Implement PyStubType for either::Either (with minor revise) (#212)

Minor revise for #207

Summary by Copilot
-------------------

This pull request introduces support for the `either` crate in the
`pyo3-stub-gen` project, enabling the use of `either::Either` types in
Python stub generation. It also includes minor fixes to existing test
cases for improved clarity and correctness.

### Integration of the `either` crate:

*
[`Cargo.toml`](diffhunk://#diff-2e9d962a08321605940b5a657135052fbcef87b5e360662bb527c96d9a615542R22):
Added `either` as a dependency in the workspace and included it as an
optional feature in `pyo3-stub-gen`. The default features now include
`either`.
[[1]](diffhunk://#diff-2e9d962a08321605940b5a657135052fbcef87b5e360662bb527c96d9a615542R22)
[[2]](diffhunk://#diff-d2fe0506288d6d1bb990e8185c26e0cdf07ee85787eb78c2bb3d60b70bf88eb0R21)
[[3]](diffhunk://#diff-d2fe0506288d6d1bb990e8185c26e0cdf07ee85787eb78c2bb3d60b70bf88eb0L33-R36)
*
[`pyo3-stub-gen/src/stub_type.rs`](diffhunk://#diff-bec31605b52ecbf7a424c6bcc8dfcf155d211d25316e27ba0945b49284470ae8R8-R10):
Added a new module `either` gated behind the `either` feature flag.
*
[`pyo3-stub-gen/src/stub_type/either.rs`](diffhunk://#diff-5d12c671f041e17061b398055bb9cb24b0360e7af721e1985f863a49b0e446dbR1-R44):
Implemented support for `either::Either<L, R>` in stub generation by
defining `type_input` and `type_output` methods that map `Either` to
Python's `typing.Union`.

### Test case fixes:

*
[`pyo3-stub-gen/src/util.rs`](diffhunk://#diff-1c01740ca518ff53dff74391ba7e3427fba3221cc3c19de143bcf2568f253e87L114-R116):
Updated test cases to pass string literals directly instead of
references, improving readability and correctness.

---------

Co-authored-by: YuantianDing <[email protected]>

Author: termoshtt

Cargo.lock

@@ -19,6 +19,7 @@ license = "MIT OR Apache-2.0"
 readme = "README.md"
 
 [workspace.dependencies]
+either = "1.15.0"
 ahash = "0.8.11"
 anyhow = "1.0.98"
 chrono = "0.4.40"

Cargo.toml

@@ -18,6 +18,7 @@ log.workspace = true
 maplit.workspace = true
 num-complex.workspace = true
 numpy = { workspace = true, optional = true }
+either = { workspace = true, optional = true }
 pyo3.workspace = true
 serde.workspace = true
 toml.workspace = true
@@ -30,5 +31,6 @@ path = "../pyo3-stub-gen-derive"
 test-case.workspace = true
 
 [features]
-default = ["numpy"]
+default = ["numpy", "either"]
 numpy = ["dep:numpy"]
+either = ["dep:either"]

examples/mixed/Cargo.lock

@@ -5,6 +5,9 @@ mod pyo3;
 #[cfg(feature = "numpy")]
 mod numpy;
 
+#[cfg(feature = "either")]
+mod either;
+
 use maplit::hashset;
 use std::{collections::HashSet, fmt, ops};
 

examples/mixed_sub/Cargo.lock

@@ -0,0 +1,44 @@
+use std::collections::HashSet;
+
+use super::{ModuleRef, PyStubType, TypeInfo};
+
+impl<L: PyStubType, R: PyStubType> PyStubType for either::Either<L, R> {
+    fn type_input() -> TypeInfo {
+        let TypeInfo {
+            name: name_l,
+            import: import_l,
+        } = L::type_input();
+        let TypeInfo {
+            name: name_r,
+            import: import_r,
+        } = R::type_input();
+
+        let mut import: HashSet<ModuleRef> = import_l.into_iter().chain(import_r).collect();
+
+        import.insert("typing".into());
+
+        TypeInfo {
+            name: format!("typing.Union[{name_l}, {name_r}]"),
+            import,
+        }
+    }
+    fn type_output() -> TypeInfo {
+        let TypeInfo {
+            name: name_l,
+            import: import_l,
+        } = L::type_output();
+        let TypeInfo {
+            name: name_r,
+            import: import_r,
+        } = R::type_output();
+
+        let mut import: HashSet<ModuleRef> = import_l.into_iter().chain(import_r).collect();
+
+        import.insert("typing".into());
+
+        TypeInfo {
+            name: format!("typing.Union[{name_l}, {name_r}]"),
+            import,
+        }
+    }
+}

examples/mixed_sub_multiple/Cargo.lock

@@ -111,9 +111,9 @@ mod test {
         pyo3::prepare_freethreaded_python();
         Python::with_gil(|py| {
             // str
-            assert_eq!("'123'", fmt_py_obj(py, &"123"));
-            assert_eq!("\"don't\"", fmt_py_obj(py, &"don't"));
-            assert_eq!("'str\\\\'", fmt_py_obj(py, &"str\\"));
+            assert_eq!("'123'", fmt_py_obj(py, "123"));
+            assert_eq!("\"don't\"", fmt_py_obj(py, "don't"));
+            assert_eq!("'str\\\\'", fmt_py_obj(py, "str\\"));
             // bool
             assert_eq!("True", fmt_py_obj(py, true));
             assert_eq!("False", fmt_py_obj(py, false));