift.Error & CustomStringConvertible {
+    case invalidURL(String)
+    case noOpenBrowserPlatform
+
+    public var description: String {
+      switch self {
+      case .invalidURL(let string): "Invalid URL: \(string)"
+      case .noOpenBrowserPlatform: "This platform cannot launch a browser."
+      }
+    }
+  }
+
   final class Connection: Hashable {
     let channel: Channel
 
@@ -105,8 +117,8 @@ public actor Server {
 
   private var serverChannel: (any Channel)!
 
-  /// Local URL of this server, `https://128.0.0.1:8080/` by default.
-  private let localURL: String
+  /// Local URL of this server, `https://127.0.0.1:8080/` by default.
+  private let localURL: URL
 
   /// Whether a build that could be triggered by this server is currently running.
   private var isBuildCurrentlyRunning = false
@@ -156,7 +168,11 @@ public actor Server {
   public init(
     _ configuration: Configuration
   ) async throws {
-    localURL = "http://\(configuration.host):\(configuration.port)/"
+    let localURLString = "http://\(configuration.host):\(configuration.port)/"
+    guard let localURL = URL(string: localURLString) else {
+      throw Error.invalidURL(localURLString)
+    }
+    self.localURL = localURL
     watcher = nil
     self.configuration = configuration
 
@@ -222,7 +238,7 @@ public actor Server {
     connections.remove(connection)
   }
 
-  public func start() async throws -> String {
+  public func start() async throws -> URL {
     let group = MultiThreadedEventLoopGroup.singleton
     let upgrader = NIOWebSocketServerUpgrader(
       maxFrameSize: Int(UInt32.max),
@@ -421,25 +437,18 @@ extension Server {
 }
 
 /// Attempts to open the specified URL string in system browser on macOS and Linux.
-/// - Returns: true if launching command returns successfully.
-@discardableResult
-public func openInSystemBrowser(url: String) -> Bool {
+public func openInSystemBrowser(url: URL) throws {
   #if os(macOS)
     let openCommand = "open"
   #elseif os(Linux)
     let openCommand = "xdg-open"
   #else
-    return false
+    throw Server.Error.noOpenBrowserPlatform
   #endif
   let process = Process(
-    arguments: [openCommand, url],
+    arguments: [openCommand, url.absoluteString],
     outputRedirection: .none,
     startNewProcessGroup: true
   )
-  do {
-    try process.launch()
-    return true
-  } catch {
-    return false
-  }
+  try process.launch()
 }

Sources/WebDriverClient/WebDriverClient.swift

@@ -110,13 +110,13 @@ public struct WebDriverClient {
     return try encoder.encode(body)
   }
 
-  public func goto(url: String) async throws {
+  public func goto(url: URL) async throws {
     struct Request: Encodable {
       let url: String
     }
     var request = URLRequest(url: URL(string: makeSessionURL("url"))!)
     request.httpMethod = "POST"
-    request.httpBody = try Self.makeRequestBody(Request(url: url))
+    request.httpBody = try Self.makeRequestBody(Request(url: url.absoluteString))
     request.addValue("carton", forHTTPHeaderField: "User-Agent")
     _ = try await client.data(for: request)
   }

Tests/CartonCommandTests/FrontendDevServerTests.swift

@@ -29,13 +29,31 @@ final class FrontendDevServerTests: XCTestCase {
 
     try await Process.run(["swift", "build", "--target", "carton-frontend"], terminal)
 
+    var gotHelloStdout = false
+    var gotHelloStderr = false
+
     let devServer = Process(
       arguments: [
         "swift", "run", "carton-frontend", "dev",
         "--skip-auto-open", "--verbose",
         "--main-wasm-path", wasmFile.pathString,
         "--resources", resourcesDir.pathString
-      ]
+      ],
+      outputRedirection: .stream(
+        stdout: { (chunk) in
+          let string = String(decoding: chunk, as: UTF8.self)
+
+          if string.contains("stdout: hello stdout") {
+            gotHelloStdout = true
+          }
+          if string.contains("stderr: hello stderr") {
+            gotHelloStderr = true
+          }
+
+          terminal.write(string)
+        }, stderr: { (_) in },
+        redirectStderr: true
+      )
     )
     try devServer.launch()
     defer {
@@ -84,6 +102,16 @@ final class FrontendDevServerTests: XCTestCase {
       let expected = try String(contentsOf: resourcesDir.appending(component: name).asURL)
       XCTAssertEqual(styleCss, expected)
     }
+
+    try openInSystemBrowser(url: host)
+
+    for _ in 0..<30 {
+      try await Task.sleep(for: .seconds(1))
+      if gotHelloStdout, gotHelloStderr { break }
+    }
+
+    XCTAssertTrue(gotHelloStdout)
+    XCTAssertTrue(gotHelloStderr)
   }
 
   private func fetchBinary(

Tests/WebDriverClientTests/WebDriverClientTests.swift

@@ -27,7 +27,7 @@ final class WebDriverClientTests: XCTestCase {
     let client = try await WebDriverClient.newSession(
       endpoint: checkRemoteURL(), httpClient: .shared
     )
-    try await client.goto(url: "https://example.com")
+    try await client.goto(url: URL(string: "https://github.com/swiftwasm/carton")!)
     try await client.closeSession()
   }
 }