Add an "api signature" to summaries.

pkg/analyzer/tool/summary/generate.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /**
  * This file contains code to generate serialization/deserialization logic for
  * summaries based on an "IDL" description of the summary format (written in
  * stylized Dart).
  *
  * For each class in the "IDL" input, two corresponding classes are generated:
@@ skipping 600 matching lines @@
               if (fieldType.isList) {
                 out('$valueName?.forEach((b) => b.flushInformative());');
               } else {
                 out('$valueName?.flushInformative();');
               }
             }
           }
         });
         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();
         out('List<int> toBuffer() {');
         indent(() {
           out('fb.Builder fbBuilder = new fb.Builder();');
           String fileId = cls.fileIdentifier == null
               ? ''
               : ', ${quoted(cls.fileIdentifier)}';
           out('return fbBuilder.finish(finish(fbBuilder)$fileId);');
@@ skipping 182 matching lines @@
         assert(readCode != null);
         // Write the getter implementation.
         out();
         out('@override');
         String returnType = dartType(type);
         if (field.isDeprecated) {
           out('$returnType get $fieldName => $_throwDeprecated;');
         } else {
           out('$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;');
           });
           out('}');
         }
       }
     });
     out('}');
   }
 
@@ skipping 77 matching lines @@
     String name = cls.name;
     out('${idlPrefix(name)} read$name(List<int> buffer) {');
     indent(() {
       out('fb.BufferContext rootRef = new fb.BufferContext.fromBytes(buffer);');
       out('return const _${name}Reader().read(rootRef, 0);');
     });
     out('}');
   }
 
   /**
+   * 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.
    */
   String _getNodeDoc(LineInfo lineInfo, AnnotatedNode node) {
     Comment comment = node.documentationComment;
     if (comment != null &&
         comment.isDocumentation &&
         comment.tokens.length == 1 &&
         comment.tokens.first.type == TokenType.MULTI_LINE_COMMENT) {
       Token token = comment.tokens.first;
       int column = lineInfo.getLocation(token.offset).columnNumber;
       String indent = ' ' * (column - 1);
       return token.lexeme.split('\n').map((String line) {
         if (line.startsWith(indent)) {
           line = line.substring(indent.length);
         }
         return line;
       }).join('\n');
     }
     return null;
   }
 }