Add FromStr for DynamicColor and static colors

This makes it easier to parse them from a string with more concise
code and not requiring a separate import of `parse_color`.

CHANGELOG.md

@@ -15,6 +15,10 @@ You can find its changes [documented below](#020-2024-12-17).
 
 This release has an [MSRV][] of 1.82.
 
+###
+
+* Added `FromStr` impl for `AlphaColor`, `DynamicColor`, `OpaqueColor`, `PremulColor`. ([#111][] by [@waywardmonkeys][])
+
 ### Changed
 
 * Don't enable `serde`'s `std` feature when enabling our `std` feature. ([#108][] by @waywardmonkeys][])

color/src/parse.rs

@@ -9,7 +9,10 @@ use core::fmt;
 use core::str;
 use core::str::FromStr;
 
-use crate::{AlphaColor, ColorSpaceTag, DynamicColor, Flags, Missing, Srgb};
+use crate::{
+    AlphaColor, ColorSpace, ColorSpaceTag, DynamicColor, Flags, Missing, OpaqueColor, PremulColor,
+    Srgb,
+};
 
 // TODO: maybe include string offset
 /// Error type for parse errors.
@@ -521,7 +524,6 @@ pub fn parse_color_prefix(s: &str) -> Result<(usize, DynamicColor), ParseError>
     }
 }
 
-// Arguably this should be an implementation of FromStr.
 /// Parse a color string in CSS syntax into a color.
 ///
 /// This parses the entire string; trailing characters cause an
@@ -543,6 +545,42 @@ pub fn parse_color(s: &str) -> Result<DynamicColor, ParseError> {
     }
 }
 
+impl FromStr for DynamicColor {
+    type Err = ParseError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        parse_color(s)
+    }
+}
+
+impl<CS: ColorSpace> FromStr for AlphaColor<CS> {
+    type Err = ParseError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        parse_color(s).map(DynamicColor::to_alpha_color)
+    }
+}
+
+impl<CS: ColorSpace> FromStr for OpaqueColor<CS> {
+    type Err = ParseError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        parse_color(s)
+            .map(DynamicColor::to_alpha_color)
+            .map(AlphaColor::discard_alpha)
+    }
+}
+
+impl<CS: ColorSpace> FromStr for PremulColor<CS> {
+    type Err = ParseError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        parse_color(s)
+            .map(DynamicColor::to_alpha_color)
+            .map(AlphaColor::premultiply)
+    }
+}
+
 /// Parse 4-bit color channels from a hex-encoded string.
 ///
 /// Returns the parsed channels and the byte offset to the remainder of the string (i.e., the