From 271908a2c488092ece6d7b1045bf605165b7305e Mon Sep 17 00:00:00 2001
From: Beat Richartz <brichartz@pivotal.io>
Date: Thu, 25 May 2017 10:08:33 +0100
Subject: [PATCH] Fail when one of the arguments passed into toBeCloseTo
 matcher is null

---
 spec/core/matchers/toBeCloseToSpec.js | 16 ++++++++++++++++
 src/core/matchers/toBeCloseTo.js      |  6 ++++++
 2 files changed, 22 insertions(+)

diff --git a/spec/core/matchers/toBeCloseToSpec.js b/spec/core/matchers/toBeCloseToSpec.js
index 8c892958..a0eca07f 100644
--- a/spec/core/matchers/toBeCloseToSpec.js
+++ b/spec/core/matchers/toBeCloseToSpec.js
@@ -29,6 +29,22 @@ describe("toBeCloseTo", function() {
     expect(result.pass).toBe(true);
   });
 
+  it("fails when one of the arguments is null", function() {
+    var matcher = jasmineUnderTest.matchers.toBeCloseTo();
+
+    expect(function() {
+      matcher.compare(null, null);
+    }).toThrowError('Cannot use toBeCloseTo with null. Arguments evaluated to: expect(null).toBeCloseTo(null).');
+
+    expect(function() {
+      matcher.compare(0, null);
+    }).toThrowError('Cannot use toBeCloseTo with null. Arguments evaluated to: expect(0).toBeCloseTo(null).');
+
+    expect(function() {
+      matcher.compare(null, 0);
+    }).toThrowError('Cannot use toBeCloseTo with null. Arguments evaluated to: expect(null).toBeCloseTo(0).');
+  });
+
   it("rounds expected values", function() {
     var matcher = jasmineUnderTest.matchers.toBeCloseTo(),
       result;
diff --git a/src/core/matchers/toBeCloseTo.js b/src/core/matchers/toBeCloseTo.js
index 5f3d7d84..94f7c4ec 100644
--- a/src/core/matchers/toBeCloseTo.js
+++ b/src/core/matchers/toBeCloseTo.js
@@ -15,6 +15,12 @@ getJasmineRequireObj().toBeCloseTo = function() {
           precision = precision || 2;
         }
 
+        if (expected === null || actual === null) {
+          throw new Error('Cannot use toBeCloseTo with null. Arguments evaluated to: ' +
+            'expect(' + actual + ').toBeCloseTo(' + expected + ').'
+          );
+        }
+
         return {
           pass: Math.abs(expected - actual) < (Math.pow(10, -precision) / 2)
         };