RGB numbers with a decimal fraction are treated as invalid even though they're valid CSS

[camdecoster]

Description

The CSS spec states that a number is:

Number values are denoted by <number>, and represent real numbers, possibly with a fractional component.

When written literally, a number is either an integer, or zero or more decimal digits followed by a dot (.) followed by one or more decimal digits; optionally, it can be concluded by the letter “e” or “E” followed by an integer indicating the base-ten exponent in scientific notation. It corresponds to the <number-token> production in the CSS Syntax Module [CSS-SYNTAX-3]. As with integers, the first character of a number may be immediately preceded by - or + to indicate the number’s sign.

The value represents a literal number with the value 0. Expressions that merely evaluate to a with the value 0 (for example, calc(0)) do not match ; only literal s do.

As such, color strings using numbers with a decimal fraction should be valid, but that's not what happens currently.

Steps to reproduce

• Load the library (using Codepen, a project, etc.): import cs from "color-string"
• Call the library with a decimal fraction: cs.get.rgb("rgb(1, 2.0, 3)")
• Note that a null value is returned
• Call the library without a decimal fraction: cs.get.rgb("rgb(1, 2, 3)")
• Note that an array is returned

Notes

• This issue stems from the fact that the rgba regex pattern used to parse the number values can't handle decimal fractions
• This might affect other color strings as well

[Qix-]

This should also support e/E for exponent notation then, too. Can you update #78?

[camdecoster]

Want me to go ahead and switch all the regex patterns to handle decimal fractions and scientific notation?

[camdecoster]

I opted to just let it be. That could be updated in a future PR.