From ef34fd0656e844ccc54fd105cdda9970d7e944b4 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Mon, 4 Oct 2021 13:47:38 +0200
Subject: [PATCH] scanForReferences(): Use a StorePathSet

---
 src/libstore/build/local-derivation-goal.cc |  3 +-
 src/libstore/references.cc                  | 35 ++++++++++-----------
 src/libstore/references.hh                  |  6 ++--
 3 files changed, 20 insertions(+), 24 deletions(-)

diff --git a/src/libstore/build/local-derivation-goal.cc b/src/libstore/build/local-derivation-goal.cc
index b1852a6bb..2ba1b3f59 100644
--- a/src/libstore/build/local-derivation-goal.cc
+++ b/src/libstore/build/local-derivation-goal.cc
@@ -2140,8 +2140,7 @@ void LocalDerivationGoal::registerOutputs()
 
         /* Pass blank Sink as we are not ready to hash data at this stage. */
         NullSink blank;
-        auto references = worker.store.parseStorePathSet(
-            scanForReferences(blank, actualPath, worker.store.printStorePathSet(referenceablePaths)));
+        auto references = scanForReferences(blank, actualPath, referenceablePaths);
 
         outputReferencesIfUnregistered.insert_or_assign(
             outputName,
diff --git a/src/libstore/references.cc b/src/libstore/references.cc
index 3a07c1411..eb70844a2 100644
--- a/src/libstore/references.cc
+++ b/src/libstore/references.cc
@@ -72,43 +72,40 @@ struct RefScanSink : Sink
 };
 
 
-std::pair<PathSet, HashResult> scanForReferences(const string & path,
-    const PathSet & refs)
+std::pair<StorePathSet, HashResult> scanForReferences(
+    const string & path,
+    const StorePathSet & refs)
 {
     HashSink hashSink { htSHA256 };
     auto found = scanForReferences(hashSink, path, refs);
     auto hash = hashSink.finish();
-    return std::pair<PathSet, HashResult>(found, hash);
+    return std::pair<StorePathSet, HashResult>(found, hash);
 }
 
-PathSet scanForReferences(Sink & toTee,
-    const string & path, const PathSet & refs)
+StorePathSet scanForReferences(
+    Sink & toTee,
+    const Path & path,
+    const StorePathSet & refs)
 {
     RefScanSink refsSink;
     TeeSink sink { refsSink, toTee };
-    std::map<string, Path> backMap;
+    std::map<std::string, StorePath> backMap;
 
     for (auto & i : refs) {
-        auto baseName = std::string(baseNameOf(i));
-        string::size_type pos = baseName.find('-');
-        if (pos == string::npos)
-            throw Error("bad reference '%1%'", i);
-        string s = string(baseName, 0, pos);
-        assert(s.size() == refLength);
-        assert(backMap.find(s) == backMap.end());
-        // parseHash(htSHA256, s);
-        refsSink.hashes.insert(s);
-        backMap[s] = i;
+        std::string hashPart(i.hashPart());
+        auto inserted = backMap.emplace(hashPart, i).second;
+        assert(inserted);
+        refsSink.hashes.insert(hashPart);
     }
 
     /* Look for the hashes in the NAR dump of the path. */
     dumpPath(path, sink);
 
     /* Map the hashes found back to their store paths. */
-    PathSet found;
+    StorePathSet found;
     for (auto & i : refsSink.seen) {
-        std::map<string, Path>::iterator j;
-        if ((j = backMap.find(i)) == backMap.end()) abort();
+        auto j = backMap.find(i);
+        assert(j != backMap.end());
         found.insert(j->second);
     }
 
diff --git a/src/libstore/references.hh b/src/libstore/references.hh
index 4f12e6b21..73e674109 100644
--- a/src/libstore/references.hh
+++ b/src/libstore/references.hh
@@ -1,13 +1,13 @@
 #pragma once
 
-#include "types.hh"
 #include "hash.hh"
+#include "path.hh"
 
 namespace nix {
 
-std::pair<PathSet, HashResult> scanForReferences(const Path & path, const PathSet & refs);
+std::pair<StorePathSet, HashResult> scanForReferences(const Path & path, const StorePathSet & refs);
 
-PathSet scanForReferences(Sink & toTee, const Path & path, const PathSet & refs);
+StorePathSet scanForReferences(Sink & toTee, const Path & path, const StorePathSet & refs);
 
 struct RewritingSink : Sink
 {