refactor(libanki): add libanki:testutils

AnkiDroid/build.gradle

@@ -434,6 +434,7 @@ dependencies {
     implementation libs.leakcanary.android
 
     testImplementation project(':testlib')
+    testImplementation project(":libanki:testutils")
 
     // A path for a testing library which provide Parameterized Test
     testImplementation libs.junit.jupiter

AnkiDroid/src/main/java/com/ichi2/anki/CollectionManager.kt

@@ -176,8 +176,7 @@ object CollectionManager {
     }
 
     /**
-     * Close the currently cached backend and discard it. Useful when enabling the V16 scheduler in the
-     * dev preferences, or if the active language changes. Saves and closes the collection if open.
+     * Close the currently cached backend and discard it. Saves and closes the collection if open.
      */
     suspend fun discardBackend() {
         withQueue {

AnkiDroid/src/test/java/com/ichi2/anki/RobolectricTest.kt

@@ -51,6 +51,7 @@ import com.ichi2.anki.observability.undoableOp
 import com.ichi2.anki.preferences.sharedPrefs
 import com.ichi2.compat.customtabs.CustomTabActivityHelper
 import com.ichi2.testutils.AndroidTest
+import com.ichi2.testutils.CollectionManagerTestAdapter
 import com.ichi2.testutils.TaskSchedulerRule
 import com.ichi2.testutils.TestClass
 import com.ichi2.testutils.common.FailOnUnhandledExceptionRule
@@ -59,6 +60,8 @@ import com.ichi2.testutils.filter
 import com.ichi2.utils.InMemorySQLiteOpenHelperFactory
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.runBlocking
+import kotlinx.coroutines.test.TestScope
+import kotlinx.coroutines.test.UnconfinedTestDispatcher
 import kotlinx.coroutines.test.resetMain
 import net.ankiweb.rsdroid.BackendException
 import net.ankiweb.rsdroid.testing.RustBackendLoader
@@ -113,6 +116,9 @@ open class RobolectricTest :
     @get:Rule
     val timeoutRule: TimeoutRule = TimeoutRule.seconds(60)
 
+    override val collectionManager: CollectionManagerTestAdapter
+        get() = CollectionManagerTestAdapter
+
     @Before
     @CallSuper
     open fun setUp() {
@@ -521,6 +527,11 @@ open class RobolectricTest :
             throw e
         }
     }
+
+    override suspend fun TestScope.runTestInner(testBody: suspend TestScope.() -> Unit) {
+        collectionManager.setTestDispatcher(UnconfinedTestDispatcher(testScheduler))
+        testBody()
+    }
 }
 
 private fun getLatestAlertDialog(): AlertDialog =

AnkiDroid/src/test/java/com/ichi2/testutils/CollectionManagerTestAdapter.kt

@@ -0,0 +1,35 @@
+/*
+ *  Copyright (c) 2025 David Allison <davidallisongithub@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify it under
+ *  the terms of the GNU General Public License as published by the Free Software
+ *  Foundation; either version 3 of the License, or (at your option) any later
+ *  version.
+ *
+ *  This program is distributed in the hope that it will be useful, but WITHOUT ANY
+ *  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ *  PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along with
+ *  this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.ichi2.testutils
+
+import com.ichi2.anki.CollectionManager
+import com.ichi2.anki.libanki.testutils.TestCollectionManager
+import kotlinx.coroutines.CoroutineDispatcher
+
+/**
+ * Adapts [CollectionManager] to [TestCollectionManager]
+ */
+object CollectionManagerTestAdapter : TestCollectionManager {
+    override suspend fun discardBackend() {
+        CollectionManager.discardBackend()
+    }
+
+    /** @see CollectionManager.setTestDispatcher */
+    fun setTestDispatcher(dispatcher: CoroutineDispatcher) {
+        CollectionManager.setTestDispatcher(dispatcher)
+    }
+}

AnkiDroid/src/test/java/com/ichi2/testutils/JvmTest.kt

@@ -26,6 +26,8 @@ import com.ichi2.anki.libanki.Storage
 import com.ichi2.anki.observability.ChangeManager
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.runBlocking
+import kotlinx.coroutines.test.TestScope
+import kotlinx.coroutines.test.UnconfinedTestDispatcher
 import kotlinx.coroutines.test.resetMain
 import net.ankiweb.rsdroid.BackendException
 import net.ankiweb.rsdroid.testing.RustBackendLoader
@@ -50,6 +52,9 @@ open class JvmTest : TestClass {
         RustBackendLoader.ensureSetup()
     }
 
+    override val collectionManager: CollectionManagerTestAdapter
+        get() = CollectionManagerTestAdapter
+
     override val col: Collection
         get() {
             if (_col == null) {
@@ -121,4 +126,9 @@ open class JvmTest : TestClass {
     ) {
         Assume.assumeThat(actual, matcher)
     }
+
+    override suspend fun TestScope.runTestInner(testBody: suspend TestScope.() -> Unit) {
+        collectionManager.setTestDispatcher(UnconfinedTestDispatcher(testScheduler))
+        testBody()
+    }
 }

