Merge pull request #7591 from element-hq/bma/iterateOnClientCreation

Iterate on client creation

features/enterprise/api/src/main/kotlin/io/element/android/features/enterprise/api/ClientBuilderEnterpriseHook.kt

@@ -13,6 +13,23 @@ import io.element.android.libraries.matrix.api.core.SessionId
 /**
  * A hook that can be used to customize the [MatrixClientBuilder] for enterprise features.
  */
-fun interface ClientBuilderEnterpriseHook {
+interface ClientBuilderEnterpriseHook {
-    suspend operator fun invoke(clientBuilder: MatrixClientBuilder, sessionId: SessionId): MatrixClientBuilder
+    /**
+     * Customize the [MatrixClientBuilder] for enterprise features.
+     * This method is invoked everytime a new [MatrixClientBuilder] is created.
+     *
+     * @param clientBuilder The [MatrixClientBuilder] to customize.
+     * @return The customized [MatrixClientBuilder].
+     */
+    suspend fun beforeClientCreation(clientBuilder: MatrixClientBuilder): MatrixClientBuilder
+
+    /**
+     * Customize the [MatrixClientBuilder] for enterprise features.
+     * This method is invoked as well as the other method when a new [MatrixClientBuilder] is created to build a client for a specific session.
+     *
+     * @param clientBuilder The [MatrixClientBuilder] to customize.
+     * @param sessionId The [SessionId] for which the [MatrixClientBuilder] is being created.
+     * @return The customized [MatrixClientBuilder].
+     */
+    suspend fun beforeClientCreationWithSession(clientBuilder: MatrixClientBuilder, sessionId: SessionId): MatrixClientBuilder
 }

features/enterprise/impl-foss/src/main/kotlin/io/element/android/features/enterprise/impl/DefaultClientBuilderEnterpriseHook.kt

@@ -18,7 +18,12 @@ import io.element.android.libraries.matrix.api.core.SessionId
  */
 @ContributesBinding(AppScope::class)
 class DefaultClientBuilderEnterpriseHook : ClientBuilderEnterpriseHook {
-    override suspend fun invoke(clientBuilder: MatrixClientBuilder, sessionId: SessionId): MatrixClientBuilder {
+    override suspend fun beforeClientCreation(clientBuilder: MatrixClientBuilder): MatrixClientBuilder {
+        // No modification
+        return clientBuilder
+    }
+
+    override suspend fun beforeClientCreationWithSession(clientBuilder: MatrixClientBuilder, sessionId: SessionId): MatrixClientBuilder {
         // No modification
         return clientBuilder
     }

features/enterprise/test/src/main/kotlin/io/element/android/features/enterprise/test/FakeClientBuilderEnterpriseHook.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2026 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.enterprise.test
+
+import io.element.android.features.enterprise.api.ClientBuilderEnterpriseHook
+import io.element.android.libraries.matrix.api.MatrixClientBuilder
+import io.element.android.libraries.matrix.api.core.SessionId
+
+class FakeClientBuilderEnterpriseHook(
+    private val beforeClientCreationResult: (MatrixClientBuilder) -> MatrixClientBuilder = { it },
+    private val beforeClientCreationWithSessionResult: (MatrixClientBuilder, SessionId) -> MatrixClientBuilder = { clientBuilder, _ -> clientBuilder },
+) : ClientBuilderEnterpriseHook {
+    override suspend fun beforeClientCreation(clientBuilder: MatrixClientBuilder): MatrixClientBuilder {
+        return beforeClientCreationResult(clientBuilder)
+    }
+
+    override suspend fun beforeClientCreationWithSession(clientBuilder: MatrixClientBuilder, sessionId: SessionId): MatrixClientBuilder {
+        return beforeClientCreationWithSessionResult(clientBuilder, sessionId)
+    }
+}

libraries/matrix/impl/src/main/kotlin/io/element/android/libraries/matrix/impl/RustMatrixClientFactory.kt

