(bracket_content) @parameter
(quoted_element) @parameter
(unquoted_argument) @parameter

(variable) @variable

[
  (normal_command)
  (if_command)
  (elseif_command)
  (else_command)
  (endif_command)
  (foreach_command)
  (endforeach_command)
  (while_command)
  (endwhile_command)
  (function_command)
  (endfunction_command)
  (macro_command)
  (endmacro_command)
  (message_command)
]@function

[
  "1"
  "ON"
  "YES"
  "TRUE"
  "Y"
  "0"
  "OFF"
  "NO"
  "FALSE"
  "N"
  "IGNORE"
  "NOTFOUND"
  "NOT"
  "AND"
  "OR"
  "COMMAND"
  "POLICY"
  "TARGET"
  "TEST"
  "DEFINED"
  "CACHE"
  "ENV"
  "IN_LIST"
  "EXISTS"
  "IS_NEWER_THAN"
  "IS_DIRECTORY"
  "IS_SYMLINK"
  "IS_ABSOLUTE"
  "MATCHES"
  "LESS"
  "GREATER"
  "EQUAL"
  "LESS_EQUAL"
  "GREATER_EQUAL"
  "STRLESS"
  "STRGREATER"
  "STREQUAL"
  "STRLESS_EQUAL"
  "STRGREATER_EQUAL"
  "VERSION_LESS"
  "VERSION_GREATER"
  "VERSION_EQUAL"
  "VERSION_LESS_EQUAL"
  "VERSION_GREATER_EQUAL" 
  "IN"
  "RANGE"
  "ZIP_LISTS"
  "LISTS"
  "ITEMS"
  "FATAL_ERROR"
  "SEND_ERROR"
  "WARNING"
  "AUTHOR_WARNING"
  "DEPRECATION"
  "NOTICE"
  "STATUS"
  "VERBOSE"
  "DEBUG"
  "TRACE"
  "CHECK_START"
  "CHECK_PASS"
  "CHECK_FAIL"
] @keyword