AnkiDroid/src/test/java/com/ichi2/testutils/TestClass.kt

@@ -17,7 +17,6 @@
 package com.ichi2.testutils
 
 import android.annotation.SuppressLint
-import com.ichi2.anki.CollectionManager
 import com.ichi2.anki.ioDispatcher
 import com.ichi2.anki.isCollectionEmpty
 import com.ichi2.anki.libanki.Card
@@ -31,6 +30,7 @@ import com.ichi2.anki.libanki.NotetypeJson
 import com.ichi2.anki.libanki.Notetypes
 import com.ichi2.anki.libanki.QueueType
 import com.ichi2.anki.libanki.exception.ConfirmModSchemaException
+import com.ichi2.anki.libanki.testutils.TestCollectionManager
 import com.ichi2.testutils.ext.addNote
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.test.StandardTestDispatcher
@@ -50,6 +50,8 @@ import kotlin.time.Duration.Companion.milliseconds
 interface TestClass {
     val col: Collection
 
+    val collectionManager: TestCollectionManager
+
     fun addBasicNote(
         front: String = "Front",
         back: String = "Back",
@@ -322,9 +324,13 @@ interface TestClass {
         repeat(times) {
             if (times != 1) Timber.d("------ Executing test $it/$times ------")
             kotlinx.coroutines.test.runTest(context, dispatchTimeoutMs.milliseconds) {
-                CollectionManager.setTestDispatcher(UnconfinedTestDispatcher(testScheduler))
-                testBody()
+                runTestInner(testBody)
             }
         }
     }
+
+    /** Runs [testBody], supporting [TestScope]-specific setup & teardown */
+    suspend fun TestScope.runTestInner(testBody: suspend TestScope.() -> Unit) {
+        testBody()
+    }
 }

libanki/build.gradle.kts

@@ -73,6 +73,8 @@ dependencies {
     testImplementation(libs.junit.jupiter)
     testImplementation(libs.json)
 
+    testImplementation(project(":libanki:testutils"))
+
     // project lint checks
     // PERF: some rules do not need to be applied... but the full run was 3s
     lintChecks(project(":lint-rules"))

libanki/testutils/.gitignore

@@ -0,0 +1 @@
+/build

libanki/testutils/build.gradle.kts

@@ -0,0 +1,69 @@
+/*
+ *  Copyright (c) 2025 David Allison <davidallisongithub@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify it under
+ *  the terms of the GNU General Public License as published by the Free Software
+ *  Foundation; either version 3 of the License, or (at your option) any later
+ *  version.
+ *
+ *  This program is distributed in the hope that it will be useful, but WITHOUT ANY
+ *  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ *  PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along with
+ *  this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import org.jetbrains.kotlin.gradle.dsl.JvmTarget
+import java.util.Properties
+
+plugins {
+    alias(libs.plugins.android.library)
+    alias(libs.plugins.kotlin.android)
+}
+
+android {
+    namespace = "com.ichi2.anki.libanki.testutils"
+    compileSdk =
+        libs.versions.compileSdk
+            .get()
+            .toInt()
+
+    defaultConfig {
+        minSdk =
+            libs.versions.minSdk
+                .get()
+                .toInt()
+    }
+
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_11
+        targetCompatibility = JavaVersion.VERSION_11
+    }
+    kotlin {
+        compilerOptions {
+            jvmTarget = JvmTarget.JVM_11
+        }
+    }
+}
+
+dependencies {
+    implementation(project(":common"))
+    implementation(project(":libanki"))
+
+    val localProperties = Properties()
+    if (project.rootProject.file("local.properties").exists()) {
+        localProperties.load(project.rootProject.file("local.properties").inputStream())
+    }
+    if (localProperties["local_backend"] == "true") {
+        implementation(files("../../Anki-Android-Backend/rsdroid/build/outputs/aar/rsdroid-release.aar"))
+        testImplementation(files("../../Anki-Android-Backend/rsdroid-testing/build/libs/rsdroid-testing.jar"))
+    } else {
+        implementation(libs.ankiBackend.backend)
+        testImplementation(libs.ankiBackend.testing)
+    }
+
+    implementation(libs.jakewharton.timber)
+    implementation(libs.kotlinx.coroutines.core)
+    implementation(libs.kotlinx.coroutines.test)
+}

libanki/testutils/src/main/java/com/ichi2/anki/libanki/testutils/TestCollectionManager.kt

@@ -0,0 +1,28 @@
+/*
+ *  Copyright (c) 2025 David Allison <davidallisongithub@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify it under
+ *  the terms of the GNU General Public License as published by the Free Software
+ *  Foundation; either version 3 of the License, or (at your option) any later
+ *  version.
+ *
+ *  This program is distributed in the hope that it will be useful, but WITHOUT ANY
+ *  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ *  PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along with
+ *  this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.ichi2.anki.libanki.testutils
+
+/**
+ * Trimmed down version of `com.ichi2.anki.CollectionManager` which can be used without a reference
+ * to Android & AnkiDroid app logic
+ */
+interface TestCollectionManager {
+    /**
+     * Close the currently cached backend and discard it. Saves and closes the collection if open.
+     */
+    suspend fun discardBackend()
+}

settings.gradle.kts

@@ -17,4 +17,4 @@ dependencyResolutionManagement {
     }
 }
 
-include(":lint-rules", ":api", ":AnkiDroid", ":testlib", ":common", ":libanki")
+include(":lint-rules", ":api", ":AnkiDroid", ":testlib", ":common", ":libanki", ":libanki:testutils")