test(rglob): add regression tests for issue p-ranav#3

.. and invalid rglob matching when using a pattern like `foo/**` on
a non-existing directory

Author: jochil

test/rglob_test.cpp

@@ -1,14 +1,50 @@
+#include <filesystem>
+#include <fstream>
 #include <gtest/gtest.h>
-
+#include <stdlib.h>
 
 #ifdef USE_SINGLE_HEADER
 #include "glob/glob.hpp"
 #else
 #include "glob/glob.h"
 #endif
 
+namespace fs = std::filesystem;
+
+fs::path mkdir_temp() {
+  std::srand(std::time(nullptr));
+  fs::path temp_dir = fs::temp_directory_path() / ("rglob_test_" + std::to_string(std::rand()));
 
+  fs::create_directories(temp_dir);
+  return temp_dir;
+}
+
+// regression test to avoid matching an non existing file
 TEST(rglobTest, MatchNonExistent) {
-    auto matches = glob::rglob("non-existent/**");
-    EXPECT_EQ(matches.size(), 0);
+  auto matches = glob::rglob("non-existent/**");
+  EXPECT_EQ(matches.size(), 0);
+}
+
+// see https://github.com/p-ranav/glob/issues/3
+TEST(rglobTest, Issue3) {
+  auto temp_dir = mkdir_temp();
+  std::cout << "Temporary directory: " << temp_dir << std::endl;
+
+  fs::path sub1 = temp_dir / "sub";
+  fs::path sub2 = sub1 / "sub";
+  EXPECT_TRUE(fs::create_directory(sub1));
+  EXPECT_TRUE(fs::create_directory(sub2));
+
+  std::ofstream(temp_dir / "file.txt").close();
+  std::ofstream(sub1 / "file.txt").close();
+  std::ofstream(sub2 / "file.txt").close();
+
+  auto pattern = temp_dir.string() + "/**/*.txt";
+  std::cout << "Pattern: " << pattern << std::endl;
+
+  auto matches = glob::rglob(pattern);
+  EXPECT_EQ(matches.size(), 3);
+  EXPECT_EQ(matches[0].string(), (temp_dir / "file.txt").string());
+  EXPECT_EQ(matches[1].string(), (sub1 / "file.txt").string());
+  EXPECT_EQ(matches[2].string(), (sub2 / "file.txt").string());
 }