重大变更：-moz-document

Firefox 曾经有一个需要特殊解析的 @-moz-document 规则。随着对其的支持被移除，Sass 正在逐步移除对其解析的支持。

历史上，Sass 对 @-moz-document 规则有特殊的解析方式。随着 Firefox 放弃对其的支持，Sass 也将放弃对特殊解析的支持，并将其视为未知的 at-rule。

有一个例外：仍然允许空的 url 前缀函数，因为这是针对 Firefox 的一个技巧。

  SCSS

  Sass

  CSS

      
      Playground
    SCSS Syntax@-moz-document url-prefix() {
  .error {
    color: red;
  }
}

      
      Playground
    Sass Syntax@-moz-document url-prefix()
  .error
    color: red


CSS Output@-moz-document url-prefix() {
  .error {
    color: red;
  }
}

过渡期过渡期 permalink

Dart Sass: since 1.7.2
LibSass: ✗
Ruby Sass: ✗

首先，我们将为除空 url 前缀技巧之外的所有 @-moz-document 用法发出弃用警告。

在 Dart Sass 2.0 中，@-moz-document 将被视为未知的 at-rule。

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.