@@ -35,7 +35,6 @@ import io.element.android.services.analytics.api.AnalyticsService
 import io.element.android.services.toolbox.api.systemclock.SystemClock
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.withContext
-import org.matrix.rustcomponents.sdk.Client
 import org.matrix.rustcomponents.sdk.ClientBuilder
 import org.matrix.rustcomponents.sdk.CrossProcessLockConfig
 import org.matrix.rustcomponents.sdk.RequestConfig
@@ -100,7 +99,12 @@ class RustMatrixClientFactory(
         )
             .homeserverUrl(sessionData.homeserverUrl)
             .enableAutomaticBackPagination(featureFlagService.isFeatureEnabled(FeatureFlags.AutomaticBackPagination))
-            .let { (clientBuilderEnterpriseHook(RustMatrixClientBuilder(it), SessionId(sessionData.userId)) as RustMatrixClientBuilder).inner }
+            .let {
+                (clientBuilderEnterpriseHook.beforeClientCreationWithSession(
+                    clientBuilder = RustMatrixClientBuilder(it),
+                    sessionId = SessionId(sessionData.userId),
+                ) as RustMatrixClientBuilder).inner
+            }
             .use { it.build() }
 
         client.setMediaRetentionPolicy(
@@ -118,14 +122,6 @@ class RustMatrixClientFactory(
 
         client.restoreSession(sessionData.toSession())
 
-        create(client, sessionData, isMessageSearchAvailable)
-    }
-
-    suspend fun create(
-        client: Client,
-        sessionData: SessionData,
-        isMessageSearchAvailable: Boolean,
-    ): RustMatrixClient {
         val (anonymizedAccessToken, anonymizedRefreshToken) = client.session().anonymizedTokens()
 
         client.setUtdDelegate(UtdTracker(analyticsService))
@@ -135,7 +131,7 @@ class RustMatrixClientFactory(
             .withOfflineMode()
             .finish()
 
-        return RustMatrixClient(
+        RustMatrixClient(
             sessionPaths = sessionData.getSessionPaths(),
             innerClient = client,
             sessionStore = sessionStore,
@@ -227,6 +223,9 @@ class RustMatrixClientFactory(
                 // Workaround for non-nullable proxy parameter in the SDK, since each call to the ClientBuilder returns a new reference we need to keep
                 proxyProvider.provides()?.let { proxy(it) } ?: this
             }
+            .let {
+                (clientBuilderEnterpriseHook.beforeClientCreation(RustMatrixClientBuilder(it)) as RustMatrixClientBuilder).inner
+            }
     }
 }
 

libraries/matrix/impl/src/main/kotlin/io/element/android/libraries/matrix/impl/auth/RustMatrixAuthenticationService.kt

@@ -44,6 +44,7 @@ import io.element.android.libraries.matrix.impl.keys.SecretGenerator
 import io.element.android.libraries.matrix.impl.mapper.toSessionData
 import io.element.android.libraries.matrix.impl.paths.SessionPathsFactory
 import io.element.android.libraries.sessionstorage.api.LoginType
+import io.element.android.libraries.sessionstorage.api.SessionData
 import io.element.android.libraries.sessionstorage.api.SessionStore
 import kotlinx.coroutines.CancellationException
 import kotlinx.coroutines.flow.first
@@ -101,17 +102,7 @@ class RustMatrixAuthenticationService(
         runCatchingExceptions {
             val sessionData = sessionStore.getSession(sessionId.value)
             if (sessionData != null) {
-                if (sessionData.isTokenValid) {
+                restoreSession(sessionData)
-                    // Use the sessionData.passphrase, which can be null for a previously created session
-                    if (sessionData.passphrase == null) {
-                        Timber.w("Restoring a session without a passphrase")
-                    } else {
-                        Timber.w("Restoring a session with a passphrase")
-                    }
-                    rustMatrixClientFactory.create(sessionData)
-                } else {
-                    throw SessionRestorationException.InvalidToken()
-                }
             } else {
                 throw SessionRestorationException.MissingSession(sessionId)
             }
@@ -120,6 +111,19 @@ class RustMatrixAuthenticationService(
         }
     }
 
