Remove code that only its tests used

A mechanism with tests but no production callers is not covered. It is a
well-tested spare part, and its green tests actively disguise that
nothing reaches it — the same blind spot that hid three wiring bugs
earlier in this branch.

Removing the eight such mechanisms in live code drops 42 tests:

- URBTracker, a dead duplicate. UNLINK cancels through
  USBSubmitProcessor.cancelURB, which does its own tracking.
- DeviceMonitor, 192 lines. Hotplug is handled directly by the
  deviceDiscovery callbacks ServerCoordinator installs.
- The logDebug/logInfo/logWarning/logError/logCritical globals, an
  unused parallel API next to 739 uses of the logger methods. Their one
  test asserted nothing beyond "does not crash".
- USBErrorMapping.mapUSBStatusToIOKit, the reverse of the direction the
  server actually needs.
- The static USBErrorMapping.errorDescription(for:).
- ServerConfig.resetToDefaults.
- CompletionFormattingUtilities.formatDescription, and
  generateFallbackCompletion, which was also stale: it advertised attach
  and detach, removed from the CLI earlier.

The instance errorDescription was kept. It shares a name with the
deleted static but is LocalizedError conformance, reached through
localizedDescription rather than a call site — a sweep keyed on call
sites cannot see protocol dispatch, so hits need checking against
conformances before deletion.

383 tests pass, lint clean, and the control transfer against a J-Link
still returns its real descriptor.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017rmyikdjWveP99ZUCDLY89

Author: beriberikix

Documentation/development/unwired-code-sweep.md

@@ -28,14 +28,34 @@ failed. Fixed, with four tests over the mapping.
 `USBRequestHandler.init`, it was dead. Leaving it would have preserved the exact trap
 that caused the original bug: a setter that looks like the wiring point and is not.
 
+## Removed: mechanisms with tests but no production callers
+
+Deleting these removed 42 tests. That is the point — they were green tests over code
+the daemon never reached, and their passing actively disguised that nothing used it.
+
+| Removed | Why it was safe |
+| --- | --- |
+| `URBTracker` and its ~30 tests | a dead duplicate; UNLINK cancels through `USBSubmitProcessor.cancelURB`, which tracks URBs in `activeURBs` |
+| `DeviceMonitor` (192 lines) and its tests | hotplug is handled directly by `deviceDiscovery.onDeviceConnected`/`onDeviceDisconnected` in `ServerCoordinator` |
+| `logDebug`/`logInfo`/`logWarning`/`logError`/`logCritical` globals | an unused parallel API; production uses the `logger.debug(…)` methods in 739 places. Their one test asserted nothing beyond "does not crash" |
+| `USBErrorMapping.mapUSBStatusToIOKit` | the reverse direction. The server maps IOKit → USB/IP via `mapIOKitError`, which is live |
+| `USBErrorMapping.errorDescription(for:)` (static) | no callers. The *instance* `errorDescription` is `LocalizedError` conformance and was kept |
+| `ServerConfig.resetToDefaults` | no callers |
+| `CompletionFormattingUtilities.formatDescription` | no callers |
+| `CompletionFormattingUtilities.generateFallbackCompletion` | no callers, and stale: it advertised `attach` and `detach`, removed from the CLI |
+
+One near-miss worth recording: the sweep flagged `errorDescription`, but the instance
+property of that name is a `LocalizedError` requirement reached through
+`localizedDescription`. A sweep keyed on call sites cannot see protocol dispatch, so
+every hit needs checking against the conformance list before deletion. Only the static
+overload was genuinely unused.
+
 ## Confirmed unwired, not yet addressed
 
 | Thing | State | Consequence |
 | --- | --- | --- |
 | `USBIPMessageValidator.validateUSBIPMessage` | zero callers, production *and* test | the buffer-size bound it contains is never applied |
 | `USBIPMessageValidator.validateSetupPacket` | zero callers | setup packets reach IOKit unvalidated |
-| `URBTracker` (`addPendingURB`, `removeCompletedURB`, `getPendingURB`, `getAllPendingSeqnums`, `clearAllPendingURBs`) | constructed once in `USBRequestHandler`, never called | a dead duplicate; the live tracking is `USBSubmitProcessor.activeURBs`. ~30 tests cover the unused copy |
-| `DeviceMonitor` | never constructed in production | `isActive`/`getKnownDevices` are tested against a class the daemon does not use |
 | `config.maxConnections` | only copied config→config by the `config` command | connection count is unbounded |
 | `config.connectionTimeout` | same | idle connections are never reaped |
 | `config.autoBindDevices` | same | setting it does nothing |
@@ -73,7 +93,11 @@ Most remaining zero-caller hits are inside the quarantined System Extension subs
 and are expected — that code is inert by design. The signal is confined to
 `USBIPDCore` outside `SystemExtension/`, `USBIPDCLI`, and `Common`.
 
-The `TESTS-ONLY` category deserves the same suspicion as `DEAD`. A mechanism with
-tests but no production callers is not covered — it is a well-tested spare part, and
-its green tests actively obscure that nothing uses it. `URBTracker` is the clearest
-case in this repository.
+The `TESTS-ONLY` category deserved the same suspicion as `DEAD`, and is now empty for
+live code. A mechanism with tests but no production callers is not covered — it is a
+well-tested spare part whose green tests obscure that nothing uses it.
+
+Re-running the sweep is the cheap way to keep it that way. What remains is confined to
+the quarantined System Extension subsystem, which is inert by design, and to the
+`config.*` and validator rows above, which are unwired behaviour rather than unused
+code and need decisions rather than deletions.

