Middle ground, placeholder and counter

Fixes: thunderbird#9056 (+1 squashed commit)
Squashed commits:
[ade7fcb] Adjust fix for testing

Fixes: thunderbird#9056

Author: asoucar

feature/navigation/drawer/dropdown/src/main/kotlin/net/thunderbird/feature/navigation/drawer/dropdown/domain/usecase/GetDisplayTreeFolder.kt

@@ -2,7 +2,6 @@ package net.thunderbird.feature.navigation.drawer.dropdown.domain.usecase
 
 import app.k9mail.core.mail.folder.api.Folder
 import app.k9mail.core.mail.folder.api.FolderType
-import java.util.UUID
 import kotlinx.collections.immutable.persistentListOf
 import kotlinx.collections.immutable.toImmutableList
 import net.thunderbird.feature.navigation.drawer.dropdown.domain.DomainContract.UseCase
@@ -12,6 +11,7 @@ import net.thunderbird.feature.navigation.drawer.dropdown.domain.entity.DisplayT
 import net.thunderbird.feature.navigation.drawer.dropdown.domain.entity.DisplayUnifiedFolder
 
 internal class GetDisplayTreeFolder : UseCase.GetDisplayTreeFolder {
+    private var placeholderCounter = 0L
 
     override fun invoke(folders: List<DisplayFolder>, maxDepth: Int): DisplayTreeFolder {
         val unifiedFolderTreeList = folders.filterIsInstance<DisplayUnifiedFolder>().map {
@@ -88,10 +88,11 @@ internal class GetDisplayTreeFolder : UseCase.GetDisplayTreeFolder {
     }
 
     private fun createPlaceholderFolder(name: String): DisplayAccountFolder {
+        placeholderCounter += 1
         return DisplayAccountFolder(
-            accountId = "accountId",
+            accountId = "placeholder",
             folder = Folder(
-                id = UUID.randomUUID().mostSignificantBits,
+                id = placeholderCounter,
                 name = name,
                 type = FolderType.REGULAR,
                 isLocalOnly = false,

feature/navigation/drawer/dropdown/src/test/kotlin/net/thunderbird/feature/navigation/drawer/dropdown/domain/usecase/GetDisplayTreeFolderTest.kt

@@ -199,9 +199,9 @@ class GetDisplayTreeFolderTest {
                     children = persistentListOf(
                         DisplayTreeFolder(
                             displayFolder = DisplayAccountFolder(
-                                accountId = "accountId",
+                                accountId = "placeholder",
                                 folder = Folder(
-                                    id = 0,
+                                    id = 1L,
                                     name = "(Unnamed)/(Unnamed)",
                                     type = FolderType.REGULAR,
                                     isLocalOnly = false,
@@ -238,8 +238,8 @@ class GetDisplayTreeFolderTest {
                 ),
                 DisplayTreeFolder(
                     displayFolder = DisplayAccountFolder(
-                        accountId = "accountId",
-                        folder = Folder(id = 0, name = "valid1", type = FolderType.REGULAR, isLocalOnly = false),
+                        accountId = "placeholder",
+                        folder = Folder(id = 2, name = "valid1", type = FolderType.REGULAR, isLocalOnly = false),
                         isInTopGroup = true,
                         unreadMessageCount = 0,
                         starredMessageCount = 0,
@@ -250,9 +250,9 @@ class GetDisplayTreeFolderTest {
                     children = persistentListOf(
                         DisplayTreeFolder(
                             displayFolder = DisplayAccountFolder(
-                                accountId = "accountId",
+                                accountId = "placeholder",
                                 folder = Folder(
-                                    id = 0,
+                                    id = 3L,
                                     name = "valid1/(Unnamed)",
                                     type = FolderType.REGULAR,
                                     isLocalOnly = false,
@@ -321,7 +321,8 @@ class GetDisplayTreeFolderTest {
             children = persistentListOf(
                 createDisplayTreeFolder(
                     displayFolder = createDisplayAccountFolder(
-                        folderId = 0L,
+                        accountId = "placeholder",
+                        folderId = 1L,
                         folderName = "folderLevel1",
                         unreadMessageCount = 0,
                         starredMessageCount = 0,
@@ -379,7 +380,8 @@ class GetDisplayTreeFolderTest {
             children = persistentListOf(
                 createDisplayTreeFolder(
                     displayFolder = createDisplayAccountFolder(
-                        folderId = 0,
+                        accountId = "placeholder",
+                        folderId = 1,
                         folderName = "level1",
                         unreadMessageCount = 0,
                         starredMessageCount = 0,
@@ -390,7 +392,8 @@ class GetDisplayTreeFolderTest {
                     children = persistentListOf(
                         createDisplayTreeFolder(
                             displayFolder = createDisplayAccountFolder(
-                                folderId = 0,
+                                accountId = "placeholder",
+                                folderId = 2L,
                                 folderName = "level1/level2",
                                 unreadMessageCount = 0,
                                 starredMessageCount = 0,
@@ -427,9 +430,10 @@ class GetDisplayTreeFolderTest {
             folderName: String,
             unreadMessageCount: Int,
             starredMessageCount: Int,
-        ): DisplayAccountFolder {
+            accountId: String = "accountId",
+            ): DisplayAccountFolder {
             return DisplayAccountFolder(
-                accountId = "accountId",
+                accountId = accountId,
                 folder = Folder(
                     id = folderId,
                     name = folderName,