Handle and report invalid notify(err) argument. Fixes #110.

notify(err…) now catches and reports the case where err=null|undefined|0|true|false.

An error-level log is printed and Error is constructed and sent to Bugsnag
with the offending parameter. All of the arguments are captured and sent
in the report's metadata too, to help provide context for when this happens.

lib/bugsnag.js

@@ -116,6 +116,13 @@ Bugsnag.notify = function(error, options, cb) {
     if (!options) {
         options = {};
     }
+    if ((!error && typeof error !== "string") || error === true) {
+        Configuration.logger.error("Bugsnag.notify(error…) accepts an object or a string but was called with '" + error + "'");
+        options.metaData = {
+            "notify() arguments": JSON.stringify([].map.call(arguments, function(arg) { return arg }), Utils.sensibleReplacer, 2)
+        };
+        error = new Error("[Bugsnag] Bugsnag.notify(error…) accepts an object or a string but was called with '" + error + "'");
+    }
     if (!Bugsnag.shouldNotify()) {
         if (cb) {
             if (!Configuration.apiKey) {

lib/utils.js

@@ -143,6 +143,16 @@ var Utils = {
 
     _filterHandler: function() {
         return '[FILTERED]';
+    },
+
+    // this custom replacer (for use in JSON.stringify(obj, replacer, spaces)) is implemented to
+    // ensure values such as `undefined` and `Function` get serialized in a sensible way. Otherwise
+    // `Function`s get removed and `undefined` gets converted to null, which would be a misleading
+    // representation of what was passed to this function.
+    sensibleReplacer:  function (key, value) {
+        if (value === undefined) return "undefined";
+        if (typeof value === "function") return value.name ? ("[function " + value.name + "()]") : "[anonymous function]";
+        return value;
     }
 };
 

test/notification.js

@@ -367,4 +367,30 @@ describe("Notification", function() {
             });
         });
     });
+
+    describe("bad input", function() {
+        it("notify(err) should handle bad input", function () {
+          should.not.throw(function () {
+              Bugsnag.notify(null);
+          });
+          should.not.throw(function () {
+              Bugsnag.notify(undefined);
+          });
+          should.not.throw(function () {
+              Bugsnag.notify(0);
+          });
+          should.not.throw(function () {
+              Bugsnag.notify([]);
+          });
+          should.not.throw(function () {
+              Bugsnag.notify(new Date());
+          });
+          should.not.throw(function () {
+              Bugsnag.notify(false);
+          });
+          should.not.throw(function () {
+              Bugsnag.notify(true);
+          });
+        });
+    });
 });

test/utils.js

@@ -349,4 +349,10 @@ describe("utils", function() {
             data.password.should.equal('[FILTERED]')
         });
     });
+
+    describe("sensibleReplacer", function () {
+        JSON.stringify({ a: undefined }, Utils.sensibleReplacer).should.equal("{\"a\":\"undefined\"}");
+        JSON.stringify({ a: function () {} }, Utils.sensibleReplacer).should.equal("{\"a\":\"[function a()]\"}");
+        JSON.stringify({ a: [ function () {} ] }, Utils.sensibleReplacer).should.equal("{\"a\":[\"[anonymous function]\"]}");
+    });
 });