Store parts in Kernel Library, resynthesize parts in Analyzer.

pkg/kernel/lib/ast.dart

Index: pkg/kernel/lib/ast.dart
diff --git a/pkg/kernel/lib/ast.dart b/pkg/kernel/lib/ast.dart
index 93fcd5c882380fb5d00ed69cc32f1db3978b8ba0..76c28cd75e0b694f9ecb2ea5eabbd89c73951e01 100644
--- a/pkg/kernel/lib/ast.dart
+++ b/pkg/kernel/lib/ast.dart
@@ -269,6 +269,8 @@ class Library extends NamedNode implements Comparable<Library> {
   String name;
   final List<Expression> annotations;
   final List<LibraryDependency> dependencies;
+  @informative
+  final List<LibraryPart> parts;
   final List<Typedef> typedefs;
   final List<Class> classes;
   final List<Procedure> procedures;
@@ -279,6 +281,7 @@ class Library extends NamedNode implements Comparable<Library> {
       this.isExternal: false,
       List<Expression> annotations,
       List<LibraryDependency> dependencies,
+      List<LibraryPart> parts,
       List<Typedef> typedefs,
       List<Class> classes,
       List<Procedure> procedures,
@@ -287,12 +290,14 @@ class Library extends NamedNode implements Comparable<Library> {
       Reference reference})
       : this.annotations = annotations ?? <Expression>[],
         this.dependencies = dependencies ?? <LibraryDependency>[],
+        this.parts = parts ?? <LibraryPart>[],
         this.typedefs = typedefs ?? <Typedef>[],
         this.classes = classes ?? <Class>[],
         this.procedures = procedures ?? <Procedure>[],
         this.fields = fields ?? <Field>[],
         super(reference) {
     setParents(this.dependencies, this);
+    setParents(this.parts, this);
     setParents(this.typedefs, this);
     setParents(this.classes, this);
     setParents(this.procedures, this);
@@ -353,10 +358,15 @@ class Library extends NamedNode implements Comparable<Library> {
     dependencies.add(node..parent = this);
   }
 
+  void addPart(LibraryPart node) {
+    parts.add(node..parent = this);
+  }
+
   accept(TreeVisitor v) => v.visitLibrary(this);
 
   visitChildren(Visitor v) {
     visitList(dependencies, v);
+    visitList(parts, v);
     visitList(typedefs, v);
     visitList(classes, v);
     visitList(procedures, v);
@@ -365,6 +375,7 @@ class Library extends NamedNode implements Comparable<Library> {
 
   transformChildren(Transformer v) {
     transformList(dependencies, v, this);
+    transformList(parts, v, this);
     transformList(typedefs, v, this);
     transformList(classes, v, this);
     transformList(procedures, v, this);
@@ -463,6 +474,37 @@ class LibraryDependency extends TreeNode {
   }
 }
 
+/// A part declaration in a library.
+///
+///     part <url>;
+///
+/// optionally with metadata.
+class LibraryPart extends TreeNode {
+  final List<Expression> annotations;
+  final String fileUri;
+
+  LibraryPart(List<Expression> annotations, String fileUri)
+      : this.byReference(annotations, fileUri);
+
+  LibraryPart.byReference(this.annotations, this.fileUri) {
+    setParents(annotations, this);
+  }
+
+  void addAnnotation(Expression annotation) {
+    annotations.add(annotation..parent = this);
+  }
+
+  accept(TreeVisitor v) => v.visitLibraryPart(this);
+
+  visitChildren(Visitor v) {
+    visitList(annotations, v);
+  }
+
+  transformChildren(Transformer v) {
+    transformList(annotations, v, this);
+  }
+}
+
 /// A `show` or `hide` clause for an import or export.
 class Combinator extends TreeNode {
   bool isShow;