Add test on RustCheckCodeSender

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

@@ -7,7 +7,14 @@
 
 package io.element.android.libraries.matrix.impl.fixtures.fakes
 
+import io.element.android.tests.testutils.lambda.lambdaError
 import org.matrix.rustcomponents.sdk.CheckCodeSender
 import org.matrix.rustcomponents.sdk.NoHandle
 
-class FakeFfiCheckCodeSender : CheckCodeSender(NoHandle)
+class FakeFfiCheckCodeSender(
+    private val sendResult: (UByte) -> Unit = { _ -> lambdaError() }
+) : CheckCodeSender(NoHandle) {
+    override suspend fun send(code: UByte) {
+        sendResult(code)
+    }
+}

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

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2025 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.linknewdevice
+
+import com.google.common.truth.Truth.assertThat
+import io.element.android.libraries.matrix.impl.fixtures.fakes.FakeFfiCheckCodeSender
+import io.element.android.tests.testutils.lambda.lambdaRecorder
+import io.element.android.tests.testutils.lambda.value
+import kotlinx.coroutines.test.StandardTestDispatcher
+import kotlinx.coroutines.test.runTest
+import org.junit.Test
+
+class RustCheckCodeSenderTest {
+    @Test
+    fun `send invokes the Ffi object`() = runTest {
+        val sendResult = lambdaRecorder<UByte, Unit> { }
+        val sut = RustCheckCodeSender(
+            inner = FakeFfiCheckCodeSender(
+                sendResult = sendResult,
+            ),
+            sessionDispatcher = StandardTestDispatcher(testScheduler),
+        )
+        sut.send(1.toUByte())
+        sendResult.assertions().isCalledOnce().with(value(1.toUByte()))
+    }
+
+    @Test
+    fun `validate always returns true for now`() = runTest {
+        val sut = RustCheckCodeSender(
+            inner = FakeFfiCheckCodeSender(),
+            sessionDispatcher = StandardTestDispatcher(testScheduler),
+        )
+        val result = sut.validate(1.toUByte())
+        assertThat(result).isTrue()
+    }
+}