Add logging for errors while sending embeds

Not that it’s worth much because the discord API is a useless piece of
trash when it comes to error messages. Like, seriously. Might as well
throw no error at all.
Received a 400 response from Discord with body {"embed": ["fields"]}!
Thanks for nothing. Fix in next commit.

src/main/kotlin/moe/kageru/kagebot/MessageUtil.kt

@@ -1,5 +1,6 @@
 package moe.kageru.kagebot
 
+import moe.kageru.kagebot.Util.failed
 import moe.kageru.kagebot.config.Config
 import org.javacord.api.entity.message.Message
 import org.javacord.api.entity.message.MessageAuthor
@@ -30,7 +31,10 @@ object MessageUtil {
             setTimestampToNow()
             op()
         }
-        sendMessage(embed)
+        val sent = sendMessage(embed)
+        if (sent.failed()) {
+            // for logging
+        }
     }
 
     /**

src/main/kotlin/moe/kageru/kagebot/Util.kt

@@ -73,6 +73,11 @@ object Util {
         try {
             join()
         } catch (e: CompletionException) {
+            Log.warn("""Error during CompletableFuture:
+                |$e
+                |${e.localizedMessage}
+                |${e.stackTrace.joinToString("\n\t")}
+            """.trimMargin())
             // we don’t care about this error, but I don’t want to spam stdout
         }
         return isCompletedExceptionally

src/main/kotlin/moe/kageru/kagebot/features/WelcomeFeature.kt

@@ -32,8 +32,10 @@ class WelcomeFeature(rawWelcome: RawWelcomeFeature) : MessageFeature, EventFeatu
 
     override fun handle(message: MessageCreateEvent) {
         embed?.let {
-            MessageUtil.sendEmbed(message.channel, it)
-        }
+            val sent = MessageUtil.sendEmbed(message.channel, it)
+            // invoke this for logging
+            sent.failed()
+        } ?: Log.info("Welcome command was triggered, but no welcome embed defined.")
     }
 
     private fun hasFallback(): Boolean = fallbackChannel != null && fallbackMessage != null

src/test/kotlin/moe/kageru/kagebot/TestUtil.kt

@@ -40,9 +40,15 @@ object TestUtil {
         return mockk {
             every { messageContent } returns content
             every { readableMessageContent } returns content
-            every { channel.sendMessage(capture(replies)) } returns mockk()
-            every { channel.sendMessage(capture(replyEmbeds)) } returns mockk()
-            every { channel.sendMessage(capture(files)) } returns mockk()
+            every { channel.sendMessage(capture(replies)) } returns mockk(relaxed = true) {
+                every { isCompletedExceptionally } returns false
+            }
+            every { channel.sendMessage(capture(replyEmbeds)) } returns mockk(relaxed = true) {
+                every { isCompletedExceptionally } returns false
+            }
+            every { channel.sendMessage(capture(files)) } returns mockk(relaxed = true) {
+                every { isCompletedExceptionally } returns false
+            }
             every { message.canYouDelete() } returns true
             every { isPrivateMessage } returns false
             // We can’t use a nested mock here because other fields of messageAuthor might
@@ -59,7 +65,7 @@ object TestUtil {
     fun messageableAuthor(messages: MutableList<EmbedBuilder> = mutableListOf()): User {
         return mockk {
             every { getRoles(any()) } returns emptyList()
-            every { sendMessage(capture(messages)) } returns mockk()
+            every { sendMessage(capture(messages)) } returns mockk(relaxed = true)
         }
     }
 
@@ -71,11 +77,13 @@ object TestUtil {
         val channel = mockk<Optional<ServerTextChannel>>(relaxed = true) {
             every { isPresent } returns true
             every { get() } returns mockk {
-                every { sendMessage(capture(sentEmbeds)) } returns mockk {
-                    every { join() } returns mockk()
+                every { sendMessage(capture(sentEmbeds)) } returns mockk(relaxed = true) {
+                    every { join() } returns mockk {
+                        every { isCompletedExceptionally } returns false
+                    }
                     every { isCompletedExceptionally } returns false
                 }
-                every { sendMessage(capture(sentMessages)) } returns mockk()
+                every { sendMessage(capture(sentMessages)) } returns mockk(relaxed = true)
             }
         }
         val api = mockk<DiscordApi> {
@@ -88,7 +96,9 @@ object TestUtil {
                 every { getMembersByName(any()) } returns listOf(mockk(relaxed = true) {
                     every { id } returns 123
                     every { getRoles(any()) } returns listOf(TEST_ROLE)
-                    every { sendMessage(capture(dmEmbeds)) } returns mockk()
+                    every { sendMessage(capture(dmEmbeds)) } returns mockk(relaxed = true) {
+                        every { isCompletedExceptionally } returns false
+                    }
                 })
             })
         }

src/test/kotlin/moe/kageru/kagebot/features/TimeoutFeatureTest.kt

@@ -12,6 +12,7 @@ import org.javacord.api.entity.message.embed.EmbedBuilder
 class TimeoutFeatureTest : StringSpec({
     TestUtil.prepareTestEnvironment()
     "should remove and store roles" {
+        clearTimeouts()
         TestUtil.mockMessage("!timeout kageru 99999999").process()
         Dao.getAllTimeouts().let {
             it.size shouldBe 1