test(rust): add regression tests for windows crates (#3695)

Adds regression tests for the Windows-only issue found in
#3693.

Changes:

- Adds to basic regression tests to the `driver_manager` crate tests
which ensure the Windows-only deps are pulled in at build/test time
- Changes the Rust workflow (`rust.yml`) to now also run tests with
default features, in addition to all features. We were previously only
running the tests with all features enabled which was hiding the mistake
originally caught in #3693. Now
we run tests both ways.
- Minor: Adds the Debug trait to the `DriverInfo` struct so the above
tests pass

Author: amoeba

.github/workflows/rust.yml

@@ -171,7 +171,14 @@ jobs:
         run: |
           rustup toolchain install nightly --component clippy
           cargo +nightly clippy --workspace --all-targets --all-features --locked -- -Dwarnings -Zcrate-attr='feature(non_exhaustive_omitted_patterns_lint)'
-      - name: Test
+      - name: Test (Default Features)
+        working-directory: rust
+        # TODO: enable snowflake tests on windows
+        run: >
+          cargo test --all-targets --workspace
+          ${{ matrix.minimal-versions && '--exclude adbc_datafusion' || '' }}
+          ${{ runner.os == 'Windows' && '--exclude adbc_snowflake' || '' }}
+      - name: Test (All Features)
         working-directory: rust
         # TODO: enable snowflake tests on windows
         run: >

rust/driver_manager/src/lib.rs

@@ -160,7 +160,7 @@ struct ManagedDriverInner {
     _library: Option<libloading::Library>,
 }
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 struct DriverInfo {
     lib_path: std::path::PathBuf,
     entrypoint: Option<Vec<u8>>,
@@ -2015,6 +2015,30 @@ mod tests {
         }
     }
 
+    /// Regression test for https://github.com/apache/arrow-adbc/pull/3693
+    /// Ensures driver manager tests for Windows pull in Windows crates. This
+    /// can be removed/replace when more complete tests are added.
+    #[test]
+    fn test_user_config_dir() {
+        let _ = user_config_dir().unwrap();
+    }
+
+    /// Regression test for https://github.com/apache/arrow-adbc/pull/3693
+    /// Ensures driver manager tests for Windows pull in Windows crates. This
+    /// can be removed/replace when more complete tests are added.
+    #[test]
+    #[cfg(target_os = "windows")]
+    fn test_load_driver_from_registry() {
+        use std::ffi::OsStr;
+        let result = load_driver_from_registry(
+            windows_registry::CURRENT_USER,
+            OsStr::new("nonexistent_test_driver"),
+            None,
+        );
+        assert!(result.is_err());
+        assert_eq!(result.unwrap_err().status, Status::NotFound);
+    }
+
     #[test]
     #[cfg_attr(not(feature = "driver_manager_test_lib"), ignore)]
     #[cfg_attr(target_os = "windows", ignore)] // TODO: remove this line after fixing