+    private suspend fun restoreSession(sessionData: SessionData): MatrixClient {
+        if (!sessionData.isTokenValid) {
+            throw SessionRestorationException.InvalidToken()
+        }
+        // Use the sessionData.passphrase, which can be null for a previously created session
+        if (sessionData.passphrase == null) {
+            Timber.w("Restoring a session without a passphrase")
+        } else {
+            Timber.w("Restoring a session with a passphrase")
+        }
+        return rustMatrixClientFactory.create(sessionData)
+    }
+
     private fun getDatabaseKey(): ClientSecret {
         Timber.d("New sessions will be encrypted with a raw key")
         return secretGenerator.generateKey()
@@ -137,7 +141,7 @@ class RustMatrixAuthenticationService(
 
                 client.homeserverLoginDetails().map()
             }.onFailure {
-                clear(destroyClient = true)
+                clear()
             }.mapFailure { failure ->
                 Timber.e(failure, "Failed to set homeserver to $homeserver")
                 failure.mapAuthenticationException()
@@ -165,18 +169,7 @@ class RustMatrixAuthenticationService(
                         passphrase = pendingKey.formattedAsString(),
                         sessionPaths = currentSessionPaths,
                     )
-                val matrixClient = rustMatrixClientFactory.create(client, sessionData, isMessageSearchAvailable())
+                finalizeClientCreation(sessionData)
-
-                // Apply enterprise hooks to the newly created client as soon as possible
-                clientEnterpriseHook(matrixClient)
-
-                newMatrixClientObservers.forEach { it.invoke(matrixClient) }
-                sessionStore.addSession(sessionData)
-
-                // Clean up the strong reference held here since it's no longer necessary
-                clear(destroyClient = false)
-
-                SessionId(sessionData.userId)
             }.mapFailure { failure ->
                 Timber.e(failure, "Failed to login")
                 failure.mapAuthenticationException()
@@ -305,20 +298,7 @@ class RustMatrixAuthenticationService(
                     passphrase = pendingKey.formattedAsString(),
                     sessionPaths = currentSessionPaths,
                 )
-                val matrixClient = rustMatrixClientFactory.create(client, sessionData, isMessageSearchAvailable())
+                finalizeClientCreation(sessionData)
-
-                // Apply enterprise hooks to the newly created client as soon as possible
-                clientEnterpriseHook(matrixClient)
-
-                matrixClient.waitForKnownVerificationState()
-
-                newMatrixClientObservers.forEach { it.invoke(matrixClient) }
-                sessionStore.addSession(sessionData)
-
-                // Clean up the strong reference held here since it's no longer necessary
-                clear(destroyClient = false)
-
-                SessionId(sessionData.userId)
             }.mapFailure { failure ->
                 Timber.e(failure, "Failed to login with OAuth")
                 failure.mapAuthenticationException()
@@ -357,6 +337,7 @@ class RustMatrixAuthenticationService(
                     sessionPaths = emptySessionPaths,
                     qrCodeData = sdkQrCodeLoginData,
                 )
+                currentClient = client
                 client.newLoginWithQrCodeHandler(
                     oauthConfiguration = oAuthConfiguration,
                 ).use {
@@ -374,18 +355,7 @@ class RustMatrixAuthenticationService(
                         passphrase = pendingKey.formattedAsString(),
                         sessionPaths = emptySessionPaths,
                     )
-                val matrixClient = rustMatrixClientFactory.create(client, sessionData, isMessageSearchAvailable())
+                finalizeClientCreation(sessionData)
-
-                // Apply enterprise hooks to the newly created client as soon as possible
-                clientEnterpriseHook(matrixClient)
-
-                newMatrixClientObservers.forEach { it.invoke(matrixClient) }
-                sessionStore.addSession(sessionData)
-
-                // Clean up the strong reference held here since it's no longer necessary
-                clear(destroyClient = false)
-
-                SessionId(sessionData.userId)
             }.mapFailure {
                 when (it) {
                     is QrCodeDecodeException -> QrErrorMapper.map(it)
@@ -393,6 +363,8 @@ class RustMatrixAuthenticationService(
                     else -> it
                 }
             }.onFailure { throwable ->
+                // A QR code login always builds its own client, so it can be disposed of on failure.
+                clear()
                 if (throwable is CancellationException) {
                     throw throwable
                 }
@@ -400,6 +372,27 @@ class RustMatrixAuthenticationService(
             }
         }
 
