Add module-level documentation to the matcher_support, matchers, and prelude modules.

This documentation will be published to https://docs.rs/googletest and helps to explain what is intended to be placed in each of these modules.

PiperOrigin-RevId: 531510595

Author: hovinenb

googletest/src/lib.rs

@@ -23,6 +23,20 @@ pub mod matcher;
 pub mod matcher_support;
 pub mod matchers;
 
+/// Re-exports of the symbols in this crate which are most likely to be used.
+///
+/// This includes:
+///  * All assertion macros,
+///  * Traits and type definitions normally used by tests, and
+///  * All built-in matchers.
+///
+/// Typically, one imports everything in the prelude in one's test module:
+///
+/// ```
+/// mod tests {
+///     use googletest::prelude::*;
+/// }
+/// ```
 pub mod prelude {
     pub use super::matcher::Matcher;
     pub use super::matchers::*;

googletest/src/matcher_support/mod.rs

@@ -12,7 +12,13 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+//! Utilities to facilitate writing matchers.
+//!
+//! Tests normally do not need to import anything from this module. Some of
+//! these facilities could be useful to downstream users writing custom
+//! matchers.
+
 pub(crate) mod count_elements;
 pub mod description;
 pub(crate) mod edit_distance;
-pub(crate) mod zipped_iterator;
+pub(crate) mod zipped_iterator;

googletest/src/matchers/mod.rs

@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+//! All built-in matchers of this crate are in submodules of this module.
+
 pub mod all_matcher;
 pub mod anything_matcher;
 pub mod conjunction_matcher;