comprehensive completion generation: native, manpage, --help

Three-strategy pipeline with priority: native completion generators
(e.g. CMD completions nushell) > manpage parsing > --help fallback.
Single `generate` command produces one module-wrapped .nu file per
command. Parallel execution scaled to cores, 200ms timeouts, ELF
string scanning to skip binaries without -h support, native gzip
decompression via camlzip, SYNOPSIS-based subcommand detection,
nix3 manpage strategy, deduplication, nushell builtin exclusion.
This commit is contained in:
atagen 2026-03-21 02:07:46 +11:00
parent 01ccf64efc
commit 7f0ec8ab4d
9 changed files with 937 additions and 265 deletions

View file

@ -3,107 +3,392 @@ open Inshellah.Manpage
open Inshellah.Nushell
let usage () =
Printf.eprintf {|inshellah generate nushell completions from manpages and --help output
Printf.eprintf
{|inshellah - generate nushell completions
Usage:
inshellah manpage FILE Parse a manpage (.1, .1.gz) and emit nushell extern
inshellah manpage-dir DIR Batch-process all manpages under DIR/man1/
inshellah help CMD [ARGS...] Run CMD ARGS --help, parse output, emit nushell extern
inshellah parse-help CMD Read --help text from stdin, emit nushell extern for CMD
inshellah demo Run built-in demo
inshellah generate BINDIR MANDIR -o OUTDIR
Full generation: native completions, manpages, and --help fallback.
One .nu file per command.
inshellah manpage FILE Parse a manpage and emit nushell extern
inshellah manpage-dir DIR Batch-process manpages under DIR
inshellah help CMD [ARGS...] Run CMD ARGS --help, parse and emit extern
inshellah parse-help CMD Read --help text from stdin, emit extern
inshellah demo Run built-in demo
|};
exit 1
(* Extract command name from a manpage filename *)
let command_sections = [1; 8]
let contains_str s sub =
try ignore (Str.search_forward (Str.regexp_string sub) s 0); true
with Not_found -> false
let is_nushell_source text =
String.length text > 20
&& (contains_str text "export extern"
|| contains_str text "export def"
|| (contains_str text "module " && contains_str text "export"))
let filename_of_cmd cmd =
String.map (function
| ('a'..'z' | 'A'..'Z' | '0'..'9' | '-' | '_' | '.') as c -> c | _ -> '-') cmd
let write_file path contents =
let oc = open_out path in output_string oc contents; close_out oc
let cmd_name_of_manpage path =
let base = Filename.basename path in
(* strip .gz if present *)
let base =
if Filename.check_suffix base ".gz" then Filename.chop_suffix base ".gz"
else base
else base in
try Filename.chop_extension base with Invalid_argument _ -> base
let safe_env = lazy (
Array.of_list (
List.filter (fun s ->
not (String.starts_with ~prefix:"DISPLAY=" s
|| String.starts_with ~prefix:"WAYLAND_DISPLAY=" s
|| String.starts_with ~prefix:"DBUS_SESSION_BUS_ADDRESS=" s
|| String.starts_with ~prefix:"XAUTHORITY=" s))
(Array.to_list (Unix.environment ()))))
let run_cmd args timeout_ms =
let (rd, wr) = Unix.pipe () in
let devnull = Unix.openfile "/dev/null" [Unix.O_RDONLY] 0 in
let argv = Array.of_list args in
let pid =
try Unix.create_process_env (List.hd args) argv
(Lazy.force safe_env) devnull wr wr
with Unix.Unix_error _ ->
Unix.close rd; Unix.close wr; Unix.close devnull; -1 in
Unix.close wr; Unix.close devnull;
if pid < 0 then (Unix.close rd; None)
else begin
let buf = Buffer.create 4096 in
let deadline = Unix.gettimeofday () +. (float_of_int timeout_ms /. 1000.0) in
let chunk = Bytes.create 8192 in
let alive = ref true in
(try while !alive do
let remaining = deadline -. Unix.gettimeofday () in
if remaining <= 0.0 then alive := false
else match Unix.select [rd] [] [] (min remaining 0.05) with
| (_ :: _, _, _) ->
let n = Unix.read rd chunk 0 8192 in
if n = 0 then raise Exit
else Buffer.add_subbytes buf chunk 0 n
| _ -> ()
done with Exit -> ());
Unix.close rd;
if not !alive then begin
(try Unix.kill pid Sys.sigkill with Unix.Unix_error _ -> ());
ignore (Unix.waitpid [] pid)
end else
ignore (Unix.waitpid [] pid);
if Buffer.length buf > 0 then Some (Buffer.contents buf) else None
end
let is_executable path =
try let st = Unix.stat path in
st.st_kind = Unix.S_REG && st.st_perm land 0o111 <> 0
with Unix.Unix_error _ -> false
let is_shell_script path =
try
let real = Unix.realpath path in
let ic = open_in_bin real in
let line = (try let b = Bytes.create 256 in
let n = input ic b 0 256 in
let s = Bytes.sub_string b 0 n in
(match String.index_opt s '\n' with Some i -> String.sub s 0 i | None -> s)
with End_of_file -> "") in
close_in ic;
String.length line >= 2 && line.[0] = '#' && line.[1] = '!'
