[xcodegen] Avoid tracking inferArgs per target/source

This is unnecessary since we never configure it
per target, just check the global setting.

utils/swift-xcodegen/Sources/SwiftXcodeGen/Generator/ClangTarget.swift

@@ -13,13 +13,13 @@
 struct ClangTarget {
   var name: String
   var parentPath: RelativePath
-  var sources: [Source]
-  var unbuildableSources: [Source]
+  var sources: [RelativePath]
+  var unbuildableSources: [RelativePath]
   var headers: [RelativePath]
 
   init(
     name: String, parentPath: RelativePath,
-    sources: [Source], unbuildableSources: [Source] = [],
+    sources: [RelativePath], unbuildableSources: [RelativePath] = [],
     headers: [RelativePath]
   ) {
     self.name = name
@@ -30,13 +30,6 @@ struct ClangTarget {
   }
 }
 
-extension ClangTarget {
-  struct Source {
-    var path: RelativePath
-    var inferArgs: Bool
-  }
-}
-
 extension RepoBuildDir {
   func getCSourceFilePaths(for path: RelativePath) throws -> [RelativePath] {
     try getAllRepoSubpaths(of: path).filter(\.isCSourceLike)
@@ -58,24 +51,15 @@ extension RepoBuildDir {
       return nil
     }
 
-    var sources: [ClangTarget.Source] = []
-    var unbuildableSources: [ClangTarget.Source] = []
+    var sources: [RelativePath] = []
+    var unbuildableSources: [RelativePath] = []
     for path in sourcePaths {
-      let source: ClangTarget.Source? =
-        if try clangArgs.hasBuildArgs(for: path) {
-          .init(path: path, inferArgs: false)
-        } else if target.inferArgs {
-          .init(path: path, inferArgs: true)
-        } else {
-          nil
-        }
-      guard let source else { continue }
-
-      // If we're inferring arguments, or have a known unbuildable, treat as not
+      // If we have no arguments, or have a known unbuildable, treat as not
       // buildable. We'll still include it in the project, but in a separate
       // target that isn't built by default.
-      if source.inferArgs || knownUnbuildables.contains(path) {
-        unbuildableSources.append(source)
+      if try !clangArgs.hasBuildArgs(for: path) ||
+          knownUnbuildables.contains(path) {
+        unbuildableSources.append(path)
         continue
       }
       // If we have no '.o' present for a given file, assume it's not buildable.
@@ -84,10 +68,10 @@ extension RepoBuildDir {
       if target.mayHaveUnbuildableFiles,
           try !clangArgs.isObjectFilePresent(for: path) {
         log.debug("! Treating '\(path)' as unbuildable; no '.o' file")
-        unbuildableSources.append(source)
+        unbuildableSources.append(path)
         continue
       }
-      sources.append(source)
+      sources.append(path)
     }
 
     return ClangTarget(

utils/swift-xcodegen/Sources/SwiftXcodeGen/Generator/ClangTargetSource.swift

@@ -15,16 +15,13 @@ struct ClangTargetSource {
   var name: String
   var path: RelativePath
   var mayHaveUnbuildableFiles: Bool
-  var inferArgs: Bool
 
   init(
     at path: RelativePath, named name: String,
-    mayHaveUnbuildableFiles: Bool,
-    inferArgs: Bool
+    mayHaveUnbuildableFiles: Bool
   ) {
     self.name = name
     self.path = path
     self.mayHaveUnbuildableFiles = mayHaveUnbuildableFiles
-    self.inferArgs = inferArgs
   }
 }

utils/swift-xcodegen/Sources/SwiftXcodeGen/Generator/ProjectGenerator.swift

@@ -34,7 +34,7 @@ fileprivate final class ProjectGenerator {
   private var groups: [RelativePath: CachedGroup] = [:]
   private var files: [RelativePath: Xcode.FileReference] = [:]
   private var targets: [String: Xcode.Target] = [:]
-  private var unbuildableSources: [ClangTarget.Source] = []
+  private var unbuildableSources: [RelativePath] = []
   private var runnableBuildTargets: [RunnableTarget: Xcode.Target] = [:]
 
   /// The group in which external files are stored.
@@ -321,12 +321,11 @@ fileprivate final class ProjectGenerator {
       return false
     }
     let parent = clangTarget.parentPath
-    let sources = clangTarget.sources.map(\.path)
-    let hasConsistentArgs = try sources.allSatisfy {
+    let hasConsistentArgs = try clangTarget.sources.allSatisfy {
       try !buildDir.clangArgs.hasUniqueArgs(for: $0, parent: parent)
     }
     guard hasConsistentArgs else { return false }
-    return try canUseBuildableFolder(at: parent, sources: sources)
+    return try canUseBuildableFolder(at: parent, sources: clangTarget.sources)
   }
 
   func canUseBuildableFolder(
@@ -394,15 +393,14 @@ fileprivate final class ProjectGenerator {
     let sourcesToBuild = target.addSourcesBuildPhase()
 
     for source in targetInfo.sources {
-      let sourcePath = source.path
-      guard let sourceRef = getOrCreateRepoRef(.file(sourcePath)) else {
+      guard let sourceRef = getOrCreateRepoRef(.file(source)) else {
         continue
       }
       let buildFile = sourcesToBuild.addBuildFile(fileRef: sourceRef)
 
       // Add any per-file settings.
       var fileArgs = try buildDir.clangArgs.getUniqueArgs(
-        for: sourcePath, parent: targetPath, infer: source.inferArgs
+        for: source, parent: targetPath, infer: spec.inferArgs
       )
       if !fileArgs.isEmpty {
         applyBaseSubstitutions(to: &fileArgs)

utils/swift-xcodegen/Sources/SwiftXcodeGen/Generator/ProjectSpec.swift

@@ -206,9 +206,7 @@ extension ProjectSpec {
     guard let path = mapPath(path, for: "Clang target") else { return }
     let name = name ?? path.fileName
     clangTargetSources.append(ClangTargetSource(
-      at: path, named: name,
-      mayHaveUnbuildableFiles: mayHaveUnbuildableFiles,
-      inferArgs: inferArgs
+      at: path, named: name, mayHaveUnbuildableFiles: mayHaveUnbuildableFiles
     ))
   }