From 88120442d23a7e00833e8b0d523a6aa8072287b3 Mon Sep 17 00:00:00 2001
From: Matthew Bauer <mjbauer95@gmail.com>
Date: Fri, 12 Jun 2020 15:32:52 -0500
Subject: [PATCH] Debug when storePath changes

these rewrites should be transparent, but they are important to know
about when debugging
---
 src/libstore/store-api.cc | 4 ++++
 tests/fetchurl.sh         | 7 ++++---
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/src/libstore/store-api.cc b/src/libstore/store-api.cc
index c8dc4744f..7cb48b293 100644
--- a/src/libstore/store-api.cc
+++ b/src/libstore/store-api.cc
@@ -661,6 +661,8 @@ void copyPaths(ref<Store> srcStore, ref<Store> dstStore, const StorePathSet & st
                 FileIngestionMethod ingestionMethod { info->ca.compare(6, 2, "r:") == 0 };
                 Hash hash(std::string(info->ca, ingestionMethod == FileIngestionMethod::Recursive ? 8 : 6));
                 storePathForDst = dstStore->makeFixedOutputPath(ingestionMethod, hash, storePath.name());
+                if (storePathForDst != storePath)
+                    debug("rewriting path '%s' to '%s' for substituter '%s'", srcStore->printStorePath(storePath), dstStore->printStorePath(storePathForDst), dstStore->getUri());
             }
 
             if (dstStore->isValidPath(storePathForDst)) {
@@ -687,6 +689,8 @@ void copyPaths(ref<Store> srcStore, ref<Store> dstStore, const StorePathSet & st
                 FileIngestionMethod ingestionMethod { info->ca.compare(6, 2, "r:") == 0 };
                 Hash hash(std::string(info->ca, ingestionMethod == FileIngestionMethod::Recursive ? 8 : 6));
                 storePathForDst = dstStore->makeFixedOutputPath(ingestionMethod, hash, storePath.name());
+                if (storePathForDst != storePath)
+                    debug("rewriting path '%s' to '%s' for substituter '%s'", srcStore->printStorePath(storePath), dstStore->printStorePath(storePathForDst), dstStore->getUri());
             }
 
             if (!dstStore->isValidPath(storePathForDst)) {
diff --git a/tests/fetchurl.sh b/tests/fetchurl.sh
index 13447d774..510f98843 100644
--- a/tests/fetchurl.sh
+++ b/tests/fetchurl.sh
@@ -35,12 +35,13 @@ clearStore
 other_store=file://$TEST_ROOT/other_store
 
 hash=$(nix hash-file --type sha256 --base16 ./fetchurl.sh)
-storePath=$(nix add-to-store --store $other_store ./fetchurl.sh)
 
-outPath=$(nix-build -vvvvvv '<nix/fetchurl.nix>' --argstr url file:///no-such-dir/fetchurl.sh --argstr sha256 $hash --no-out-link --substituters $other_store)
+storePath=$(nix --store $other_store add-to-store --flat ./fetchurl.sh)
+
+outPath=$(nix-build '<nix/fetchurl.nix>' --argstr url file:///no-such-dir/fetchurl.sh --argstr sha256 $hash --no-out-link --substituters $other_store)
 
 # Test hashed mirrors with an SRI hash.
-nix-build '<nix/fetchurl.nix>' --argstr url file:///no-such-dir/fetchurl.sh --argstr hash $(nix to-sri --type sha512 $hash) \
+nix-build '<nix/fetchurl.nix>' --argstr url file:///no-such-dir/fetchurl.sh --argstr hash $(nix to-sri --type sha256 $hash) \
           --argstr name bla --no-out-link --substituters $other_store
 
 # Test unpacking a NAR.