+    private suspend fun finalizeClientCreation(sessionData: SessionData): SessionId {
+        // Close the client which was used to perform the login before creating the final client.
+        // Both use the same session paths, so their SQLite stores must never be opened at the same time.
+        clear()
+
+        val matrixClient = restoreSession(sessionData)
+        // Apply enterprise hooks to the newly created client as soon as possible
+        clientEnterpriseHook(matrixClient)
+
+        matrixClient.waitForKnownVerificationState()
+
+        newMatrixClientObservers.forEach { it.invoke(matrixClient) }
+        sessionStore.addSession(sessionData)
+
+        // The session paths now hold the data of the account which has just been logged in, so forget
+        // them: they must not be deleted by the rotateSessionPath() of the next login attempt.
+        sessionPaths = null
+
+        return SessionId(sessionData.userId)
+    }
+
     private suspend fun makeClient(
         sessionPaths: SessionPaths,
         config: suspend ClientBuilder.() -> ClientBuilder,
@@ -449,10 +442,8 @@ class RustMatrixAuthenticationService(
             .build()
     }
 
-    private fun clear(destroyClient: Boolean) {
+    private fun clear() {
-        if (destroyClient) {
+        currentClient?.close()
-            currentClient?.close()
-        }
         currentClient = null
     }
 

libraries/matrix/impl/src/test/kotlin/io/element/android/libraries/matrix/impl/RustMatrixClientFactoryTest.kt

@@ -9,11 +9,13 @@
 package io.element.android.libraries.matrix.impl
 
 import com.google.common.truth.Truth.assertThat
+import io.element.android.features.enterprise.test.FakeClientBuilderEnterpriseHook
 import io.element.android.libraries.featureflag.test.FakeFeatureFlagService
 import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.matrix.impl.auth.FakeProxyProvider
 import io.element.android.libraries.matrix.impl.room.FakeTimelineEventFilterFactory
 import io.element.android.libraries.matrix.impl.storage.FakeSqliteStoreBuilderProvider
+import io.element.android.libraries.matrix.impl.storage.SqliteStoreBuilderProvider
 import io.element.android.libraries.network.useragent.SimpleUserAgentProvider
 import io.element.android.libraries.sessionstorage.api.SessionStore
 import io.element.android.libraries.sessionstorage.test.InMemorySessionStore
@@ -51,6 +53,7 @@ fun TestScope.createRustMatrixClientFactory(
     ),
     clientBuilderProvider: ClientBuilderProvider = FakeClientBuilderProvider(),
     workManagerScheduler: FakeWorkManagerScheduler = FakeWorkManagerScheduler(),
+    sqliteStoreBuilderProvider: SqliteStoreBuilderProvider = FakeSqliteStoreBuilderProvider(),
 ) = RustMatrixClientFactory(
     cacheDirectory = cacheDirectory,
     appCoroutineScope = backgroundScope,
@@ -63,7 +66,7 @@ fun TestScope.createRustMatrixClientFactory(
     featureFlagService = FakeFeatureFlagService(),
     timelineEventFilterFactory = FakeTimelineEventFilterFactory(),
     clientBuilderProvider = clientBuilderProvider,
-    sqliteStoreBuilderProvider = FakeSqliteStoreBuilderProvider(),
+    sqliteStoreBuilderProvider = sqliteStoreBuilderProvider,
     workManagerScheduler = workManagerScheduler,
-    clientBuilderEnterpriseHook = { builder, _ -> builder },
+    clientBuilderEnterpriseHook = FakeClientBuilderEnterpriseHook(),
 )

libraries/matrix/impl/src/test/kotlin/io/element/android/libraries/matrix/impl/RustTemporaryMatrixClientFactoryTest.kt

@@ -8,6 +8,7 @@
 package io.element.android.libraries.matrix.impl
 
 import com.google.common.truth.Truth.assertThat
+import io.element.android.features.enterprise.test.FakeClientBuilderEnterpriseHook
 import io.element.android.libraries.featureflag.test.FakeFeatureFlagService
 import io.element.android.libraries.matrix.impl.auth.FakeProxyProvider
 import io.element.android.libraries.matrix.impl.paths.SessionPathsFactory
@@ -77,6 +78,6 @@ class RustTemporaryMatrixClientFactoryTest {
         clientBuilderProvider = clientBuilderProvider,
         sqliteStoreBuilderProvider = FakeSqliteStoreBuilderProvider(),
         workManagerScheduler = workManagerScheduler,
-        clientBuilderEnterpriseHook = { builder, _ -> builder },
+        clientBuilderEnterpriseHook = FakeClientBuilderEnterpriseHook(),
     )
 }

libraries/matrix/impl/src/test/kotlin/io/element/android/libraries/matrix/impl/auth/RustMatrixAuthenticationServiceTest.kt

