Replace Mockito Captor by ArgumentMatcher

CaptorToArgumentMatcher.kt

class CaptorToArgumentMatcher {

    @Test
    fun captor() {
        ArgumentCaptor.forClass(JSONObject::class.java).also { captor ->
            verify(tracker).view(eq("screen event"), captor.capture())

            assertThat(captor.value.length()).isEqualTo(3)
            assertThat(captor.value.get("number")).isEqualTo(12.3)
            assertThat(captor.value.get("string")).isEqualTo("value")
            assertThat(captor.value.get("empty")).isEqualTo(null)
        }
    }

    @Test
    fun matcher() {
        verify(tracker).view(eq("screen event"), isJSONObject(mapOf(
                "number" to 12.3,
                "string" to "value",
                "empty" to null
        )))
    }
}

private fun isJSONObject(expected: Map<String, Any?>): JSONObject = argThat {
    val actual: Map<String, Any?> = keys()
            .asSequence()
            .filterIsInstance<String>() // Fix Kotlin compiler error
            .map { it to get(it) }
            .toMap()
     return@argThat actual == expected
}