Refactor compose file flag into shared OptionGroup for up, down, and build.

Sources/Container-Compose/Commands/ComposeDown.swift

@@ -43,8 +43,8 @@ public struct ComposeDown: AsyncParsableCommand {
 
     private var cwd: String { process.cwd ?? FileManager.default.currentDirectoryPath }
 
-    @Option(name: [.customShort("f"), .customLong("file")], help: "The path to your Docker Compose file")
-    var composeFilename: String?
+    @OptionGroup
+    var composeFileOptions: ComposeFileOptions
 
     private static let supportedComposeFilenames = [
         "compose.yml",
@@ -58,7 +58,7 @@ public struct ComposeDown: AsyncParsableCommand {
     }
 
     private var composePath: String {
-        if let composeFilename {
+        if let composeFilename = composeFileOptions.composeFilename {
             return resolvedPath(for: composeFilename, relativeTo: cwdURL)
         }
 

Sources/Container-Compose/Commands/ComposeFileOptions.swift

@@ -0,0 +1,22 @@
+//===----------------------------------------------------------------------===//
+// Copyright © 2025 Morris Richman and the Container-Compose project authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//   https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//===----------------------------------------------------------------------===//
+
+import ArgumentParser
+
+public struct ComposeFileOptions: ParsableArguments, Sendable {
+    @Option(name: [.customShort("f"), .customLong("file")], help: "The path to your Docker Compose file")
+    public var composeFilename: String?
+}

Sources/Container-Compose/Commands/ComposeUp.swift

@@ -46,8 +46,8 @@ public struct ComposeUp: AsyncParsableCommand, @unchecked Sendable {
         help: "Detaches from container logs. Note: If you do NOT detach, killing this process will NOT kill the container. To kill the container, run container-compose down")
     var detach: Bool = false
 
-    @Option(name: [.customShort("f"), .customLong("file")], help: "The path to your Docker Compose file")
-    var composeFilename: String?
+    @OptionGroup
+    var composeFileOptions: ComposeFileOptions
 
     private static let supportedComposeFilenames = [
         "compose.yml",
@@ -61,7 +61,7 @@ public struct ComposeUp: AsyncParsableCommand, @unchecked Sendable {
     }
 
     private var composePath: String {
-        if let composeFilename {
+        if let composeFilename = composeFileOptions.composeFilename {
             return resolvedPath(for: composeFilename, relativeTo: cwdURL)
         }
 
@@ -524,7 +524,7 @@ public struct ComposeUp: AsyncParsableCommand, @unchecked Sendable {
                 runCommandArgs.append(networkToConnect)
             }
             print(
-                "Info: Service '\(serviceName)' is configured to connect to networks: \(serviceNetworks.joined(separator: ", ")) ascertained from networks attribute in \(composeFilename)."
+                "Info: Service '\(serviceName)' is configured to connect to networks: \(serviceNetworks.joined(separator: ", ")) ascertained from networks attribute in \(composePath)."
             )
             print(
                 "Note: This tool assumes custom networks are defined at the top-level 'networks' key or are pre-existing. This tool does not create implicit networks for services if not explicitly defined at the top-level."

Tests/Container-Compose-StaticTests/ComposeCommandParsingTests.swift

@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+// Copyright © 2025 Morris Richman and the Container-Compose project authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//   https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//===----------------------------------------------------------------------===//
+
+import Testing
+@testable import ContainerComposeCore
+
+@Suite("Compose command parsing")
+struct ComposeCommandParsingTests {
+    @Test("ComposeUp command accepts -f flag for compose file")
+    func composeUpCommandAcceptsFileFlag() throws {
+        let cmd = try ComposeUp.parse(["-f", "my-compose.yaml"])
+        #expect(cmd.composeFileOptions.composeFilename == "my-compose.yaml")
+    }
+
+    @Test("ComposeDown command accepts -f flag for compose file")
+    func composeDownCommandAcceptsFileFlag() throws {
+        let cmd = try ComposeDown.parse(["-f", "my-compose.yaml"])
+        #expect(cmd.composeFileOptions.composeFilename == "my-compose.yaml")
+    }
+}