Centralized directory references for input/output/layouts/data/includes, changes Virtual Templates to be input dir relative.

[zachleat]

Preparation for #67 and #1503 and #2307.
Assisting on #1612 (making virtual template paths relative to input dir).

The biggest practical change here is that you’ll be able to reference Eleventy’s full resolved directories in plugins and configuration files. This will include values set via command line arguments #2729.

Command Line

However, if you pass --input or --output directories in on the command line, the values will be correct #2729, e.g. npx @11ty/eleventy --input=content:

export default function(eleventyConfig) {
  eleventyConfig.directories.input; // has "./content/"
};

When returning dir in your config:

This works as expected with plugins. Use addPlugin to get the correct values (plugins run in a second stage).

export default function(eleventyConfig) {
  // Plugins run in a second stage, so we have access to the return object data below
  eleventyConfig.addPlugin(eleventyConfig => {
    // These values always have a trailing slash (if directory); always posix-style forward-slash paths
    eleventyConfig.directories.input; // has "./content/"
    eleventyConfig.directories.output; // has "./_site/"

    // includes, data, layouts directories (input dir relative) are normalized to project root relative.
    eleventyConfig.directories.includes; // has "./content/_includes/
    eleventyConfig.directories.layouts; // is falsy (not specified)
    eleventyConfig.directories.data; // has "./content/_data/"
  });

  return {
    dir: {
      input: "content",
      includes: "_includes",
      data: "_data",
      output: "_site",
    }
  }
};

If you don’t use addPlugin, you’ll get the wrong values. (Fixed with new config export #3246)

export default function(eleventyConfig) {
  // WARNING: this will be wrong if you return an object in your config file
  eleventyConfig.directories.input; // has "./"

  return {
    dir: {
      input: "content",
      includes: "_includes",
      data: "_data",
      output: "_site",
    }
  }
};

[Zearin]

Ooh, cool! :D

I especially love the simplified constructors! 🥳

[zachleat]

Shipping with 3.0.0-alpha.6

[zachleat]

• Make sure we document the eleventy.directories Eleventy supplied data here: https://www.11ty.dev/docs/data-eleventy-supplied/#eleventy-variable via 2.0.2+ https://github.com/11ty/eleventy-img/blob/d9723c59c94b93cfc05efbffd61efef7d19906e8/eleventy-image.webc#L74