Use all features in CI.

.drone.yml

@@ -9,8 +9,8 @@ steps:
     commands:
       - rustup component add clippy rustfmt
       - cargo fmt --check
-      - cargo test
-      - cargo clippy
+      - cargo test --all-features
+      - cargo clippy --all-features
   - name: release
     image: rust
     pull: always

Cargo.toml

@@ -11,6 +11,7 @@ edition = "2021"
 
 [dependencies]
 rand = "0.8"
+serde = { version = "1", optional = true, features = ["derive"]}
 
 [package.metadata.release]
 publish = false

src/geometry.rs

@@ -1,8 +1,12 @@
 //! Support function for 2D geometry
 //!
 
+#[cfg(feature = "serde")]
+use serde::{Deserialize, Serialize};
+
 /// Position on the map
 #[derive(Default, PartialEq, Copy, Clone, Debug, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(Deserialize, Serialize))]
 pub struct Point {
     pub x: usize,
     pub y: usize,
@@ -29,6 +33,7 @@ impl Point {
 
 /// Rectangle region on the map
 #[derive(Hash, PartialEq, Eq, Copy, Clone, Debug)]
+#[cfg_attr(feature = "serde", derive(Deserialize, Serialize))]
 pub struct Rect {
     pub x1: usize,
     pub x2: usize,

src/map.rs

@@ -7,10 +7,15 @@
 //! specific game.
 //!
 
-use super::geometry::{usize_abs, Point, Rect};
 use std::fmt;
 
+#[cfg(feature = "serde")]
+use serde::{Deserialize, Serialize};
+
+use crate::geometry::{usize_abs, Point, Rect};
+
 #[derive(PartialEq, Copy, Clone, Debug, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(Deserialize, Serialize))]
 pub struct Tile {
     is_blocked: bool,
     index: usize,
@@ -30,6 +35,7 @@ pub struct NoData;
 
 /// Map data
 #[derive(Default, Clone)]
+#[cfg_attr(feature = "serde", derive(Deserialize, Serialize))]
 pub struct Map<D: Clone + Default> {
     pub tiles: Vec<Tile>,
     pub width: usize,