test-that 0.4.1

A rich assertion and matcher library based on GoogleTest
Documentation
// Copyright 2022 Google LLC
// Copyright 2026 Bradford Hovinen <bradford@hovinen.me>
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

/// Matches anything. This matcher always succeeds.
///
/// This is useful to check if `actual` matches the specific structure (like
/// `Some(...)`)  but without caring about the internal value.
///
/// ```
/// # use test_that::prelude::*;
/// # fn should_pass() -> TestResult<()> {
/// let option = Some("Some value");
/// verify_that!(option, some(anything()))?;
/// #     Ok(())
/// # }
/// # should_pass().unwrap();
/// ```
pub fn anything() -> __internal::AnythingMatcher {
    __internal::AnythingMatcher
}

pub mod __internal {
    use crate::{
        description::Description,
        matcher::{Describable, Matcher, MatcherResult},
    };
    use core::fmt::Debug;

    #[doc(hidden)]
    pub struct AnythingMatcher;

    impl<T: Debug + ?Sized> Matcher<T> for AnythingMatcher {
        fn matches(&self, _: &T) -> MatcherResult {
            MatcherResult::Match
        }
    }

    impl Describable for AnythingMatcher {
        fn describe(&self, matcher_result: MatcherResult) -> Description {
            match matcher_result {
                MatcherResult::Match => "is anything".into(),
                MatcherResult::NoMatch => "never matches".into(),
            }
        }
    }
}

#[cfg(test)]
mod tests {
    use super::anything;
    use crate::prelude::*;

    #[test]
    fn anything_matches_i32() -> TestResult<()> {
        let value = 32;
        verify_that!(value, anything())?;
        Ok(())
    }

    #[test]
    fn anything_matches_str() -> TestResult<()> {
        let value = "32";
        verify_that!(value, anything())?;
        Ok(())
    }

    #[test]
    fn anything_matches_option() -> TestResult<()> {
        let value = Some(32);
        verify_that!(value, some(anything()))?;
        Ok(())
    }
}