Support the reference symbol feature of i18n

[tomoasleep]

The default backend (Backend::Simple) of i18n gem has a feature that allows you to specify translations as a reference to another key.

For example, the following YAML translation data is given:

en:
  sample: :foo.bar
  foo:
    bar:
      run:
        success: Success!

When you evaluate I18n.translate('.sample.run.success') it returns 'Success!'.
This is because that the backend interprets the symbol value :foo.bar corresponding to the key '.sample.run.success' as
the reference of another key '.foo.bar'.

Currently i18n-tasks gem does not support the feature and reports the use of such symbol references as missing keys.

If i18n-task gem will support this feature, I will send a PR :-)
What do you think?

Here's a reproducible example project:

• https://github.com/tomoasleep/i18n-tasks-sample-app

[glebm]

Hi, @tomoasleep! Apologies for the late reply! The goal of this project is to support as much of the i18n gem as possible, so I will merge a PR for this. 👍

[tomoasleep]

@glebm Thanks for replying!
I'm busy now and I'm sorry that It would take time..., but I will send a PR 👍

[rstacruz]

any kind soul want to offer doing this?

[glebm]

Basic requirements:

1. Detect reference keys as unused if the target as unused.
2. Detect reference keys as missing if the target is missing.
3. Copy reference keys as is on add-missing and translate-missing.

[glebm]

Update The basic design describe here turned out to be insufficient

---

A very basic design that doesn't give i18n-tasks full awareness of reference keys, meaning only basic reporting, but achieving all of the basic requirements above:

1. Include all resolved references into used_key_names. What this means for the used references is:

   1. If a reference key is missing, it is reported as such.
   2. If a resolved.* key is missing, it is reported as such.
   3. Both reference and resolved are considered used.

   All unused references are also detected as unused.

   This achieves requirements (1) and (2).

2. Hard-code reference check into add-missing and translate-missing to always copy as-is.

[glebm]

In theory, references should be somewhat supported for find, missing, and unused at this point.

No support yet for: add-missing and translate-missing; finding keys by their resolved name via find; nice reporting.

If you need this feature, please try the version from the reference-keys branch and report here.

[glebm]

Keys can now be find by their resolved name via i18n-tasks find. Reporting also improved slightly.

[glebm]

Released in v0.9.3.