Task: Build Library Element Model

pkg/analyzer/lib/src/task/dart.dart

Index: pkg/analyzer/lib/src/task/dart.dart
diff --git a/pkg/analyzer/lib/src/task/dart.dart b/pkg/analyzer/lib/src/task/dart.dart
index 5fd3c1dbf3227d3a828005f644ab53b0c30f6aa1..9b8ca0b06db1ffad5f96024d3a317ff62fc01e3a 100644
--- a/pkg/analyzer/lib/src/task/dart.dart
+++ b/pkg/analyzer/lib/src/task/dart.dart
@@ -14,8 +14,10 @@ import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/parser.dart';
 import 'package:analyzer/src/generated/resolver.dart';
 import 'package:analyzer/src/generated/scanner.dart';
+import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/task/general.dart';
+import 'package:analyzer/src/task/inputs.dart';
 import 'package:analyzer/task/dart.dart';
 import 'package:analyzer/task/general.dart';
 import 'package:analyzer/task/model.dart';
@@ -86,6 +88,263 @@ class BuildCompilationUnitElementTask extends SourceBasedAnalysisTask {
 }
 
 /**
+ * A task that builds a library element for a Dart library.
+ */
+class BuildLibraryElementTask extends SourceBasedAnalysisTask {
+  /**
+   * The name of the input whose value is the built compilation unit of the
+   * defining compilation unit of a library.
+   */
+  static const String DEFINING_BUILT_UNIT_INPUT_NAME = 'definingBuiltUnit';
+
+  /**
+   * The name of the input whose value is a list of built compilation units
+   * of the parts sourced by a library.
+   */
+  static const String PART_BUILT_UNITS_INPUT_NAME = 'partBuiltUnits';
+
+  /**
+   * The name of the function used as an entry point.
+   */
+  static const String ENTRY_POINT_NAME = "main";
+
+  /**
+   * The task descriptor describing this kind of task.
+   */
+  static final TaskDescriptor DESCRIPTOR = new TaskDescriptor(
+      'BUILD_LIBRARY_ELEMENT', createTask, buildInputs, <ResultDescriptor>[
+    BUILD_LIBRARY_ERRORS,
+    BUILT_LIBRARY_ELEMENT,
+    IS_LAUNCHABLE,
+    HAS_HTML_IMPORT
+  ]);
+
+  /**
+   * Initialize a newly created task to build a library element for the given
+   * [target] in the given [context].
+   */
+  BuildLibraryElementTask(
+      InternalAnalysisContext context, AnalysisTarget target)
+      : super(context, target);
+
+  @override
+  TaskDescriptor get descriptor => DESCRIPTOR;
+
+  @override
+  void internalPerform() {
+    List<AnalysisError> errors = <AnalysisError>[];
+    //
+    // Prepare inputs.
+    //
+    Source librarySource = getRequiredSource();
+    CompilationUnit definingCompilationUnit =
+        getRequiredInput(DEFINING_BUILT_UNIT_INPUT_NAME);
+    List<CompilationUnit> partUnits =
+        getRequiredInput(PART_BUILT_UNITS_INPUT_NAME);
+    //
+    // Process inputs.
+    //
+    CompilationUnitElementImpl definingCompilationUnitElement =
+        definingCompilationUnit.element;
+    Map<Source, CompilationUnit> partUnitMap =
+        new HashMap<Source, CompilationUnit>();
+    for (CompilationUnit partUnit in partUnits) {
+      Source partSource = partUnit.element.source;
+      partUnitMap[partSource] = partUnit;
+    }
+    Source htmlSource = context.sourceFactory.forUri(DartSdk.DART_HTML);
+    //
+    // Update "part" directives.
+    //
+    LibraryIdentifier libraryNameNode = null;
+    bool hasHtmlImport = false;
+    bool hasPartDirective = false;
+    FunctionElement entryPoint =
+        _findEntryPoint(definingCompilationUnitElement);
+    List<Directive> directivesToResolve = <Directive>[];
+    List<CompilationUnitElementImpl> sourcedCompilationUnits =
+        <CompilationUnitElementImpl>[];
+    for (Directive directive in definingCompilationUnit.directives) {
+      if (directive is ImportDirective) {
+        hasHtmlImport = hasHtmlImport || directive.source == htmlSource;
+      } else if (directive is LibraryDirective) {
+        if (libraryNameNode == null) {
+          libraryNameNode = directive.name;
+          directivesToResolve.add(directive);
+        }
+      } else if (directive is PartDirective) {
+        PartDirective partDirective = directive;
+        StringLiteral partUri = partDirective.uri;
+        Source partSource = partDirective.source;
+        if (context.exists(partSource)) {
+          hasPartDirective = true;
+          CompilationUnit partUnit = partUnitMap[partSource];
+          CompilationUnitElementImpl partElement = partUnit.element;
+          partElement.uriOffset = partUri.offset;
+          partElement.uriEnd = partUri.end;
+          partElement.uri = partDirective.uriContent;
+          //
+          // Validate that the part contains a part-of directive with the same
+          // name as the library.
+          //
+          String partLibraryName =
+              _getPartLibraryName(partSource, partUnit, directivesToResolve);
+          if (partLibraryName == null) {
+            errors.add(new AnalysisError.con2(librarySource, partUri.offset,
+                partUri.length, CompileTimeErrorCode.PART_OF_NON_PART, [
+              partUri.toSource()
+            ]));
+          } else if (libraryNameNode == null) {
+            // TODO(brianwilkerson) Collect the names declared by the part.
+            // If they are all the same then we can use that name as the
+            // inferred name of the library and present it in a quick-fix.
+            // partLibraryNames.add(partLibraryName);
+          } else if (libraryNameNode.name != partLibraryName) {
+            errors.add(new AnalysisError.con2(librarySource, partUri.offset,
