Fix FasterXML#397 (alas, no unit tests)

# Conflicts:
#	release-notes/VERSION-2.x

Author: cowtowncoder

src/main/java/com/fasterxml/jackson/dataformat/xml/deser/FromXmlParser.java

@@ -462,15 +462,16 @@ public JsonToken nextToken() throws IOException
     {
         JsonToken t = nextToken0();
         if (t != null) {
+            final String loc = _parsingContext.pathAsPointer().toString();
             switch (t) {
             case FIELD_NAME:
-                System.out.println("FromXmlParser.nextToken(): JsonToken.FIELD_NAME '"+_parsingContext.getCurrentName()+"'");
+                System.out.printf("FromXmlParser.nextToken() at '%s': JsonToken.FIELD_NAME '%s'\n", loc, _parsingContext.getCurrentName());
                 break;
             case VALUE_STRING:
-                System.out.println("FromXmlParser.nextToken(): JsonToken.VALUE_STRING '"+getText()+"'");
+                System.out.printf("FromXmlParser.nextToken() at '%s': JsonToken.VALUE_STRING '%s'\n", loc, getText());
                 break;
             default:
-                System.out.println("FromXmlParser.nextToken(): "+t);
+                System.out.printf("FromXmlParser.nextToken() at '%s': %s\n", loc, t);
             }
         }
         return t;
@@ -486,6 +487,7 @@ public JsonToken nextToken() throws IOException
             JsonToken t = _nextToken;
             _currToken = t;
             _nextToken = null;
+
             switch (t) {
             case START_OBJECT:
                 _parsingContext = _parsingContext.createChildObjectContext(-1, -1);
@@ -501,7 +503,9 @@ public JsonToken nextToken() throws IOException
                 _parsingContext.setCurrentName(_xmlTokens.getLocalName());
                 break;
             default: // VALUE_STRING, VALUE_NULL
-                // should be fine as is?
+                // 13-May-2020, tatu: [dataformat-xml#397]: advance `index` anyway; not
+                //    used for Object contexts, updated automatically by "createChildXxxContext"
+                _parsingContext.valueStarted();
             }
             return t;
         }
@@ -564,6 +568,8 @@ public JsonToken nextToken() throws IOException
                     }
                     // 07-Sep-2019, tatu: for [dataformat-xml#353], must NOT return second null
                     if (_currToken != JsonToken.VALUE_NULL) {
+                        // 13-May-2020, tatu: [dataformat-xml#397]: advance `index`
+                        _parsingContext.valueStarted();
                         return (_currToken = JsonToken.VALUE_NULL);
                     }
                 }
@@ -584,6 +590,8 @@ public JsonToken nextToken() throws IOException
                 return (_currToken = JsonToken.FIELD_NAME);
             case XmlTokenStream.XML_ATTRIBUTE_VALUE:
                 _currText = _xmlTokens.getText();
+                // 13-May-2020, tatu: [dataformat-xml#397]: advance `index`
+                _parsingContext.valueStarted();
                 return (_currToken = JsonToken.VALUE_STRING);
             case XmlTokenStream.XML_TEXT:
                 _currText = _xmlTokens.getText();
@@ -666,6 +674,8 @@ public String nextTextValue() throws IOException
 
             // expected case; yes, got a String
             if (t == JsonToken.VALUE_STRING) {
+                // 13-May-2020, tatu: [dataformat-xml#397]: advance `index`
+                _parsingContext.valueStarted();
                 return _currText;
             }
             _updateState(t);
@@ -715,6 +725,8 @@ public String nextTextValue() throws IOException
                 // NOTE: this is different from nextToken() -- produce "", NOT null
                 _mayBeLeaf = false;
                 _currToken = JsonToken.VALUE_STRING;
+                // 13-May-2020, tatu: [dataformat-xml#397]: advance `index`
+                _parsingContext.valueStarted();
                 return (_currText = "");
             }
             _currToken = _parsingContext.inArray() ? JsonToken.END_ARRAY : JsonToken.END_OBJECT;
@@ -735,6 +747,8 @@ public String nextTextValue() throws IOException
             break;
         case XmlTokenStream.XML_ATTRIBUTE_VALUE:
             _currToken = JsonToken.VALUE_STRING;
+            // 13-May-2020, tatu: [dataformat-xml#397]: advance `index`
+            _parsingContext.valueStarted();
             return (_currText = _xmlTokens.getText());
         case XmlTokenStream.XML_TEXT:
             _currText = _xmlTokens.getText();
@@ -748,6 +762,8 @@ public String nextTextValue() throws IOException
                 }
                 // NOTE: this is different from nextToken() -- NO work-around
                 // for otherwise empty List/array
+                // 13-May-2020, tatu: [dataformat-xml#397]: advance `index`
+                _parsingContext.valueStarted();
                 _currToken = JsonToken.VALUE_STRING;
                 return _currText;
             }

