For #15931: Sort Downloads from newest to oldest (#15939)

app/src/main/java/org/mozilla/fenix/library/downloads/DownloadFragment.kt

@@ -8,8 +8,10 @@ import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
+import androidx.annotation.VisibleForTesting
 import kotlinx.android.synthetic.main.fragment_downloads.view.*
 import kotlinx.coroutines.ExperimentalCoroutinesApi
+import mozilla.components.browser.state.state.BrowserState
 import mozilla.components.browser.state.state.content.DownloadState
 import mozilla.components.feature.downloads.AbstractFetchDownloadService
 import mozilla.components.lib.state.ext.consumeFrom
@@ -37,18 +39,7 @@ class DownloadFragment : LibraryPageFragment<DownloadItem>(), UserInteractionHan
     ): View? {
         val view = inflater.inflate(R.layout.fragment_downloads, container, false)
 
-        val items = requireComponents.core.store.state.downloads.map {
-            DownloadItem(
-                it.value.id.toString(),
-                it.value.fileName,
-                it.value.filePath,
-                it.value.contentLength.toString(),
-                it.value.contentType,
-                it.value.status
-            )
-        }.filter {
-            it.status == DownloadState.Status.COMPLETED
-        }.filterNotExistsOnDisk()
+        val items = provideDownloads(requireComponents.core.store.state)
 
         downloadStore = StoreProvider.get(this) {
             DownloadFragmentStore(
@@ -71,6 +62,24 @@ class DownloadFragment : LibraryPageFragment<DownloadItem>(), UserInteractionHan
         return view
     }
 
+    @VisibleForTesting
+    internal fun provideDownloads(state: BrowserState): List<DownloadItem> {
+        return state.downloads.values
+            .sortedByDescending { it.createdTime } // sort from newest to oldest
+            .map {
+                DownloadItem(
+                    it.id,
+                    it.fileName,
+                    it.filePath,
+                    it.contentLength.toString(),
+                    it.contentType,
+                    it.status
+                )
+            }.filter {
+                it.status == DownloadState.Status.COMPLETED
+            }.filterNotExistsOnDisk()
+    }
+
     override val selectedItems get() = downloadStore.state.mode.selectedItems
 
     override fun onCreate(savedInstanceState: Bundle?) {

app/src/test/java/org/mozilla/fenix/library/downloads/DownloadFragmentTest.kt

@@ -0,0 +1,107 @@
+/* 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.library.downloads
+
+import android.os.Environment
+import io.mockk.every
+import io.mockk.mockk
+import mozilla.components.browser.state.state.BrowserState
+import mozilla.components.browser.state.state.content.DownloadState
+import org.junit.Assert.assertEquals
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mozilla.fenix.helpers.FenixRobolectricTestRunner
+import java.io.File
+
+@Suppress("DEPRECATION")
+@RunWith(FenixRobolectricTestRunner::class)
+class DownloadFragmentTest {
+
+    @Test
+    fun `downloads are sorted from newest to oldest`() {
+
+        val downloadedFile1 = File(
+            Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS),
+            "1.pdf"
+        )
+
+        val downloadedFile2 = File(
+            Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS),
+            "2.pdf"
+        )
+
+        val downloadedFile3 = File(
+            Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS),
+            "3.pdf"
+        )
+
+        downloadedFile1.createNewFile()
+        downloadedFile2.createNewFile()
+        downloadedFile3.createNewFile()
+
+        val fragment = DownloadFragment()
+
+        val expectedList = listOf(
+            DownloadItem(
+                "3",
+                "3.pdf",
+                downloadedFile3.path,
+                "null",
+                null,
+                DownloadState.Status.COMPLETED
+            ),
+            DownloadItem(
+                "2",
+                "2.pdf",
+                downloadedFile2.path,
+                "null",
+                null,
+                DownloadState.Status.COMPLETED
+            ),
+            DownloadItem(
+                "1",
+                "1.pdf",
+                downloadedFile1.path,
+                "null",
+                null,
+                DownloadState.Status.COMPLETED
+            )
+        )
+
+        val state: BrowserState = mockk(relaxed = true)
+
+        every { state.downloads } returns mapOf(
+            "1" to DownloadState(
+                id = "1",
+                createdTime = 1,
+                url = "url",
+                fileName = "1.pdf",
+                status = DownloadState.Status.COMPLETED
+            ),
+            "2" to DownloadState(
+                id = "2",
+                createdTime = 2,
+                url = "url",
+                fileName = "2.pdf",
+                status = DownloadState.Status.COMPLETED
+            ),
+            "3" to DownloadState(
+                id = "3",
+                createdTime = 3,
+                url = "url",
+                fileName = "3.pdf",
+                status = DownloadState.Status.COMPLETED
+            )
+        )
+
+        val list = fragment.provideDownloads(state)
+
+        assertEquals(expectedList, list)
+
+        downloadedFile1.delete()
+        downloadedFile2.delete()
+        downloadedFile3.delete()
+    }
+}