BridgeJS: Add additionalSourceDirs config for cross-plugin file discovery

Author: krodak

Plugins/BridgeJS/Sources/BridgeJSBuildPlugin/BridgeJSBuildPlugin.swift

@@ -32,6 +32,11 @@ struct BridgeJSBuildPlugin: BuildToolPlugin {
             inputFiles.append(configFile)
         }
 
+        let additionalDirs = resolveAdditionalSourceDirs(targetDirectory: target.directoryURL)
+        for dir in additionalDirs {
+            inputFiles.append(contentsOf: recursivelyCollectSwiftFiles(from: dir))
+        }
+
         let inputTSFile = target.directoryURL.appending(path: "bridge-js.d.ts")
         let tsconfigPath = context.package.directoryURL.appending(path: "tsconfig.json")
 
@@ -47,7 +52,6 @@ struct BridgeJSBuildPlugin: BuildToolPlugin {
         ]
 
         if FileManager.default.fileExists(atPath: inputTSFile.path) {
-            // Add .d.ts file and tsconfig.json as inputs
             inputFiles.append(contentsOf: [inputTSFile, tsconfigPath])
             arguments.append(contentsOf: [
                 "--project",
@@ -66,4 +70,56 @@ struct BridgeJSBuildPlugin: BuildToolPlugin {
         )
     }
 }
+
+private struct PluginConfig: Decodable {
+    var additionalSourceDirs: [String]?
+}
+
+private func resolveAdditionalSourceDirs(targetDirectory: URL) -> [URL] {
+    let configFiles = [
+        targetDirectory.appending(path: "bridge-js.config.json"),
+        targetDirectory.appending(path: "bridge-js.config.local.json"),
+    ]
+    var dirs: [String] = []
+    for file in configFiles {
+        guard FileManager.default.fileExists(atPath: file.path),
+            let data = try? Data(contentsOf: file),
+            let config = try? JSONDecoder().decode(PluginConfig.self, from: data),
+            let additional = config.additionalSourceDirs
+        else { continue }
+        dirs.append(contentsOf: additional)
+    }
+    return dirs.compactMap { dir in
+        let resolved = targetDirectory.appending(path: dir).standardized
+        var isDirectory: ObjCBool = false
+        guard FileManager.default.fileExists(atPath: resolved.path, isDirectory: &isDirectory),
+            isDirectory.boolValue
+        else {
+            return nil
+        }
+        return resolved
+    }
+}
+
+private func recursivelyCollectSwiftFiles(from directory: URL) -> [URL] {
+    var swiftFiles: [URL] = []
+    guard
+        let enumerator = FileManager.default.enumerator(
+            at: directory,
+            includingPropertiesForKeys: [.isRegularFileKey],
+            options: [.skipsHiddenFiles]
+        )
+    else {
+        return []
+    }
+    for case let fileURL as URL in enumerator {
+        if fileURL.pathExtension == "swift" {
+            let resourceValues = try? fileURL.resourceValues(forKeys: [.isRegularFileKey])
+            if resourceValues?.isRegularFile == true {
+                swiftFiles.append(fileURL)
+            }
+        }
+    }
+    return swiftFiles.sorted { $0.path < $1.path }
+}
 #endif

Plugins/BridgeJS/Sources/BridgeJSCore/Misc.swift

@@ -309,6 +309,7 @@ public struct BridgeJSCoreError: Swift.Error, CustomStringConvertible {
 
 import struct Foundation.URL
 import struct Foundation.Data
+import struct Foundation.ObjCBool
 import class Foundation.FileManager
 import class Foundation.JSONDecoder
 
@@ -328,20 +329,33 @@ public struct BridgeJSConfig: Codable {
     /// Default: `false`
     public var exposeToGlobal: Bool
 
