Add negative dart:_wasm test, fix SdkLibrary.isInternal

While doing a previous CL, noticed that we don't actually report
the corresponding error.

Change-Id: I77ae11de6f6e84b3625b13db803e846966c806d6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/333641
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
Reviewed-by: Samuel Rawlins <srawlins@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>

pkg/analyzer/lib/src/generated/sdk.dart

@@ -349,7 +349,7 @@ class SdkLibraryImpl implements SdkLibrary {
   bool get isImplementation => _implementation;
 
   @override
-  bool get isInternal => category == "Internal";
+  bool get isInternal => shortName.startsWith('dart:_');
 
   @override
   bool get isShared => category == "Shared";

pkg/analyzer/test/src/dart/analysis/search_test.dart

@@ -714,7 +714,7 @@ class A {}
 
     // Configure `package:my`.
     writePackageConfig(
-      getFile('${myRoot.path}/.dart_tool/package_config.json').path,
+      myRoot.path,
       PackageConfigFileBuilder()..add(name: 'my', rootPath: myRoot.path),
     );
 

pkg/analyzer/test/src/dart/resolution/context_collection_resolution.dart

@@ -353,12 +353,8 @@ class PubPackageResolutionTest extends ContextResolutionTest {
   }) async {
     final rootFolder = getFolder('$workspaceRootPath/foo');
 
-    final packageConfigFile = getFile(
-      '${rootFolder.path}/.dart_tool/package_config.json',
-    );
-
     writePackageConfig(
-      packageConfigFile.path,
+      rootFolder.path,
       PackageConfigFileBuilder()..add(name: 'foo', rootPath: rootFolder.path),
     );
 
@@ -399,13 +395,14 @@ class PubPackageResolutionTest extends ContextResolutionTest {
     );
   }
 
-  void writePackageConfig(String path, PackageConfigFileBuilder config) {
-    newFile(
-      path,
-      config.toContent(
-        toUriStr: toUriStr,
-      ),
+  void writePackageConfig(
+    String directoryPath,
+    PackageConfigFileBuilder config,
+  ) {
+    final content = config.toContent(
+      toUriStr: toUriStr,
     );
+    newPackageConfigJsonFile(directoryPath, content);
   }
 
   Future<File> writeSdkSummary() async {
@@ -488,8 +485,7 @@ class PubPackageResolutionTest extends ContextResolutionTest {
       );
     }
 
-    var path = '$testPackageRootPath/.dart_tool/package_config.json';
-    writePackageConfig(path, config);
+    writePackageConfig(testPackageRootPath, config);
   }
 
   void writeTestPackageConfigWithMeta() {

pkg/analyzer/test/src/diagnostics/import_internal_library_test.dart

@@ -30,8 +30,8 @@ import 'dart:_internal';
   }
 
   test_wasm_fromJs() async {
-    var filePath = _pathInPackage('js');
-    final file = newFile(filePath, '''
+    final packageRootPath = _newPackage('js');
+    final file = newFile('$packageRootPath/lib/js.dart', '''
 import 'dart:_wasm';
 ''');
     await resolveFile2(file);
@@ -40,9 +40,18 @@ import 'dart:_wasm';
     ]);
   }
 
+  test_wasm_fromTest() async {
+    await assertErrorsInCode('''
+import 'dart:_wasm';
+''', [
+      error(CompileTimeErrorCode.IMPORT_INTERNAL_LIBRARY, 7, 12),
+      error(WarningCode.UNUSED_IMPORT, 7, 12),
+    ]);
+  }
+
   test_wasm_fromUi() async {
-    var filePath = _pathInPackage('ui');
-    final file = newFile(filePath, '''
+    final packageRootPath = _newPackage('ui');
+    final file = newFile('$packageRootPath/lib/ui.dart', '''
 import 'dart:_wasm';
 ''');
     await resolveFile2(file);
@@ -51,16 +60,15 @@ import 'dart:_wasm';
     ]);
   }
 
-  String _pathInPackage(String packageName) {
-    var packageRoot = '$workspaceRootPath/$packageName';
+  String _newPackage(String packageName) {
+    var packageRootPath = '$workspaceRootPath/$packageName';
     var builder = PackageConfigFileBuilder();
     builder.add(
       name: packageName,
-      rootPath: packageRoot,
+      rootPath: packageRootPath,
       languageVersion: testPackageLanguageVersion,
     );
-    var path = '$packageRoot/.dart_tool/package_config.json';
-    writePackageConfig(path, builder);
-    return '$packageRoot/lib/$packageName.dart';
+    writePackageConfig(packageRootPath, builder);
+    return packageRootPath;
   }
 }