toggle-dwt-checklist.md

toggle-dwt: Implementation Checklist

Companion PR to #3316 (toggle-touchpad). Adds a toggle-dwt action to toggle disable-while-typing on/off at runtime via keybind or IPC.

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Pattern Reference (from toggle-touchpad PR)

The toggle-touchpad PR touches 6 files with +57 −4 lines. The DWT toggle follows the same pattern exactly, with one key difference: instead of toggling the SendEventsMode (on/off), you're toggling the libinput DWT enabled state.

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Files to Change

1. niri-ipc/src/lib.rs — IPC Action enum

What toggle-touchpad did: Added ToggleTouchpad {} variant with doc comment to the Action enum (~line 807).

What to do:

• Add ToggleDwt {} variant to pub enum Action
• Doc comment: /// Toggle disable-while-typing on/off at runtime.
• Place it adjacent to ToggleTouchpad {} for grouping

2. niri-config/src/binds.rs — Config Action enum + IPC mapping

What toggle-touchpad did:

• Added ToggleTouchpad to pub enum Action (~line 108)
• Added niri_ipc::Action::ToggleTouchpad {} => Self::ToggleTouchpad in the From<niri_ipc::Action> impl (~line 661)

What to do:

• Add ToggleDwt variant to pub enum Action
• Add mapping in From<niri_ipc::Action>: niri_ipc::Action::ToggleDwt {} => Self::ToggleDwt

3. src/niri.rs — Runtime state field

What toggle-touchpad did:

• Added pub touchpad_disabled_by_toggle: bool field to pub struct Niri (~line 263)
• Initialised it to false in Niri::new() (~line 2459)
• Passed it through to apply_libinput_settings() in the config-reload path (~line 1636)

What to do:

• Add pub dwt_disabled_by_toggle: bool field to pub struct Niri
• Initialise to false in Niri::new()
• Pass it through to apply_libinput_settings() in the config-reload path

4. src/input/mod.rs — Action handler + libinput application

This is the meatiest file. Three touch points:

4a. apply_libinput_settings() signature & DWT logic

What toggle-touchpad did: Added touchpad_disabled_by_toggle: bool param, then combined it with c.off:

let is_off = c.off || touchpad_disabled_by_toggle;

What to do:

• Add dwt_disabled_by_toggle: bool param to apply_libinput_settings()
• In the touchpad branch, where DWT is applied (currently something like device.config_dwt_set_enabled(c.dwt)), combine with the toggle:

let dwt_enabled = c.dwt && !dwt_disabled_by_toggle;
let _ = device.config_dwt_set_enabled(dwt_enabled);

Note on semantics: The toggle-touchpad PR uses OR logic (off || toggled) because both conditions disable. For DWT, the config dwt flag enables DWT, so the toggle should override it off. The logic is: DWT is enabled only if config says dwt AND the toggle hasn't disabled it. This matches Fireye04's use case — they want DWT on normally but toggled off for gameplay.

4b. Device added handler (~line 229)

What toggle-touchpad did: Passed self.niri.touchpad_disabled_by_toggle to apply_libinput_settings() on device add.

What to do:

• Also pass self.niri.dwt_disabled_by_toggle in the same call

4c. Action handler (~line 722)

What toggle-touchpad did: Added Action::ToggleTouchpad arm that flips the bool and re-applies settings to all touchpads.

What to do:

• Add Action::ToggleDwt arm:

Action::ToggleDwt => {
    self.niri.dwt_disabled_by_toggle = !self.niri.dwt_disabled_by_toggle;
    let config = self.niri.config.borrow();
    for mut device in self.niri.devices.iter().cloned() {
        if device.config_tap_finger_count() > 0 {
            apply_libinput_settings(
                &config.input,
                &mut device,
                self.niri.touchpad_disabled_by_toggle,
                self.niri.dwt_disabled_by_toggle,
            );
        }
    }
}

Note: If the toggle-touchpad PR hasn't landed yet, your branch will need to add the touchpad_disabled_by_toggle param too (or just default it to false). If it has landed, you just extend the existing signature.

5. docs/wiki/Configuration:-Input.md — Input docs

What toggle-touchpad did: Added a tip box under the off setting pointing to the toggle-touchpad action.

What to do:

• Add a similar tip under the dwt setting:

> [!TIP]
> <sup>Since: next release</sup> You can also toggle DWT on/off at runtime
> using the [`toggle-dwt` action](./Configuration:-Key-Bindings.md#toggle-dwt),
> without editing the config.

6. docs/wiki/Configuration:-Key-Bindings.md — Keybinding docs

What toggle-touchpad did: Added a #### toggle-touchpad section at the end with description, example bind, and behaviour notes.

What to do:

• Add #### toggle-dwt section:

#### `toggle-dwt`

<sup>Since: next release</sup>

Toggle disable-while-typing on or off at runtime.
This provides a quick way to disable DWT without editing the config file.

    ```kdl
    binds {
        Mod+F10 { toggle-dwt; }
    }
    ```

The toggle state is combined with the [`dwt` setting](./Configuration:-Input.md#pointing-devices)
in the config: both the config and the toggle must enable DWT for it to be active.
The toggle state resets when niri restarts, and applies to newly hot-plugged touchpads.

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Design Decision: Shared Signature vs Separate Params

If both PRs land, apply_libinput_settings will have two toggle bools:

pub fn apply_libinput_settings(
    config: &niri_config::Input,
    device: &mut input::Device,
    touchpad_disabled_by_toggle: bool,
    dwt_disabled_by_toggle: bool,
)

This is fine for two toggles. If a third arrives (e.g. toggle-dwtp, toggle-natural-scroll), it would be worth refactoring to a struct:

pub struct InputToggleOverrides {
    pub touchpad_off: bool,
    pub dwt_off: bool,
    // future: dwtp_off, natural_scroll_off, etc.
}

But that's a future concern — keep it simple for now.

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Test Plan

• Bind toggle-dwt to a key, verify DWT toggles off (touchpad works while typing) and back on
• Test via IPC: niri msg action toggle-dwt
• Verify interaction with config dwt setting (toggle has no effect if dwt is not set in config)
• Hot-plug a touchpad while DWT is toggled off, verify DWT stays off
• Verify toggle-touchpad and toggle-dwt work independently

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PR Description Template

## Summary

* Adds a new `toggle-dwt` action to toggle disable-while-typing on/off at runtime
* Can be bound to a key or invoked via IPC with `niri msg action toggle-dwt`
* The toggle state is combined with the config's `dwt` setting — both must
  enable DWT for it to be active

Companion to #3316 — extends the same runtime toggle pattern to DWT.

Requested by @Fireye04 in #3316 (comment).

## Notes

* State resets on restart
* Applies to newly hot-plugged touchpads

## Test plan

* Bind `toggle-dwt` to a key and verify it toggles DWT
* Test via IPC: `niri msg action toggle-dwt`
* Verify interaction with config `dwt` setting
* Hot-plug a touchpad while toggled off and verify it stays off