It would be helpful if bash-language-server could utilize bash-completion to fetch the available switches and arguments for certain commands. I'm not familiar with Typescript myself, unfortunately, so I cannot determine the feasibility of implementing such a feature at this time.

Subcommand and switch completion

For example, if git and its associated Bash completions are installed on the machine, then typing the following into a buffer:

git <ctrl+space> 

would yield the following completions from the language server:

add am archive bisect etc... 

Similarly, typing the following:

git --<ctrl+space> 

would yield the following completions:

--bare --exec-path --exec-path= --git-dir= --help etc... 

Optionally, the server could attempt to fetch results for both git , git -, and git -- (in that order) and show completions for all three possibilities such that they can be easily filtered and selected at a glance. I'm not sure about the performance implications of this behavior, however.

Argument completion

A similar process could allow for argument completion, if the completion function provides it. For example, if openssh and its associated Bash completions are installed, then typing the following:

ssh <ctrl+space> 

would possibly yield the following completions:

127.0.0.1 12.123.123.123 ::1 bar baz.com foo.local github.com localhost 

Future work

If a manpage exists on the system for a specific command (the same one manpage currently used for documentation suggestions in bash-language-server), we could potentially search the manpage for the subcommands/switches provided to us by bash-completion, such that entering the following:

git --h<ctrl+space> 

would allow the user to select --help from the list, and hovering over the --help would parse the git manpage for a section titled --help and display the following:

--help Prints the synopsis and a list of the most commonly used commands. If the option --all or -a is given then all available commands are printed. If a Git command is named this option will bring up the manual page for that command. Other options are available to control how the manual page is displayed. See git-help(1) for more information, because git --help ... is converted internally into git help .... 

This could be done using explainshell for help, as also suggested in #107.