From bedb7085b17575ebd75b78321c8554bafe5b58fe Mon Sep 17 00:00:00 2001
From: Matthew Chen <matthew@signal.org>
Date: Tue, 15 Sep 2020 17:43:15 -0300
Subject: [PATCH] Skip unnecessary queries in attachment finder.

---
 .../Storage/Database/Records/AttachmentFinder.swift  | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/SignalServiceKit/src/Storage/Database/Records/AttachmentFinder.swift b/SignalServiceKit/src/Storage/Database/Records/AttachmentFinder.swift
index 999c253e80..33940f8f8b 100644
--- a/SignalServiceKit/src/Storage/Database/Records/AttachmentFinder.swift
+++ b/SignalServiceKit/src/Storage/Database/Records/AttachmentFinder.swift
@@ -54,6 +54,9 @@ public class AttachmentFinder: NSObject, AttachmentFinderAdapter {
         withAttachmentIds attachmentIds: [String],
         transaction: GRDBReadTransaction
     ) -> [TSAttachment] {
+        guard !attachmentIds.isEmpty else {
+            return []
+        }
         return GRDBAttachmentFinderAdapter.attachments(
             withAttachmentIds: attachmentIds,
             transaction: transaction
@@ -66,6 +69,9 @@ public class AttachmentFinder: NSObject, AttachmentFinderAdapter {
         matchingContentType: String,
         transaction: GRDBReadTransaction
     ) -> [TSAttachment] {
+        guard !attachmentIds.isEmpty else {
+            return []
+        }
         return GRDBAttachmentFinderAdapter.attachments(
             withAttachmentIds: attachmentIds,
             matchingContentType: matchingContentType,
@@ -79,6 +85,9 @@ public class AttachmentFinder: NSObject, AttachmentFinderAdapter {
         ignoringContentType: String,
         transaction: GRDBReadTransaction
     ) -> [TSAttachment] {
+        guard !attachmentIds.isEmpty else {
+            return []
+        }
         return GRDBAttachmentFinderAdapter.attachments(
             withAttachmentIds: attachmentIds,
             ignoringContentType: ignoringContentType,
@@ -92,6 +101,9 @@ public class AttachmentFinder: NSObject, AttachmentFinderAdapter {
         ignoringContentType: String,
         transaction: GRDBReadTransaction
     ) -> Bool {
+        guard !attachmentIds.isEmpty else {
+            return false
+        }
         return GRDBAttachmentFinderAdapter.existsAttachments(
             withAttachmentIds: attachmentIds,
             ignoringContentType: ignoringContentType,