feat(style): add support to serialize and deserialize Style using serde

* Add serde as an optional dependency.
* Add feature-gated derives to Color, Modifier and Style.

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## To be released
 
+* Add feature-gated (`serde`) serialization of `Style`.
+
 ## v0.9.5 - 2020-05-21
 
 ### Bug Fixes

Cargo.toml

@@ -31,6 +31,7 @@ rustbox = { version = "0.11", optional = true }
 crossterm = { version = "0.17", optional = true }
 easycurses = { version = "0.12.2", optional = true }
 pancurses = { version = "0.16.1", optional = true, features = ["win32a"] }
+serde = { version = "1", "optional" = true, features = ["derive"]}
 
 [dev-dependencies]
 rand = "0.7"

src/style.rs

@@ -1,6 +1,7 @@
 use bitflags::bitflags;
 
 #[derive(Debug, Clone, Copy, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub enum Color {
     Reset,
     Black,
@@ -24,6 +25,7 @@ pub enum Color {
 }
 
 bitflags! {
+    #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
     pub struct Modifier: u16 {
         const BOLD              = 0b0000_0000_0001;
         const DIM               = 0b0000_0000_0010;
@@ -38,6 +40,7 @@ bitflags! {
 }
 
 #[derive(Debug, Clone, Copy, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Style {
     pub fg: Color,
     pub bg: Color,