From 6525265f4640221efb0039ddbd6849a3b04babc9 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Mon, 31 Jul 2023 12:22:06 -0400
Subject: [PATCH] `LocalStore::verifyPath`: Try to clarify data flow with more
 scopes

It was initially unclear to me which of these are temporary state for
the verify paths computation, and which of these are the results of that
computation to be used in the rest of the function. Now, it is clear,
and enforced.
---
 src/libstore/local-store.cc | 29 ++++++++++++++++-------------
 1 file changed, 16 insertions(+), 13 deletions(-)

diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc
index 9049f33aa..17e2ebc38 100644
--- a/src/libstore/local-store.cc
+++ b/src/libstore/local-store.cc
@@ -1499,21 +1499,24 @@ bool LocalStore::verifyStore(bool checkContents, RepairFlag repair)
     auto fdGCLock = openGCLock();
     FdLock gcLock(fdGCLock.get(), ltRead, true, "waiting for the big garbage collector lock...");
 
-    StorePathSet store;
-    for (auto & i : readDirectory(realStoreDir)) {
-        try {
-            store.insert({i.name});
-        } catch (BadStorePath &) { }
-    }
-
-    /* Check whether all valid paths actually exist. */
-    printInfo("checking path existence...");
-
     StorePathSet validPaths;
-    StorePathSet done;
 
-    for (auto & i : queryAllValidPaths())
-        verifyPath(i, store, done, validPaths, repair, errors);
+    {
+        StorePathSet store;
+        for (auto & i : readDirectory(realStoreDir)) {
+            try {
+                store.insert({i.name});
+            } catch (BadStorePath &) { }
+        }
+
+        /* Check whether all valid paths actually exist. */
+        printInfo("checking path existence...");
+
+        StorePathSet done;
+
+        for (auto & i : queryAllValidPaths())
+            verifyPath(i, store, done, validPaths, repair, errors);
+    }
 
     /* Optionally, check the content hashes (slow). */
     if (checkContents) {