[NFC] Rename SPMTestSupport to _InternalTestSupport (#7676)

There's no such product or entity as "SPM", this contraction is just as
invalid as "MOS" would be for macOS, or "SNIO" for SwiftNIO. All
marketing and documentation materials consistently refer to it as
"SwiftPM", and we should stay consistent in our codebase too. This also
simplifies code search, as anything named as "SPM" almost never shows up
in results when searching globally for "SwiftPM".

We're not using `SwiftPMTestSupport` name here, as it might mislead
contributors into thinking this module is somehow related to the `swift
test` command. This module is purely internal, used only in modules with
unit tests for SwiftPM itself, and is not supposed to be used by any
packages depending on SwiftPM. Thus all `@_spi` declarations in it were
also changed to `package`.

Author: MaxDesiatov

Package.swift

@@ -592,8 +592,8 @@ let package = Package(
         // MARK: Additional Test Dependencies
 
         .target(
-            /** SwiftPM test support library */
-            name: "SPMTestSupport",
+            /** SwiftPM internal test suite support library */
+            name: "_InternalTestSupport",
             dependencies: [
                 "Basics",
                 "Build",
@@ -621,13 +621,13 @@ let package = Package(
             name: "SourceKitLSPAPITests",
             dependencies: [
                 "SourceKitLSPAPI",
-                "SPMTestSupport",
+                "_InternalTestSupport",
             ]
         ),
 
         .testTarget(
             name: "BasicsTests",
-            dependencies: ["Basics", "SPMTestSupport", "tsan_utils"],
+            dependencies: ["Basics", "_InternalTestSupport", "tsan_utils"],
             exclude: [
                 "Archiver/Inputs/archive.tar.gz",
                 "Archiver/Inputs/archive.zip",
@@ -637,48 +637,48 @@ let package = Package(
         ),
         .testTarget(
             name: "BuildTests",
-            dependencies: ["Build", "PackageModel", "SPMTestSupport"]
+            dependencies: ["Build", "PackageModel", "_InternalTestSupport"]
         ),
         .testTarget(
             name: "LLBuildManifestTests",
-            dependencies: ["Basics", "LLBuildManifest", "SPMTestSupport"]
+            dependencies: ["Basics", "LLBuildManifest", "_InternalTestSupport"]
         ),
         .testTarget(
             name: "WorkspaceTests",
-            dependencies: ["Workspace", "SPMTestSupport"]
+            dependencies: ["Workspace", "_InternalTestSupport"]
         ),
         .testTarget(
             name: "PackageDescriptionTests",
             dependencies: ["PackageDescription"]
         ),
         .testTarget(
             name: "SPMBuildCoreTests",
-            dependencies: ["SPMBuildCore", "SPMTestSupport"]
+            dependencies: ["SPMBuildCore", "_InternalTestSupport"]
         ),
         .testTarget(
             name: "PackageLoadingTests",
-            dependencies: ["PackageLoading", "SPMTestSupport"],
+            dependencies: ["PackageLoading", "_InternalTestSupport"],
             exclude: ["Inputs", "pkgconfigInputs"]
         ),
         .testTarget(
             name: "PackageModelTests",
-            dependencies: ["PackageModel", "SPMTestSupport"]
+            dependencies: ["PackageModel", "_InternalTestSupport"]
         ),
         .testTarget(
             name: "PackageModelSyntaxTests",
             dependencies: [
                 "PackageModelSyntax",
-                "SPMTestSupport",
+                "_InternalTestSupport",
                 .product(name: "SwiftIDEUtils", package: "swift-syntax"),
             ]
         ),
         .testTarget(
             name: "PackageGraphTests",
-            dependencies: ["PackageGraph", "SPMTestSupport"]
+            dependencies: ["PackageGraph", "_InternalTestSupport"]
         ),
         .testTarget(
             name: "PackageGraphPerformanceTests",
-            dependencies: ["PackageGraph", "SPMTestSupport"],
+            dependencies: ["PackageGraph", "_InternalTestSupport"],
             exclude: [
                 "Inputs/PerfectHTTPServer.json",
                 "Inputs/ZewoHTTPServer.json",
@@ -688,44 +688,44 @@ let package = Package(
         ),
         .testTarget(
             name: "PackageCollectionsModelTests",
-            dependencies: ["PackageCollectionsModel", "SPMTestSupport"]
+            dependencies: ["PackageCollectionsModel", "_InternalTestSupport"]
         ),
         .testTarget(
             name: "PackageCollectionsSigningTests",
-            dependencies: ["PackageCollectionsSigning", "SPMTestSupport"]
+            dependencies: ["PackageCollectionsSigning", "_InternalTestSupport"]
         ),
         .testTarget(
             name: "PackageCollectionsTests",
-            dependencies: ["PackageCollections", "SPMTestSupport", "tsan_utils"]
+            dependencies: ["PackageCollections", "_InternalTestSupport", "tsan_utils"]
         ),
         .testTarget(
             name: "PackageFingerprintTests",
-            dependencies: ["PackageFingerprint", "SPMTestSupport"]
+            dependencies: ["PackageFingerprint", "_InternalTestSupport"]
         ),
         .testTarget(
             name: "PackagePluginAPITests",
-            dependencies: ["PackagePlugin", "SPMTestSupport"]
+            dependencies: ["PackagePlugin", "_InternalTestSupport"]
         ),
         .testTarget(
             name: "PackageRegistryTests",
-            dependencies: ["SPMTestSupport", "PackageRegistry"]
+            dependencies: ["_InternalTestSupport", "PackageRegistry"]
         ),
         .testTarget(
             name: "PackageSigningTests",
-            dependencies: ["SPMTestSupport", "PackageSigning"]
+            dependencies: ["_InternalTestSupport", "PackageSigning"]
         ),
         .testTarget(
             name: "QueryEngineTests",
-            dependencies: ["QueryEngine", "SPMTestSupport"]
+            dependencies: ["QueryEngine", "_InternalTestSupport"]
         ),
         .testTarget(
             name: "SourceControlTests",
-            dependencies: ["SourceControl", "SPMTestSupport"],
+            dependencies: ["SourceControl", "_InternalTestSupport"],
             exclude: ["Inputs/TestRepo.tgz"]
         ),
         .testTarget(
             name: "XCBuildSupportTests",
-            dependencies: ["XCBuildSupport", "SPMTestSupport"],
+            dependencies: ["XCBuildSupport", "_InternalTestSupport"],
             exclude: ["Inputs/Foo.pc"]
         ),
         // Examples (These are built to ensure they stay up to date with the API.)
@@ -746,7 +746,7 @@ package.targets.append(contentsOf: [
         name: "FunctionalPerformanceTests",
         dependencies: [
             "swift-package-manager",
-            "SPMTestSupport",
+            "_InternalTestSupport",
         ]
     ),
 ])
@@ -760,7 +760,7 @@ if ProcessInfo.processInfo.environment["SWIFTCI_DISABLE_SDK_DEPENDENT_TESTS"] ==
             dependencies: [
                 "swift-package-manager",
                 "PackageModel",
-                "SPMTestSupport",
+                "_InternalTestSupport",
             ]
         ),
 