@@ -12,25 +12,44 @@ import com.google.common.truth.Truth.assertThat
 import io.element.android.features.enterprise.api.EnterpriseService
 import io.element.android.features.enterprise.test.FakeEnterpriseService
 import io.element.android.libraries.featureflag.test.FakeFeatureFlagService
+import io.element.android.libraries.matrix.api.paths.SessionPaths
 import io.element.android.libraries.matrix.impl.ClientBuilderProvider
 import io.element.android.libraries.matrix.impl.FakeClientBuilderProvider
+import io.element.android.libraries.matrix.impl.auth.qrlogin.SdkQrCodeLoginData
 import io.element.android.libraries.matrix.impl.createRustMatrixClientFactory
 import io.element.android.libraries.matrix.impl.fixtures.fakes.FakeFfiClient
 import io.element.android.libraries.matrix.impl.fixtures.fakes.FakeFfiClientBuilder
 import io.element.android.libraries.matrix.impl.fixtures.fakes.FakeFfiHomeserverLoginDetails
+import io.element.android.libraries.matrix.impl.fixtures.fakes.FakeFfiLoginWithQrCodeHandler
+import io.element.android.libraries.matrix.impl.fixtures.fakes.FakeFfiQrCodeData
 import io.element.android.libraries.matrix.impl.paths.SessionPathsFactory
+import io.element.android.libraries.matrix.impl.storage.FakeSqliteStoreBuilder
+import io.element.android.libraries.matrix.impl.storage.FakeSqliteStoreBuilderProvider
+import io.element.android.libraries.matrix.impl.storage.SqliteStoreBuilder
+import io.element.android.libraries.matrix.impl.storage.SqliteStoreBuilderProvider
+import io.element.android.libraries.matrix.test.A_HOMESERVER_URL
+import io.element.android.libraries.matrix.test.A_USER_ID
 import io.element.android.libraries.matrix.test.auth.FakeOAuthRedirectUrlProvider
 import io.element.android.libraries.matrix.test.core.aBuildMeta
 import io.element.android.libraries.sessionstorage.api.SessionStore
 import io.element.android.libraries.sessionstorage.test.InMemorySessionStore
+import io.element.android.libraries.workmanager.test.FakeWorkManagerScheduler
 import io.element.android.tests.testutils.lambda.lambdaRecorder
 import io.element.android.tests.testutils.testCoroutineDispatchers
 import kotlinx.coroutines.test.TestScope
 import kotlinx.coroutines.test.runTest
+import org.junit.Rule
 import org.junit.Test
+import org.junit.rules.TemporaryFolder
+import org.matrix.rustcomponents.sdk.Client
+import org.matrix.rustcomponents.sdk.ClientBuilder
+import org.matrix.rustcomponents.sdk.HumanQrLoginException
 import java.io.File
 
 class RustMatrixAuthenticationServiceTest {
+    @get:Rule
+    val temporaryFolder = TemporaryFolder()
+
     @Test
     fun `setHomeserver is successful`() = runTest {
         val sut = createRustMatrixAuthenticationService(
@@ -74,20 +93,183 @@ class RustMatrixAuthenticationServiceTest {
         closeResult.assertions().isCalledOnce()
     }
 
