SwiftPM6: Fix to skip locking package build directory

Sources/DependencyCalculator/DependencyGraph.swift

@@ -6,6 +6,7 @@ import Foundation
 import Git
 import PathKit
 import SelectiveTestLogger
+import SelectiveTestShell
 import Workspace
 import XcodeProj
 
@@ -200,8 +201,14 @@ extension WorkspaceInfo {
             } == nil
         }
 
+        // SwiftPM6 locks build directory up when parsing multiple packages concurrently
+        let isSwiftVersion6Plus = try isSwiftVersion6Plus()
+
         return Array(allPackages).concurrentMap { path in
-            try? PackageTargetMetadata.parse(at: path.parent())
+            try? PackageTargetMetadata.parse(
+                at: path.parent(),
+                addingIgnoreLockOption: isSwiftVersion6Plus
+            )
         }.compactMap { $0 }.reduce([PackageTargetMetadata]()) { partialResult, new in
             var result = partialResult
             result.append(contentsOf: new)
@@ -347,4 +354,22 @@ extension WorkspaceInfo {
                              dependencyStructure: DependencyGraph(dependsOn: dependsOn),
                              candidateTestPlan: candidateTestPlan)
     }
+
+    private static func isSwiftVersion6Plus() throws -> Bool {
+        guard let regex = try? NSRegularExpression(pattern: #"Apple Swift version (\d+)"#) else {
+            return false
+        }
+
+        let versionString = try Shell.execOrFail("swift --version")
+        let range = NSRange(versionString.startIndex..<versionString.endIndex, in: versionString)
+        if let match = regex.firstMatch(in: versionString, options: [], range: range),
+           let majorVersionRange = Range(match.range(at: 1), in: versionString),
+           let majorVersion = Int(versionString[majorVersionRange]),
+           majorVersion > 5
+        {
+            return true
+        } else {
+            return false
+        }
+    }
 }

Sources/DependencyCalculator/PackageMetadata.swift

@@ -16,9 +16,17 @@ struct PackageTargetMetadata {
     let testTarget: Bool
 
     // TODO: Split in several methods
-    static func parse(at path: Path) throws -> [PackageTargetMetadata] {
-        // NB: Flag `--disable-sandbox` is required to allow running SPM from an SPM plugin
-        let manifest = try Shell.execOrFail("cd \(path) && swift package dump-package --disable-sandbox").trimmingCharacters(in: .newlines)
+    static func parse(at path: Path, addingIgnoreLockOption: Bool = false) throws -> [PackageTargetMetadata] {
+        // NB:
+        //  - Flag `--disable-sandbox` is required to allow running SPM from an SPM plugin
+        //  - Flag `--ignore-lock` is required to avoid locking the package build directory when parsing is done concurrently (Swift 6).
+        var flags = ["--disable-sandbox"]
+        if addingIgnoreLockOption {
+            flags.append("--ignore-lock")
+        }
+
+        let manifest = try Shell.execOrFail("cd \(path) && swift package dump-package \(flags.joined(separator: " "))")
+            .trimmingCharacters(in: .newlines)
         guard let manifestData = manifest.data(using: .utf8),
               let manifestJson = try JSONSerialization.jsonObject(with: manifestData, options: []) as? [String: Any],
               let targets = manifestJson["targets"] as? [[String: Any]]