diff --git a/tests/unistd_test.cpp b/tests/unistd_test.cpp
index ddf0df5..9d809f0 100644
--- a/tests/unistd_test.cpp
+++ b/tests/unistd_test.cpp
@@ -1203,6 +1203,52 @@
   }
 }
 
+class ExecTestHelper {
+ public:
+  char** GetArgs() { return const_cast<char**>(args_.data()); }
+  char** GetEnv() { return const_cast<char**>(env_.data()); }
+
+  void SetArgs(const std::vector<const char*> args) { args_ = args; }
+  void SetEnv(const std::vector<const char*> env) { env_ = env; }
+
+  void Run(const std::function<void ()>& child_fn,
+           int expected_exit_status,
+           const char* expected_output) {
+      int fds[2];
+      ASSERT_NE(pipe2(fds, 0), -1);
+
+      pid_t pid = fork();
+      ASSERT_NE(pid, -1);
+
+      if (pid == 0) {
+          // Child.
+          close(fds[0]);
+          dup2(fds[1], STDOUT_FILENO);
+          dup2(fds[1], STDERR_FILENO);
+          if (fds[1] != STDOUT_FILENO && fds[1] != STDERR_FILENO) close(fds[1]);
+          child_fn();
+          FAIL();
+      }
+
+      // Parent.
+      close(fds[1]);
+      std::string output;
+      char buf[BUFSIZ];
+      ssize_t bytes_read;
+      while ((bytes_read = TEMP_FAILURE_RETRY(read(fds[0], buf, sizeof(buf)))) > 0) {
+          output.append(buf, bytes_read);
+      }
+      close(fds[0]);
+
+      AssertChildExited(pid, expected_exit_status);
+      ASSERT_EQ(expected_output, output);
+  }
+
+ private:
+  std::vector<const char*> args_;
+  std::vector<const char*> env_;
+};
+
 #if defined(__GLIBC__)
 #define BIN_DIR "/bin/"
 #else