Cleanup the loader code to remove some unused pieces.

Change-Id: I026b2b0dfb964c2dd67a9022260e4aba9c019e9c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/125444
Commit-Queue: Siva Annamalai <asiva@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>

Author: a-siva

runtime/bin/vmservice/loader.dart

@@ -957,8 +957,6 @@ const _Dart_kCanonicalizeUrl = 0; // Canonicalize the URL.
 
 // Extra requests. Keep these in sync between loader.dart and builtin.dart.
 const _Dart_kInitLoader = 4; // Initialize the loader.
-const _Dart_kResourceLoad = 5; // Resource class support.
-const _Dart_kGetPackageRootUri = 6; // Uri of the packages/ directory.
 const _Dart_kGetPackageConfigUri = 7; // Uri of the .packages file.
 const _Dart_kResolvePackageUri = 8; // Resolve a package: uri.
 
@@ -1009,19 +1007,6 @@ _processLoadRequest(request) {
         assert(isolateEmbedderData[isolateId] == loaderState);
       }
       break;
-    case _Dart_kResourceLoad:
-      {
-        Uri uri = Uri.parse(request[4]);
-        _handleResourceRequest(
-            loaderState, sp, traceLoading, tag, uri, uri, null);
-      }
-      break;
-    case _Dart_kGetPackageRootUri:
-      loaderState._triggerPackageResolution(() {
-        // The package root is deprecated and now always returns null.
-        sp.send(null);
-      });
-      break;
     case _Dart_kGetPackageConfigUri:
       loaderState._triggerPackageResolution(() {
         // Respond with the packages config (if any) after package resolution.

runtime/vm/unit_test.cc

@@ -157,13 +157,6 @@ void SetupCoreLibrariesForUnitTest() {
   RELEASE_ASSERT(!Dart_IsError(result));
 }
 
-static const char* kPackageScheme = "package:";
-
-static bool IsPackageSchemeURL(const char* url_name) {
-  static const intptr_t kPackageSchemeLen = strlen(kPackageScheme);
-  return (strncmp(url_name, kPackageScheme, kPackageSchemeLen) == 0);
-}
-
 struct TestLibEntry {
   const char* url;
   const char* source;
@@ -212,13 +205,6 @@ static const char* IsolateReloadTestLibUri() {
   return "test:isolate_reload_helper";
 }
 
-static bool IsIsolateReloadTestLib(const char* url_name) {
-  static const intptr_t kIsolateReloadTestLibUriLen =
-      strlen(IsolateReloadTestLibUri());
-  return (strncmp(url_name, IsolateReloadTestLibUri(),
-                  kIsolateReloadTestLibUriLen) == 0);
-}
-
 static void ReloadTest(Dart_NativeArguments native_args) {
   Dart_Handle result = TestCase::TriggerReload(/* kernel_buffer= */ NULL,
                                                /* kernel_buffer_size= */ 0);
@@ -241,15 +227,6 @@ static Dart_Handle LoadIsolateReloadTestLib() {
 }
 #endif  // !PRODUCT
 
-static Dart_Handle ResolvePackageUri(const char* uri_chars) {
-  const int kNumArgs = 1;
-  Dart_Handle dart_args[kNumArgs];
-  dart_args[0] = DartUtils::NewString(uri_chars);
-  return Dart_Invoke(DartUtils::LookupBuiltinLib(),
-                     DartUtils::NewString("_filePathFromUri"), kNumArgs,
-                     dart_args);
-}
-
 char* TestCase::CompileTestScriptWithDFE(const char* url,
                                          const char* source,
                                          const uint8_t** kernel_buffer,
@@ -273,54 +250,6 @@ char* TestCase::CompileTestScriptWithDFE(const char* url,
       multiroot_filepaths, multiroot_scheme);
 }
 
