tests: silence debug output, simplify and tighten checks

Use the `assertDriverDiagnostics` helper to ensure that all the emitted
diagnostics are verified. Remove the debug printing and output to the
logs. This is no longer necessary as we will verify that any additional
diagnostics emitted are checked and the helper will render the missed or
non-matching diagnostics allowing easy triaging of the failures in CI.

Author: compnerd

Tests/SwiftDriverTests/ExplicitModuleBuildTests.swift

@@ -2216,55 +2216,51 @@ final class ExplicitModuleBuildTests: XCTestCase {
 
       // Detailed explain (all possible paths)
       do {
-        var driver = try Driver(args: ["swiftc",
-                                       "-I", cHeadersPath.nativePathString(escaped: true),
-                                       "-I", swiftModuleInterfacesPath.nativePathString(escaped: true),
-                                       "-explicit-module-build",
-                                       "-module-cache-path", moduleCachePath.nativePathString(escaped: true),
-                                       "-working-directory", path.nativePathString(escaped: true),
-                                       "-explain-module-dependency-detailed", "A",
-                                       main.nativePathString(escaped: true)] + sdkArgumentsForTesting)
-        let jobs = try driver.planBuild()
-        try driver.run(jobs: jobs)
-        XCTAssertTrue(!driver.diagnosticEngine.diagnostics.isEmpty)
-        XCTAssertTrue(driver.diagnosticEngine.diagnostics.contains { $0.behavior == .remark &&
-          $0.message.text == "Module 'testTraceDependency' depends on 'A'"})
-
-        for diag in driver.diagnosticEngine.diagnostics {
-          print(diag.behavior)
-          print(diag.message)
+        try assertDriverDiagnostics(args: [
+            "swiftc",
+            "-I", cHeadersPath.nativePathString(escaped: true),
+            "-I", swiftModuleInterfacesPath.nativePathString(escaped: true),
+            "-explicit-module-build",
+            "-module-cache-path", moduleCachePath.nativePathString(escaped: true),
+            "-working-directory", path.nativePathString(escaped: true),
+            "-explain-module-dependency-detailed", "A",
+            main.nativePathString(escaped: true)
+        ] + sdkArgumentsForTesting) { driver, diagnostics in
+          diagnostics.forbidUnexpected(.error, .warning, .note, .remark)
+
+          let jobs = try driver.planBuild()
+          try driver.run(jobs: jobs)
+
+          diagnostics.expect(.remark("Module 'testTraceDependency' depends on 'A'"))
+          diagnostics.expect(.note("[testTraceDependency] -> [A] -> [A](ObjC)"))
+          diagnostics.expect(.note("[testTraceDependency] -> [C](ObjC) -> [B](ObjC) -> [A](ObjC)"))
         }
-        XCTAssertEqual(driver.diagnosticEngine.diagnostics.filter { $0.behavior == .note}.count, 2)
-        XCTAssertTrue(driver.diagnosticEngine.diagnostics.contains { $0.behavior == .note &&
-          $0.message.text == "[testTraceDependency] -> [A] -> [A](ObjC)"})
-        XCTAssertTrue(driver.diagnosticEngine.diagnostics.contains { $0.behavior == .note &&
-          $0.message.text == "[testTraceDependency] -> [C](ObjC) -> [B](ObjC) -> [A](ObjC)"})
       }
 
       // Simple explain (first available path)
       do {
-        var driver = try Driver(args: ["swiftc",
-                                       "-I", cHeadersPath.nativePathString(escaped: true),
-                                       "-I", swiftModuleInterfacesPath.nativePathString(escaped: true),
-                                       "-explicit-module-build",
-                                       "-module-cache-path", moduleCachePath.nativePathString(escaped: true),
-                                       "-working-directory", path.nativePathString(escaped: true),
-                                       "-explain-module-dependency", "A",
-                                       main.nativePathString(escaped: true)] + sdkArgumentsForTesting)
-        let jobs = try driver.planBuild()
-        try driver.run(jobs: jobs)
-        XCTAssertTrue(!driver.diagnosticEngine.diagnostics.isEmpty)
-        XCTAssertTrue(driver.diagnosticEngine.diagnostics.contains { $0.behavior == .remark &&
-          $0.message.text == "Module 'testTraceDependency' depends on 'A'"})
-
-        for diag in driver.diagnosticEngine.diagnostics {
-          print(diag.behavior)
-          print(diag.message)
+        try assertDriverDiagnostics(args:[
+            "swiftc",
+            "-I", cHeadersPath.nativePathString(escaped: true),
+            "-I", swiftModuleInterfacesPath.nativePathString(escaped: true),
+            "-explicit-module-build",
+            "-module-cache-path", moduleCachePath.nativePathString(escaped: true),
+            "-working-directory", path.nativePathString(escaped: true),
+            "-explain-module-dependency", "A",
+            main.nativePathString(escaped: true)
+        ] + sdkArgumentsForTesting) { driver, diagnostics in
+          diagnostics.forbidUnexpected(.error, .warning, .note, .remark)
+
+          let jobs = try driver.planBuild()
+          try driver.run(jobs: jobs)
+
+          diagnostics.expect(.remark("Module 'testTraceDependency' depends on 'A'"))
+#if os(macOS)
+          diagnostics.expect(.note("[testTraceDependency] -> [A] -> [A](ObjC)"))
+#else
+          diagnostics.expect(.note("[testTraceDependency] -> [C](ObjC) -> [B](ObjC) -> [A](ObjC)"))
+#endif
         }
-        XCTAssertEqual(driver.diagnosticEngine.diagnostics.filter { $0.behavior == .note}.count, 1)
-        XCTAssertTrue(driver.diagnosticEngine.diagnostics.contains { $0.behavior == .note &&
-          ($0.message.text == "[testTraceDependency] -> [A] -> [A](ObjC)" ||
-           $0.message.text == "[testTraceDependency] -> [C](ObjC) -> [B](ObjC) -> [A](ObjC)")})
       }
     }
   }