some updates - test requires correctly setting SWIFTPM_CUSTOM_BIN_DIR env var to have IntegrationTets pass

Author: bkhouri

Package.swift

@@ -798,6 +798,7 @@ let package = Package(
             /** SwiftPM internal test suite support library */
             name: "_IntegrationTestSupport",
             dependencies: [
+                "_InternalTestSupport",
                 .product(name: "TSCTestSupport", package: "swift-tools-support-core"),
             ]
         ),
@@ -1005,6 +1006,7 @@ if ProcessInfo.processInfo.environment["SWIFTCI_DISABLE_SDK_DEPENDENT_TESTS"] ==
             name: "IntegrationTests",
             dependencies: [
                 "_IntegrationTestSupport",
+                "_InternalTestSupport",
                 .product(name: "TSCTestSupport", package: "swift-tools-support-core"),
                 .product(name: "SwiftToolsSupport-auto", package: "swift-tools-support-core"),
         ]

Sources/_IntegrationTestSupport/Process.swift

@@ -10,6 +10,8 @@
 
 import Foundation
 import TSCTestSupport
+import _InternalTestSupport
+
 public class StringChecker {
     private let string: String
     private let lines: [Substring]

Sources/_IntegrationTestSupport/SkippedTestSupport.swift

@@ -10,6 +10,7 @@
 
 import Foundation
 import _IntegrationTestSupport
+import _InternalTestSupport
 import Testing
 import TSCBasic
 import TSCTestSupport

Sources/_IntegrationTestSupport/StringChecker.swift

@@ -10,6 +10,7 @@
 
 import Foundation
 import _IntegrationTestSupport
+import _InternalTestSupport
 import Testing
 import TSCBasic
 import TSCTestSupport
@@ -75,15 +76,6 @@ private struct SwiftPMTests {
     }
 
     @Test(
-        .requireThreadSafeWorkingDirectory,
-        arguments: [BuildSystemProvider.native]
-    )
-    func packageInitExecutable(_ buildSystemProvider: BuildSystemProvider) throws {
-        try _packageInitExecutable(buildSystemProvider)
-    }
-
-    @Test(
-        .skipHostOS(.windows),
         .requireThreadSafeWorkingDirectory,
         .bug(
             "https://github.com/swiftlang/swift-package-manager/issues/8416",
@@ -93,13 +85,9 @@ private struct SwiftPMTests {
             "https://github.com/swiftlang/swift-package-manager/issues/8514",
             "[Windows] Integration test SwiftPMTests.packageInitExecutable with --build-system swiftbuild is skipped"
         ),
-        arguments: [BuildSystemProvider.swiftbuild]
+        arguments: BuildSystemProvider.allCases
     )
-    func packageInitExecutablSkipWindows(_ buildSystemProvider: BuildSystemProvider) throws {
-        try _packageInitExecutable(buildSystemProvider)
-    }
-
-    private func _packageInitExecutable(_ buildSystemProvider: BuildSystemProvider) throws {
+    func packageInitExecutable(_ buildSystemProvider: BuildSystemProvider) throws {
         try withTemporaryDirectory { tmpDir in
             let packagePath = tmpDir.appending(component: "foo")
             try localFileSystem.createDirectory(packagePath)
@@ -119,7 +107,7 @@ private struct SwiftPMTests {
                 #expect(!runOutput.stderr.contains("error:"))
                 #expect(runOutput.stdout.contains("Hello, world!"))
             } when: {
-                buildSystemProvider == .swiftbuild && ProcessInfo.hostOperatingSystem == .linux
+                buildSystemProvider == .swiftbuild && [OperatingSystem.linux, .windows].contains(ProcessInfo.hostOperatingSystem)
             }
         }
     }

Tests/IntegrationTests/BasicTests.swift

@@ -11,6 +11,7 @@
 import TSCBasic
 import TSCTestSupport
 import _IntegrationTestSupport
+import _InternalTestSupport
 import Testing
 
 @Suite