&& let shebang = String.lowercase_ascii line in
List.exists (fun s -> contains_str shebang s)
["bash"; "/sh "; "/sh\n"; "zsh"; "fish"; "nushell"; "/nu "; "/nu\n";
"dash"; "ksh"; "csh"]
with _ -> false
let elf_scan path needles =
let found = Hashtbl.create 4 in
let remaining () = List.filter (fun n -> not (Hashtbl.mem found n)) needles in
(try
let real = Unix.realpath path in
let ic = open_in_bin real in
let magic = Bytes.create 4 in
really_input ic magic 0 4;
if Bytes.get magic 0 = '\x7f' && Bytes.get magic 1 = 'E'
&& Bytes.get magic 2 = 'L' && Bytes.get magic 3 = 'F' then begin
let max_needle = List.fold_left (fun m n -> max m (String.length n)) 0 needles in
let chunk_size = 65536 in
let buf = Bytes.create (chunk_size + max_needle) in
let carry = ref 0 in
let eof = ref false in
while not !eof && remaining () <> [] do
let n = (try input ic buf !carry chunk_size with End_of_file -> 0) in
if n = 0 then eof := true
else begin
let total = !carry + n in
List.iter (fun needle ->
if not (Hashtbl.mem found needle) then begin
let nlen = String.length needle in
let i = ref 0 in
while !i <= total - nlen do
if Bytes.get buf !i = needle.[0] then begin
let ok = ref true in
for j = 1 to nlen - 1 do
if Bytes.get buf (!i + j) <> needle.[j] then ok := false
done;
if !ok then (Hashtbl.replace found needle true; i := total)
else incr i
end else incr i
done
end
) (remaining ());
let new_carry = min max_needle total in
Bytes.blit buf (total - new_carry) buf 0 new_carry;
carry := new_carry
end
done
end;
close_in ic
with _ ->
List.iter (fun n -> Hashtbl.replace found n true) needles);
found
let skip_name name =
String.length name = 0 || name.[0] = '.'
|| String.starts_with ~prefix:"lib" name
|| String.ends_with ~suffix:"-daemon" name
|| String.ends_with ~suffix:"-wrapped" name
|| String.ends_with ~suffix:".so" name
type bin_class = Skip | Try_help | Try_native_and_help
let classify_binary bindir name =
if is_nushell_builtin name || skip_name name then Skip
else
let path = Filename.concat bindir name in
if not (is_executable path) then Skip
else if is_shell_script path then Try_help
else
let scan = elf_scan path ["-h"; "completion"] in
if not (Hashtbl.mem scan "-h") then Skip
else if Hashtbl.mem scan "completion" then Try_native_and_help
else Try_help
let num_cores () =
try
let ic = open_in "/proc/cpuinfo" in
let n = ref 0 in
(try while true do
if String.starts_with ~prefix:"processor" (input_line ic) then incr n
done with End_of_file -> ());
close_in ic; max 1 !n
with _ -> 4
let try_native_completion bin_path =
let patterns = [
[bin_path; "completions"; "nushell"];
[bin_path; "completion"; "nushell"];
[bin_path; "--completions"; "nushell"];
[bin_path; "--completion"; "nushell"];
[bin_path; "generate-completion"; "nushell"];
[bin_path; "--generate-completion"; "nushell"];
[bin_path; "shell-completions"; "nushell"];
] in
let rec go = function
| [] -> None
| args :: rest ->
match run_cmd args 500 with
| Some text when is_nushell_source text -> Some text