+    @Test
+    fun `login closes the client used to log in before building the client of the session`() = runTest {
+        val events = mutableListOf<String>()
+        val sut = createRustMatrixAuthenticationService(
+            clientBuilderProvider = FakeSequentialClientBuilderProvider(
+                {
+                    events.add("build login client")
+                    FakeFfiClient(
+                        homeserverLoginDetailsResult = { FakeFfiHomeserverLoginDetails() },
+                        loginResult = { _, _ -> },
+                        closeResult = { events.add("close login client") },
+                    )
+                },
+                {
+                    events.add("build session client")
+                    FakeFfiClient(withUtdHook = {})
+                },
+            ),
+        )
+
+        assertThat(sut.setHomeserver("matrix.org").isSuccess).isTrue()
+        assertThat(sut.login("alice", "password").getOrNull()).isEqualTo(A_USER_ID)
+
+        // The two clients share the same session paths, so the login one must be closed first.
+        assertThat(events).containsExactly("build login client", "close login client", "build session client").inOrder()
+    }
+
+    @Test
+    fun `loginWithQrCode closes the client used to log in before building the client of the session`() = runTest {
+        val events = mutableListOf<String>()
+        val sut = createRustMatrixAuthenticationService(
+            clientBuilderProvider = FakeSequentialClientBuilderProvider(
+                {
+                    events.add("build login client")
+                    FakeFfiClient(
+                        newLoginWithQrCodeHandlerResult = { FakeFfiLoginWithQrCodeHandler() },
+                        closeResult = { events.add("close login client") },
+                    )
+                },
+                {
+                    events.add("build session client")
+                    FakeFfiClient(withUtdHook = {})
+                },
+            ),
+        )
+
+        val result = sut.loginWithQrCode(aSdkQrCodeLoginData()) {}
+
+        assertThat(result.getOrNull()).isEqualTo(A_USER_ID)
+        assertThat(events).containsExactly("build login client", "close login client", "build session client").inOrder()
+    }
+
+    @Test
+    fun `loginWithQrCode closes the client it created when the login fails`() = runTest {
+        val closeResult = lambdaRecorder<Unit> {}
+        val sut = createRustMatrixAuthenticationService(
+            clientBuilderProvider = FakeClientBuilderProvider(
+                provideResult = {
+                    FakeFfiClientBuilder(
+                        buildResult = {
+                            FakeFfiClient(
+                                newLoginWithQrCodeHandlerResult = {
+                                    FakeFfiLoginWithQrCodeHandler(
+                                        scanResult = { throw HumanQrLoginException.Unknown() },
+                                    )
+                                },
+                                closeResult = closeResult,
+                            )
+                        },
+                    )
+                },
+            ),
+        )
+
+        assertThat(sut.loginWithQrCode(aSdkQrCodeLoginData()) {}.isFailure).isTrue()
+        closeResult.assertions().isCalledOnce()
+    }
+
+    private fun aSdkQrCodeLoginData() = SdkQrCodeLoginData(
+        FakeFfiQrCodeData(
+            baseUrlResult = { A_HOMESERVER_URL },
+        )
+    )
+
+    /**
+     * A [ClientBuilderProvider] handing out one [Client] per call, in order.
+     */
+    private class FakeSequentialClientBuilderProvider(
+        private vararg val clients: () -> Client,
+    ) : ClientBuilderProvider {
+        private var index = 0
+        override fun provide(): ClientBuilder = FakeFfiClientBuilder(buildResult = clients[index++])
+    }
+
+    @Test
+    fun `a new login does not delete the session data of the account which has just been logged in`() = runTest {
+        val storeBuilderProvider = SessionDirectoryCreatingSqliteStoreBuilderProvider()
+        val sut = createRustMatrixAuthenticationService(
+            clientBuilderProvider = FakeSequentialClientBuilderProvider(
+                { aLoginFakeFfiClient() },
+                { FakeFfiClient(withUtdHook = {}) },