-#if 0
-
-char* TestCase::CompileTestScriptWithDFE(const char* url,
-                                         int sourcefiles_count,
-                                         Dart_SourceFile sourcefiles[],
-                                         void** kernel_pgm,
-                                         bool incrementally,
-                                         bool allow_compile_errors) {
-  Zone* zone = Thread::Current()->zone();
-  Dart_KernelCompilationResult compilation_result = Dart_CompileSourcesToKernel(
-      url, platform_strong_dill, platform_strong_dill_size,
-      sourcefiles_count, sourcefiles, incrementally, NULL);
-  return ValidateCompilationResult(zone, compilation_result, kernel_pgm);
-}
-
-char* TestCase::ValidateCompilationResult(
-    Zone* zone,
-    Dart_KernelCompilationResult compilation_result,
-    void** kernel_pgm,
-    bool allow_compile_errors) {
-  if (!allow_compile_errors &&
-      (compilation_result.status != Dart_KernelCompilationStatus_Ok)) {
-    char* result =
-        OS::SCreate(zone, "Compilation failed %s", compilation_result.error);
-    free(compilation_result.error);
-    return result;
-  }
-
-  const uint8_t* kernel_file = compilation_result.kernel;
-  intptr_t kernel_length = compilation_result.kernel_size;
-  if (kernel_file == NULL) {
-    return OS::SCreate(zone, "front end generated a NULL kernel file");
-  }
-  *kernel_pgm =
-      Dart_ReadKernelBinary(kernel_file, kernel_length, ReleaseFetchedBytes);
-  if (*kernel_pgm == NULL) {
-    return OS::SCreate(zone, "Failed to read generated kernel binary");
-  }
-  if (compilation_result.status != Dart_KernelCompilationStatus_Ok) {
-    char* result =
-        OS::SCreate(zone, "Compilation failed %s", compilation_result.error);
-    free(compilation_result.error);
-    return result;
-  }
-  return NULL;
-}
-#endif
-
 char* TestCase::CompileTestScriptWithDFE(const char* url,
                                          int sourcefiles_count,
                                          Dart_SourceFile sourcefiles[],
@@ -377,70 +306,6 @@ static Dart_Handle LibraryTagHandler(Dart_LibraryTag tag,
     }
     return Dart_DefaultCanonicalizeUrl(library_url, url);
   }
-  if (!Dart_IsLibrary(library)) {
-    return Dart_NewApiError("not a library");
-  }
-  if (!Dart_IsString(url)) {
-    return Dart_NewApiError("url is not a string");
-  }
-  const char* url_chars = NULL;
-  Dart_Handle result = Dart_StringToCString(url, &url_chars);
-  if (Dart_IsError(result)) {
-    return Dart_NewApiError("accessing url characters failed");
-  }
-  Dart_Handle library_url = Dart_LibraryUrl(library);
-  const char* library_url_string = NULL;
-  result = Dart_StringToCString(library_url, &library_url_string);
-  if (Dart_IsError(result)) {
-    return result;
-  }
-
-  bool is_dart_scheme_url = DartUtils::IsDartSchemeURL(url_chars);
-  bool is_io_library = DartUtils::IsDartIOLibURL(library_url_string);
-  bool is_standalone_library = DartUtils::IsDartCLILibURL(library_url_string);
-  if (is_dart_scheme_url) {
-    ASSERT(tag == Dart_kImportTag);
-    // Handle imports of other built-in libraries present in the SDK.
-    if (DartUtils::IsDartIOLibURL(url_chars)) {
-      return Builtin::LoadAndCheckLibrary(Builtin::kIOLibrary);
-    } else if (DartUtils::IsDartBuiltinLibURL(url_chars)) {
-      return Builtin::LoadAndCheckLibrary(Builtin::kBuiltinLibrary);
-    } else if (DartUtils::IsDartCLILibURL(url_chars)) {
-      return Builtin::LoadAndCheckLibrary(Builtin::kCLILibrary);
-    } else {
-      return DartUtils::NewError("Do not know how to load '%s'", url_chars);
-    }
-  }
-  const char* lib_source = TestCase::GetTestLib(url_chars);
-  if (lib_source != NULL) {
-    UNREACHABLE();
-  }
-#if !defined(PRODUCT)
-  if (IsIsolateReloadTestLib(url_chars)) {
-    UNREACHABLE();
-    return Dart_Null();
-  }
-#endif
-  if (is_io_library) {
-    UNREACHABLE();
-    return Dart_Null();
-  }
-  if (is_standalone_library) {
-    UNREACHABLE();
-    return Dart_Null();
-  }
-  Dart_Handle resolved_url = url;
-  const char* resolved_url_chars = url_chars;
-  if (IsPackageSchemeURL(url_chars)) {
-    resolved_url = ResolvePackageUri(url_chars);
-    EXPECT_VALID(resolved_url);
-    if (Dart_IsError(Dart_StringToCString(resolved_url, &resolved_url_chars))) {
-      return Dart_NewApiError("unable to convert resolved uri to string");
-    }
-  }
-  // Do sync loading since unit_test doesn't support async.
-  Dart_Handle source = DartUtils::ReadStringFromFile(resolved_url_chars);
-  EXPECT_VALID(source);
   UNREACHABLE();
   return Dart_Null();
 }