+                partUri.length, StaticWarningCode.PART_OF_DIFFERENT_LIBRARY, [
+              libraryNameNode.name,
+              partLibraryName
+            ]));
+          }
+          if (entryPoint == null) {
+            entryPoint = _findEntryPoint(partElement);
+          }
+          directive.element = partElement;
+          sourcedCompilationUnits.add(partElement);
+        }
+      }
+    }
+    if (hasPartDirective && libraryNameNode == null) {
+      errors.add(new AnalysisError.con1(librarySource,
+          ResolverErrorCode.MISSING_LIBRARY_DIRECTIVE_WITH_PART));
+    }
+    //
+    // Create and populate the library element.
+    //
+    LibraryElementImpl libraryElement =
+        new LibraryElementImpl.forNode(context, libraryNameNode);
+    libraryElement.definingCompilationUnit = definingCompilationUnitElement;
+    libraryElement.entryPoint = entryPoint;
+    libraryElement.parts = sourcedCompilationUnits;
+    for (Directive directive in directivesToResolve) {
+      directive.element = libraryElement;
+    }
+    if (sourcedCompilationUnits.isNotEmpty) {
+      _patchTopLevelAccessors(libraryElement);
+    }
+    //
+    // Record outputs.
+    //
+    outputs[BUILD_LIBRARY_ERRORS] = errors;
+    outputs[BUILT_LIBRARY_ELEMENT] = libraryElement;
+    outputs[IS_LAUNCHABLE] = entryPoint != null;
+    outputs[HAS_HTML_IMPORT] = hasHtmlImport;
+  }
+
+  /**
+   * Add all of the non-synthetic [getters] and [setters] defined in the given
+   * [unit] that have no corresponding accessor to one of the given collections.
+   */
+  void _collectAccessors(Map<String, PropertyAccessorElement> getters,
+      List<PropertyAccessorElement> setters, CompilationUnitElement unit) {
+    for (PropertyAccessorElement accessor in unit.accessors) {
+      if (accessor.isGetter) {
+        if (!accessor.isSynthetic && accessor.correspondingSetter == null) {
+          getters[accessor.displayName] = accessor;
+        }
+      } else {
+        if (!accessor.isSynthetic && accessor.correspondingGetter == null) {
+          setters.add(accessor);
+        }
+      }
+    }
+  }
+
+  /**
+   * Return the top-level [FunctionElement] entry point, or `null` if the given
+   * [element] does not define an entry point.
+   */
+  FunctionElement _findEntryPoint(CompilationUnitElementImpl element) {
+    for (FunctionElement function in element.functions) {
+      if (function.name == ENTRY_POINT_NAME) {
+        return function;
+      }
+    }
+    return null;
+  }
+
+  /**
+   * Return the name of the library that the given part is declared to be a
+   * part of, or `null` if the part does not contain a part-of directive.
+   */
+  String _getPartLibraryName(Source partSource, CompilationUnit partUnit,
+      List<Directive> directivesToResolve) {
+    for (Directive directive in partUnit.directives) {
+      if (directive is PartOfDirective) {
+        directivesToResolve.add(directive);
+        LibraryIdentifier libraryName = directive.libraryName;
+        if (libraryName != null) {
+          return libraryName.name;
+        }
+      }
+    }
+    return null;
+  }
+
+  /**
+   * Look through all of the compilation units defined for the given [library],
+   * looking for getters and setters that are defined in different compilation
+   * units but that have the same names. If any are found, make sure that they
+   * have the same variable element.
+   */
+  void _patchTopLevelAccessors(LibraryElementImpl library) {
+    HashMap<String, PropertyAccessorElement> getters =
+        new HashMap<String, PropertyAccessorElement>();
+    List<PropertyAccessorElement> setters = <PropertyAccessorElement>[];
+    _collectAccessors(getters, setters, library.definingCompilationUnit);
+    for (CompilationUnitElement unit in library.parts) {
+      _collectAccessors(getters, setters, unit);
+    }
+    for (PropertyAccessorElementImpl setter in setters) {
+      PropertyAccessorElement getter = getters[setter.displayName];
+      if (getter != null) {
+        TopLevelVariableElementImpl variable = getter.variable;
+        TopLevelVariableElementImpl setterVariable = setter.variable;
+        CompilationUnitElementImpl setterUnit = setterVariable.enclosingElement;
+        setterUnit.replaceTopLevelVariable(setterVariable, variable);
+        variable.setter = setter;
+        setter.variable = variable;
+      }
+    }
+  }
+
+  /**
+   * Return a map from the names of the inputs of this kind of task to the task
+   * input descriptors describing those inputs for a task with the given
+   * [target].
+   */
+  static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
+    return <String, TaskInput>{
+      DEFINING_BUILT_UNIT_INPUT_NAME: new SimpleTaskInput(target, BUILT_UNIT),
+      PART_BUILT_UNITS_INPUT_NAME:
+          new ListBasedTaskInput<List<Source>, CompilationUnit>(
+              new SimpleTaskInput<List<Source>>(target, INCLUDED_PARTS),
+              (Source includedSource) => new SimpleTaskInput<CompilationUnit>(
+                  includedSource, BUILT_UNIT))
+    };
+  }
+
+  /**
+   * Create a [BuildLibraryElementTask] based on the given [target] in the
+   * given [context].
+   */
+  static BuildLibraryElementTask createTask(
+      AnalysisContext context, AnalysisTarget target) {
+    return new BuildLibraryElementTask(context, target);
+  }
+}
+
+/**
  * A task that parses the content of a Dart file, producing an AST structure.
  */
 class ParseDartTask extends SourceBasedAnalysisTask {