| _ -> go rest
in
(* strip .N section suffix *)
try Filename.chop_extension base
with Invalid_argument _ -> base
go patterns
let cmd_manpage file =
let cmd = cmd_name_of_manpage file in
let entries = parse_manpage_file file in
if entries <> [] then
print_string (generate_extern_from_entries cmd entries)
let contents = read_manpage_file file in
let fallback = cmd_name_of_manpage file in
let cmd = match extract_synopsis_command contents with
| Some name -> name | None -> fallback in
if not (is_nushell_builtin cmd) then
let result = parse_manpage_string contents in
if result.entries <> [] then
print_string (generate_extern cmd result)
let cmd_manpage_dir dir =
(* Walk man1/ through man9/ looking for manpages *)
for section = 1 to 9 do
List.iter (fun section ->
let subdir = Filename.concat dir (Printf.sprintf "man%d" section) in
if Sys.file_exists subdir && Sys.is_directory subdir then begin
let files = Sys.readdir subdir in
Array.sort String.compare files;
if Sys.file_exists subdir && Sys.is_directory subdir then
Array.iter (fun file ->
let path = Filename.concat subdir file in
try cmd_manpage path
with _ -> () (* skip unparseable manpages *)
) files
end
done
(try cmd_manpage (Filename.concat subdir file) with _ -> ())
) (Sys.readdir subdir)
) command_sections
let cmd_help args =
match args with
| [] -> Printf.eprintf "error: help mode requires a command name\n"; exit 1
| [] -> Printf.eprintf "error: help requires a command name\n"; exit 1
| cmd :: rest ->
let full_cmd =
String.concat " " (List.map Filename.quote (cmd :: rest @ ["--help"]))
in
let ic = Unix.open_process_in (full_cmd ^ " 2>&1") in
let buf = Buffer.create 4096 in
(try while true do
let line = input_line ic in
Buffer.add_string buf line;
Buffer.add_char buf '\n'
done with End_of_file -> ());
let _ = Unix.close_process_in ic in
let text = Buffer.contents buf in
let cmd_name = Filename.basename cmd in
(match parse_help text with
| Ok r -> print_string (generate_extern cmd_name r)
| Error msg -> Printf.eprintf "parse error for %s: %s\n" cmd_name msg; exit 1)
let name = Filename.basename cmd in
(match run_cmd (cmd :: rest @ ["--help"]) 10_000 with
| None -> Printf.eprintf "no output from %s --help\n" name; exit 1
| Some text ->
(match parse_help text with
| Ok r -> print_string (generate_extern name r)
| Error msg -> Printf.eprintf "parse error for %s: %s\n" name msg; exit 1))
let cmd_parse_help cmd =
let buf = Buffer.create 4096 in
(try while true do
let line = input_line stdin in
Buffer.add_string buf line;
Buffer.add_char buf '\n'
Buffer.add_string buf (input_line stdin); Buffer.add_char buf '\n'
done with End_of_file -> ());
let text = Buffer.contents buf in
(match parse_help text with
(match parse_help (Buffer.contents buf) with
| Ok r -> print_string (generate_extern cmd r)
| Error msg -> Printf.eprintf "parse error for %s: %s\n" cmd msg; exit 1)
let cmd_demo () =
let ls_help =
{|Usage: ls [OPTION]... [FILE]...
List information about the FILEs (the current directory by default).
