[tech] Add procmacro as a feature of relations

Author: woshilapin

Cargo.toml

@@ -19,8 +19,9 @@ members = [
 
 [dependencies]
 derivative = "1"
+relations_procmacro = { version = "1", path = "./relations_procmacro/", optional = true }
 thiserror = "1"
 typed_index_collection = "1"
 
-[dev-dependencies]
-relations_procmacro = { version = "1", path = "./relations_procmacro/" }
+[features]
+default = ["relations_procmacro"]

relations_procmacro/tests/01-get-corresponding.rs

@@ -1,7 +1,6 @@
 mod test_utils;
 
 use relations::*;
-use relations_procmacro::*;
 use test_utils::*;
 use typed_index_collection::*;
 

relations_procmacro/tests/02-invalid-weight.rs

@@ -1,7 +1,6 @@
 mod test_utils;
 
 use relations::*;
-use relations_procmacro::*;
 use test_utils::*;
 use typed_index_collection::*;
 

relations_procmacro/tests/02-invalid-weight.stderr

@@ -1,7 +1,7 @@
 error: proc-macro derive panicked
- --> $DIR/02-invalid-weight.rs:8:10
+ --> $DIR/02-invalid-weight.rs:7:10
   |
-8 | #[derive(GetCorresponding)]
+7 | #[derive(GetCorresponding)]
   |          ^^^^^^^^^^^^^^^^
   |
   = help: message: `weight` attribute must be convertible to f64: ParseFloatError { kind: Invalid }

relations_procmacro/tests/03-non-supported-argument.rs

@@ -1,7 +1,6 @@
 mod test_utils;
 
 use relations::*;
-use relations_procmacro::*;
 use test_utils::*;
 use typed_index_collection::*;
 

relations_procmacro/tests/03-non-supported-argument.stderr

@@ -1,7 +1,7 @@
 error: proc-macro derive panicked
- --> $DIR/03-non-supported-argument.rs:8:10
+ --> $DIR/03-non-supported-argument.rs:7:10
   |
-8 | #[derive(GetCorresponding)]
+7 | #[derive(GetCorresponding)]
   |          ^^^^^^^^^^^^^^^^
   |
   = help: message: Only `key = "value"` attributes supported.

relations_procmacro/tests/04-get-corresponding-without-data.rs

@@ -1,7 +1,6 @@
 mod test_utils;
 
 use relations::*;
-use relations_procmacro::*;
 use test_utils::*;
 use typed_index_collection::*;
 

src/lib.rs

@@ -1,7 +1,13 @@
 //! Modeling the relations between objects.
+//!
+//! By default, feature `relations_procmacro` is enabled, exposing macros to
+//! help build relations. See documentation of the crate `relations_procmacro`
+//! for more information.
 
 mod error;
 mod relations;
 
 pub use crate::error::*;
 pub use crate::relations::*;
+#[cfg(feature = "relations_procmacro")]
+pub use relations_procmacro::*;