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use super::{HttpDate, IF_MODIFIED_SINCE};

crate::http::header::common_header! {
    /// `If-Modified-Since` header, defined
    /// in [RFC 7232 ยง3.3](https://datatracker.ietf.org/doc/html/rfc7232#section-3.3)
    ///
    /// The `If-Modified-Since` header field makes a GET or HEAD request
    /// method conditional on the selected representation's modification date
    /// being more recent than the date provided in the field-value.
    /// Transfer of the selected representation's data is avoided if that
    /// data has not changed.
    ///
    /// # ABNF
    /// ```plain
    /// If-Unmodified-Since = HTTP-date
    /// ```
    ///
    /// # Example Values
    /// * `Sat, 29 Oct 1994 19:43:31 GMT`
    ///
    /// # Examples
    ///
    /// ```
    /// use std::time::{SystemTime, Duration};
    /// use actix_web::HttpResponse;
    /// use actix_web::http::header::IfModifiedSince;
    ///
    /// let mut builder = HttpResponse::Ok();
    /// let modified = SystemTime::now() - Duration::from_secs(60 * 60 * 24);
    /// builder.insert_header(
    ///     IfModifiedSince(modified.into())
    /// );
    /// ```
    (IfModifiedSince, IF_MODIFIED_SINCE) => [HttpDate]

    test_parse_and_format {
        // Test case from RFC
        crate::http::header::common_header_test!(test1, [b"Sat, 29 Oct 1994 19:43:31 GMT"]);
    }
}