Add doc as second params to validation message function

lib/error/validator.js

@@ -12,15 +12,16 @@ class ValidatorError extends MongooseError {
    * Schema validator error
    *
    * @param {Object} properties
+   * @param {Document} doc
    * @api private
    */
-  constructor(properties) {
+  constructor(properties, doc) {
     let msg = properties.message;
     if (!msg) {
       msg = MongooseError.messages.general.default;
     }
 
-    const message = formatMessage(msg, properties);
+    const message = formatMessage(msg, properties, doc);
     super(message);
 
     properties = Object.assign({}, properties, { message: message });
@@ -75,9 +76,9 @@ ValidatorError.prototype.formatMessage = formatMessage;
  * @api private
  */
 
-function formatMessage(msg, properties) {
+function formatMessage(msg, properties, doc) {
   if (typeof msg === 'function') {
-    return msg(properties);
+    return msg(properties, doc);
   }
 
   const propertyNames = Object.keys(properties);

lib/schematype.js

@@ -1290,7 +1290,7 @@ SchemaType.prototype.doValidate = function(value, fn, scope, options) {
     validatorProperties.value = value;
 
     if (validator instanceof RegExp) {
-      validate(validator.test(value), validatorProperties);
+      validate(validator.test(value), validatorProperties, scope);
       continue;
     }
 
@@ -1299,7 +1299,7 @@ SchemaType.prototype.doValidate = function(value, fn, scope, options) {
     }
 
     if (value === undefined && validator !== this.requiredValidator) {
-      validate(true, validatorProperties);
+      validate(true, validatorProperties, scope);
       continue;
     }
 
@@ -1319,19 +1319,19 @@ SchemaType.prototype.doValidate = function(value, fn, scope, options) {
 
     if (ok != null && typeof ok.then === 'function') {
       ok.then(
-        function(ok) { validate(ok, validatorProperties); },
+        function(ok) { validate(ok, validatorProperties, scope); },
         function(error) {
           validatorProperties.reason = error;
           validatorProperties.message = error.message;
           ok = false;
-          validate(ok, validatorProperties);
+          validate(ok, validatorProperties, scope);
         });
     } else {
-      validate(ok, validatorProperties);
+      validate(ok, validatorProperties, scope);
     }
   }
 
-  function validate(ok, validatorProperties) {
+  function validate(ok, validatorProperties, scope) {
     if (err) {
       return;
     }
@@ -1343,7 +1343,7 @@ SchemaType.prototype.doValidate = function(value, fn, scope, options) {
       }
     } else {
       const ErrorConstructor = validatorProperties.ErrorConstructor || ValidatorError;
-      err = new ErrorConstructor(validatorProperties);
+      err = new ErrorConstructor(validatorProperties, scope);
       err[validatorErrorSymbol] = true;
       immediate(function() {
         fn(err);

test/schema.validation.test.js

@@ -1330,6 +1330,33 @@ describe('schema', function() {
       });
     });
 
+    it('Allows for doc to be passed as another parameter gh-12564', function(done) {
+      let document = '';
+      const s = mongoose.Schema({
+        n: {
+          type: String,
+          validate: {
+            validator: function(v) {
+              return v != null;
+            },
+            message: function(properties, doc) {
+              document = doc.toString();
+              return 'fail ' + properties.path + ' on doc ' + doc;
+            }
+          }
+        },
+        field: String
+      });
+      const M = mongoose.model('gh-12564', s);
+      const m = new M({ n: null, field: 'Yo' });
+
+      m.validate(function(error) {
+        assert.equal(error.errors['n'].message.includes(document), true);
+        assert.equal('fail n on doc ' + document, error.errors['n'].message);
+        done();
+      });
+    });
+
     it('evaluate message function for required field gh6523', function(done) {
       const s = mongoose.Schema({
         n: {