KRunner JavaScript Eval

This node script allows running JavaScript code from your KRunner. It uses DBus to communicate with KRunner.

Installation

NixOS with flakes

To install on a flake-based NixOS system:

{
  inputs = {
    nixpkgs = {
      url = "github:NixOS/nixpkgs/nixos-unstable";
    };
    # Add this repository as an input.
    plasma-runner-js-eval = {
      url = "github:opl-/plasma-runner-js-eval";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  # Add the input to the arguments.
  outputs = { nixpkgs, plasma-runner-js-eval, ... }: {
    nixosConfigurations = {
      hostname = nixpkgs.lib.nixosSystem {
          system = "x86_64-linux";
          modules = [
            { pkgs, ... }: {
              # Add the package to nixpkgs using an overlay.
              nixpkgs.overlays = [ plasma-runner-js-eval.overlays.default ];

              users.users.opl = {
                # Add it to user packages.
                packages = [
                  pkgs.plasma-runner-js-eval
                ];
              };
            }
          ];
        };
    };
  };
}

After rebuilding the system you can enable the service with systemctl --user enable plasma-runner-js-eval.

Manually

Alternatively, you can install this script manually by running the following commands:

git clone https://github.com/opl-/plasma-runner-js-eval.git
cd plasma-runner-js-eval
npm install
node lib/index.js

In order for KRunner to be aware of this runner, you need to link plasma-runner-js-eval.desktop to ~/.local/share/kservices5/ or equivalent. You may also need to enable the JavaScript Eval runner in KRunner settings.

You can also use the plasma-runner-js-eval.service file as a template for a systemd user service. Copy it to ~/.config/systemd/user/ or equivalent, change /path/to/program inside to point to the path of this repository, then enable it with systemctl --user enable plasma-runner-js-eval to make it start on user login.

Usage

Start your query with > to signal that you want to run JavaScript, then write your code. It will be continuously ran as you type, immediately reporting errors or the last returned value in your script. For example:

>'JavaScript'.length shows 10

>'JavaScript'.toLowerCase() shows 'javascript'

You can select the JavaScript Eval match to save the result into the $ variable. For example:

>'JavaScript'.toLowerCase()
>$.slice(0, 4)

Returns 'java' as your result. You can also set global variables and access them in later queries:

>x = [1, 2]
>x[1]

This results in 2. You can then use >>new to reset the global environment to its defaults.

Built-in functions

There's a number of built-in functions to extend functionality and ease writing quick scripts.

log(...args: any) => any | any[]

Prints the passed in objects in a notification and returns the passed in arguments. If more than one argument is passed, the arguments are treated as a single array, affecting also the return value.

require(what: string) => any

A limited version of the Node.js require() function. what specifies the requested module. The allowed modules are:

• crypto
• path
• querystring
• string_decoder
• url

makeArr(length: number, entryGenerator: (index: number, array: any[], ...args: any[]) => any, ...args: any) => any[]

Generates an array by calling the entryGenerator function length number of times and pushing the returned values into the array. The entryGenerator function is called with arguments:

• index - Current index
• array - The array being generated
• ...args - List of arguments that were passed to the makeArr function after the generator

range(start: number, end?: number, step?: number) => number[]

Generates an array of numbers ranging from start to end, using the increment of step.

If end is missing, it defaults to 0. If step is missing or 0, it defaults to 1 if end > start, or -1 if end < start.

If step takes takes the range in the direction opposite of end, an empty array is returned.

sum(...args: number | string) => number

Returns the sum of passed items, flattning passed arrays and converting strings into floats.

randF(numberA: number, numberB?: number) => number

Returns a random number:

• If numberB is specified, between numberA and exclusive numberB
• Otherwise between 0 and exclusive numberA

rand(numberA: number, numberB?: number) => number

Returns a random integer number:

• If numberB is specified, between numberA and exclusive numberB
• Otherwise between 0 and exclusive numberA

copy(...args: any) => any | any[]

Stringifies and puts the passed in argument into the clipboard using Klipper's DBus interface, then returns the argument. If more than one argument is passed, the arguments are treated as a single array, also affecting the return value.

paste(index?: number | string) => string

Returns the clipboard entry at index or the most recent entry if index cannot be converted into a number.

deg(degrees: number) => number

Converts degrees to radians.

rad(radians: number) => number

Converts radians to degrees.