For #4776: Added Unit tests for About Page.

import android.view.LayoutInflater

import android.view.ViewGroup

import androidx.annotation.VisibleForTesting

import androidx.recyclerview.widget.RecyclerView

import org.mozilla.fenix.settings.about.viewholders.AboutItemViewHolder

class AboutPageAdapter(private val listener: AboutPageListener) : RecyclerView.Adapter<AboutItemViewHolder>() {

    private var aboutList: List<AboutPageItem>? = null

    @VisibleForTesting

    var aboutList: List<AboutPageItem>? = null

    fun updateData(items: List<AboutPageItem>) {

        this.aboutList = items

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

package org.mozilla.fenix.settings.about

import android.view.ViewGroup

import android.widget.TextView

import assertk.assertThat

import assertk.assertions.isEqualTo

import io.mockk.Runs

import io.mockk.every

import io.mockk.just

import io.mockk.mockk

import io.mockk.spyk

import io.mockk.verify

import kotlinx.android.synthetic.main.about_list_item.view.*

import mozilla.components.support.test.robolectric.testContext

import org.junit.Test

import org.junit.runner.RunWith

import org.mozilla.fenix.TestApplication

import org.mozilla.fenix.settings.about.viewholders.AboutItemViewHolder

import org.robolectric.RobolectricTestRunner

import org.robolectric.annotation.Config

@RunWith(RobolectricTestRunner::class)

@Config(application = TestApplication::class)

class AboutPageAdapterTest {

    private var aboutList: List<AboutPageItem> =

        mutableListOf(

            AboutPageItem.Item(

                AboutItem.ExternalLink(

                    AboutItemType.WHATS_NEW,

                    "https://mozilla.org"

                ), "Libraries"

            ),

            AboutPageItem.Item(AboutItem.Libraries, "Libraries")

        )

    private val listener: AboutPageListener = mockk(relaxed = true)

    @Test

    fun `updateData should set the new data and call notifyDataSetChanged()`() {

        val adapter = spyk(AboutPageAdapter(listener), recordPrivateCalls = true)

        every { adapter.notifyDataSetChanged() } just Runs

        adapter.updateData(aboutList)

        // Wasn't able to test in verify block the 'adapter.aboutList' setter from the updateData method

        assertThat(adapter.aboutList).isEqualTo(aboutList)

        verify {

            adapter.notifyDataSetChanged()

        }

    }

    @Test

    fun `getItemCount on a default instantiated Adapter should return 0`() {

        val adapter = AboutPageAdapter(listener)

        assertThat(adapter.itemCount).isEqualTo(0)

    }

    @Test

    fun `getItemCount after updateData() call should return the correct list size`() {

        val adapter = AboutPageAdapter(listener)

        adapter.updateData(aboutList)

        assertThat(adapter.itemCount).isEqualTo(2)

    }

    @Test

    fun `the adapter uses AboutItemViewHolder`() {

        val adapter = AboutPageAdapter(listener)

        val parentView: ViewGroup = mockk(relaxed = true)

        every { parentView.context } returns testContext

        val viewHolder = adapter.onCreateViewHolder(parentView, AboutItemViewHolder.LAYOUT_ID)

        assertThat(viewHolder::class).isEqualTo(AboutItemViewHolder::class)

    }

    @Test

    fun `the adapter binds the right item to a ViewHolder`() {

        val adapter = AboutPageAdapter(listener)

        val parentView: ViewGroup = mockk(relaxed = true)

        every { parentView.about_item_title } returns TextView(testContext)

        val viewHolder = spyk(AboutItemViewHolder(parentView, mockk()))

        every {

            adapter.onCreateViewHolder(

                parentView,

                AboutItemViewHolder.LAYOUT_ID

            )

        } returns viewHolder

        every { viewHolder.bind(any()) } just Runs

        adapter.updateData(aboutList)

        adapter.bindViewHolder(viewHolder, 1)

        verify { viewHolder.bind(adapter.aboutList?.get(1) as AboutPageItem.Item) }

    }

}