watch flag breaks backend option

[alexbezhan]

Describe the bug

Without watch flag, compilation to js backend works. With watch flag, it gives an error: Unknown argument -baend``

Reproduction Steps

Given this single-file program:

fn main() {
    println('Hello world')
}

Compile it with: v watch -backend js_browser file.v

Expected Behavior

Program is compiled and watch starts.

Current Behavior

Error: Unknown argument -baend``

Possible Solution

So there is some args parsing issue when using watch option.

Additional Information/Context

When omitting the watch option, the above command starts working correctly.

Also, replacing -backend with -b in the above command makes the compilation work. But -b doesn't set the correct backend (probably another bug). It works correctly for -b js, but when used with -b js_browser it sets backend to js(not js_browser).

V version

0.4.10 22c327f

Environment details (OS name and version, etc.)

Mac OS Sonoma 14.3.1

[huly-for-github[bot]]

Connected to Huly®: V_0.6-22936

[gchumillas]

According to the documentation, all options should be placed in the beginning:

$ v help
V is a tool for managing V source code.

Usage:
  v [options] [command] [arguments]

This works:

v -backend js_browser watch file.v

[alexbezhan]

According to the documentation, all options should be placed in the beginning:

$ v help V is a tool for managing V source code.

Usage: v [options] [command] [arguments] This works:

v -backend js_browser watch file.v

Works, thanks. Closing the issue.

[JalonSolov]

It should stay open until we have a better error message.

The problem is that watch needs a parameter to tell it what to watch. It is taking the -backend option as that parameter.

The 2nd problem is that it is also doing something weird with that parameter, since it prints it back out with the ck missing from -backend. Then it reports that as an unknown option.

Very strange...

[gchumillas]

It's confusing, but it's not really a bug. Simply execute the following command:

$ v watch -help
v watch 0.0.2
-----------------------------------------------
Usage: v watch [options] [--silent] [--clear] [--ignore .db] [--add /path/to/a/file.v] [run] program.v

Description: Collect all .v files needed for a compilation, then re-run the compilation when any of the source changes.

Options:
  --vwatchworker            Internal flag. Used to distinguish vwatch manager and worker processes.
  -s, --silent              Be more silent; do not print the watch timestamp before each re-run.
  -c, --clear               Clears the terminal before each re-run.
  -k, --keep                Keep the program running. Restart it automatically, if it exits by itself. Useful for gg/ui apps.
  -a, --add <string>        Add more files to be watched. Useful with `v watch --add=/tmp/feature.v run cmd/v /tmp/feature.v`, if you change *both* the compiler, and the feature.v file.
  -i, --ignore <string>     Ignore files having these extensions. Useful with `v watch --ignore=.db run server.v`, if your server writes to an sqlite.db file in the same folder.
  -o, --only-watch <string>
                            Watch only files matching these globe patterns. Example for a markdown renderer project: `v watch --only-watch=*.v,*.md run .`
  -h, --help                Show this help screen.
  --before <string>         A command to execute *before* each re-run.
  --after <string>          A command to execute *after* each re-run.

The watch utility recognizes the options c and k, but not the rest of the letters (baend) :P

This is the correct usage:

v [v-options] watch [watch-options] file.v

For example:

v -backend js_browser watch -ck file.v

[JalonSolov]

It is a bug, in that it the message given didn't make any sense. Useless error messages are almost worse than none at all.