Add an "api signature" to summaries.

pkg/analyzer/tool/summary/generate.dart

Index: pkg/analyzer/tool/summary/generate.dart
diff --git a/pkg/analyzer/tool/summary/generate.dart b/pkg/analyzer/tool/summary/generate.dart
index 869b38de43abbfc5f4b37d5460a53deffc194010..39d0b99b91e5253c715d607e687afcf48668a5a7 100644
--- a/pkg/analyzer/tool/summary/generate.dart
+++ b/pkg/analyzer/tool/summary/generate.dart
@@ -618,6 +618,44 @@ class _CodeGenerator {
         });
         out('}');
       }
+      // Generate collectApiSignature().
+      {
+        out();
+        out('/**');
+        out(' * Accumulate non-[informative] data into [signature].');
+        out(' */');
+        out('void collectApiSignature(fb.ApiSignature signature) {');
+        indent(() {
+          List<idlModel.FieldDeclaration> sortedFields = cls.fields.toList()
+            ..sort((idlModel.FieldDeclaration a, idlModel.FieldDeclaration b) =>
+                a.id.compareTo(b.id));
+          for (idlModel.FieldDeclaration field in sortedFields) {
+            if (field.isInformative) {
+              continue;
+            }
+            String ref = 'this._${field.name}';
+            if (field.type.isList) {
+              out('if ($ref == null) {');
+              indent(() {
+                out('signature.addInt(0);');
+              });
+              out('} else {');
+              indent(() {
+                out('signature.addInt($ref.length);');
+                out('for (var x in $ref) {');
+                indent(() {
+                  _generateSignatureCall(field.type.typeName, 'x', false);
+                });
+                out('}');
+              });
+              out('}');
+            } else {
+              _generateSignatureCall(field.type.typeName, ref, true);
+            }
+          }
+        });
+        out('}');
+      }
       // Generate finish.
       if (cls.isTopLevel) {
         out();
@@ -820,7 +858,8 @@ class _CodeGenerator {
         } else {
           out('$returnType get $fieldName {');
           indent(() {
-            String readExpr = '$readCode.vTableGet(_bc, _bcOffset, $index, $def)';
+            String readExpr =
+                '$readCode.vTableGet(_bc, _bcOffset, $index, $def)';
             out('_$fieldName ??= $readExpr;');
             out('return _$fieldName;');
           });
@@ -918,6 +957,56 @@ class _CodeGenerator {
   }
 
   /**
+   * Generate a call to the appropriate method of [ApiSignature] for the type
+   * [typeName], using the data named by [ref].  If [couldBeNull] is `true`,
+   * generate code to handle the possibility that [ref] is `null` (substituting
+   * in the appropriate default value).
+   */
+  void _generateSignatureCall(String typeName, String ref, bool couldBeNull) {
+    if (_idl.enums.containsKey(typeName)) {
+      if (couldBeNull) {
+        out('signature.addInt($ref == null ? 0 : $ref.index);');
+      } else {
+        out('signature.addInt($ref.index);');
+      }
+    } else if (_idl.classes.containsKey(typeName)) {
+      if (couldBeNull) {
+        out('signature.addBool($ref != null);');
+      }
+      out('$ref?.collectApiSignature(signature);');
+    } else {
+      switch (typeName) {
+        case 'String':
+          if (couldBeNull) {
+            ref += " ?? ''";
+          }
+          out("signature.addString($ref);");
+          break;
+        case 'int':
+          if (couldBeNull) {
+            ref += ' ?? 0';
+          }
+          out('signature.addInt($ref);');
+          break;
+        case 'bool':
+          if (couldBeNull) {
+            ref += ' == true';
+          }
+          out('signature.addBool($ref);');
+          break;
+        case 'double':
+          if (couldBeNull) {
+            ref += ' ?? 0.0';
+          }
+          out('signature.addDouble($ref);');
+          break;
+        default:
+          throw "Don't know how to generate signature call for $typeName";
+      }
+    }
+  }
+
+  /**
    * Return the documentation text of the given [node], or `null` if the [node]
    * does not have a comment.  Each line is `\n` separated.
    */