cmListFileLexer: Allow command names with one letter (#14181)
Teach the lexer to treat a single letter as an identifier instead of an unquoted argument. Outside of a command invocation, the parser treats an identifier as a command name and an unquoted argument as an error. Inside of a command invocation, the parser treats an identifier as an unquoted argument. Therefore this change to the lexer will make what was previously an error case work with no other behavioral change.
Showing with 11 additions and 2 deletions