sdk/lib/_internal/vm/bin/builtin.dart

@@ -47,8 +47,6 @@ int _isolateId;
 // Requests made to the service isolate over the load port.
 
 // Extra requests. Keep these in sync between loader.dart and builtin.dart.
-const _Dart_kResourceLoad = 5; // Resource class support.
-const _Dart_kGetPackageRootUri = 6; // Uri of the packages/ directory.
 const _Dart_kGetPackageConfigUri = 7; // Uri of the .packages file.
 const _Dart_kResolvePackageUri = 8; // Resolve a package: uri.
 
@@ -254,66 +252,14 @@ Uri _resolvePackageUri(Uri uri) {
   return _packageRoot.resolve(uri.path);
 }
 
-// Returns either a file path or a URI starting with http[s]:, as a String.
-String _filePathFromUri(String userUri) {
-  var uri = Uri.parse(userUri);
-  if (_traceLoading) {
-    _log('Getting file path from: $uri');
-  }
-
-  var path;
-  switch (uri.scheme) {
-    case '':
-    case 'file':
-      return uri.toFilePath();
-    case 'package':
-      return _filePathFromUri(_resolvePackageUri(uri).toString());
-    case 'data':
-    case 'http':
-    case 'https':
-      return uri.toString();
-    default:
-      // Only handling file, http, and package URIs
-      // in standalone binary.
-      if (_traceLoading) {
-        _log('Unknown scheme (${uri.scheme}) in $uri.');
-      }
-      throw 'Not a known scheme: $uri';
-  }
-}
-
 // Register callbacks and hooks with the rest of the core libraries.
 @pragma("vm:entry-point")
 _setupHooks() {
   _setupCompleted = true;
-  VMLibraryHooks.resourceReadAsBytes = _resourceReadAsBytes;
-
-  VMLibraryHooks.packageRootUriFuture = _getPackageRootFuture;
   VMLibraryHooks.packageConfigUriFuture = _getPackageConfigFuture;
   VMLibraryHooks.resolvePackageUriFuture = _resolvePackageUriFuture;
 }
 
-// Handling of Resource class by dispatching to the load port.
-Future<List<int>> _resourceReadAsBytes(Uri uri) async {
-  List response =
-      await _makeLoaderRequest<List<int>>(_Dart_kResourceLoad, uri.toString());
-  if (response[4] is String) {
-    // Throw the error.
-    throw response[4];
-  } else {
-    return response[4];
-  }
-}
-
-// TODO(mfairhurst): remove this
-Future<Uri> _getPackageRootFuture() {
-  if (_traceLoading) {
-    _log("Request for package root from user code.");
-  }
-  // Return null, as the `packages/` directory is not supported in dart 2.
-  return new Future.value(null);
-}
-
 Future<Uri> _getPackageConfigFuture() {
   if (_traceLoading) {
     _log("Request for package config from user code.");

