[analysis_server] Update plugin tests to work through test runner

This removes a use of `Platform.script` so the tests work through the test runner. It also extracts some common code between this and the other integration tests to remove some duplication.

Change-Id: Ia9d441424789ea99decb071f7fdc6c71c8e54a72
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/419860
Commit-Queue: Brian Wilkerson <[email protected]>
Reviewed-by: Brian Wilkerson <[email protected]>
Reviewed-by: Samuel Rawlins <[email protected]>

Author: DanTup

pkg/analysis_server/test/integration/lsp_server/integration_tests.dart

@@ -5,7 +5,6 @@
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
-import 'dart:isolate';
 
 import 'package:analysis_server/lsp_protocol/protocol.dart';
 import 'package:analysis_server/src/lsp/channel/lsp_byte_stream_channel.dart';
@@ -17,6 +16,7 @@ import 'package:path/path.dart';
 
 import '../../lsp/request_helpers_mixin.dart';
 import '../../lsp/server_abstract.dart';
+import '../../support/sdk_paths.dart';
 
 abstract class AbstractLspAnalysisServerIntegrationTest
     with
@@ -200,29 +200,7 @@ class LspServerClient {
     }
 
     var dartBinary = join(dartSdkPath, 'bin', 'dart');
-
-    // Setting the `TEST_SERVER_SNAPSHOT` env var to 'false' will disable the
-    // snapshot and run from source.
-    var useSnapshot = Platform.environment['TEST_SERVER_SNAPSHOT'] != 'false';
-    String serverPath;
-
-    if (useSnapshot) {
-      // TODO(dantup): Consider changing this to "dart language_server" and
-      //  sharing this code with legacy-server integration tests.
-      serverPath = normalize(
-        join(dartSdkPath, 'bin', 'snapshots', 'analysis_server.dart.snapshot'),
-      );
-    } else {
-      // Locate the root of the analysis server package without using
-      // `Platform.script` as it fails when run through the `dart test`.
-      // https://github.com/dart-lang/test/issues/110
-      var serverLibUri = await Isolate.resolvePackageUri(
-        Uri.parse('package:analysis_server/'),
-      );
-      serverPath = normalize(
-        join(serverLibUri!.toFilePath(), '..', 'bin', 'server.dart'),
-      );
-    }
+    var serverPath = getAnalysisServerPath(dartSdkPath);
 
     var arguments = [...?vmArgs, serverPath, '--lsp', '--suppress-analytics'];
     var process = await Process.start(

pkg/analysis_server/test/integration/support/integration_tests.dart

@@ -6,7 +6,6 @@ import 'dart:async';
 import 'dart:collection';
 import 'dart:convert';
 import 'dart:io';
-import 'dart:isolate';
 
 import 'package:analysis_server/protocol/protocol_constants.dart';
 import 'package:analysis_server/protocol/protocol_generated.dart';
@@ -21,6 +20,7 @@ import 'package:test/test.dart';
 
 import '../../analysis_server_base.dart' show analysisOptionsContent;
 import '../../support/configuration_files.dart';
+import '../../support/sdk_paths.dart';
 import 'integration_test_methods.dart';
 import 'protocol_matchers.dart';
 
@@ -677,34 +677,7 @@ class Server {
     _time.start();
 
     var dartBinary = path.join(dartSdkPath, 'bin', 'dart');
-
-    // Setting the `TEST_SERVER_SNAPSHOT` env var to 'false' will disable the
-    // snapshot and run from source.
-    var useSnapshot = Platform.environment['TEST_SERVER_SNAPSHOT'] != 'false';
-    String serverPath;
-
-    if (useSnapshot) {
-      // TODO(dantup): Consider changing this to "dart language_server" and
-      //  sharing this code with LSP integration tests.
-      serverPath = path.normalize(
-        path.join(
-          dartSdkPath,
-          'bin',
-          'snapshots',
-          'analysis_server.dart.snapshot',
-        ),
-      );
-    } else {
-      // Locate the root of the analysis server package without using
-      // `Platform.script` as it fails when run through the `dart test`.
-      // https://github.com/dart-lang/test/issues/110
-      var serverLibUri = await Isolate.resolvePackageUri(
-        Uri.parse('package:analysis_server/'),
-      );
-      serverPath = path.normalize(
-        path.join(serverLibUri!.toFilePath(), '..', 'bin', 'server.dart'),
-      );
-    }
+    var serverPath = getAnalysisServerPath(dartSdkPath);
 
