Specify a whitelist of allowed property and value pairs within declarations.
a { text-transform: uppercase; }
/** ↑ ↑
* These properties and these values */
object
: { "unprefixed-property-name": ["array", "of", "values"], "unprefixed-property-name": ["/regex/", "non-regex"] }
If a property name is found in the object, only its whitelisted property values are allowed. This rule complains about all non-matching values. (If the property name is not included in the object, anything goes.)
If a property name is surrounded with "/"
(e.g. "/^animation/"
), it is interpreted as a regular expression. This allows, for example, easy targeting of shorthands: /^animation/
will match animation
, animation-duration
, animation-timing-function
, etc.
The same goes for values. Keep in mind that a regular expression value is matched against the entire value of the declaration, not specific parts of it. For example, a value like "10px solid rgba( 255 , 0 , 0 , 0.5 )"
will not match "/^solid/"
(notice beginning of the line boundary) but will match "/\\s+solid\\s+/"
or "/\\bsolid\\b/"
.
Be careful with regex matching not to accidentally consider quoted string values and url()
arguments. For example, "/red/"
will match value such as "1px dotted red"
as well as "\"foo\""
and "white url(/mysite.com/red.png)"
.
Given:
{
"transform": ["/scale/"],
"whitespace": ["nowrap"],
"/color/": ["/^green/"]
}
The following patterns are considered violations:
a { whitespace: pre; }
a { transform: translate(1, 1); }
a { -webkit-transform: translate(1, 1); }
a { color: pink; }
a { background-color: pink; }
The following patterns are not considered violations:
a { color: pink; }
a { whitespace: nowrap; }
a { transform: scale(1, 1); }
a { -webkit-transform: scale(1, 1); }
a { color: green; }
a { background-color: green; }
a { background: pink; }