Instrument analyzer's type analysis and run front_end inference tests.

pkg/analyzer/lib/src/fasta/uri_instrumentation.dart

Index: pkg/analyzer/lib/src/fasta/uri_instrumentation.dart
diff --git a/pkg/analyzer/lib/src/fasta/uri_instrumentation.dart b/pkg/analyzer/lib/src/fasta/uri_instrumentation.dart
new file mode 100644
index 0000000000000000000000000000000000000000..1b7772f1fce298a770fadbcec9f951aa1e84ea85
--- /dev/null
+++ b/pkg/analyzer/lib/src/fasta/uri_instrumentation.dart
@@ -0,0 +1,113 @@
+import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/dart/element/type.dart';
+import 'package:front_end/src/base/instrumentation.dart'
+    show Instrumentation, InstrumentationValue;
+
+/**
+ * Instance of [InstrumentationValue] describing a [DartType].
+ */
+class InstrumentationValueForType extends InstrumentationValue {
+  final DartType type;
+
+  InstrumentationValueForType(this.type);
+
+  @override
+  String toString() {
+    StringBuffer buffer = new StringBuffer();
+    _appendType(buffer, type);
+    return buffer.toString();
+  }
+
+  void _appendElementName(StringBuffer buffer, Element element) {
+    String name = element.name;
+    String libraryName = element.library.name;
+    if (libraryName == '') {
+      throw new StateError('The element $name must be in a named library.');
+    }
+    if (libraryName != 'dart.core' &&
+        libraryName != 'dart.async' &&
+        libraryName != 'test') {
+      buffer.write('$libraryName::$name');
+    } else {
+      buffer.write('$name');
+    }
+  }
+
+  void _appendList<T>(StringBuffer buffer, String open, String close,
+      List<T> items, String separator, writeItem(T item),
+      {bool includeEmpty: false}) {
+    if (!includeEmpty && items.isEmpty) {
+      return;
+    }
+    buffer.write(open);
+    bool first = true;
+    for (T item in items) {
+      if (!first) {
+        buffer.write(separator);
+      }
+      writeItem(item);
+      first = false;
+    }
+    buffer.write(close);
+  }
+
+  void _appendParameters(
+      StringBuffer buffer, List<ParameterElement> parameters) {
+    _appendList<ParameterElement>(buffer, '(', ')', parameters, ', ',
+        (parameter) {
+      _appendType(buffer, type);
+      buffer.write(' ');
+      buffer.write(parameter.name);
+    }, includeEmpty: true);
+  }
+
+  void _appendType(StringBuffer buffer, DartType type) {
+    if (type == null) {
+      buffer.write('none');
+    } else if (type is FunctionType) {
+      Element element = type.element;
+      _appendElementName(buffer, element);
+      _appendTypeArguments(buffer, type.typeArguments);
+      _appendParameters(buffer, type.parameters);
+      buffer.write(' → ');
+      _appendType(buffer, type.returnType);
+    } else if (type is InterfaceType) {
+      ClassElement element = type.element;
+      _appendElementName(buffer, element);
+      _appendTypeArguments(buffer, type.typeArguments);
+    } else {
+      buffer.write(type.toString());
+    }
+  }
+
+  void _appendTypeArguments(StringBuffer buffer, List<DartType> typeArguments) {
+    _appendList<DartType>(buffer, '<', '>', typeArguments, ', ',
+        (type) => _appendType(buffer, type));
+  }
+}
+
+/**
+ * Wrapper around [Instrumentation] for writing analyzer specific values
+ * for a single URI.
+ */
+class UriInstrumentation {
+  final Instrumentation _instrumentation;
+  final Uri _uri;
+
+  UriInstrumentation(this._instrumentation, this._uri);
+
+  void recordInference(int offset, DartType type) {
+    _instrumentation.record(
+        _uri, offset, 'type', new InstrumentationValueForType(type));
+  }
+
+  void recordPromotion(int offset, DartType type) {
+    _instrumentation.record(
+        _uri, offset, 'promotedType', new InstrumentationValueForType(type));
+  }
+
+  void recordTopType(int offset, DartType type) {
+    _instrumentation.record(
+        _uri, offset, 'topType', new InstrumentationValueForType(type));
+  }
+}