tests: ensure some more specific tests work

test.sh

@@ -1610,4 +1610,81 @@ expecting <<EOF
 minishell: *.txt: ambiguous redirect
 EOF
 
+when_run <<EOF "writing to /dev/full"
+echo hi > /dev/full
+echo \$?
+pwd > /dev/full
+echo \$?
+env > /dev/full
+echo \$?
+EOF
+expecting <<EOF
+minishell: echo: write error: No space left on device
+1
+minishell: pwd: write error: No space left on device
+1
+minishell: env: write error: No space left on device
+125
+EOF
+
+when_run <<EOF "writing to /root"
+echo hi > /root/minishell.tmp
+echo \$?
+pwd > /root/minishell.tmp
+echo \$?
+env > /root/minishell.tmp
+echo \$?
+EOF
+expecting <<EOF
+minishell: /root/minishell.tmp: Permission denied
+1
+minishell: /root/minishell.tmp: Permission denied
+1
+minishell: /root/minishell.tmp: Permission denied
+1
+EOF
+
+when_run <<EOF "redirection: same file for input and output"
+cat < hello.txt > hello.txt
+echo \$?
+EOF
+expecting <<EOF
+minishell: hello.txt: No such file or directory
+1
+EOF
+
+when_run <<EOF "redirection: same file for output and input"
+cat > hello.txt < hello.txt
+echo \$?
+ls
+cat hello.txt
+EOF
+expecting <<EOF
+0
+hello.txt
+EOF
+
+when_run <<"EOF" "null expansions"
+echo hi $NOOOOOOOOOOOOOOOOOOOOOOO hello
+echo hi "" hello
+echo hi "$NOOOOOOOOOOOOOOOOOOOOOOO" hello
+echo hi a$NOOOOOOOOOOOOOOOOOOOOOOO hello
+echo hi ""$NOOOOOOOOOOOOOOOOOOOOOOO hello
+echo hi $NOOOOOOOOOOOOOOOOOOOOOOO"" hello
+echo hi '' hello
+echo hi ''$NOOOOOOOOOOOOOOOOOOOOOOO hello
+echo hi $NOOOOOOOOOOOOOOOOOOOOOOO'' hello
+EOF
+expecting <<EOF
+hi hello
+hi  hello
+hi  hello
+hi a hello
+hi  hello
+hi  hello
+hi  hello
+hi  hello
+hi  hello
+EOF
+
 finalize