cmd/tests: Add REM tests.

programs/cmd/tests/test_builtins.cmd

@@ -52,6 +52,20 @@ echo @tab@word
 echo  @tab@word
 echo@tab@@tab@word
 
+echo ------------ Testing rem --------------
+rem Hello
+rem  Hello
+rem   Hello || foo
+rem echo lol
+rem echo foo & echo bar
+@echo on
+rem Hello
+rem  Hello
+rem   Hello || foo
+rem echo lol
+rem echo foo & echo bar
+@echo off
+
 echo ------------ Testing redirection operators --------------
 mkdir foobar & cd foobar
 echo ...stdout redirection

programs/cmd/tests/test_builtins.cmd.exp

@@ -95,6 +95,17 @@ word
 @tab@word
 @space@@tab@word
 @tab@word
+------------ Testing rem --------------
+
+@pwd@>rem Hello@space@
+
+@pwd@>rem  Hello@space@
+
+@pwd@>rem   Hello || foo@space@
+
+@pwd@>rem echo lol@space@
+
+@pwd@>rem echo foo & echo bar@space@
 ------------ Testing redirection operators --------------
 ...stdout redirection
 foo