Merge into single subcommand

Author: andre-richter

README.md

@@ -219,10 +219,10 @@ description of the configuration format and the settings that are available.
 
 #### Viewing the Effective Configuration
 
-The `dump-effective-configuration` subcommand dumps the configuration that
-would be used if `swift-format` was executed from the current working directory,
-and accounts for `.swift-format` files or `--configuration` options as outlined
-above.
+The `dump-configuration` subcommand accepts a `--effective` flag. If set, it
+dumps the configuration that would be used if `swift-format` was executed from
+the current working directory, and accounts for `.swift-format` files or
+ `--configuration` options as outlined above.
 
 ### Miscellaneous
 

Sources/swift-format/CMakeLists.txt

@@ -12,13 +12,12 @@ add_executable(swift-format
   SwiftFormatCommand.swift
   VersionOptions.swift
   Frontend/ConfigurationLoader.swift
-  Frontend/DumpEffectiveConfigurationFrontend.swift
+  Frontend/DumpConfigurationFrontend.swift
   Frontend/FormatFrontend.swift
   Frontend/Frontend.swift
   Frontend/LintFrontend.swift
   Subcommands/ConfigurationOptions.swift
   Subcommands/DumpConfiguration.swift
-  Subcommands/DumpEffectiveConfiguration.swift
   Subcommands/Format.swift
   Subcommands/Lint.swift
   Subcommands/LintFormatOptions.swift

…DumpEffectiveConfigurationFrontend.swift …Frontend/DumpConfigurationFrontend.swiftSources/swift-format/Frontend/DumpEffectiveConfigurationFrontend.swift renamed to Sources/swift-format/Frontend/DumpConfigurationFrontend.swift Sources/swift-format/Frontend/DumpEffectiveConfigurationFrontend.swift renamed to Sources/swift-format/Frontend/DumpConfigurationFrontend.swift

@@ -13,13 +13,13 @@
 import Foundation
 import SwiftFormat
 
-/// The frontend for dumping the effective configuration.
-class DumpEffectiveConfigurationFrontend: Frontend {
-  private(set) var dumpResult: Result<String, Error> = .failure(
-    SwiftFormatError.configurationDumpFailed("Configuration not resolved yet")
+/// The frontend for dumping the configuration.
+class DumpConfigurationFrontend: Frontend {
+  private(set) var dumpedConfiguration: Result<String, Error> = .failure(
+    SwiftFormatError.configurationDumpFailed("Configuration not dumped yet")
   )
 
   override func processFile(_ fileToProcess: FileToProcess) {
-    dumpResult = Result.init(catching: fileToProcess.configuration.asJsonString)
+    dumpedConfiguration = Result.init(catching: fileToProcess.configuration.asJsonString)
   }
 }

Sources/swift-format/Subcommands/ConfigurationOptions.swift

@@ -12,7 +12,7 @@
 
 import ArgumentParser
 
-/// Common arguments used by the `lint`, `format` and `dump-effective-configuration` subcommands.
+/// Common arguments used by the `lint`, `format` and `dump-configuration` subcommands.
 struct ConfigurationOptions: ParsableArguments {
   /// The path to the JSON configuration file that should be loaded.
   ///

Sources/swift-format/Subcommands/DumpConfiguration.swift

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2025 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
@@ -15,16 +15,56 @@ import Foundation
 import SwiftFormat
 
 extension SwiftFormatCommand {
-  /// Dumps the tool's default configuration in JSON format to standard output.
+  /// Dumps the tool's configuration in JSON format to standard output.
   struct DumpConfiguration: ParsableCommand {
     static var configuration = CommandConfiguration(
-      abstract: "Dump the default configuration in JSON format to standard output"
+      abstract: "Dump the configuration in JSON format to standard output",
+      discussion: """
+        Without any options, dumps the default configuration. When '--effective' is set, dumps the configuration that \
+        would be used if swift-format was executed from the current working directory (cwd), incorporating \
+        configuration files found in the cwd or its parents, or input from the '--configuration' option.
+        """
     )
 
+    /// Whether or not to dump the effective configuration.
+    @Flag(name: .shortAndLong, help: "Dump the effective instead of the default configuration.")
+    var effective: Bool = false
+
+    @OptionGroup()
+    var configurationOptions: ConfigurationOptions
+
+    func validate() throws {
+      if configurationOptions.configuration != nil && !effective {
+        throw ValidationError("'--configuration' is only valid in combination with '--effective'")
+      }
+    }
+
     func run() throws {
-      let configuration = try Configuration().asJsonString()
+      if !effective {
+        let configuration = try Configuration().asJsonString()
+        print(configuration)
+        return
+      }
+
+      // Pretend to use stdin, so that the configuration loading machinery in the Frontend base class can be used in the
+      // next step. This produces the same results as if "format" or "lint" subcommands were called.
+      let lintFormatOptions = try LintFormatOptions.parse(["-"])
+
+      let frontend = DumpConfigurationFrontend(
+        configurationOptions: configurationOptions,
+        lintFormatOptions: lintFormatOptions
+      )
+      frontend.run()
+      if frontend.diagnosticsEngine.hasErrors {
+        throw ExitCode.failure
+      }
 
-      print(configuration)
+      switch frontend.dumpedConfiguration {
+      case .success(let configuration):
+        print(configuration)
+      case .failure(let error):
+        throw error
+      }
     }
   }
 }

Sources/swift-format/Subcommands/DumpEffectiveConfiguration.swift

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2025 Apple Inc. and the Swift project authors
+// 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
@@ -21,7 +21,6 @@ struct SwiftFormatCommand: ParsableCommand {
     abstract: "Format or lint Swift source code",
     subcommands: [
       DumpConfiguration.self,
-      DumpEffectiveConfiguration.self,
       Format.self,
       Lint.self,
     ],