+                { aLoginFakeFfiClient() },
+            ),
+            sessionPathsFactory = SessionPathsFactory(temporaryFolder.newFolder("base"), temporaryFolder.newFolder("cache")),
+            sqliteStoreBuilderProvider = storeBuilderProvider,
+        )
+
+        assertThat(sut.setHomeserver("matrix.org").isSuccess).isTrue()
+        assertThat(sut.login("alice", "password").getOrNull()).isEqualTo(A_USER_ID)
+        val loggedInSessionPaths = storeBuilderProvider.providedSessionPaths.first()
+
+        // Adding another account rotates the session paths, which must not touch the previous account.
+        assertThat(sut.setHomeserver("matrix.org").isSuccess).isTrue()
+
+        assertThat(loggedInSessionPaths.fileDirectory.exists()).isTrue()
+        assertThat(loggedInSessionPaths.cacheDirectory.exists()).isTrue()
+    }
+
+    @Test
+    fun `a new login deletes the session data of a previous failed login attempt`() = runTest {
+        val storeBuilderProvider = SessionDirectoryCreatingSqliteStoreBuilderProvider()
+        val sut = createRustMatrixAuthenticationService(
+            clientBuilderProvider = FakeSequentialClientBuilderProvider(
+                { aLoginFakeFfiClient() },
+                { throw IllegalStateException("Failed to build the client of the session") },
+                { aLoginFakeFfiClient() },
+            ),
+            sessionPathsFactory = SessionPathsFactory(temporaryFolder.newFolder("base"), temporaryFolder.newFolder("cache")),
+            sqliteStoreBuilderProvider = storeBuilderProvider,
+        )
+
+        assertThat(sut.setHomeserver("matrix.org").isSuccess).isTrue()
+        assertThat(sut.login("alice", "password").isFailure).isTrue()
+        val abandonedSessionPaths = storeBuilderProvider.providedSessionPaths.first()
+
+        assertThat(sut.setHomeserver("matrix.org").isSuccess).isTrue()
+
+        assertThat(abandonedSessionPaths.fileDirectory.exists()).isFalse()
+        assertThat(abandonedSessionPaths.cacheDirectory.exists()).isFalse()
+    }
+
+    private fun aLoginFakeFfiClient() = FakeFfiClient(
+        homeserverLoginDetailsResult = { FakeFfiHomeserverLoginDetails() },
+        loginResult = { _, _ -> },
+    )
+
+    /**
+     * A [SqliteStoreBuilderProvider] which creates the session directories, like the SDK does when it
+     * opens its stores, and records them so that a test can assert on their lifecycle.
+     */
+    private class SessionDirectoryCreatingSqliteStoreBuilderProvider : SqliteStoreBuilderProvider {
+        val providedSessionPaths = mutableListOf<SessionPaths>()
+
+        override fun provide(sessionPaths: SessionPaths): SqliteStoreBuilder {
+            sessionPaths.fileDirectory.mkdirs()
+            sessionPaths.cacheDirectory.mkdirs()
+            providedSessionPaths.add(sessionPaths)
+            return FakeSqliteStoreBuilder()
+        }
+    }
+
     private fun TestScope.createRustMatrixAuthenticationService(
-        sessionStore: SessionStore = InMemorySessionStore(),
+        sessionStore: SessionStore = InMemorySessionStore(updateUserProfileResult = { _, _, _ -> }),
         clientBuilderProvider: ClientBuilderProvider = FakeClientBuilderProvider(),
         enterpriseService: EnterpriseService = FakeEnterpriseService(),
+        sessionPathsFactory: SessionPathsFactory = SessionPathsFactory(File("/base"), File("/cache")),
+        sqliteStoreBuilderProvider: SqliteStoreBuilderProvider = FakeSqliteStoreBuilderProvider(),
     ): RustMatrixAuthenticationService {
-        val baseDirectory = File("/base")
-        val cacheDirectory = File("/cache")
         val rustMatrixClientFactory = createRustMatrixClientFactory(
-            cacheDirectory = cacheDirectory,
+            cacheDirectory = File("/cache"),
             sessionStore = sessionStore,
             clientBuilderProvider = clientBuilderProvider,
+            workManagerScheduler = FakeWorkManagerScheduler(submitLambda = {}),
+            sqliteStoreBuilderProvider = sqliteStoreBuilderProvider,
         )
         return RustMatrixAuthenticationService(
-            sessionPathsFactory = SessionPathsFactory(baseDirectory, cacheDirectory),
+            sessionPathsFactory = sessionPathsFactory,
             coroutineDispatchers = testCoroutineDispatchers(),
             sessionStore = sessionStore,
             rustMatrixClientFactory = rustMatrixClientFactory,

