From 2fa5bac6d847c85d187930b2e49165e8cbe76fd3 Mon Sep 17 00:00:00 2001
From: BoD <BoD@JRAF.org>
Date: Fri, 6 Dec 2024 09:48:38 +0100
Subject: [PATCH] Account for cycles in getReachableCacheKeys

---
 .../cache/normalized/GarbageCollection.kt     |  2 +-
 .../src/commonMain/graphql/operations.graphql |  3 ++
 .../kotlin/ReachableCacheKeysTest.kt          | 34 +++++++++++++------
 3 files changed, 28 insertions(+), 11 deletions(-)

diff --git a/normalized-cache-incubating/src/commonMain/kotlin/com/apollographql/cache/normalized/GarbageCollection.kt b/normalized-cache-incubating/src/commonMain/kotlin/com/apollographql/cache/normalized/GarbageCollection.kt
index 11aa8708..354b9ebf 100644
--- a/normalized-cache-incubating/src/commonMain/kotlin/com/apollographql/cache/normalized/GarbageCollection.kt
+++ b/normalized-cache-incubating/src/commonMain/kotlin/com/apollographql/cache/normalized/GarbageCollection.kt
@@ -21,7 +21,7 @@ fun NormalizedCache.getReachableCacheKeys(): Set<CacheKey> {
     val cacheKeysToCheck = mutableListOf<CacheKey>()
     for ((key, record) in records) {
       reachableCacheKeys.add(CacheKey(key))
-      cacheKeysToCheck.addAll(record.referencedFields())
+      cacheKeysToCheck.addAll(record.referencedFields() - reachableCacheKeys)
     }
     if (cacheKeysToCheck.isNotEmpty()) {
       getReachableCacheKeys(cacheKeysToCheck, reachableCacheKeys)
diff --git a/tests/garbage-collection/src/commonMain/graphql/operations.graphql b/tests/garbage-collection/src/commonMain/graphql/operations.graphql
index 7d22554d..34795e16 100644
--- a/tests/garbage-collection/src/commonMain/graphql/operations.graphql
+++ b/tests/garbage-collection/src/commonMain/graphql/operations.graphql
@@ -37,6 +37,9 @@ query RepositoryListQuery {
 
 fragment RepositoryFragment on Repository {
   id
+  starGazers {
+    id
+  }
 }
 
 query ProjectListQuery {
diff --git a/tests/garbage-collection/src/commonTest/kotlin/ReachableCacheKeysTest.kt b/tests/garbage-collection/src/commonTest/kotlin/ReachableCacheKeysTest.kt
index 1d878fcd..77216fab 100644
--- a/tests/garbage-collection/src/commonTest/kotlin/ReachableCacheKeysTest.kt
+++ b/tests/garbage-collection/src/commonTest/kotlin/ReachableCacheKeysTest.kt
@@ -48,11 +48,18 @@ class ReachableCacheKeysTest {
                     "repositories": [
                       {
                         "__typename": "Repository",
-                        "id": "1"
+                        "id": "1",
+                        "starGazers": [
+                          {
+                            "__typename": "User",
+                            "id": "0"
+                          }
+                        ]
                       },
                       {
                         "__typename": "Repository",
-                        "id": "2"
+                        "id": "2",
+                        "starGazers": []
                       }
                     ]
                   },
@@ -66,11 +73,13 @@ class ReachableCacheKeysTest {
                       "repositories": [
                         {
                           "__typename": "Repository",
-                          "id": "3"
+                          "id": "3",
+                          "starGazers": []
                         },
                         {
                           "__typename": "Repository",
-                          "id": "4"
+                          "id": "4",
+                          "starGazers": []
                         }
                       ]
                     },
@@ -83,15 +92,18 @@ class ReachableCacheKeysTest {
                       "repositories": [
                         {
                           "__typename": "Repository",
-                          "id": "5"
+                          "id": "5",
+                          "starGazers": []
                         },
                         {
                           "__typename": "Repository",
-                          "id": "6"
+                          "id": "6",
+                          "starGazers": []
                         },
                         {
                           "__typename": "Repository",
-                          "id": "7"
+                          "id": "7",
+                          "starGazers": []
                         }
                       ]
                     }
@@ -99,11 +111,13 @@ class ReachableCacheKeysTest {
                   "repositories": [
                     {
                       "__typename": "Repository",
-                      "id": "7"
+                      "id": "7",
+                      "starGazers": []
                     },
                     {
                       "__typename": "Repository",
-                      "id": "8"
+                      "id": "8",
+                      "starGazers": []
                     }
                   ]
                 }
@@ -153,7 +167,7 @@ class ReachableCacheKeysTest {
           store.writeFragment(
               RepositoryFragmentImpl(),
               CacheKey("Repository:500"),
-              RepositoryFragment(id = "500", __typename = "Repository"),
+              RepositoryFragment(id = "500", __typename = "Repository", starGazers = emptyList()),
           )
           reachableCacheKeys = store.accessCache { it.getReachableCacheKeys() }
           assertContentEquals(