Sources/Common/Logger.swift

@@ -287,72 +287,3 @@ public final class Logger {
         return components.joined(separator: " ")
     }
 }
-
-// MARK: - Global Convenience Functions
-
-/// Global debug logging function
-public func logDebug(
-    _ message: String,
-    context: [String: Any] = [:],
-    file: String = #file,
-    function: String = #function,
-    line: Int = #line
-) {
-    Logger.shared.debug(message, context: context, file: file, function: function, line: line)
-}
-
-/// Global info logging function
-public func logInfo(
-    _ message: String,
-    context: [String: Any] = [:],
-    file: String = #file,
-    function: String = #function,
-    line: Int = #line
-) {
-    Logger.shared.info(message, context: context, file: file, function: function, line: line)
-}
-
-/// Global warning logging function
-public func logWarning(
-    _ message: String,
-    context: [String: Any] = [:],
-    file: String = #file,
-    function: String = #function,
-    line: Int = #line
-) {
-    Logger.shared.warning(message, context: context, file: file, function: function, line: line)
-}
-
-/// Global error logging function
-public func logError(
-    _ message: String,
-    context: [String: Any] = [:],
-    file: String = #file,
-    function: String = #function,
-    line: Int = #line
-) {
-    Logger.shared.error(message, context: context, file: file, function: function, line: line)
-}
-
-/// Global critical logging function
-public func logCritical(
-    _ message: String,
-    context: [String: Any] = [:],
-    file: String = #file,
-    function: String = #function,
-    line: Int = #line
-) {
-    Logger.shared.critical(message, context: context, file: file, function: function, line: line)
-}
-
-/// Global error logging function for Error objects
-public func logError(
-    _ error: Error,
-    message: String? = nil,
-    context: [String: Any] = [:],
-    file: String = #file,
-    function: String = #function,
-    line: Int = #line
-) {
-    Logger.shared.error(error, message: message, context: context, file: file, function: function, line: line)
-}

Sources/USBIPDCore/CLI/ShellCompletionFormatter.swift

@@ -93,29 +93,6 @@ public enum CompletionFormattingUtilities {
         }
     }
 
-    /// Format a description string for shell completion
-    /// - Parameters:
-    ///   - description: The description to format
-    ///   - shellType: Target shell type
-    /// - Returns: Formatted description suitable for the shell
-    public static func formatDescription(_ description: String, for shellType: String) -> String {
-        let escaped = escapeForShell(description, shellType: shellType)
-        
-        switch shellType {
-        case "zsh":
-            // Zsh supports rich descriptions in square brackets
-            return "[\(escaped)]"
-        case "fish":
-            // Fish uses -d flag for descriptions
-            return escaped
-        case "bash":
-            // Bash completion typically doesn't show descriptions
-            return escaped
-        default:
-            return escaped
-        }
-    }
-    
     /// Generate a list of command names for completion
     /// - Parameter commands: Array of commands
     /// - Returns: Space-separated list of command names
@@ -230,57 +207,4 @@ public enum CompletionFormattingUtilities {
 
         return issues
     }
-    
-    /// Generate a fallback completion for unsupported scenarios
-    /// - Parameters:
-    ///   - shellType: Target shell type
-    ///   - commandName: Name of the command
-    /// - Returns: Basic fallback completion script
-    public static func generateFallbackCompletion(for shellType: String, commandName: String) -> String {
-        switch shellType {
-        case "bash":
-            return """
-            # Fallback bash completion for \(commandName)
-            complete -W "help list bind unbind attach detach daemon install-system-extension diagnose" \(commandName)
-            """
-            
-        case "zsh":
-            return """
-            #compdef \(commandName)
-            # Fallback zsh completion for \(commandName)
-            _\(commandName)() {
-                local commands=(
-                    'help:Display help information'
-                    'list:List available USB devices'
-                    'bind:Bind a USB device to USB/IP'
-                    'unbind:Unbind a USB device from USB/IP'
-                    'attach:Attach a remote USB device'
-                    'detach:Detach a remote USB device'
-                    'daemon:Start USB/IP daemon'
-                    'install-system-extension:Install and register the System Extension'
-                    'diagnose:Run comprehensive installation and system diagnostics'
-                )
-                _describe 'commands' commands
-            }
-            _\(commandName) "$@"
-            """
-            
-        case "fish":
-            return """
-            # Fallback fish completion for \(commandName)
-            complete -c \(commandName) -n '__fish_use_subcommand' -a 'help' -d 'Display help information'
-            complete -c \(commandName) -n '__fish_use_subcommand' -a 'list' -d 'List available USB devices'
-            complete -c \(commandName) -n '__fish_use_subcommand' -a 'bind' -d 'Bind a USB device to USB/IP'
-            complete -c \(commandName) -n '__fish_use_subcommand' -a 'unbind' -d 'Unbind a USB device from USB/IP'
-            complete -c \(commandName) -n '__fish_use_subcommand' -a 'attach' -d 'Attach a remote USB device'
-            complete -c \(commandName) -n '__fish_use_subcommand' -a 'detach' -d 'Detach a remote USB device'
-            complete -c \(commandName) -n '__fish_use_subcommand' -a 'daemon' -d 'Start USB/IP daemon'
-            complete -c \(commandName) -n '__fish_use_subcommand' -a 'install-system-extension' -d 'Install and register the System Extension'
-            complete -c \(commandName) -n '__fish_use_subcommand' -a 'diagnose' -d 'Run comprehensive installation and system diagnostics'
-            """
-            
-        default:
-            return "# Unsupported shell type: \(shellType)"
-        }
-    }
 }