diff --git a/CMakeLists.txt b/CMakeLists.txt
index 443a6640b..d7250acd3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -162,6 +162,9 @@ ADD_EXECUTABLE(fish_key_reader
                src/fish_key_reader.cpp src/print_help.cpp)
 FISH_LINK_DEPS(fish_key_reader)
 
+# A helper for running tests.
+ADD_EXECUTABLE(fish_test_helper src/fish_test_helper.cpp)
+
 # Set up tests.
 INCLUDE(cmake/Tests.cmake)
 
diff --git a/cmake/Tests.cmake b/cmake/Tests.cmake
index cab0158e9..7b398744e 100644
--- a/cmake/Tests.cmake
+++ b/cmake/Tests.cmake
@@ -44,14 +44,17 @@ ADD_DEPENDENCIES(test test_low_level tests_dir)
 
 # Make the directory in which to run tests.
 # Also symlink fish to where the tests expect it to be.
+# Lastly put fish_test_helper there too.
 ADD_CUSTOM_TARGET(tests_buildroot_target
                   COMMAND ${CMAKE_COMMAND} -E make_directory ${TEST_INSTALL_DIR}
                   COMMAND DESTDIR=${TEST_INSTALL_DIR} ${CMAKE_COMMAND}
                           --build ${CMAKE_CURRENT_BINARY_DIR} --target install
+                  COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_BINARY_DIR}/fish_test_helper
+                          ${TEST_INSTALL_DIR}/${CMAKE_INSTALL_PREFIX}/bin
                   COMMAND ${CMAKE_COMMAND} -E create_symlink
                           ${TEST_INSTALL_DIR}/${CMAKE_INSTALL_PREFIX}
                           ${TEST_ROOT_DIR}
-                  DEPENDS fish)
+                  DEPENDS fish fish_test_helper)
 
 IF(NOT FISH_IN_TREE_BUILD)
   # We need to symlink share/functions for the tests.
diff --git a/src/fish_test_helper.cpp b/src/fish_test_helper.cpp
new file mode 100644
index 000000000..50f3bca7a
--- /dev/null
+++ b/src/fish_test_helper.cpp
@@ -0,0 +1,32 @@
+// fish_test_helper is a little program with no fish dependencies that acts like certain other
+// programs, allowing fish to test its behavior.
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+static void become_foreground_then_print_stderr() {
+    if (tcsetpgrp(STDOUT_FILENO, getpgrp()) < 0) {
+        perror("tcsetgrp");
+        exit(EXIT_FAILURE);
+    }
+    usleep(1000000 / 4);  //.25 secs
+    fprintf(stderr, "become_foreground_then_print_stderr done\n");
+}
+
+int main(int argc, char *argv[]) {
+    if (argc <= 1) {
+        fprintf(stderr, "No commands given.");
+        return 0;
+    }
+    for (int i = 1; i < argc; i++) {
+        if (!strcmp(argv[i], "become_foreground_then_print_stderr")) {
+            become_foreground_then_print_stderr();
+        } else {
+            fprintf(stderr, "%s: Unknown command: %s\n", argv[0], argv[i]);
+            return EXIT_FAILURE;
+        }
+    }
+    return 0;
+}