test/file: try to fix freezing of test_22566

- wrap the long single scripts

- using `$(repr(fn))` for inserting temp file name

test/file.jl

@@ -1118,7 +1118,16 @@ function test_13559()
     fn = tempname()
     run(`mkfifo $fn`)
     # use subprocess to write 127 bytes to FIFO
-    writer_cmds = "x=open(\"$fn\", \"w\"); for i=1:127 write(x,0xaa); flush(x); sleep(0.1) end; close(x); quit()"
+    writer_cmds = """
+        x = open($(repr(fn)), "w")
+        for i=1:127
+            write(x,0xaa)
+            flush(x)
+            sleep(0.1)
+        end
+        close(x)
+        quit()
+    """
     open(pipeline(`$(Base.julia_cmd()) --startup-file=no -e $writer_cmds`, stderr=STDERR))
     #quickly read FIFO, draining it and blocking but not failing with EOFError yet
     r = open(fn, "r")
@@ -1133,19 +1142,26 @@ function test_13559()
 end
 test_13559()
 end
-@test_throws ArgumentError mkpath("fakepath",-1)
+@test_throws ArgumentError mkpath("fakepath", -1)
 
 # issue #22566
 if !Sys.iswindows()
     function test_22566()
         fn = tempname()
         run(`mkfifo $fn`)
 
-        script = "x = open(\"$fn\", \"w\"); close(x)"
+        script = """
+            x = open($(repr(fn)), "w")
+            write(x, 0x42)
+            flush(x)
+            close(x)
+            quit()
+        """
         cmd = `$(Base.julia_cmd()) --startup-file=no -e $script`
         open(pipeline(cmd, stderr=STDERR))
 
         r = open(fn, "r")
+        @test read(r, Int8) == 66
         close(r)
 
         rm(fn)