@@ -782,7 +782,7 @@ if ProcessInfo.processInfo.environment["SWIFTCI_DISABLE_SDK_DEPENDENT_TESTS"] ==
                 "PackageModelSyntax",
                 "PackageRegistryCommand",
                 "SourceControl",
-                "SPMTestSupport",
+                "_InternalTestSupport",
                 "Workspace",
                 "dummy-swiftc",
             ]

Sources/SPMTestSupport/GitRepositoryExtensions.swift renamed to Sources/_InternalTestSupport/GitRepositoryExtensions.swift

@@ -26,15 +26,13 @@ import struct PackageModel.TargetDescription
 import protocol TSCBasic.FileSystem
 import class TSCBasic.InMemoryFileSystem
 
-@_spi(SwiftPMInternal)
-public typealias MockPackageGraph = (
+package typealias MockPackageGraph = (
     graph: ModulesGraph,
     fileSystem: any FileSystem,
     observabilityScope: ObservabilityScope
 )
 
-@_spi(SwiftPMInternal)
-public func macrosPackageGraph() throws -> MockPackageGraph {
+package func macrosPackageGraph() throws -> MockPackageGraph {
     let fs = InMemoryFileSystem(emptyFiles:
         "/swift-firmware/Sources/Core/source.swift",
         "/swift-firmware/Sources/HAL/source.swift",
@@ -132,8 +130,7 @@ public func macrosPackageGraph() throws -> MockPackageGraph {
     return (graph, fs, observability.topScope)
 }
 
