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Specify a list of allowed property and value pairs within declarations.

a { text-transform: uppercase; }
/** ↑ ↑
* These properties and these values */

The message secondary option can accept the arguments of this rule.


object: { "unprefixed-property-name": ["array", "of", "values", "/regex/", /regex/]|"value"|"/regex/"|/regex/ }

If a property name is found in the object, only the listed 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 "\"red\"" and "white url(/".


"transform": ["/scale/"],
"whitespace": "nowrap",
"/color/": ["/^green/"]

The following patterns are considered problems:

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 problems:

a { whitespace: nowrap; }
a { transform: scale(1, 1); }
a { -webkit-transform: scale(1, 1); }
a { color: green; }
a { background-color: green; }