TypeScript typings

[MickL]

Handlebars contains TypeScript typings which totally get lost by using this module. Could you add typings that extend handlebars?

[gastonrobledo]

You can do it if you want, and submit a PR ;)

[toverux]

Hi, for people like me who can't bear using an any-typed library :

declare module 'handlebars-async-helpers' {
    import * as hbs from 'handlebars';

    type Handlebars = typeof hbs;

    function asyncHelpers(handlebars: Handlebars): asyncHelpers.AsyncHandlebars;

    namespace asyncHelpers {
        // At least an empty namespace is necessary for allowing "import * as" when allowSyntheticDefaultImports is
        // false. But we'll export our custom types too, so they can be imported too, they can be useful.

        type AsyncTemplateDelegate<Context> = (context: Context, options?: hbs.RuntimeOptions) => Promise<string>;

        type AsyncHandlebars = Omit<Handlebars, 'compile'> & {
            // CompileOptions is not explicitly imported because it's transient in the scope due to how it's declared in
            // Handlebars.
            compile<Context = unknown>(input: any, options?: CompileOptions): AsyncTemplateDelegate<Context>;
        }
    }

    export = asyncHelpers;
}

Put this in a .d.ts file that your TypeScript tsconfig.json is configured to read, ex:

{
  "include": ["./stubs/**.d.ts"] // That's where I place my .d.ts for untyped libraries
}

If you have allowSyntheticDefaultImports enabled: import asyncHelpers from 'handlebars-async-helpers';
If not: import * as asyncHelpers from 'handlebars-async-helpers';

Note to the author: I don't have time to make a PR but feel free to include this in your project if you want. Basically you'll just have to add a types entry pointing to the .d.ts in your published package.json.