Restore test cases and fix compile error

Author: cmcgee1024

Tests/CommandsTests/CommandsTestCase.swift

@@ -38,6 +38,7 @@ class CommandsTestCase: XCTestCase {
 class CommandsBuildProviderTestCase: BuildSystemProviderTestCase {
     /// Original working directory before the test ran (if known).
     private var originalWorkingDirectory: AbsolutePath? = .none
+    let duplicateSymbolRegex = StringPattern.regex(".*One of the duplicates must be removed or renamed.")
 
     override func setUp() {
         originalWorkingDirectory = localFileSystem.currentWorkingDirectory

Tests/CommandsTests/RunCommandTests.swift

@@ -48,6 +48,12 @@ class RunCommandTestCase: CommandsBuildProviderTestCase {
         XCTAssert(stdout.contains("SEE ALSO: swift build, swift package, swift test"), "got stdout:\n" + stdout)
     }
 
+    func testCommandDoesNotEmitDuplicateSymbols() async throws {
+        let (stdout, stderr) = try await execute(["--help"])
+        XCTAssertNoMatch(stdout, duplicateSymbolRegex)
+        XCTAssertNoMatch(stderr, duplicateSymbolRegex)
+    }
+
     func testVersion() async throws {
         let stdout = try await execute(["--version"]).stdout
         XCTAssertMatch(stdout, .regex(#"Swift Package Manager -( \w+ )?\d+.\d+.\d+(-\w+)?"#))
@@ -262,6 +268,6 @@ class RunCommandSwiftBuildTests: RunCommandTestCase {
     }
 
     override func testUnreachableExecutable() async throws {
-        throw XCTSkip("SWBINTTODO: Test fails because of build layout differences.)
+        throw XCTSkip("SWBINTTODO: Test fails because of build layout differences.")
     }
 }

Tests/CommandsTests/SwiftSDKCommandTests.swift

@@ -32,6 +32,14 @@ final class SwiftSDKCommandTests: CommandsTestCase {
         }
     }
 
+    func testCommandDoesNotEmitDuplicateSymbols() async throws {
+        for command in [SwiftPM.sdk, SwiftPM.experimentalSDK] {
+            let (stdout, stderr) = try await command.execute(["--help"])
+            XCTAssertNoMatch(stdout, duplicateSymbolRegex)
+            XCTAssertNoMatch(stderr, duplicateSymbolRegex)
+        }
+    }
+
     func testVersionS() async throws {
         for command in [SwiftPM.sdk, SwiftPM.experimentalSDK] {
             let stdout = try await command.execute(["--version"]).stdout