handle internal refs properly

Author: Steve Hanson

bin/unittestschema/idandref.json

@@ -0,0 +1,69 @@
+{
+  "id": "http://example.com/root.json",
+  "definitions": {
+    "A": {
+      "id": "#foo",
+      "type": "integer"
+    },
+    "B": {
+      "id": "other.json",
+      "definitions": {
+        "X": {
+          "id": "#bar",
+          "type": "boolean"
+        },
+        "Y": {
+          "$ref": "#/definitions/X"
+        },
+        "W": {
+          "$ref": "#/definitions/Y"
+        },
+        "Z": {
+          "$ref": "#bar"
+        },
+        "N": {
+          "properties": {
+            "NX": {
+              "$ref": "#/definitions/X"
+            }
+          }
+        }
+      }
+    }
+  },
+  "properties": {
+    "PA1": {
+      "$ref": "http://example.com/root.json#/definitions/A"
+    },
+    "PA2": {
+      "$ref": "#/definitions/A"
+    },
+    "PA3": {
+      "$ref": "#foo"
+    },
+    "PX1": {
+      "$ref": "#/definitions/B/definitions/X"
+    },
+    "PX2Y": {
+      "$ref": "#/definitions/B/definitions/Y"
+    },
+    "PX3Z": {
+      "$ref": "#/definitions/B/definitions/Z"
+    },
+    "PX4": {
+      "$ref": "http://example.com/other.json#/definitions/X"
+    },
+    "PX5": {
+      "$ref": "other.json#/definitions/X"
+    },
+    "PX6": {
+      "$ref": "other.json#bar"
+    },
+    "PX7W": {
+      "$ref": "#/definitions/B/definitions/W"
+    },
+    "PX8N": {
+      "$ref": "#/definitions/B/definitions/N"
+    }
+  }
+}

include/rapidjson/pointer.h

@@ -16,6 +16,7 @@
 #define RAPIDJSON_POINTER_H_
 
 #include "document.h"
+#include "uri.h"
 #include "internal/itoa.h"
 
 #ifdef __clang__
@@ -80,6 +81,8 @@ class GenericPointer {
 public:
     typedef typename ValueType::EncodingType EncodingType;  //!< Encoding type from Value
     typedef typename ValueType::Ch Ch;                      //!< Character type from Value
+    typedef GenericUri<ValueType, Allocator> UriType;
+
 
     //! A token is the basic units of internal representation.
     /*!
@@ -520,6 +523,69 @@ class GenericPointer {
 
     //@}
 
+    //!@name Compute URI
+    //@{
+
+    //! Compute the in-scope URI for a subtree.
+    //  For use with JSON pointers into JSON schema documents.
+    /*!
+        \param root Root value of a DOM sub-tree to be resolved. It can be any value other than document root.
+        \param unresolvedTokenIndex If the pointer cannot resolve a token in the pointer, this parameter can obtain the index of unresolved token.
+        \return Uri if it can be resolved. Otherwise null.
+
+        \note
+        There are only 3 situations when a URI cannot be resolved:
+        1. A value in the path is not an array nor object.
+        2. An object value does not contain the token.
+        3. A token is out of range of an array value.
+
+        Use unresolvedTokenIndex to retrieve the token index.
+    */
+    UriType GetUri(ValueType& root, const UriType& rootUri, size_t* unresolvedTokenIndex = 0) const {
+        static const Ch kIdString[] = { 'i', 'd', '\0' };
+        static const ValueType kIdValue(kIdString, 2);
+        UriType base = rootUri;
+        RAPIDJSON_ASSERT(IsValid());
+        ValueType* v = &root;
+        for (const Token *t = tokens_; t != tokens_ + tokenCount_; ++t) {
+            switch (v->GetType()) {
+                case kObjectType:
+                {
+                    // See if we have an id, and if so resolve with the current base
+                    typename ValueType::MemberIterator m = v->FindMember(kIdValue);
+                    if (m != v->MemberEnd() && (m->value).IsString()) {
+                        UriType here = UriType(m->value);
+                        here.Resolve(base);
+                        base = here;
+                    }
+                    m = v->FindMember(GenericValue<EncodingType>(GenericStringRef<Ch>(t->name, t->length)));
+                    if (m == v->MemberEnd())
+                        break;
+                    v = &m->value;
+                }
+                  continue;
+                case kArrayType:
+                    if (t->index == kPointerInvalidIndex || t->index >= v->Size())
+                        break;
+                    v = &((*v)[t->index]);
+                    continue;
+                default:
+                    break;
+            }
+
+            // Error: unresolved token
+            if (unresolvedTokenIndex)
+                *unresolvedTokenIndex = static_cast<size_t>(t - tokens_);
+            return UriType();
+        }
+        return base;
+    }
+
+    UriType GetUri(const ValueType& root, const UriType& rootUri, size_t* unresolvedTokenIndex = 0) const {
+      return GetUri(const_cast<ValueType&>(root), rootUri, unresolvedTokenIndex);
+    }
+
+
     //!@name Query value
     //@{