Add optional OnAnchor method to EventHandler (#530)

ref #110

include/yaml-cpp/eventhandler.h

@@ -34,7 +34,12 @@ class EventHandler {
   virtual void OnMapStart(const Mark& mark, const std::string& tag,
                           anchor_t anchor, EmitterStyle::value style) = 0;
   virtual void OnMapEnd() = 0;
+
+  virtual void OnAnchor(const Mark& /*mark*/,
+                        const std::string& /*anchor_name*/) {
+    // empty default implementation for compatibility
+  }
 };
-}
+}  // namespace YAML
 
 #endif  // EVENTHANDLER_H_62B23520_7C8E_11DE_8A39_0800200C9A66

src/singledocparser.cpp

@@ -71,8 +71,12 @@ void SingleDocParser::HandleNode(EventHandler& eventHandler) {
   }
 
   std::string tag;
+  std::string anchor_name;
   anchor_t anchor;
-  ParseProperties(tag, anchor);
+  ParseProperties(tag, anchor, anchor_name);
+
+  if (!anchor_name.empty())
+    eventHandler.OnAnchor(mark, anchor_name);
 
   const Token& token = m_scanner.peek();
 
@@ -356,8 +360,10 @@ void SingleDocParser::HandleCompactMapWithNoKey(EventHandler& eventHandler) {
 
 // ParseProperties
 // . Grabs any tag or anchor tokens and deals with them.
-void SingleDocParser::ParseProperties(std::string& tag, anchor_t& anchor) {
+void SingleDocParser::ParseProperties(std::string& tag, anchor_t& anchor,
+                                      std::string& anchor_name) {
   tag.clear();
+  anchor_name.clear();
   anchor = NullAnchor;
 
   while (1) {
@@ -369,7 +375,7 @@ void SingleDocParser::ParseProperties(std::string& tag, anchor_t& anchor) {
         ParseTag(tag);
         break;
       case Token::ANCHOR:
-        ParseAnchor(anchor);
+        ParseAnchor(anchor, anchor_name);
         break;
       default:
         return;
@@ -387,11 +393,12 @@ void SingleDocParser::ParseTag(std::string& tag) {
   m_scanner.pop();
 }
 
-void SingleDocParser::ParseAnchor(anchor_t& anchor) {
+void SingleDocParser::ParseAnchor(anchor_t& anchor, std::string& anchor_name) {
   Token& token = m_scanner.peek();
   if (anchor)
     throw ParserException(token.mark, ErrorMsg::MULTIPLE_ANCHORS);
 
+  anchor_name = token.value;
   anchor = RegisterAnchor(token.value);
   m_scanner.pop();
 }
@@ -411,4 +418,4 @@ anchor_t SingleDocParser::LookupAnchor(const Mark& mark,
 
   return it->second;
 }
-}
+}  // namespace YAML

src/singledocparser.h

@@ -43,9 +43,10 @@ class SingleDocParser : private noncopyable {
   void HandleCompactMap(EventHandler& eventHandler);
   void HandleCompactMapWithNoKey(EventHandler& eventHandler);
 
-  void ParseProperties(std::string& tag, anchor_t& anchor);
+  void ParseProperties(std::string& tag, anchor_t& anchor,
+                       std::string& anchor_name);
   void ParseTag(std::string& tag);
-  void ParseAnchor(anchor_t& anchor);
+  void ParseAnchor(anchor_t& anchor, std::string& anchor_name);
 
   anchor_t RegisterAnchor(const std::string& name);
   anchor_t LookupAnchor(const Mark& mark, const std::string& name) const;
@@ -60,6 +61,6 @@ class SingleDocParser : private noncopyable {
 
   anchor_t m_curAnchor;
 };
-}
+}  // namespace YAML
 
 #endif  // SINGLEDOCPARSER_H_62B23520_7C8E_11DE_8A39_0800200C9A66

test/create-emitter-tests.py

@@ -35,10 +35,12 @@ def doc_end(implicit=False):
 