src/main/java/com/fasterxml/jackson/dataformat/xml/deser/XmlReadContext.java

@@ -105,6 +105,7 @@ public static XmlReadContext createRootContext() {
 
     public final XmlReadContext createChildArrayContext(int lineNr, int colNr)
     {
+        ++_index; // not needed for Object, but does not hurt so no need to check curr type
         XmlReadContext ctxt = _child;
         if (ctxt == null) {
             _child = ctxt = new XmlReadContext(this, TYPE_ARRAY, lineNr, colNr);
@@ -116,6 +117,7 @@ public final XmlReadContext createChildArrayContext(int lineNr, int colNr)
 
     public final XmlReadContext createChildObjectContext(int lineNr, int colNr)
     {
+        ++_index; // not needed for Object, but does not hurt so no need to check curr type
         XmlReadContext ctxt = _child;
         if (ctxt == null) {
             _child = ctxt = new XmlReadContext(this, TYPE_OBJECT, lineNr, colNr);
@@ -127,7 +129,7 @@ public final XmlReadContext createChildObjectContext(int lineNr, int colNr)
 
     /*
     /**********************************************************
-    /* Abstract method implementation
+    /* Abstract method implementation, overrides
     /**********************************************************
      */
 
@@ -140,18 +142,16 @@ public final XmlReadContext createChildObjectContext(int lineNr, int colNr)
     @Override
     public final XmlReadContext getParent() { return _parent; }
 
-    /*
-    /**********************************************************
-    /* State changes
-    /**********************************************************
+    /**
+     * @return Location pointing to the point where the context
+     *   start marker was found
      */
+    @Override
+    public final JsonLocation getStartLocation(Object srcRef) {
+        // We don't keep track of offsets at this level (only reader does)
+        long totalChars = -1L;
 
-    public final boolean expectComma() {
-        throw new UnsupportedOperationException();
-    }
-
-    public void setCurrentName(String name) {
-        _currentName = name;
+        return new JsonLocation(srcRef, totalChars, _lineNr, _columnNr);
     }
 
     /*
@@ -161,15 +161,17 @@ public void setCurrentName(String name) {
      */
 
     /**
-     * @return Location pointing to the point where the context
-     *   start marker was found
+     * Method called to mark start of new value, mostly to update `index`
+     * for Array and Root contexts.
+     *
+     * @since 2.12
      */
-    @Override
-    public final JsonLocation getStartLocation(Object srcRef) {
-        // We don't keep track of offsets at this level (only reader does)
-        long totalChars = -1L;
+    public final void valueStarted() {
+        ++_index;
+    }
 
-        return new JsonLocation(srcRef, totalChars, _lineNr, _columnNr);
+    public void setCurrentName(String name) {
+        _currentName = name;
     }
 
     public void setNamesToWrap(Set<String> namesToWrap) {

src/test/java/com/fasterxml/jackson/dataformat/xml/lists/ListDeser393Test.java

@@ -2,8 +2,6 @@
 
 import java.util.*;
 
-import com.fasterxml.jackson.annotation.JsonInclude;
-
 import com.fasterxml.jackson.databind.ObjectMapper;
 
 import com.fasterxml.jackson.dataformat.xml.XmlTestBase;
@@ -12,20 +10,6 @@
 
 public class ListDeser393Test extends XmlTestBase
 {
-    @JacksonXmlRootElement(localName = "result")
-    @JsonInclude(JsonInclude.Include.NON_NULL)
-    static class Value393 {
-        private Prices393 prices = new Prices393();
-
-        public void setPrices(Prices393 prices) {
-            this.prices = prices;
-        }
-
-        public Prices393 getPrices() {
-            return this.prices;
-        }
-    }
-
     @JacksonXmlRootElement(localName = "prices")
     static class Prices393 {
         private List<Price393> price = new ArrayList<Price393>();