From c80565f166a50e55830632d17d4f2559e5cc354f Mon Sep 17 00:00:00 2001
From: Adam Sheldon <adam.sheldon@hotmail.com>
Date: Fri, 6 May 2016 11:54:55 -0700
Subject: [PATCH] Add flag to exclude instance properties from enumeration

---
 lib/Instance.js              |  2 +-
 lib/Property.js              |  7 ++++++-
 test/integration/instance.js | 19 ++++++++++++++++++-
 3 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/lib/Instance.js b/lib/Instance.js
index bfca4dea..030bbd8c 100755
--- a/lib/Instance.js
+++ b/lib/Instance.js
@@ -519,7 +519,7 @@ function Instance(Model, opts) {
 					opts.changes.push(key);
 				}
 			},
-			enumerable: true
+			enumerable: !(prop && !prop.enumerable)
 		});
 	};
 	var addInstanceExtraProperty = function (key) {
diff --git a/lib/Property.js b/lib/Property.js
index fdfc6ba4..c00375ba 100644
--- a/lib/Property.js
+++ b/lib/Property.js
@@ -40,12 +40,17 @@ exports.normalize = function (opts) {
 
 	if (KNOWN_TYPES.indexOf(opts.prop.type) === -1 && !(opts.prop.type in opts.customTypes)) {
 		throw new ORMError("Unknown property type: " + opts.prop.type, 'NO_SUPPORT');
-  }
+	}
 
 	if (!opts.prop.hasOwnProperty("required") && opts.settings.get("properties.required")) {
 		opts.prop.required = true;
 	}
 
+	// Defaults to true. Setting to false hides properties from JSON.stringify(modelInstance).
+	if (!opts.prop.hasOwnProperty("enumerable") || opts.prop.enumerable === true) {
+		opts.prop.enumerable = true;
+	}
+
 	// Defaults to true. Rational means floating point here.
 	if (opts.prop.type == "number" && opts.prop.rational === undefined) {
 		opts.prop.rational = true;
diff --git a/test/integration/instance.js b/test/integration/instance.js
index 1c45382a..882481ca 100644
--- a/test/integration/instance.js
+++ b/test/integration/instance.js
@@ -16,7 +16,8 @@ describe("Model instance", function() {
 				name   : String,
 				age    : { type: 'integer', required: false },
 				height : { type: 'integer', required: false },
-				weight : { type: 'number',  required: false },
+				weight : { type: 'number',  required: false, enumerable: true },
+				secret : { type: 'text',  required: false, enumerable: false },
 				data   : { type: 'object',  required: false }
 			}, {
 				identityCache: false,
@@ -445,5 +446,21 @@ describe("Model instance", function() {
 				});
 			}
 		});
+
+		describe("Enumerable", function () {
+			it("should not stringify properties marked as not enumerable", function (done) {
+				Person.create({ name: 'Dilbert', secret: 'dogbert', weight: 100, data: {data: 3} }, function (err, p) {
+					if (err) return done(err);
+
+					var result = JSON.parse(JSON.stringify(p));
+					should.not.exist(result.secret);
+					should.exist(result.weight);
+					should.exist(result.data);
+					should.exist(result.name);
+
+					done();
+				});
+			});
+		});
 	});
 });