diff --git a/core/block.js b/core/block.js
index c7faf8525..0f4bf1cb0 100644
--- a/core/block.js
+++ b/core/block.js
@@ -1024,9 +1024,15 @@ Blockly.Block.prototype.setOnChange = function(onchangeFn) {
  * @return {?Blockly.Field} Named field, or null if field does not exist.
  */
 Blockly.Block.prototype.getField = function(name) {
+  if (typeof name !== 'string') {
+    throw TypeError('Blockly.Block.prototype.getField expects a string ' +
+      'with the field name but received ' +
+      (name === undefined ? 'nothing' : name + ' of type ' + typeof name) +
+      ' instead');
+  }
   for (var i = 0, input; (input = this.inputList[i]); i++) {
     for (var j = 0, field; (field = input.fieldRow[j]); j++) {
-      if (typeof field.name !== "undefined" && field.name == name) {
+      if (field.name === name) {
         return field;
       }
     }
@@ -1124,13 +1130,9 @@ Blockly.Block.prototype.getFieldValue = function(name) {
 /**
  * Sets the value of the given field for this block.
  * @param {*} newValue The value to set.
- * @param {!string} name The name of the field to set the value of.
+ * @param {string} name The name of the field to set the value of.
  */
 Blockly.Block.prototype.setFieldValue = function(newValue, name) {
-  if (typeof name === "undefined") {
-    throw Error("Call to Blockly.Block.prototype.setFieldValue without " +
-        "required second argument of field name.");
-  }
   var field = this.getField(name);
   if (!field) {
     throw Error('Field "' + name + '" not found.');
diff --git a/tests/mocha/block_test.js b/tests/mocha/block_test.js
index e9a2b9fbf..4d310cac2 100644
--- a/tests/mocha/block_test.js
+++ b/tests/mocha/block_test.js
@@ -1112,22 +1112,52 @@ suite('Blocks', function() {
     });
 
     test('Getting Field', function() {
-      chai.assert.instanceOf(this.block.getField("TEXT"), Blockly.Field);
+      chai.assert.instanceOf(this.block.getField('TEXT'), Blockly.Field);
     });
     test('Getting Field without Name', function() {
-      chai.assert.isNull(this.block.getField());
+      chai.assert.throws(this.block.getField.bind(this.block), TypeError);
     });
     test('Getting Value of Field without Name', function() {
-      chai.assert.isNull(this.block.getFieldValue());
+      chai.assert.throws(this.block.getFieldValue.bind(this.block), TypeError);
+    });
+    test('Getting Field with Wrong Type', function() {
+      var testFunction = function() {
+        return 'TEXT';
+      };
+      var inputs = [1, null, testFunction, {toString: testFunction}, ['TEXT']];
+      for (var i = 0; i < inputs.length; i++) {
+        chai.assert.throws(this.block.getField.bind(this.block, inputs[i]),
+            TypeError);
+      }
+    });
+    test('Getting Value of Field with Wrong Type', function() {
+      var testFunction = function() {
+        return 'TEXT';
+      };
+      var inputs = [1, null, testFunction, {toString: testFunction}, ['TEXT']];
+      for (var i = 0; i < inputs.length; i++) {
+        chai.assert.throws(
+            this.block.getFieldValue.bind(this.block, inputs[i]), TypeError);
+      }
     });
     test('Getting/Setting Field Value', function() {
-      chai.assert.equal(this.block.getFieldValue("TEXT"), "test");
-      this.block.setFieldValue("abc", "TEXT");
-      chai.assert.equal(this.block.getFieldValue("TEXT"), "abc");
+      chai.assert.equal(this.block.getFieldValue('TEXT'), 'test');
+      this.block.setFieldValue('abc', 'TEXT');
+      chai.assert.equal(this.block.getFieldValue('TEXT'), 'abc');
     });
     test('Setting Field without Name', function() {
       chai.assert.throws(this.block.setFieldValue.bind(this.block, 'test'));
     });
+    test('Setting Field with Wrong Type', function() {
+      var testFunction = function() {
+        return 'TEXT';
+      };
+      var inputs = [1, null, testFunction, {toString: testFunction}, ['TEXT']];
+      for (var i = 0; i < inputs.length; i++) {
+        chai.assert.throws(this.block.setFieldValue.bind(this.block, 'test',
+            inputs[i]), TypeError);
+      }
+    });
   });
   suite('Icon Management', function() {
     suite('Bubbles and Collapsing', function() {