 def scalar(value, tag='', anchor='', anchor_id=0):
     emit = []
+    handle = []
     if tag:
         emit += ['VerbatimTag("%s")' % encode(tag)]
     if anchor:
         emit += ['Anchor("%s")' % encode(anchor)]
+        handle += ['OnAnchor(_, "%s")' % encode(anchor)]
     if tag:
         out_tag = encode(tag)
     else:
@@ -47,39 +49,46 @@ def scalar(value, tag='', anchor='', anchor_id=0):
         else:
             out_tag = '!'
     emit += ['"%s"' % encode(value)]
-    return {'emit': emit, 'handle': 'OnScalar(_, "%s", %s, "%s")' % (out_tag, anchor_id, encode(value))}
+    handle += ['OnScalar(_, "%s", %s, "%s")' % (out_tag, anchor_id, encode(value))]
+    return {'emit': emit, 'handle': handle}
 
 def comment(value):
     return {'emit': 'Comment("%s")' % value, 'handle': ''}
 
 def seq_start(tag='', anchor='', anchor_id=0, style='_'):
     emit = []
+    handle = []
     if tag:
         emit += ['VerbatimTag("%s")' % encode(tag)]
     if anchor:
         emit += ['Anchor("%s")' % encode(anchor)]
+        handle += ['OnAnchor(_, "%s")' % encode(anchor)]
     if tag:
         out_tag = encode(tag)
     else:
         out_tag = '?'
     emit += ['BeginSeq']
-    return {'emit': emit, 'handle': 'OnSequenceStart(_, "%s", %s, %s)' % (out_tag, anchor_id, style)}
+    handle += ['OnSequenceStart(_, "%s", %s, %s)' % (out_tag, anchor_id, style)]
+    return {'emit': emit, 'handle': handle}
 
 def seq_end():
     return {'emit': 'EndSeq', 'handle': 'OnSequenceEnd()'}
 
 def map_start(tag='', anchor='', anchor_id=0, style='_'):
     emit = []
+    handle = []
     if tag:
         emit += ['VerbatimTag("%s")' % encode(tag)]
     if anchor:
         emit += ['Anchor("%s")' % encode(anchor)]
+        handle += ['OnAnchor(_, "%s")' % encode(anchor)]
     if tag:
         out_tag = encode(tag)
     else:
         out_tag = '?'
     emit += ['BeginMap']
-    return {'emit': emit, 'handle': 'OnMapStart(_, "%s", %s, %s)' % (out_tag, anchor_id, style)}
+    handle += ['OnMapStart(_, "%s", %s, %s)' % (out_tag, anchor_id, style)]
+    return {'emit': emit, 'handle': handle}
 
 def map_end():
     return {'emit': 'EndMap', 'handle': 'OnMapEnd()'}
@@ -202,7 +211,10 @@ def create_emitter_tests(out):
                     out.writeln('')
                     for event in test['events']:
                         handle = event['handle']
-                        if handle:
+                        if isinstance(handle, list):
+                            for e in handle:
+                                out.writeln('EXPECT_CALL(handler, %s);' % e)
+                        elif handle:
                             out.writeln('EXPECT_CALL(handler, %s);' % handle)
                     out.writeln('Parse(out.c_str());')
                 out.writeln('')

