feat: add describe feature

That way users can more precisely decide what they want to use.
Note that spec-parsing is so foundational that it's always included.
Those who don't need it nor need describe don't need the crate in the
fist place.

Author: Byron

gix-revision/Cargo.toml

@@ -13,6 +13,11 @@ rust-version = "1.65"
 doctest = false
 
 [features]
+default = ["describe"]
+
+## `git describe` functionality
+describe = []
+
 ## Data structures implement `serde::Serialize` and `serde::Deserialize`.
 serde = [ "dep:serde", "gix-hash/serde", "gix-object/serde" ]
 

gix-revision/src/lib.rs

@@ -9,7 +9,9 @@
 #![deny(missing_docs, rust_2018_idioms, unsafe_code)]
 
 ///
+#[cfg(feature = "describe")]
 pub mod describe;
+#[cfg(feature = "describe")]
 pub use describe::function::describe;
 
 ///

gix-revision/tests/revision.rs

@@ -1,3 +1,4 @@
+#[cfg(feature = "describe")]
 mod describe;
 mod spec;
 pub type Result<T = ()> = std::result::Result<T, Box<dyn std::error::Error + 'static>>;

justfile

@@ -77,6 +77,7 @@ check:
     cargo check -p gix-credentials --features serde
     cargo check -p gix-sec --features serde
     cargo check -p gix-revision --features serde
+    cargo check -p gix-revision --no-default-features --features describe
     cargo check -p gix-mailmap --features serde
     cargo check -p gix-url --all-features
     cargo check -p gix-features --all-features