diff --git a/tests/checks/disown-parent.fish b/tests/checks/disown-parent.fish
index adfe8e344..9b9a33366 100644
--- a/tests/checks/disown-parent.fish
+++ b/tests/checks/disown-parent.fish
@@ -1,4 +1,5 @@
 # RUN: env fish_test_helper=%fish_test_helper %fish %s
+#REQUIRES: command -v %fish_test_helper
 
 # Ensure that a job which attempts to disown itself does not explode.
 # Here fish_test_helper is the process group leader; we attempt to disown
diff --git a/tests/checks/fds.fish b/tests/checks/fds.fish
index de581e4b2..a86a223f4 100644
--- a/tests/checks/fds.fish
+++ b/tests/checks/fds.fish
@@ -1,4 +1,5 @@
 # RUN: %fish -C "set helper %fish_test_helper" %s
+#REQUIRES: command -v %fish_test_helper
 
 # Check that we don't leave stray FDs.
 
diff --git a/tests/checks/job-control-noninteractive.fish b/tests/checks/job-control-noninteractive.fish
index da4566306..5262ac761 100644
--- a/tests/checks/job-control-noninteractive.fish
+++ b/tests/checks/job-control-noninteractive.fish
@@ -1,4 +1,5 @@
 #RUN: env fth=%fish_test_helper fish=%fish %fish %s
+#REQUIRES: command -v %fish_test_helper
 
 # Ensure job control works in non-interactive environments.
 
diff --git a/tests/checks/pipeline-pgroup.fish b/tests/checks/pipeline-pgroup.fish
index 07da18829..9499ef316 100644
--- a/tests/checks/pipeline-pgroup.fish
+++ b/tests/checks/pipeline-pgroup.fish
@@ -1,4 +1,5 @@
 # RUN: env fth=%fish_test_helper fish=%fish %fish %s
+#REQUIRES: command -v %fish_test_helper
 
 status job-control full
 
diff --git a/tests/checks/sigint.fish b/tests/checks/sigint.fish
index 7838ece07..4bd0d3299 100644
--- a/tests/checks/sigint.fish
+++ b/tests/checks/sigint.fish
@@ -1,4 +1,5 @@
 #RUN: %fish -C "set -g helper %fish_test_helper; set -g fish %fish" %s
+#REQUIRES: command -v %fish_test_helper
 
 # Check that nohup is propagated.
 set output_path (mktemp)
diff --git a/tests/checks/sigint2.fish b/tests/checks/sigint2.fish
index 0160cf3b5..2084d3b97 100644
--- a/tests/checks/sigint2.fish
+++ b/tests/checks/sigint2.fish
@@ -1,6 +1,7 @@
 #RUN: %fish -C "set helper %fish_test_helper" %s
 # This hangs on OpenBSD
 #REQUIRES: test "$(uname)" != OpenBSD
+#REQUIRES: command -v %fish_test_helper
 
 # Command subs run in same pgroup as fish, even if job control is 'all'.
 # Verify that they get the same pgroup across runs (presumably fish's).
diff --git a/tests/checks/signal.fish b/tests/checks/signal.fish
index 20d0fd6c2..b203065e7 100644
--- a/tests/checks/signal.fish
+++ b/tests/checks/signal.fish
@@ -1,4 +1,5 @@
 # RUN: env fish_test_helper=%fish_test_helper %fish -C 'set -l fish %fish' %s
+#REQUIRES: command -v %fish_test_helper
 
 $fish -c 'function main; exit 4; true; end; main'
 echo $status
diff --git a/tests/checks/trap.fish b/tests/checks/trap.fish
index 0b7def74d..c88de3abd 100644
--- a/tests/checks/trap.fish
+++ b/tests/checks/trap.fish
@@ -1,4 +1,5 @@
 # RUN: env fth=%fish_test_helper %fish %s
+#REQUIRES: command -v %fish_test_helper
 
 set -g SIGUSR1_COUNT 0
 
diff --git a/tests/interactive.fish b/tests/interactive.fish
index 268f25435..0a6dca8b1 100755
--- a/tests/interactive.fish
+++ b/tests/interactive.fish
@@ -36,7 +36,8 @@ function test_pexpect_file
         set -lx --prepend PYTHONPATH (realpath $PWD)
         set -lx fish $FISHDIR/fish
         set -lx fish_key_reader $FISHDIR/fish_key_reader
-        set -lx fish_test_helper $FISHDIR/fish_test_helper
+        path is -fx -- $FISHDIR/fish_test_helper
+        and set -lx fish_test_helper $FISHDIR/fish_test_helper
 
         # Note we require Python3.
         python3 $file
diff --git a/tests/pexpects/exit_nohang.py b/tests/pexpects/exit_nohang.py
index 1b5d51a61..b50c36ed8 100644
--- a/tests/pexpects/exit_nohang.py
+++ b/tests/pexpects/exit_nohang.py
@@ -26,6 +26,9 @@ fish_pid = sp.spawn.pid
 # Launch fish_test_helper.
 expect_prompt()
 exe_path = os.environ.get("fish_test_helper")
+if not exe_path:
+    sys.exit(127)
+
 sp.sendline(exe_path + " nohup_wait")
 
 # We expect it to transfer tty ownership to fish_test_helper.
diff --git a/tests/pexpects/fg.py b/tests/pexpects/fg.py
index 628306006..50af50625 100644
--- a/tests/pexpects/fg.py
+++ b/tests/pexpects/fg.py
@@ -2,6 +2,7 @@
 from pexpect_helper import SpawnedProc
 import platform
 import subprocess
+import os
 
 sp = SpawnedProc()
 send, sendline, sleep, expect_prompt, expect_re, expect_str = (
@@ -75,6 +76,10 @@ expect_prompt()
 sendline("jobs")
 expect_prompt("jobs: There are no jobs")
 
+if not os.environ.get("fish_test_helper", ""):
+    import sys
+    sys.exit(127)
+
 # Regression test for #2214: foregrounding from a key binding works!
 sendline(r"bind ctrl-r 'fg >/dev/null 2>/dev/null'")
 expect_prompt()
diff --git a/tests/pexpects/pipeline.py b/tests/pexpects/pipeline.py
index 47aa3f199..a1f74d2a1 100644
--- a/tests/pexpects/pipeline.py
+++ b/tests/pexpects/pipeline.py
@@ -1,5 +1,6 @@
 #!/usr/bin/env python3
 from pexpect_helper import SpawnedProc
+import os
 
 sp = SpawnedProc()
 send, sendline, expect_prompt, expect_str = (
@@ -13,6 +14,10 @@ expect_prompt()
 sendline("function echo_wrap ; /bin/echo $argv ; sleep 0.1; end")
 expect_prompt()
 
+if not os.environ.get("fish_test_helper", ""):
+    import sys
+    sys.exit(127)
+
 for i in range(5):
     sendline(
         "echo_wrap 1 2 3 4 | $fish_test_helper become_foreground_then_print_stderr ; or exit 1"
diff --git a/tests/pexpects/stdin_nonblocking.py b/tests/pexpects/stdin_nonblocking.py
index 935315030..06f5dec22 100644
--- a/tests/pexpects/stdin_nonblocking.py
+++ b/tests/pexpects/stdin_nonblocking.py
@@ -12,6 +12,10 @@ send, sendline, expect_prompt, expect_str, sleep = (
     sp.sleep,
 )
 
+if not os.environ.get("fish_test_helper", ""):
+    import sys
+    sys.exit(127)
+
 # Launch fish_test_helper.
 expect_prompt()
 exe_path = os.environ.get("fish_test_helper")