From 40c023ecfe49fea6e66db34c5f841fcf7001cbeb Mon Sep 17 00:00:00 2001
From: Julian Stecklina <js@alien8.de>
Date: Sun, 29 Mar 2020 23:47:48 +0200
Subject: [PATCH] fetchGit: don't use std::filesystem to filter git repos

Using std::filesystem means also having to link with -lstdc++fs on
some platforms and it's hard to discover for what platforms this is
needed. As all the functionality is already implemented as utilities,
use those instead.
---
 src/libexpr/local.mk            |  4 ----
 src/libexpr/primops/fetchGit.cc | 17 ++++++++++-------
 2 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/src/libexpr/local.mk b/src/libexpr/local.mk
index b6ee82424..9b5fcc561 100644
--- a/src/libexpr/local.mk
+++ b/src/libexpr/local.mk
@@ -8,11 +8,7 @@ libexpr_SOURCES := $(wildcard $(d)/*.cc) $(wildcard $(d)/primops/*.cc) $(d)/lexe
 
 libexpr_LIBS = libutil libstore libnixrust
 
-ifeq ($(CXX), g++)
-libexpr_LDFLAGS = -lstdc++fs
-else
 libexpr_LDFLAGS =
-endif
 
 ifneq ($(OS), FreeBSD)
  libexpr_LDFLAGS += -ldl
diff --git a/src/libexpr/primops/fetchGit.cc b/src/libexpr/primops/fetchGit.cc
index f138b755c..d60e6b803 100644
--- a/src/libexpr/primops/fetchGit.cc
+++ b/src/libexpr/primops/fetchGit.cc
@@ -6,7 +6,6 @@
 #include "hash.hh"
 #include "tarfile.hh"
 
-#include <filesystem>
 #include <sys/time.h>
 
 #include <regex>
@@ -28,6 +27,13 @@ struct GitInfo
 
 std::regex revRegex("^[0-9a-fA-F]{40}$");
 
+static bool isNotDotGitDirectory(const Path & path)
+{
+  static const std::regex gitDirRegex("^(?:.*/)?\\.git$");
+
+  return not std::regex_match(path, gitDirRegex);
+}
+
 GitInfo exportGit(ref<Store> store, const std::string & uri,
     std::optional<std::string> ref, std::string rev,
     const std::string & name, bool fetchSubmodules)
@@ -175,6 +181,7 @@ GitInfo exportGit(ref<Store> store, const std::string & uri,
 
     Path tmpDir = createTempDir();
     AutoDelete delTmpDir(tmpDir, true);
+    PathFilter filter = defaultPathFilter;
 
     // Submodule support can be improved by adding caching to the submodules themselves. At the moment, only the root
     // repo is cached.
@@ -193,11 +200,7 @@ GitInfo exportGit(ref<Store> store, const std::string & uri,
         runProgram("git", true, { "-C", tmpDir, "remote", "add", "origin", uri });
         runProgram("git", true, { "-C", tmpDir, "submodule", "--quiet", "update", "--init", "--recursive" });
 
-        for (const auto& p : std::filesystem::recursive_directory_iterator(tmpDir)) {
-            if (p.path().filename() == ".git") {
-                std::filesystem::remove_all(p.path());
-            }
-        }
+	filter = isNotDotGitDirectory;
     } else {
         auto source = sinkToSource([&](Sink & sink) {
             RunOptions gitOptions("git", { "-C", cacheDir, "archive", gitInfo.rev });
@@ -208,7 +211,7 @@ GitInfo exportGit(ref<Store> store, const std::string & uri,
         unpackTarfile(*source, tmpDir);
     }
 
-    gitInfo.storePath = store->printStorePath(store->addToStore(name, tmpDir));
+    gitInfo.storePath = store->printStorePath(store->addToStore(name, tmpDir, true, htSHA256, filter));
 
     gitInfo.revCount = std::stoull(runProgram("git", true, { "-C", cacheDir, "rev-list", "--count", gitInfo.rev }));