Added ComposeScreenNoKeyAvailableFlowTest.testAddEmailToExistingSingl…

…eKeyPassphraseInDatabase().| #597

FlowCrypt/src/androidTest/java/com/flowcrypt/email/ui/ComposeScreenNoKeyAvailableFlowTest.kt

@@ -116,6 +116,42 @@ class ComposeScreenNoKeyAvailableFlowTest : BaseComposeScreenTest() {
       .check(matches(not(hasTextColor(R.color.gray))))
   }
 
+  @Test
+  fun testAddEmailToExistingSingleKeyPassphraseInDatabase() {
+    activeActivityRule?.launch(intent)
+    registerAllIdlingResources()
+    fillInAllFields(
+      to = setOf(
+        requireNotNull(TestConstants.RECIPIENT_WITH_PUBLIC_KEY_ON_ATTESTER.asInternetAddress())
+      )
+    )
+
+    //check that editTextFrom has gray text color. It means a sender doesn't have a private key
+    onView(withId(R.id.editTextFrom))
+      .check(matches(isDisplayed()))
+      .check(matches(hasTextColor(R.color.gray)))
+
+    onView(withId(R.id.menuActionSend))
+      .check(matches(isDisplayed()))
+      .perform(click())
+
+    isDialogWithTextDisplayed(
+      decorView,
+      getResString(R.string.no_key_available, addAccountToDatabaseRule.account.email)
+    )
+
+    onView(withText(R.string.add_email_to_existing_key))
+      .check(matches(isDisplayed()))
+      .perform(click())
+
+    Thread.sleep(2000)
+
+    //check that editTextFrom doesn't have gray text color. It means a sender has a private key.
+    onView(withId(R.id.editTextFrom))
+      .check(matches(isDisplayed()))
+      .check(matches(not(hasTextColor(R.color.gray))))
+  }
+
   companion object {
     @get:ClassRule
     @JvmStatic