Sublime Plugin Text Input - sublimetext

Question

I have been watching OdatNurd youtube plugin dev tutorials on gathering text.
I want to execute a command palette command via a mapped key
The json command file:
[
{
"caption": "A sample command",
"command": "example",
"args": {
// "message": "Sample",
// "position": 0
},
},
]
Key mapping for my command
{ "keys": ["ctrl+3"], "command": "example", "args": {"message": "1"}}
The issue I have is that I have 2 arguments in my sublime-command json file and I don't want to pass one of the values, but execution via the key mapped complains that the command wants 2 argument and I have passed 1.

Answer 1

I don't know which videos you're watching as you didn't include any links, but one option to try would be to use a null value for the option you don't want to send (for some reason?). For example:
{ "keys": ["ctrl+3"], "command": "example", "args": {"message": "1", "position": null}}
In Python, this translates to
example(message="1", position=None)
I don't know the structure of your class ExampleCommand, so I don't know if it'll choke on the null/None, but it's worth trying.

Answer 2

It's a little unclear what might be going wrong for you because you haven't provided the example implementation of the command that you're using. I can come up with a likely scenario for what's going wrong based on the symptoms you've described however.
For the sake of clarity here (now and for anyone that hasn't watched the associated videos), here's an example of the plugin as it appears in the first of the videos you referenced, along with an associated command palette entry and key binding for it:
Plugin
import sublime
import sublime_plugin
class MessageInputHandler(sublime_plugin.TextInputHandler):
def next_input(self, args):
if 'position' not in args:
return PositionInputHandler()
class PositionInputHandler(sublime_plugin.ListInputHandler):
def list_items(self):
return [
('Top of file', 0),
('Botto of file', -1)
]
class ExampleCommand(sublime_plugin.TextCommand):
def run(self, edit, message, position):
if position < 0:
position = self.view.size()
self.view.insert(edit, position, message)
def input(self, args):
if 'message' not in args:
return MessageInputHandler()
elif 'position' not in args:
return PositionInputHandler()
Command palette entry
{ "caption": "An example command", "command": "example" },
Key Binding
{ "keys": ["ctrl+3"], "command": "example", "args": {
"message": "1"
}},
As defined here, the command takes two arguments, message that is some text to insert, and position that is the location to insert it at.
Since the run method declares that the command takes two arguments, in the normal state of affairs executing the command without providing both arguments will cause a Python error because arguments to commands are passed to run(), and without all of the arguments the call to the method is incorrect.
Using the input() method in conjunction with having the command in the command palette changes this behaviour; Internally Sublime will catch the error, notice that the command implements input() and then invoke it to see if it should be prompting the user via the Command Palette for any missing arguments.
The important parts here are that this will only happen if the command is in the command palette, and that the arguments that get prompted for are entirely under the control of the command itself, since Sublime can't make a general determination on what the missing arguments are supposed to represent.
Using the example of the plugin above, executing the command via the command palette entry has it ask you first for the text to insert, and then for the location in the list input handler.
Using the key binding also invokes the command, but now the prompt you get jumps directly to the ListInputHandler asking you where to do the insertion, skipping over the prompt for the text.
Why? Because the implementation of input() inspects the arguments that were provided, and only prompts you for message if the argument isn't given; since the key binding provides that argument, it skips to checking for the position argument, finds it missing, and prompts you for that instead.
Per your original question:
The issue I have is that I have 2 arguments in my sublime-command json file and I don't want to pass one of the values, but execution via the key mapped complains that the command wants 2 argument and I have passed 1.
It's important first to note that regarding the entry in the command palette, the arguments presented there are only used when the command is actually executed via the command palette. When executed via the key binding, nothing about the command palette configuration is used (except that the entry has to exist).
So, all else being equal based on your original question, the key binding should work as expected so long as the input() method exists and knows to ask for the right arguments.
For example, if input() is not defined, then Sublime can't prompt you, and you get an error message:
Traceback (most recent call last):
File "/home/tmartin/local/sublime_text_4101/Lib/python38/sublime_plugin.py", line 1512, in run_
return self.run(edit, **args)
TypeError: run() missing 1 required positional argument: 'position'
Or, if the input() method is defined but doesn't know that it should look for the missing argument and prompt you for it, that will also cause a problem:
def input(self, args):
if 'message' not in args:
return MessageInputHandler()
In this case the method is invoked, but since it's not looking to see if position is an argument that was missing, it falls off the bottom returning None, Sublime doesn't prompt you, and you get the same error as above.
In the comments above you also mentioned this:
I don't think I have explained the problem very well. I have set up a command which I execute using the Sublime standard shift/command/p It uses textinputhandler and a listinputhandler. It, and the associated python plugin work fine using shit/cmd/p but if I set up my own keyboard mapping, I have to provide both arguments (the text and the list entry). I can't find a way of triggering the listinputhandler when a value has been provided by the key mapping even if that value is None
Again, without seeing the code it's hard to say with any exactness what might be happening. However, the fact that this works for you with that command palette entry (providing no arguments) but not from the key binding points to an issue with your input() method.
In particular, input() is called only once, and is expected to return an instance of an InputHandler for a specific argument. The input handler that input() returns is used to prompt for a specific argument, and when the user is done, the next_input() on the input handler is invoked to ask it "where do we go from here?"
As defined in the example plugin above and in the video, the MessageInputHandler responds to this by saying "if the position argument is also missing, ask for that next".
So, if this works from the command palette and not from the key binding, the most likely reason is that the input method is wrong; from the command palette having both items missing causes input() to ask for message, and message then asks for position, whereas from the key binding with message provided, input() must be returning None, stopping it from asking for position and causing your issue.