     var arguments = <String>['--disable-dart-dev', '--no-dds'];
     //

pkg/analysis_server/test/src/plugin/plugin_manager_test.dart

@@ -23,6 +23,8 @@ import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 import 'package:watcher/watcher.dart' as watcher;
 
+import '../../support/sdk_paths.dart';
+
 void main() {
   defineReflectiveSuite(() {
     defineReflectiveTests(BuiltInPluginInfoTest);
@@ -876,19 +878,6 @@ class MinimalPlugin extends ServerPlugin {
 }
 ''';
 
-  /// The path to the package config file in the root of the Dart SDK.
-  static String get _sdkPackageConfigPath {
-    var filePath = io.Platform.script.toFilePath();
-    // Walk up the directory structure from this script file to the
-    // 'analysis_server' root directory.
-    while (filePath.isNotEmpty &&
-        path.basename(filePath) != 'analysis_server') {
-      filePath = path.dirname(filePath);
-    }
-    filePath = path.dirname(path.dirname(filePath));
-    return path.join(filePath, '.dart_tool', 'package_config.json');
-  }
-
   late PhysicalResourceProvider resourceProvider;
 
   late TestNotificationManager notificationManager;
@@ -930,7 +919,7 @@ class MinimalPlugin extends ServerPlugin {
         path.join(pluginDartToolPath, 'package_config.json'),
       );
       packageConfigFile.writeAsStringSync(
-        io.File(_sdkPackageConfigPath).readAsStringSync(),
+        io.File(sdkPackageConfigPath).readAsStringSync(),
       );
       //
       // Create the 'bin' directory.

pkg/analysis_server/test/support/sdk_paths.dart

@@ -0,0 +1,53 @@
+// Copyright (c) 2025, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:io';
+import 'dart:isolate';
+
+import 'package:path/path.dart' as path;
+
+/// The path of the `pkg/analysis_server` folder, resolved using the active
+/// `package_config.json`.
+String get analysisServerPackagePath {
+  // Locate the root of the analysis server package without using
+  // `Platform.script` as it fails when run through the `dart test`.
+  // https://github.com/dart-lang/test/issues/110
+  var serverLibUri = Isolate.resolvePackageUriSync(
+    Uri.parse('package:analysis_server/'),
+  );
+  return path.normalize(path.join(serverLibUri!.toFilePath(), '..'));
+}
+
+/// The path of the `package_config.json` file in the root of the SDK,
+/// computed by resolving the path to `pkg:analysis_server`.
+String get sdkPackageConfigPath {
+  return path.normalize(
+    path.join(sdkRootPath, '.dart_tool', 'package_config.json'),
+  );
+}
+
+/// The path the SDK, computed as the parent of the `pkg/analysis_server`
+/// folder, resolved using the active `package_config.json`.
+String get sdkRootPath {
+  return path.normalize(path.join(analysisServerPackagePath, '..', '..'));
+}
+
+/// Gets the path of the analysis server entry point which may be a snapshot
+/// or the source script depending on the `TEST_SERVER_SNAPSHOT` environment
+/// variable.
+String getAnalysisServerPath(String dartSdkPath) {
+  var snapshotPath = path.join(
+    dartSdkPath,
+    'bin',
+    'snapshots',
+    'analysis_server.dart.snapshot',
+  );
+  var sourcePath = path.join(analysisServerPackagePath, 'bin', 'server.dart');
+
+  // Setting the `TEST_SERVER_SNAPSHOT` env var to 'false' will disable the
+  // snapshot and run from source.
+  var useSnapshot = Platform.environment['TEST_SERVER_SNAPSHOT'] != 'false';
+  var serverPath = useSnapshot ? snapshotPath : sourcePath;
+  return path.normalize(serverPath);
+}