sdk/lib/_internal/vm/lib/isolate_patch.dart

@@ -327,11 +327,7 @@ class Isolate {
 
   @patch
   static Future<Uri> get packageRoot {
-    var hook = VMLibraryHooks.packageRootUriFuture;
-    if (hook == null) {
-      throw new UnsupportedError("Isolate.packageRoot");
-    }
-    return hook();
+    return null;
   }
 
   @patch

sdk_nnbd/lib/_internal/vm/bin/builtin.dart

@@ -47,8 +47,6 @@ int _isolateId;
 // Requests made to the service isolate over the load port.
 
 // Extra requests. Keep these in sync between loader.dart and builtin.dart.
-const _Dart_kResourceLoad = 5; // Resource class support.
-const _Dart_kGetPackageRootUri = 6; // Uri of the packages/ directory.
 const _Dart_kGetPackageConfigUri = 7; // Uri of the .packages file.
 const _Dart_kResolvePackageUri = 8; // Resolve a package: uri.
 
@@ -254,66 +252,14 @@ Uri _resolvePackageUri(Uri uri) {
   return _packageRoot.resolve(uri.path);
 }
 
-// Returns either a file path or a URI starting with http[s]:, as a String.
-String _filePathFromUri(String userUri) {
-  var uri = Uri.parse(userUri);
-  if (_traceLoading) {
-    _log('Getting file path from: $uri');
-  }
-
-  var path;
-  switch (uri.scheme) {
-    case '':
-    case 'file':
-      return uri.toFilePath();
-    case 'package':
-      return _filePathFromUri(_resolvePackageUri(uri).toString());
-    case 'data':
-    case 'http':
-    case 'https':
-      return uri.toString();
-    default:
-      // Only handling file, http, and package URIs
-      // in standalone binary.
-      if (_traceLoading) {
-        _log('Unknown scheme (${uri.scheme}) in $uri.');
-      }
-      throw 'Not a known scheme: $uri';
-  }
-}
-
 // Register callbacks and hooks with the rest of the core libraries.
 @pragma("vm:entry-point")
 _setupHooks() {
   _setupCompleted = true;
-  VMLibraryHooks.resourceReadAsBytes = _resourceReadAsBytes;
-
-  VMLibraryHooks.packageRootUriFuture = _getPackageRootFuture;
   VMLibraryHooks.packageConfigUriFuture = _getPackageConfigFuture;
   VMLibraryHooks.resolvePackageUriFuture = _resolvePackageUriFuture;
 }
 
-// Handling of Resource class by dispatching to the load port.
-Future<List<int>> _resourceReadAsBytes(Uri uri) async {
-  List response =
-      await _makeLoaderRequest<List<int>>(_Dart_kResourceLoad, uri.toString());
-  if (response[4] is String) {
-    // Throw the error.
-    throw response[4];
-  } else {
-    return response[4];
-  }
-}
-
-// TODO(mfairhurst): remove this
-Future<Uri> _getPackageRootFuture() {
-  if (_traceLoading) {
-    _log("Request for package root from user code.");
-  }
-  // Return null, as the `packages/` directory is not supported in dart 2.
-  return new Future.value(null);
-}
-
 Future<Uri> _getPackageConfigFuture() {
   if (_traceLoading) {
     _log("Request for package config from user code.");

sdk_nnbd/lib/_internal/vm/lib/isolate_patch.dart

@@ -327,11 +327,7 @@ class Isolate {
 
   @patch
   static Future<Uri> get packageRoot {
-    var hook = VMLibraryHooks.packageRootUriFuture;
-    if (hook == null) {
-      throw new UnsupportedError("Isolate.packageRoot");
-    }
-    return hook();
+    return null;
   }
 
   @patch