-    public init(tools: [String: String]? = nil, exposeToGlobal: Bool = false) {
+    /// Additional directories containing Swift source files to scan for
+    /// `@JS` annotations.
+    ///
+    /// Paths are resolved relative to the target directory. This is useful
+    /// when Swift files with `@JS` annotations are generated by another
+    /// build plugin whose outputs aren't included in `target.sourceFiles`.
+    ///
+    /// Default: `nil` (no additional directories)
+    public var additionalSourceDirs: [String]?
+
+    public init(tools: [String: String]? = nil, exposeToGlobal: Bool = false, additionalSourceDirs: [String]? = nil) {
         self.tools = tools
         self.exposeToGlobal = exposeToGlobal
+        self.additionalSourceDirs = additionalSourceDirs
     }
 
     enum CodingKeys: String, CodingKey {
         case tools
         case exposeToGlobal
+        case additionalSourceDirs
     }
 
     public init(from decoder: Decoder) throws {
         let container = try decoder.container(keyedBy: CodingKeys.self)
         tools = try container.decodeIfPresent([String: String].self, forKey: .tools)
         exposeToGlobal = try container.decodeIfPresent(Bool.self, forKey: .exposeToGlobal) ?? false
+        additionalSourceDirs = try container.decodeIfPresent([String].self, forKey: .additionalSourceDirs)
     }
 
     /// Load the configuration file from the SwiftPM package target directory.
@@ -380,11 +394,36 @@ public struct BridgeJSConfig: Codable {
         return try JSONDecoder().decode(BridgeJSConfig.self, from: data)
     }
 
+    /// Resolve additional source directories relative to a base URL.
+    ///
+    /// Returns absolute URLs for each configured additional source directory.
+    /// Directories that don't exist are silently skipped.
+    public func resolveAdditionalSourceDirs(relativeTo baseURL: URL) -> [URL] {
+        guard let dirs = additionalSourceDirs else { return [] }
+        return dirs.compactMap { dir in
+            let resolved = baseURL.appending(path: dir).standardized
+            var isDirectory: ObjCBool = false
+            guard FileManager.default.fileExists(atPath: resolved.path, isDirectory: &isDirectory),
+                isDirectory.boolValue
+            else {
+                return nil
+            }
+            return resolved
+        }
+    }
+
     /// Merge the current configuration with the overrides.
     func merging(overrides: BridgeJSConfig) -> BridgeJSConfig {
+        let mergedDirs: [String]? = {
+            let base = self.additionalSourceDirs ?? []
+            let extra = overrides.additionalSourceDirs ?? []
+            let combined = base + extra
+            return combined.isEmpty ? nil : combined
+        }()
         return BridgeJSConfig(
             tools: (tools ?? [:]).merging(overrides.tools ?? [:], uniquingKeysWith: { $1 }),
-            exposeToGlobal: overrides.exposeToGlobal
+            exposeToGlobal: overrides.exposeToGlobal,
+            additionalSourceDirs: mergedDirs
         )
     }
 }

Plugins/BridgeJS/Sources/BridgeJSTool/BridgeJSTool.swift

@@ -146,6 +146,17 @@ import BridgeJSUtilities
             var inputFiles = withSpan("Collecting Swift files") {
                 return inputSwiftFiles(targetDirectory: targetDirectory, positionalArguments: positionalArguments)
             }
+
+            let additionalDirs = config.resolveAdditionalSourceDirs(relativeTo: targetDirectory)
+            for dir in additionalDirs {
+                let additionalFiles = recursivelyCollectSwiftFiles(from: dir).map(\.path)
+                    .filter { !inputFiles.contains($0) }
+                if !additionalFiles.isEmpty {
+                    progress.print("Found \(additionalFiles.count) additional Swift files in \(dir.lastPathComponent)")
+                }
+                inputFiles.append(contentsOf: additionalFiles)
+            }
+
             // BridgeJS.Macros.swift contains imported declarations (@JSFunction, @JSClass, etc.) that need
             // to be processed by SwiftToSkeleton to populate the imported skeleton. The command plugin
             // filters out Generated/ files, so we explicitly add it here after generation.