-@_spi(SwiftPMInternal)
-public func macrosTestsPackageGraph() throws -> MockPackageGraph {
+package func macrosTestsPackageGraph() throws -> MockPackageGraph {
     let fs = InMemoryFileSystem(emptyFiles:
         "/swift-mmio/Plugins/MMIOPlugin/source.swift",
         "/swift-mmio/Sources/MMIO/source.swift",
@@ -282,8 +279,7 @@ public func macrosTestsPackageGraph() throws -> MockPackageGraph {
     return (graph, fs, observability.topScope)
 }
 
-@_spi(SwiftPMInternal)
-public func trivialPackageGraph() throws -> MockPackageGraph {
+package func trivialPackageGraph() throws -> MockPackageGraph {
     let fs = InMemoryFileSystem(
         emptyFiles:
         "/Pkg/Sources/app/main.swift",
@@ -313,8 +309,7 @@ public func trivialPackageGraph() throws -> MockPackageGraph {
     return (graph, fs, observability.topScope)
 }
 
-@_spi(SwiftPMInternal)
-public func embeddedCxxInteropPackageGraph() throws -> MockPackageGraph {
+package func embeddedCxxInteropPackageGraph() throws -> MockPackageGraph {
     let fs = InMemoryFileSystem(
         emptyFiles:
         "/Pkg/Sources/app/main.swift",
@@ -356,8 +351,7 @@ public func embeddedCxxInteropPackageGraph() throws -> MockPackageGraph {
     return (graph, fs, observability.topScope)
 }
 
-@_spi(SwiftPMInternal)
-public func toolsExplicitLibrariesGraph(linkage: ProductType.LibraryType) throws -> MockPackageGraph {
+package func toolsExplicitLibrariesGraph(linkage: ProductType.LibraryType) throws -> MockPackageGraph {
     let fs = InMemoryFileSystem(emptyFiles:
         "/swift-mmio/Sources/MMIOMacros/source.swift",
         "/swift-mmio/Sources/MMIOMacrosTests/source.swift",

Sources/SPMTestSupport/InMemoryGitRepository.swift renamed to Sources/_InternalTestSupport/InMemoryGitRepository.swift

@@ -12,7 +12,7 @@
 
 import Basics
 import TSCclibc // for SPM_posix_spawn_file_actions_addchdir_np_supported
-import SPMTestSupport
+import _InternalTestSupport
 import XCTest
 
 import class TSCBasic.InMemoryFileSystem

Sources/SPMTestSupport/ManifestExtensions.swift renamed to Sources/_InternalTestSupport/ManifestExtensions.swift

@@ -12,7 +12,7 @@
 
 import Basics
 import TSCclibc // for SPM_posix_spawn_file_actions_addchdir_np_supported
-import SPMTestSupport
+import _InternalTestSupport
 import XCTest
 
 import class TSCBasic.InMemoryFileSystem

Sources/SPMTestSupport/MockArchiver.swift renamed to Sources/_InternalTestSupport/MockArchiver.swift

@@ -11,7 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 import Basics
-import SPMTestSupport
+import _InternalTestSupport
 import XCTest
 import TSCclibc // for SPM_posix_spawn_file_actions_addchdir_np_supported
 

Sources/SPMTestSupport/MockBuildTestHelper.swift renamed to Sources/_InternalTestSupport/MockBuildTestHelper.swift

@@ -11,7 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 @testable import Basics
-import SPMTestSupport
+import _InternalTestSupport
 import XCTest
 
 final class AuthorizationProviderTests: XCTestCase {

Sources/SPMTestSupport/MockDependency.swift renamed to Sources/_InternalTestSupport/MockDependency.swift

@@ -11,7 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 @testable import Basics
-import SPMTestSupport
+import _InternalTestSupport
 import XCTest
 
 import class Basics.AsyncProcess

Sources/SPMTestSupport/MockDependencyGraph.swift renamed to Sources/_InternalTestSupport/MockDependencyGraph.swift

@@ -11,7 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 @testable import Basics
-import SPMTestSupport
+import _InternalTestSupport
 import XCTest
 
 final class HTTPClientTests: XCTestCase {

Sources/SPMTestSupport/MockHTTPClient.swift renamed to Sources/_InternalTestSupport/MockHTTPClient.swift

@@ -11,7 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 @testable import Basics
-import SPMTestSupport
+import _InternalTestSupport
 import XCTest
 
 final class LegacyHTTPClientTests: XCTestCase {

Sources/SPMTestSupport/MockHashAlgorithm.swift renamed to Sources/_InternalTestSupport/MockHashAlgorithm.swift

@@ -11,7 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 @testable import Basics
-import SPMTestSupport
+import _InternalTestSupport
 import XCTest
 
