[Workspace] Diagnose duplicate root packages

<rdar://problem/47031631>

Author: aciidgh

Sources/TestSupport/TestWorkspace.swift

@@ -38,7 +38,6 @@ public final class TestWorkspace {
  toolsVersion: ToolsVersion = ToolsVersion.currentToolsVersion,
  skipUpdate: Bool = false
  ) throws {
- precondition(Set(roots.map({$0.name})).count == roots.count, "Root packages should be unique")
  self.sandbox = sandbox
  self.fs = fs
  self.config = SwiftPMConfig(path: sandbox.appending(component: "swiftpm"), fs: fs)
@@ -155,7 +154,7 @@ public final class TestWorkspace {
  }
 
  public func rootPaths(for packages: [String]) -> [AbsolutePath] {
- return packages.map({ rootsDir.appending(component: $0) })
+ return packages.map({ rootsDir.appending(RelativePath($0)) })
  }
 
  public struct PackageDependency {

Sources/Workspace/Diagnostics.swift

@@ -443,4 +443,16 @@ public enum WorkspaceDiagnostics {
  }
  )
  }
+
+ public struct DuplicateRoots: DiagnosticData {
+ public static let id = DiagnosticID(
+ type: DuplicateRoots.self,
+ name: "org.swift.diags.workspace.\(DuplicateRoots.self)",
+ description: {
+ $0 <<< "found multiple top-level packages named" <<< { "'" + $0.name + "'" }
+ }
+ )
+
+ let name: String
+ }
 }

Sources/Workspace/Workspace.swift

@@ -665,9 +665,18 @@ extension Workspace {
  packages: [AbsolutePath],
  diagnostics: DiagnosticsEngine
  ) -> [Manifest] {
- return packages.compactMap({ package -> Manifest? in
-loadManifest(packagePath: package, url: package.asString, diagnostics: diagnostics)
+ let rootManifests = packages.compactMap({ package -> Manifest? in
+ loadManifest(packagePath: package, url: package.asString, diagnostics: diagnostics)
  })
+
+ // Check for duplicate root packages.
+ let duplicateRoots = rootManifests.spm_findDuplicateElements(by: \.name)
+ if !duplicateRoots.isEmpty {
+ diagnostics.emit(data: WorkspaceDiagnostics.DuplicateRoots(name: duplicateRoots[0][0].name))
+ return []
+ }
+
+ return rootManifests
  }
 }
 

Tests/WorkspaceTests/WorkspaceTests.swift

@@ -225,6 +225,42 @@ final class WorkspaceTests: XCTestCase {
  }
  }
 
+func testDuplicateRootPackages() throws {
+ let sandbox = AbsolutePath("/tmp/ws/")
+ let fs = InMemoryFileSystem()
+
+ let workspace = try TestWorkspace(
+ sandbox: sandbox,
+ fs: fs,
+ roots: [
+ TestPackage(
+ name: "Foo",
+ targets: [
+ TestTarget(name: "Foo", dependencies: []),
+ ],
+ products: [],
+ dependencies: []
+ ),
+ TestPackage(
+ name: "Foo",
+ path: "Nested/Foo",
+ targets: [
+ TestTarget(name: "Foo", dependencies: []),
+ ],
+ products: [],
+ dependencies: []
+ ),
+ ],
+ packages: []
+ )
+
+ workspace.checkPackageGraph(roots: ["Foo", "Nested/Foo"]) { (graph, diagnostics) in
+ DiagnosticsEngineTester(diagnostics) { result in
+ result.check(diagnostic: .equal("found multiple top-level packages named 'Foo'"), behavior: .error)
+ }
+ }
+ }
+
  /// Test that the remote repository is not resolved when a root package with same name is already present.
  func testRootAsDependency1() throws {
  let sandbox = AbsolutePath("/tmp/ws/")

Tests/WorkspaceTests/XCTestManifests.swift

@@ -52,6 +52,7 @@ extension WorkspaceTests {
  ("testDependencyManifestsOrder", testDependencyManifestsOrder),
  ("testDependencyResolutionWithEdit", testDependencyResolutionWithEdit),
  ("testDependencySwitchWithSameIdentity", testDependencySwitchWithSameIdentity),
+ ("testDuplicateRootPackages", testDuplicateRootPackages),
  ("testEditDependency", testEditDependency),
  ("testForceResolveToResolvedVersions", testForceResolveToResolvedVersions),
  ("testGraphRootDependencies", testGraphRootDependencies),