Specify host name in PreviewServer.Bind.localhost

`ServerBootstrap.bind` needs to know which host name to bind a socket
to, but we were hardcoding it to `localhost` without providing a way for
a different host to be provided. By adding a `host:` element to
`PreviewServer.Bind.localhost`, we require the caller of
`PreviewServer.init` to be specific about which host they want.

Author: tomstuart

Sources/SwiftDocCUtilities/Action/Actions/PreviewAction.swift

@@ -173,7 +173,7 @@ public final class PreviewAction: Action, RecreatingContext {
                 print(String(repeating: "=", count: 40), to: &logHandle)
             }
 
-            let to: PreviewServer.Bind = bindServerToSocketPath.map { .socket(path: $0) } ?? .localhost(port: port)
+            let to: PreviewServer.Bind = bindServerToSocketPath.map { .socket(path: $0) } ?? .localhost(host: "localhost", port: port)
             servers[serverIdentifier] = try PreviewServer(contentURL: convertAction.targetDirectory, bindTo: to, logHandle: &logHandle)
 
             // When the user stops docc - stop the preview server first before exiting.

Sources/SwiftDocCUtilities/PreviewServer/PreviewServer.swift

@@ -72,15 +72,15 @@ final class PreviewServer {
     /// A list of server-bind destinations.
     public enum Bind: CustomStringConvertible {
         /// A port on the local machine.
-        case localhost(port: Int)
+        case localhost(host: String, port: Int)
 
         /// A file socket on disk.
         case socket(path: String)
 
         var description: String {
             switch self {
-            case .localhost(port: let port):
-                return "localhost:\(port)"
+            case .localhost(host: let host, port: let port):
+                return "\(host):\(port)"
             case .socket(path: let path):
                 return path
             }
@@ -146,21 +146,21 @@ final class PreviewServer {
         do {
             // Bind to the given destination
             switch bindTo {
-            case .localhost(let port):
-                channel = try bootstrap.bind(host: "localhost", port: port).wait()
+            case .localhost(let host, let port):
+                channel = try bootstrap.bind(host: host, port: port).wait()
             case .socket(let path):
                 channel = try bootstrap.bind(unixDomainSocketPath: path).wait()
             }
         } catch let error as NIO.IOError where error.errnoCode == EADDRINUSE {
             // The given port is not available.
             switch bindTo {
-                case .localhost(let port): throw Error.portNotAvailable(port: port)
+                case .localhost(_, let port): throw Error.portNotAvailable(port: port)
                 default: throw error
             }
         } catch {
             // Cannot bind the given address/port.
             switch bindTo {
-                case .localhost(let port): throw Error.cannotStartServer(port: port)
+                case .localhost(_, let port): throw Error.cannotStartServer(port: port)
                 default: throw error
             }
         }

Tests/SwiftDocCUtilitiesTests/PreviewServer/PreviewServerTests.swift

@@ -201,7 +201,7 @@ class PreviewServerTests {
     }
 
     func testPreviewServerBindDescription() {
-        let localhostBind = PreviewServer.Bind.localhost(port: 1234)
+        let localhostBind = PreviewServer.Bind.localhost(host: "localhost", port: 1234)
         XCTAssertEqual("\(localhostBind)", "localhost:1234")
         let socketBind = PreviewServer.Bind.socket(path: "/tmp/file.sock")
         XCTAssertEqual("\(socketBind)", "/tmp/file.sock")