 // TODO: remove when transition to new diagnostics system is complete

Sources/SPMTestSupport/MockManifestLoader.swift renamed to Sources/_InternalTestSupport/MockManifestLoader.swift

@@ -11,7 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 @testable import Basics
-import SPMTestSupport
+import _InternalTestSupport
 import tsan_utils
 import XCTest
 

Sources/SPMTestSupport/MockPackage.swift renamed to Sources/_InternalTestSupport/MockPackage.swift

@@ -11,7 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 @testable import Basics
-import SPMTestSupport
+import _InternalTestSupport
 import XCTest
 
 #if canImport(Darwin)

Sources/SPMTestSupport/MockPackageContainer.swift renamed to Sources/_InternalTestSupport/MockPackageContainer.swift

@@ -17,7 +17,7 @@ import Foundation
 // need to decide how to best deal with that
 import FoundationNetworking
 #endif
-import SPMTestSupport
+import _InternalTestSupport
 import XCTest
 
 import struct TSCBasic.ByteString

Sources/SPMTestSupport/MockPackageFingerprintStorage.swift renamed to Sources/_InternalTestSupport/MockPackageFingerprintStorage.swift

@@ -19,7 +19,7 @@ import LLBuildManifest
 import PackageGraph
 import SPMBuildCore
 @_spi(SwiftPMInternal)
-import SPMTestSupport
+import _InternalTestSupport
 import XCTest
 
 import class TSCBasic.BufferedOutputByteStream

Sources/SPMTestSupport/MockPackageGraphs.swift renamed to Sources/_InternalTestSupport/MockPackageGraphs.swift

@@ -26,7 +26,7 @@ import PackageLoading
 @testable import PackageModel
 
 import SPMBuildCore
-import SPMTestSupport
+import _InternalTestSupport
 import SwiftDriver
 import Workspace
 import XCTest

Sources/SPMTestSupport/MockPackageSigningEntityStorage.swift renamed to Sources/_InternalTestSupport/MockPackageSigningEntityStorage.swift

@@ -11,7 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 import PackageModel
-import SPMTestSupport
+import _InternalTestSupport
 import XCTest
 
 import var TSCBasic.localFileSystem

Sources/SPMTestSupport/MockProduct.swift renamed to Sources/_InternalTestSupport/MockProduct.swift

@@ -15,7 +15,7 @@ import Basics
 import PackageGraph
 import PackageModel
 import SPMBuildCore
-import SPMTestSupport
+import _InternalTestSupport
 import XCTest
 
 final class ClangTargetBuildDescriptionTests: XCTestCase {

Sources/SPMTestSupport/MockRegistry.swift renamed to Sources/_InternalTestSupport/MockRegistry.swift

@@ -22,24 +22,19 @@ import class PackageModel.Manifest
 import struct PackageModel.TargetDescription
 import enum PackageModel.ProductType
 import struct SPMBuildCore.BuildParameters
-import func SPMTestSupport.loadPackageGraph
-
-@_spi(SwiftPMInternal)
-import func SPMTestSupport.embeddedCxxInteropPackageGraph
-
-@_spi(SwiftPMInternal)
-import func SPMTestSupport.macrosPackageGraph
-import func SPMTestSupport.macrosTestsPackageGraph
-import func SPMTestSupport.mockBuildParameters
-import func SPMTestSupport.mockBuildPlan
-import func SPMTestSupport.toolsExplicitLibrariesGraph
-
-@_spi(SwiftPMInternal)
-import func SPMTestSupport.trivialPackageGraph
-
-import struct SPMTestSupport.BuildPlanResult
-import func SPMTestSupport.XCTAssertMatch
-import func SPMTestSupport.XCTAssertNoDiagnostics
+import func _InternalTestSupport.loadPackageGraph
+
+import func _InternalTestSupport.embeddedCxxInteropPackageGraph
+import func _InternalTestSupport.macrosPackageGraph
+import func _InternalTestSupport.macrosTestsPackageGraph
+import func _InternalTestSupport.mockBuildParameters
+import func _InternalTestSupport.mockBuildPlan
+import func _InternalTestSupport.toolsExplicitLibrariesGraph
+import func _InternalTestSupport.trivialPackageGraph
+
+import struct _InternalTestSupport.BuildPlanResult
+import func _InternalTestSupport.XCTAssertMatch
+import func _InternalTestSupport.XCTAssertNoDiagnostics
 import class TSCBasic.InMemoryFileSystem
 
 import XCTest