Tests fail when run on high resolution monitors

What MDC-Web Version are you using?

0.6.0

What browser(s) is this bug affecting?

NA, however it is happening on a 4k monitor

What OS are you using?

16.04.2 LTS

What are the steps to reproduce the bug?

1. Procure a high resolution monitor
2. Pull on master and make no changes
3. Run npm run test
4. Observe the failed test

What is the expected behavior?

Expect the tests to pass

What is the actual behavior?

The console complains with the following:

Chrome 56.0.2924 (Linux 0.0.0) MDCSimpleMenu adapter#getAnchorDimensions returns the dimensions of the anchor container FAILED
	AssertionError: expected 20.99609375 to equal 21
	    at Context.<anonymous> (webpack:///test/unit/mdc-menu/mdc-simple-menu.test.js:311:9 <- test/unit/index.js:16729:16)

Any other information you believe would be useful?

I have not been able to reproduce the issue on any computer that has monitor specs similar to a Macbook Pro’s retina display or lower.

[anton-kachurin]

Was able to reproduce the bug by running Chrome with --force-device-scale-factor flag with a fractional value:

diff --git a/karma.conf.js b/karma.conf.js
index f094b67..6eb0447 100644
--- a/karma.conf.js
+++ b/karma.conf.js
@@ -21,6 +21,10 @@ const USING_TRAVISCI = Boolean(process.env.TRAVIS);
 const USING_SL = Boolean(process.env.SAUCE_USERNAME && process.env.SAUCE_ACCESS_KEY);

 const SL_LAUNCHERS = {
+  'chrome-device-scale': {
+    base: 'Chrome',
+    flags: ['--force-device-scale-factor=1.33'],
+  },
   'sl-chrome-stable': {
     base: 'SauceLabs',
     browserName: 'chrome',
@@ -165,5 +169,5 @@ module.exports = function(config) {
 };

 function determineBrowsers() {
-  return USING_SL ? Object.keys(SL_LAUNCHERS) : ['Chrome'];
+  return USING_SL ? Object.keys(SL_LAUNCHERS) : ['chrome-device-scale'];
 }

Getting exactly the same error:

Chrome 56.0.2924 (Windows 10 0.0.0) MDCSimpleMenu adapter#getAnchorDimensions returns the dimensions of the anchor container FAILED
        AssertionError: expected 20.9938907623291 to equal 21
            at Context.<anonymous> (webpack:///test/unit/mdc-menu/mdc-simple-menu.test.js:311:9 <- test/unit/index.js:15487:16)

@amsheehan, you probably will be able to choose some --force-device-scale-factor value which will prevent the test from failing. Most likely --force-device-scale-factor=1 will solve the problem.

[moog16]

@abhiomkar, you tried to reproduce and weren’t able to. I’m going to close this issue.