Provide unified solution for dir name randomization in tests

This approach actually wraps the unique identifier generation into the
function that provides the output path for a test.
This way we don't need to add `CreateRandomUuid()` everywhere that we
have `test::OutputPath` and instead just rename to
`test::OutputPathRandomDir`

Bug: webrtc:15833
Change-Id: Ic9b69b5b599727f07b2906569a84a40edeecd1a0
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/338645
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Jeremy Leconte <jleconte@google.com>
Reviewed-by: Artem Titov <titovartem@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41730}

test/BUILD.gn

@@ -861,6 +861,7 @@ rtc_library("fileutils") {
     ":fileutils_override_api",
     ":fileutils_override_impl",
     "../rtc_base:checks",
+    "../rtc_base:ssl",
     "../rtc_base:stringutils",
   ]
   absl_deps = [

test/testsupport/file_utils.cc

@@ -54,6 +54,7 @@
 
 #include "absl/strings/string_view.h"
 #include "rtc_base/checks.h"
+#include "rtc_base/helpers.h"
 #include "rtc_base/string_utils.h"
 #include "rtc_base/strings/string_builder.h"
 #include "test/testsupport/file_utils_override.h"
@@ -94,6 +95,13 @@ std::string OutputPath() {
   return webrtc::test::internal::OutputPath();
 }
 
+std::string OutputPathWithRandomDirectory() {
+  std::string path = webrtc::test::internal::OutputPath();
+  std::string rand_dir = path + rtc::CreateRandomUuid();
+
+  return CreateDir(rand_dir) ? rand_dir + std::string(kPathDelimiter) : path;
+}
+
 std::string WorkingDir() {
   return webrtc::test::internal::WorkingDir();
 }

test/testsupport/file_utils.h

@@ -42,6 +42,11 @@ ABSL_CONST_INIT extern const absl::string_view kPathDelimiter;
 // found, the current working directory ("./") is returned as a fallback.
 std::string OutputPath();
 
+// Same as the above but appends a randomly named folder at the end of the path
+// Primerly used to provide a solution for stress testing environments to
+// prevent colission of files and folders.
+std::string OutputPathWithRandomDirectory();
+
 // Generates an empty file with a unique name in the specified directory and
 // returns the file name and path.
 // TODO(titovartem) rename to TempFile and next method to TempFilename

test/testsupport/file_utils_unittest.cc

@@ -120,6 +120,28 @@ TEST_F(FileUtilsTest, OutputPathFromRootWorkingDir) {
   ASSERT_THAT(result, EndsWith(expected_end));
 }
 
+TEST_F(FileUtilsTest, RandomOutputPathFromUnchangedWorkingDir) {
+  rtc::SetRandomTestMode(true);
+  std::string fixed_first_uuid = "def01482-f829-429a-bfd4-841706e92cdd";
+  std::string expected_end = ExpectedRootDirByPlatform() + fixed_first_uuid +
+                             std::string(kPathDelimiter);
+  std::string result = webrtc::test::OutputPathWithRandomDirectory();
+
+  ASSERT_THAT(result, EndsWith(expected_end));
+}
+
+TEST_F(FileUtilsTest, RandomOutputPathFromRootWorkingDir) {
+  ASSERT_EQ(0, chdir(kPathDelimiter.data()));
+
+  rtc::SetRandomTestMode(true);
+  std::string fixed_first_uuid = "def01482-f829-429a-bfd4-841706e92cdd";
+  std::string expected_end = ExpectedRootDirByPlatform() + fixed_first_uuid +
+                             std::string(kPathDelimiter);
+  std::string result = webrtc::test::OutputPathWithRandomDirectory();
+
+  ASSERT_THAT(result, EndsWith(expected_end));
+}
+
 TEST_F(FileUtilsTest, TempFilename) {
   std::string temp_filename = webrtc::test::TempFilename(
       webrtc::test::OutputPath(), "TempFilenameTest");