test/integration/handler_spec_test.cpp

@@ -199,6 +199,7 @@ TEST_F(HandlerSpecTest, Ex2_10_SimpleAnchor) {
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "hr"));
   EXPECT_CALL(handler, OnSequenceStart(_, "?", 0, EmitterStyle::Block));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "Mark McGwire"));
+  EXPECT_CALL(handler, OnAnchor(_, "SS"));
   EXPECT_CALL(handler, OnScalar(_, "?", 1, "Sammy Sosa"));
   EXPECT_CALL(handler, OnSequenceEnd());
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "rbi"));
@@ -376,6 +377,7 @@ TEST_F(HandlerSpecTest, Ex2_24_GlobalTags) {
   EXPECT_CALL(handler, OnMapStart(_, "tag:clarkevans.com,2002:circle", 0,
                                   EmitterStyle::Block));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "center"));
+  EXPECT_CALL(handler, OnAnchor(_, "ORIGIN"));
   EXPECT_CALL(handler, OnMapStart(_, "?", 1, EmitterStyle::Flow));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "x"));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "73"));
@@ -456,6 +458,7 @@ TEST_F(HandlerSpecTest, Ex2_27_Invoice) {
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "date"));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "2001-01-23"));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "bill-to"));
+  EXPECT_CALL(handler, OnAnchor(_, "id001"));
   EXPECT_CALL(handler, OnMapStart(_, "?", 1, EmitterStyle::Block));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "given"));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "Chris"));
@@ -616,6 +619,7 @@ TEST_F(HandlerSpecTest, Ex5_6_NodePropertyIndicators) {
   EXPECT_CALL(handler, OnDocumentStart(_));
   EXPECT_CALL(handler, OnMapStart(_, "?", 0, EmitterStyle::Block));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "anchored"));
+  EXPECT_CALL(handler, OnAnchor(_, "anchor"));
   EXPECT_CALL(handler, OnScalar(_, "!local", 1, "value"));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "alias"));
   EXPECT_CALL(handler, OnAlias(_, 1));
@@ -909,8 +913,10 @@ TEST_F(HandlerSpecTest, Ex6_22_GlobalTagPrefix) {
 TEST_F(HandlerSpecTest, Ex6_23_NodeProperties) {
   EXPECT_CALL(handler, OnDocumentStart(_));
   EXPECT_CALL(handler, OnMapStart(_, "?", 0, EmitterStyle::Block));
+  EXPECT_CALL(handler, OnAnchor(_, "a1"));
   EXPECT_CALL(handler, OnScalar(_, "tag:yaml.org,2002:str", 1, "foo"));
   EXPECT_CALL(handler, OnScalar(_, "tag:yaml.org,2002:str", 0, "bar"));
+  EXPECT_CALL(handler, OnAnchor(_, "a2"));
   EXPECT_CALL(handler, OnScalar(_, "?", 2, "baz"));
   EXPECT_CALL(handler, OnAlias(_, 1));
   EXPECT_CALL(handler, OnMapEnd());
@@ -972,6 +978,7 @@ TEST_F(HandlerSpecTest, Ex6_29_NodeAnchors) {
   EXPECT_CALL(handler, OnDocumentStart(_));
   EXPECT_CALL(handler, OnMapStart(_, "?", 0, EmitterStyle::Block));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "First occurrence"));
+  EXPECT_CALL(handler, OnAnchor(_, "anchor"));
   EXPECT_CALL(handler, OnScalar(_, "?", 1, "Value"));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "Second occurrence"));
   EXPECT_CALL(handler, OnAlias(_, 1));
@@ -984,10 +991,12 @@ TEST_F(HandlerSpecTest, Ex7_1_AliasNodes) {
   EXPECT_CALL(handler, OnDocumentStart(_));
   EXPECT_CALL(handler, OnMapStart(_, "?", 0, EmitterStyle::Block));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "First occurrence"));
+  EXPECT_CALL(handler, OnAnchor(_, "anchor"));
   EXPECT_CALL(handler, OnScalar(_, "?", 1, "Foo"));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "Second occurrence"));
   EXPECT_CALL(handler, OnAlias(_, 1));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "Override anchor"));
+  EXPECT_CALL(handler, OnAnchor(_, "anchor"));
   EXPECT_CALL(handler, OnScalar(_, "?", 2, "Bar"));
   EXPECT_CALL(handler, OnScalar(_, "?", 0, "Reuse anchor"));
   EXPECT_CALL(handler, OnAlias(_, 2));
@@ -1307,6 +1316,7 @@ TEST_F(HandlerSpecTest, Ex7_24_FlowNodes) {
   EXPECT_CALL(handler, OnSequenceStart(_, "?", 0, EmitterStyle::Block));
   EXPECT_CALL(handler, OnScalar(_, "tag:yaml.org,2002:str", 0, "a"));
   EXPECT_CALL(handler, OnScalar(_, "!", 0, "b"));
+  EXPECT_CALL(handler, OnAnchor(_, "anchor"));
   EXPECT_CALL(handler, OnScalar(_, "!", 1, "c"));
   EXPECT_CALL(handler, OnAlias(_, 1));
   EXPECT_CALL(handler, OnScalar(_, "tag:yaml.org,2002:str", 0, ""));
@@ -1607,5 +1617,5 @@ TEST_F(HandlerSpecTest, Ex8_22_BlockCollectionNodes) {
   EXPECT_CALL(handler, OnDocumentEnd());
   Parse(ex8_22);
 }
-}
-}
+}  // namespace
+}  // namespace YAML

test/mock_event_handler.h

@@ -22,5 +22,6 @@ class MockEventHandler : public EventHandler {
   MOCK_METHOD4(OnMapStart, void(const Mark&, const std::string&, anchor_t,
                                 EmitterStyle::value));
   MOCK_METHOD0(OnMapEnd, void());
+  MOCK_METHOD2(OnAnchor, void(const Mark&, const std::string&));
 };
-}
+}  // namespace YAML