Shows how to mock TextUtils methods so that it's possible to unit test classes that use them

MockingTextUtilsMethods.kt

import android.text.TextUtils
import io.mockk.every
import io.mockk.mockkStatic
import org.junit.Assert
import org.junit.Test

class TextValidator {
  fun validate(string: String) = !TextUtils.isEmpty(string)
}

class TextValidatorTest {
  @Test
  fun test() {
    mockkStatic(TextUtils::class)
    every { TextUtils.isEmpty(any()) } answers { arg<String>(0).isEmpty() }

    val tv = TextValidator()
    Assert.assertTrue(tv.validate("Fernando"))
  }
}