* Add fatal/futureDeprecations to Dart API
This adds a new `Deprecation` class that specifies an ID for each
deprecated feature along with what Dart Sass version deprecated it.
The compile functions allow you to pass a set of `fatalDeprecations`
that will cause an error instead of a warning. You can also pass a set
of `futureDeprecations`, which let you opt-in to deprecations (like
`@import`) early.
* Add future deprecation for `@import`
* Add flags
* Merge colorUnits and randomWithUnits
* Update changelogs and pubspecs
* Add tests
* Use isFuture instead of deprecatedIn == null
* Split warnForDeprecation from warn
* Add missing word to error message
Instead, we create a single zone-scoped object that's visible for the
entire lifespan of the visitor, and which exposes evaluation internals
which can be updated as direct field modifications.
These getters are only available through the sass_api package. This
will allow the Sass embedded compiler to more explicitly send the
color information it has on hand.
Rather than constructing this explicitly to match Node Sass's API, we
construct it with canonical URLs and convert it into the format
expected by the Node Sass API (a mix of paths and URLs) in the
compatibility layer.
In addition to being useful for users of Sass, this will make it
possible for core Sass functions to produce warnings without needing
an explicit reference to the evaluator.
The automatic @charset adding is useful in general, but there are
consistently cases where it trips up naïve downstream tools. This
option makes it easier for users to control when it occurs.
These can be passed as an ImportCache now, so they make the API more
confusing for relatively little benefit.
This also changes the const AsyncImportCache.none field to a non-const
AsyncImportCache.none() constructor. The const field didn't make sense
for a couple reasons: first, it wouldn't use a user's custom logger;
and second, it couldn't cache any relative imports, which were still
possible when the initial file was loaded from disk.
This allows us to support asynchronous importers and, eventually,
functions without breaking synchronous support. The copies were made
manually, but the eventual plan is to auto-generate the synchronous
versions by stripping all asynchrony from the async versions.
See #9
