diff --git a/tests/checks/noshebang.fish b/tests/checks/noshebang.fish
index c392b2d1d..d79c8a971 100644
--- a/tests/checks/noshebang.fish
+++ b/tests/checks/noshebang.fish
@@ -1,11 +1,11 @@
-# RUN: %fish %s
+# RUN: %fish -C'set -g fish (builtin realpath %fish)' %s
 
 # Test for shebangless scripts - see 7802.
 
 set testdir (mktemp -d)
 cd $testdir
 
-touch file
+$fish -c 'true > file'
 chmod a+x file
 
 function runfile
@@ -23,21 +23,21 @@ function runfile
 end
 
 # Empty executable files are 'true'.
-true >file
-sleep 0.1
 runfile
 #CHECK: 0
 #CHECK: 0
 
 # Files without NUL are 'true' as well.
-echo -e -n '#COMMENT\n#COMMENT' >file
+# NOTE: We redirect in a new process because the file must be *closed*
+# before it can be run. On some systems that doesn't happen quickly enough.
+$fish -c "echo -e -n '#COMMENT\n#COMMENT' >file"
+sleep 0.1
 runfile
 #CHECK: 0
 #CHECK: 0
 
 # Never implicitly pass files ending with .fish to /bin/sh.
-true >file.fish
-sleep 0.1
+touch file.fish
 chmod a+x file.fish
 set -g fish_use_posix_spawn 0
 ./file.fish
@@ -59,14 +59,14 @@ rm file.fish
 
 # On to NUL bytes.
 # The heuristic is that there must be a line containing a lowercase letter before the first NUL byte.
-echo -n -e 'true\n\x00' >file
+$fish -c "echo -n -e 'true\n\x00' >file"
 sleep 0.1
 runfile
 #CHECK: 0
 #CHECK: 0
 
 # Doesn't meet our heuristic as there is no newline.
-echo -n -e 'true\x00' >file
+$fish -c "echo -n -e 'true\x00' >file"
 sleep 0.1
 runfile
 #CHECK: 126
@@ -80,7 +80,7 @@ runfile
 #CHECKERR: {{.*}}
 
 # Doesn't meet our heuristic as there is no lowercase before newline.
-echo -n -e 'NOPE\n\x00' >file
+$fish -c "echo -n -e 'NOPE\n\x00' >file"
 sleep 0.1
 runfile
 #CHECK: 126