From f5e97a321276182d007a2601698a8803b693c3f7 Mon Sep 17 00:00:00 2001
From: Marcus Holland-Moritz <github@mhxnet.de>
Date: Wed, 29 Nov 2023 17:32:54 +0100
Subject: [PATCH] test: support adding files with random contents

---
 test/test_helpers.cpp | 26 +++++++++++++++++++++++++-
 test/test_helpers.h   |  3 ++-
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/test/test_helpers.cpp b/test/test_helpers.cpp
index 9cd91fb4..3771be47 100644
--- a/test/test_helpers.cpp
+++ b/test/test_helpers.cpp
@@ -24,6 +24,7 @@
 #include <cstring>
 #include <functional>
 #include <iostream>
+#include <random>
 
 #include <fmt/format.h>
 
@@ -258,7 +259,7 @@ void os_access_mock::add_dir(fs::path const& path) {
   add(path, st);
 }
 
-void os_access_mock::add_file(fs::path const& path, size_t size) {
+void os_access_mock::add_file(fs::path const& path, size_t size, bool random) {
   simplestat st;
   std::memset(&st, 0, sizeof(st));
   st.ino = ino_++;
@@ -266,6 +267,29 @@ void os_access_mock::add_file(fs::path const& path, size_t size) {
   st.uid = 1000;
   st.gid = 100;
   st.size = size;
+
+  if (random) {
+    thread_local std::mt19937_64 rng{42};
+
+    std::uniform_int_distribution<> choice_dist{0, 3};
+
+    switch (choice_dist(rng)) {
+    default:
+      break;
+
+    case 0:
+      add(path, st, [size, seed = rng()] {
+        std::mt19937_64 tmprng{seed};
+        std::string rv;
+        rv.resize(size);
+        std::uniform_int_distribution<> byte_dist{0, 255};
+        std::generate(rv.begin(), rv.end(), [&] { return byte_dist(tmprng); });
+        return rv;
+      });
+      return;
+    }
+  }
+
   add(path, st, [size] { return loremipsum(size); });
 }
 
diff --git a/test/test_helpers.h b/test/test_helpers.h
index 5a0a2977..6b89278d 100644
--- a/test/test_helpers.h
+++ b/test/test_helpers.h
@@ -80,7 +80,8 @@ class os_access_mock : public os_access {
            std::function<std::string()> generator);
 
   void add_dir(std::filesystem::path const& path);
-  void add_file(std::filesystem::path const& path, size_t size);
+  void
+  add_file(std::filesystem::path const& path, size_t size, bool random = false);
   void add_file(std::filesystem::path const& path, std::string const& contents);
 
   void set_access_fail(std::filesystem::path const& path);