TextTransform

This shall be a simple extension to provide basic text transformations (like to uppercase, to lowercase) - which are still not included in vscode itself. Because providing just this would be to simple the extension is extensible itself so further, also asynchronous and more complex transformations can easily be added.

Therefore text transformation handlers can be registered at the core of the extension. The core then takes care of the registration at the vscode extension system on the one hand and the handling of the selections on the other hand.

Currently there are three transformations included:

• to uppercase
• to lowercase
• to capitalcase (capitalizing the first letter of each word^*)

^* a word is always starting after a common whitespace character + at the start of the selection

How to contribute a new transformation

Writing a new transformation is easy as pie - you just have to implement the abstract class ´´Transformation´´ and register it afterwards. Handling of (multiple) selections and async processing comes for free!

Step 1: Inherit from ``Transformation```

export class UppercaseTransformer extends Transformation {
    getCommandName(): string {
        return "uppercase"; //This will be needed for registering the command in package.json
    }
    
    transform(input: string, cb: (output: string) => void): void {        
        cb(input.toUpperCase()); //we could also return a string here instead, the callback is just needed in case of asynchronity
    }
}

Step 2: In extension.ts add a line like:

transformers.push(new UppercaseTransformer());

Step 3: In package.json add your command and its title to the contributes hash:

    ...
    "contributes": {
        "commands": [{
            "command": "uppercase",
            "title": "To uppercase"
        },
        ...
    },
    ...

Step 4: Test your code and open a pull request!