49 lines
1.5 KiB
Ruby
49 lines
1.5 KiB
Ruby
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require 'set'
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module Sass
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# Provides `Sass.has_feature?` which allows for simple feature detection
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# by providing a feature name.
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module Features
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# This is the set of features that can be detected.
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#
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# When this is updated, the documentation of `feature-exists()` should be
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# updated as well.
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KNOWN_FEATURES = Set[*%w(
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global-variable-shadowing
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extend-selector-pseudoclass
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units-level-3
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at-error
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custom-property
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)]
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# Check if a feature exists by name. This is used to implement
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# the Sass function `feature-exists($feature)`
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#
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# @param feature_name [String] The case sensitive name of the feature to
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# check if it exists in this version of Sass.
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# @return [Boolean] whether the feature of that name exists.
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def has_feature?(feature_name)
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KNOWN_FEATURES.include?(feature_name)
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end
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# Add a feature to Sass. Plugins can use this to easily expose their
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# availability to end users. Plugins must prefix their feature
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# names with a dash to distinguish them from official features.
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#
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# @example
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# Sass.add_feature("-import-globbing")
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# Sass.add_feature("-math-cos")
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#
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#
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# @param feature_name [String] The case sensitive name of the feature to
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# to add to Sass. Must begin with a dash.
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def add_feature(feature_name)
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unless feature_name[0] == ?-
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raise ArgumentError.new("Plugin feature names must begin with a dash")
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end
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KNOWN_FEATURES << feature_name
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end
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end
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extend Features
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end
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