let process_manpage file =
try
let contents = read_manpage_file file in
let fallback = cmd_name_of_manpage file in
let cmd = match extract_synopsis_command contents with
| Some name -> name | None -> fallback in
if is_nushell_builtin cmd then None
else
let result = parse_manpage_string contents in
if result.entries <> [] then Some (cmd, result) else None
with _ -> None
let manpaged_commands mandir =
let cmds = Hashtbl.create 128 in
List.iter (fun section ->
let subdir = Filename.concat mandir (Printf.sprintf "man%d" section) in
if Sys.file_exists subdir && Sys.is_directory subdir then
Array.iter (fun f -> Hashtbl.replace cmds (cmd_name_of_manpage f) true)
(Sys.readdir subdir)
) command_sections;
cmds
let cmd_generate bindir mandir outdir =
let done_cmds = Hashtbl.create 256 in
let bins = Sys.readdir bindir in
Array.sort String.compare bins;
let manpaged = manpaged_commands mandir in
let max_jobs = num_cores () in
let classified = Array.map (fun name ->
if Hashtbl.mem manpaged name then (name, Skip)
else (name, classify_binary bindir name)
) bins in
let pending = ref [] in
let reap () =
pending := List.filter (fun pid ->
match Unix.waitpid [Unix.WNOHANG] pid with
| (0, _) -> true | _ -> false
| exception Unix.Unix_error (Unix.ECHILD, _, _) -> false
) !pending in
let wait_slot () =
while List.length !pending >= max_jobs do
reap ();
if List.length !pending >= max_jobs then
(try ignore (Unix.wait ()) with Unix.Unix_error _ -> ());
reap ()
done in
Array.iter (fun (name, cls) ->
match cls with
| Skip -> ()
| Try_help | Try_native_and_help ->
wait_slot ();
let pid = Unix.fork () in
if pid = 0 then begin
(try
let path = Filename.concat bindir name in
let native_ok = match cls with
| Try_native_and_help ->
(match try_native_completion path with
| Some src ->
write_file (Filename.concat outdir (filename_of_cmd name ^ ".nu")) src;
true
| None -> false)
| _ -> false in
if not native_ok then begin
let text = match run_cmd [path; "--help"] 200 with
| Some _ as r -> r
| None -> run_cmd [path; "-h"] 200 in
match text with
| None -> ()
| Some t ->
(match parse_help t with
| Ok r when r.entries <> [] ->
write_file (Filename.concat outdir (filename_of_cmd name ^ ".nu"))
(generate_module name r)
| _ -> ())
end;
exit 0
with _ -> exit 1)
end else begin
pending := pid :: !pending;
Hashtbl.replace done_cmds name true
end
) classified;
while !pending <> [] do
(try ignore (Unix.wait ()) with Unix.Unix_error _ -> ());
reap ()
done;
List.iter (fun section ->
let subdir = Filename.concat mandir (Printf.sprintf "man%d" section) in
if Sys.file_exists subdir && Sys.is_directory subdir then begin
let files = Sys.readdir subdir in
Array.sort String.compare files;
Array.iter (fun file ->
match process_manpage (Filename.concat subdir file) with
| None -> ()
| Some (cmd, result) ->
let base = List.hd (String.split_on_char ' ' cmd) in
if Hashtbl.mem done_cmds base then ()
else begin
let outpath = Filename.concat outdir (filename_of_cmd base ^ ".nu") in
if Sys.file_exists outpath then begin
let existing =
let ic = open_in outpath in
let n = in_channel_length ic in
let s = Bytes.create n in
really_input ic s 0 n; close_in ic;
Bytes.to_string s in
let mod_name = module_name_of base in
let use_line = Printf.sprintf "\nuse %s *\n" mod_name in
let base_content =
if contains_str existing use_line then
String.sub existing 0
(Str.search_forward (Str.regexp_string use_line) existing 0)
else existing in
write_file outpath
(String.concat "" [base_content; generate_extern cmd result; use_line])
end else
write_file outpath (generate_module base result)
end
) files
end
) command_sections
let cmd_demo () =
Printf.printf "# Generated by: inshellah demo\n\n";
match parse_help
{|Usage: ls [OPTION]... [FILE]...
-a, --all do not ignore entries starting with .
-A, --almost-all do not list implied . and ..
--block-size=SIZE with -l, scale sizes by SIZE when printing them;
e.g., '--block-size=M'; see SIZE format below
--block-size=SIZE with -l, scale sizes by SIZE when printing
--color[=WHEN] color the output WHEN
-h, --human-readable with -l and -s, print sizes like 1K 234M 2G etc.
--help display this help and exit
--version output version information and exit
|}
in
Printf.printf "# Generated by: inshellah demo\n\n";
(match parse_help ls_help with
| Ok r -> print_string (generate_extern "ls" r)
| Error msg -> Printf.eprintf "parse error: %s\n" msg)
|} with
| Ok r -> print_string (generate_extern "ls" r)
| Error msg -> Printf.eprintf "parse error: %s\n" msg
let () =
let args = Array.to_list Sys.argv |> List.tl in
match args with
match Array.to_list Sys.argv |> List.tl with
| ["generate"; bindir; mandir; "-o"; outdir] -> cmd_generate bindir mandir outdir
| ["manpage"; file] -> cmd_manpage file
| ["manpage-dir"; dir] -> cmd_manpage_dir dir
| "help" :: rest -> cmd_help rest