AndroidThreeTen not working in unit test without robolectric?

Question

I'm having trouble creating a unit test without needing robolectric. I am using AndroidThreeTen.init(this) in my code and when I run my test if I disable robolectric I get an error: `org.threeten.bp.zone.ZoneRulesException: No time-zone data files registered` and if I leave it enabled I get this: `[Robolectric] com.mycomp.,yapp.utilities.log.LogTest.on Calling function w it returns an Int: sdk=28; resources=BINARY` I have tried using testImplementation ‘com.jakewharton.threetenabp:threetenabp:1.1.0’ made no difference. I have AndroidThreeTen.init(this) called in my application and testApplication. any ideas? this is my test ``` @Test fun `on Calling function i it returns an Int`() { assertThat("Returned class is not an Int", Log.i("Test", "Test"), isA(Int::class.java)) assertThat("Returned Int is not 0", Log.i("Test", "Test"), `is`(0)) } ``` Or do I have to use robolectric because of this? (Side note: Log is not the util.log from android but my own class) (edited)

Accepted Answer

JVM unit tests don't run on Android runtime. Instead of ThreeTenABP, you can just use ThreeTenBP directly to get the same API initialised for a regular JVM.

In my project build.gradle I use a setup like:

```
implementation "com.jakewharton.threetenabp:threetenabp:${threetenabpVersion}"
testImplementation("org.threeten:threetenbp:${threetenbpVersion}") {
    exclude module: "com.jakewharton.threetenabp:threetenabp:${threetenabpVersion}"
}
```

where

```
threetenabpVersion = '1.2.0'
threetenbpVersion = '1.3.8'
```

This uses ThreeTenBP via ThreeTenABP normally, but in unit test configuration it adds TreeTenBP directly as a dependency, with its init code. Cannot remember exactly why I put in the `exclude` rule; it's been like that for a few years already.

AndroidThreeTen not working in unit test without robolectric?

Solution

Problem