fabric

/** * Regex matching color in RGB or RGBA formats (ex: `rgb(0, 0, 0)`, `rgba(255, 100, 10, 0.5)`, `rgba( 255 , 100 , 10 , 0.5 )`, `rgb(1,1,1)`, `rgba(100%, 60%, 10%, 0.5)`) * Also matching rgba(r g b / a) as per new specs * https://developer.mozilla.org/en-US/docs/Web/CSS/color_value/rgb * Formal syntax at the time of writing: * <rgb()> = * rgb( [ <percentage> | none ]{3} [ / [ <alpha-value> | none ] ]? ) | * rgb( [ <number> | none ]{3} [ / [ <alpha-value> | none ] ]? ) * <alpha-value> = <number> | <percentage> * * For learners this is how you can read this regex * Regular expression for matching an rgba or rgb CSS color value * * /^ # Beginning of the string * rgba? # "rgb" or "rgba" * \(\s* # Opening parenthesis and optional whitespace * (\d{0,3} # 0 to three digits R channel * (?:\.\d+)? # Optional decimal with one or more digits * ) # End of capturing group for the first color component * %? # Optional percent sign after the first color component * \s* # Optional whitespace * [\s|,] # Separator between color components can be a space or comma * \s* # Optional whitespace * (\d{0,3} # 0 to three digits G channel * (?:\.\d+)? # Optional decimal with one or more digits * ) # End of capturing group for the second color component * %? # Optional percent sign after the second color component * \s* # Optional whitespace * [\s|,] # Separator between color components can be a space or comma * \s* # Optional whitespace * (\d{0,3} # 0 to three digits B channel * (?:\.\d+)? # Optional decimal with one or more digits * ) # End of capturing group for the third color component * %? # Optional percent sign after the third color component * \s* # Optional whitespace * (?: # Beginning of non-capturing group for alpha value * \s* # Optional whitespace * [,/] # Comma or slash separator for alpha value * \s* # Optional whitespace * (\d{0,3} # Zero to three digits * (?:\.\d+)? # Optional decimal with one or more digits * ) # End of capturing group for alpha value * %? # Optional percent sign after alpha value * \s* # Optional whitespace * )? # End of non-capturing group for alpha value (optional) * \) # Closing parenthesis * $ # End of the string * * The alpha channel can be in the format 0.4 .7 or 1 or 73% * * WARNING this regex doesn't fail on off spec colors. it matches everything that could be a color. * So the spec does not allow for `rgba(30 , 45% 35, 49%)` but this will work anyways for us */ export const reRGBa = () => /^rgba?$\s*(\d{0,3}(?:\.\d+)?%?)\s*[\s|,]\s*(\d{0,3}(?:\.\d+)?%?)\s*[\s|,]\s*(\d{0,3}(?:\.\d+)?%?)\s*(?:\s*[,/]\s*(\d{0,3}(?:\.\d+)?%?)\s*)?$$/i; /** * Regex matching color in HSL or HSLA formats (ex: hsl(0, 0, 0), rgba(255, 100, 10, 0.5), rgba( 255 , 100 , 10 , 0.5 ), rgb(1,1,1), rgba(100%, 60%, 10%, 0.5)) * Also matching rgba(r g b / a) as per new specs * https://developer.mozilla.org/en-US/docs/Web/CSS/color_value/hsl * Formal syntax at the time of writing: * <hsl()> = * hsl( [ <hue> | none ] [ <percentage> | none ] [ <percentage> | none ] [ / [ <alpha-value> | none ] ]? ) * * <hue> = * <number> | * <angle> * * <alpha-value> = * <number> | * <percentage> * * For learners this is how you can read this regex * Regular expression for matching an hsla or hsl CSS color value * * /^hsla?\( // Matches the beginning of the string and the opening parenthesis of "hsl" or "hsla" * \s* // Matches any whitespace characters (space, tab, etc.) zero or more times * (\d{0,3} // Hue: 0 to three digits - start capture in a group * (?:\.\d+)? // Hue: Optional (non capture group) decimal with one or more digits. * (?:deg|turn|rad)? // Hue: Optionally include suffix deg or turn or rad * ) // Hue: End capture group * \s* // Matches any whitespace characters zero or more times * [\s|,] // Matches a space, tab or comma * \s* // Matches any whitespace characters zero or more times * (\d{0,3} // Saturation: 0 to three digits - start capture in a group * (?:\.\d+)? // Saturation: Optional decimal with one or more digits in a non-capturing group * %?) // Saturation: match optional % character and end capture group * \s* // Matches any whitespace characters zero or more times * [\s|,] // Matches a space, tab or comma * \s* // Matches any whitespace characters zero or more times * (\d{0,3} // Lightness: 0 to three digits - start capture in a group * (?:\.\d+)? // Lightness: Optional decimal with one or more digits in a non-capturing group * %?) // Lightness: match % character and end capture group * \s* // Matches any whitespace characters zero or more times * (?: // Alpha: Begins a non-capturing group for the alpha value * \s* // Matches any whitespace characters zero or more times * [,/] // Matches a comma or forward slash * \s* // Matches any whitespace characters zero or more times * (\d*(?:\.\d+)?%?) // Matches zero or more digits, optionally followed by a decimal point and one or more digits, followed by an optional percentage sign and captures it in a group * \s* // Matches any whitespace characters zero or more times * )? // Makes the alpha value group optional * \) // Matches the closing parenthesis * $/i // Matches the end of the string and sets the regular expression to case-insensitive mode * * WARNING this regex doesn't fail on off spec colors. It matches everything that could be a color. * So the spec does not allow `hsl(30 , 45% 35, 49%)` but this will work anyways for us. */ export const reHSLa = () => /^hsla?$\s*([+-]?\d{0,3}(?:\.\d+)?(?:deg|turn|rad)?)\s*[\s|,]\s*(\d{0,3}(?:\.\d+)?%?)\s*[\s|,]\s*(\d{0,3}(?:\.\d+)?%?)\s*(?:\s*[,/]\s*(\d*(?:\.\d+)?%?)\s*)?$$/i; /** * Regex matching color in HEX format (ex: #FF5544CC, #FF5555, 010155, aff) */ export const reHex = () => /^#?(([0-9a-f]){3,4}|([0-9a-f]{2}){3,4})$/i;