Quoting

CLI/test uses shell-style quoting and variable expansion for commands, command-lines and control structures.

For Command-Lines ($)

Command-lines are the text that is passed to the shell. They are used to construct commands for the shell to execute.

For command-lines specified in the script, the entire line is passed as-is to the shell (/bin/sh by default), and all unescaping is handled by the shell itself.

The shell will use POSIX-compliant quoting and unescaping rules.

For Internal Commands and Control Structures (set, if, for, etc.)

Internal commands and control structures are not passed to the shell, and are processed by CLI/test itself.

Unescaping rules for characters (eg: \n, \xXX) are applied eagerly at parsing time, while variable references are lazily expanded at runtime.

Quoting Reference

Single Quotes (')

Single quotes preserve the literal value of every character within the quotes. No characters inside single quotes have special meaning, including the dollar sign used for variable references.

# Command-line
$ echo 'Hello $USER'
! Hello $USER

# Internal command
set MESSAGE 'Hello $USER';
$ echo $MESSAGE
! Hello $USER

Double Quotes (")

Double quotes preserve the literal value of most characters, but still allow for variable expansion (e.g., $VAR or ${VAR}).

set USER "username";

# Command-line
$ echo "Hello $USER"
! Hello username

# Internal command
set MESSAGE "Hello $USER";
$ echo $MESSAGE
! Hello username

Backslash Escaping (\)

Backslashes can be used to escape the next character, preserving its literal meaning. This works both inside double quotes and unquoted text.

You can use '$` to escape dollar signs so they do not participate in variable expansion in unquoted text or double-quoted strings.

$ echo "Hello \"World\""
! Hello "World"

$ echo Hello\ World
! Hello World

$ echo Hello \$WORLD
! Hello $WORLD

set MESSAGE "Hello \"World\"";
$ echo $MESSAGE
! Hello "World"

set MESSAGE "Hello\nWorld";
$ echo "$MESSAGE"
! Hello
! World

set MESSAGE "Hello \$WORLD";
$ echo $MESSAGE
! Hello $WORLD

Note that internal commands support additional escaped characters:

Multi-line Commands

You can split long command-lines across multiple lines using either backslashes or quotes:

$ echo "This is a very long command that \
spans multiple lines"
! This is a very long command that spans multiple lines

$ echo "This is another way to
split a command across lines"
! This is another way to
! split a command across lines 

Variable References

Basic Reference ($VAR)

Use $VAR to reference variables:

set FOO bar;
$ echo $FOO
! bar

Explicit Reference (${VAR})

Use ${VAR} when the variable name is followed by text:

set FOO bar;
$ echo ${FOO}123
! bar123

Quoting in Control Structures

Quoting is optional, but important in control structures like for loops and conditional blocks:

# All three of these are equivalent!
for OS in "linux" "macos" "windows" {
    $ uname -a | grep $OS
    %EXIT any
    *
}

for OS in linux macos windows {
    $ uname -a | grep $OS
    %EXIT any
    *
}

set LINUX "linux";
set WINDOWS "windows";
set MACOS "macos";

for OS in "$LINUX" "$MACOS" "$WINDOWS" {
    $ uname -a | grep $OS
    %EXIT any
    *
}