libraries/matrix/impl/src/test/kotlin/io/element/android/libraries/matrix/impl/fixtures/fakes/FakeFfiClient.kt

@@ -25,10 +25,12 @@ import org.matrix.rustcomponents.sdk.Encryption
 import org.matrix.rustcomponents.sdk.HomeserverCapabilities
 import org.matrix.rustcomponents.sdk.HomeserverLoginDetails
 import org.matrix.rustcomponents.sdk.IgnoredUsersListener
+import org.matrix.rustcomponents.sdk.LoginWithQrCodeHandler
 import org.matrix.rustcomponents.sdk.NoHandle
 import org.matrix.rustcomponents.sdk.NotificationClient
 import org.matrix.rustcomponents.sdk.NotificationProcessSetup
 import org.matrix.rustcomponents.sdk.NotificationSettings
+import org.matrix.rustcomponents.sdk.OAuthConfiguration
 import org.matrix.rustcomponents.sdk.ProfileListener
 import org.matrix.rustcomponents.sdk.PusherIdentifiers
 import org.matrix.rustcomponents.sdk.PusherKind
@@ -57,6 +59,8 @@ class FakeFfiClient(
     private val withUtdHook: (UnableToDecryptDelegate) -> Unit = { lambdaError() },
     private val getProfileResult: (String) -> UserProfile = { aRustUserProfile() },
     private val homeserverLoginDetailsResult: () -> HomeserverLoginDetails = { lambdaError() },
+    private val loginResult: (String, String) -> Unit = { _, _ -> lambdaError() },
+    private val newLoginWithQrCodeHandlerResult: () -> LoginWithQrCodeHandler = { lambdaError() },
     private val getStoreSizesResult: () -> StoreSizes = { lambdaError() },
     private val createRoomResult: (CreateRoomParameters) -> String = { lambdaError() },
     private val homeserverCapabilities: HomeserverCapabilities = FakeFfiHomeserverCapabilities(),
@@ -122,6 +126,14 @@ class FakeFfiClient(
         return homeserverLoginDetailsResult()
     }
 
+    override suspend fun login(username: String, password: String, initialDeviceName: String?, deviceId: String?) {
+        loginResult(username, password)
+    }
+
+    override fun newLoginWithQrCodeHandler(oauthConfiguration: OAuthConfiguration): LoginWithQrCodeHandler {
+        return newLoginWithQrCodeHandlerResult()
+    }
+
     override suspend fun setMediaRetentionPolicy(policy: MediaRetentionPolicy) {}
 
     override suspend fun getStoreSizes(): StoreSizes {

libraries/matrix/impl/src/test/kotlin/io/element/android/libraries/matrix/impl/fixtures/fakes/FakeFfiLoginWithQrCodeHandler.kt

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2026 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.matrix.impl.fixtures.fakes
+
+import org.matrix.rustcomponents.sdk.GeneratedQrLoginProgressListener
+import org.matrix.rustcomponents.sdk.LoginWithQrCodeHandler
+import org.matrix.rustcomponents.sdk.NoHandle
+import org.matrix.rustcomponents.sdk.QrCodeData
+import org.matrix.rustcomponents.sdk.QrLoginProgress
+import org.matrix.rustcomponents.sdk.QrLoginProgressListener
+
+class FakeFfiLoginWithQrCodeHandler(
+    private val generateResult: suspend () -> Unit = {},
+    private val scanResult: suspend (QrCodeData) -> Unit = {},
+) : LoginWithQrCodeHandler(NoHandle) {
+    private var scanProgressListener: QrLoginProgressListener? = null
+
+    override suspend fun generate(progressListener: GeneratedQrLoginProgressListener) {
+        generateResult()
+    }
+
+    override suspend fun scan(qrCodeData: QrCodeData, progressListener: QrLoginProgressListener) {
+        scanProgressListener = progressListener
+        scanResult(qrCodeData)
+    }
+
+    fun emitScanProgress(progress: QrLoginProgress) {
+        scanProgressListener?.onUpdate(progress)
+    }
+
+    override fun close() = Unit
+}

libraries/matrix/impl/src/test/kotlin/io/element/android/libraries/matrix/impl/fixtures/fakes/FakeFfiQrCodeData.kt

@@ -14,12 +14,17 @@ import org.matrix.rustcomponents.sdk.QrCodeData
 
 class FakeFfiQrCodeData(
     private val serverNameResult: () -> String? = { lambdaError() },
+    private val baseUrlResult: () -> String? = { lambdaError() },
     private val toBytesResult: () -> ByteArray = { lambdaError() },
 ) : QrCodeData(NoHandle) {
     override fun serverName(): String? {
         return serverNameResult()
     }
 
+    override fun baseUrl(): String? {
+        return baseUrlResult()
+    }
+
     override fun toBytes(): ByteArray {
         return toBytesResult()
     }

tests/konsist/src/test/kotlin/io/element/android/tests/konsist/KonsistClassNameTest.kt

@@ -105,6 +105,7 @@ class KonsistClassNameTest {
                 "FakeListenableFuture",
                 "FakeMediaStoreContentProvider",
                 "FakeParentNode",
+                "FakeSequentialClientBuilderProvider",
             )
             .assertTrue {
                 val interfaceName = it.name