Breaking Change: Duplicate Variable Flags
Variables will only allow a single !global
or !default
flag. Duplicate flags never had any additional effect, this just ensures that stylesheets are more consistent.
Phase 1Phase 1 permalink
- Dart Sass
- since 2.0.0
- LibSass
- ✗
- Ruby Sass
- ✗
Starting in Dart Sass 2.0.0, if a single variable declaration has more than one
each !global
or !default
flag, this will be a syntax error. This means that
$var: value !default !default
will be forbidden. $var: value !global !default
will still be allowed.
Transition PeriodTransition Period permalink
- Dart Sass
- since 1.62.0
- LibSass
- ✗
- Ruby Sass
- ✗
Until Dart Sass 2.0.0 is released, multiple copies of a flag just produce deprecation warnings.
Can I Silence the Warnings?Can I Silence the Warnings? permalink
Sass provides a powerful suite of options for managing which deprecation warnings you see and when.
Terse and Verbose ModeTerse and Verbose Mode permalink
By default, Sass runs in terse mode, where it will only print each type of deprecation warning five times before it silences additional warnings. This helps ensure that users know when they need to be aware of an upcoming breaking change without creating an overwhelming amount of console noise.
If you run Sass in verbose mode instead, it will print every deprecation
warning it encounters. This can be useful for tracking the remaining work to be
done when fixing deprecations. You can enable verbose mode using the
--verbose
flag on the command line, or the verbose
option in the
JavaScript API.
⚠️ Heads up!
When running from the JS API, Sass doesn’t share any information across
compilations, so by default it’ll print five warnings for each stylesheet
that’s compiled. However, you can fix this by writing (or asking the author of
your favorite framework’s Sass plugin to write) a custom Logger
that only
prints five errors per deprecation and can be shared across multiple compilations.
Silencing Deprecations in DependenciesSilencing Deprecations in Dependencies permalink
Sometimes, your dependencies have deprecation warnings that you can’t do
anything about. You can silence deprecation warnings from dependencies while
still printing them for your app using the --quiet-deps
flag on the command
line, or the quietDeps
option in the JavaScript API.
For the purposes of this flag, a "dependency" is any stylesheet that’s not just a series of relative loads from the entrypoint stylesheet. This means anything that comes from a load path, and most stylesheets loaded through custom importers.
Silencing Specific DeprecationsSilencing Specific Deprecations permalink
If you know that one particular deprecation isn’t a problem for you, you can
silence warnings for that specific deprecation using the
--silence-deprecation
flag on the command line, or the silenceDeprecations
option in the JavaScript API.
⚠️ Heads up!
This option is only available in the modern JS API.