GoogleTest

The GoogleTest crate allows for flexible test assertions using matchers:

use googletest::prelude::*;

#[googletest::test]
fn test_elements_are() {
    let value = vec!["foo", "bar", "baz"];
    expect_that!(value, elements_are!(eq("foo"), lt("xyz"), starts_with("b")));
}

마지막 요소를 '!'로 변경하면 테스트가 실패하고 오류를 정확히 가리키는 구조화된 오류 메시지가 표시됩니다.

---- test_elements_are stdout ----
Value of: value
Expected: has elements:
  0. is equal to "foo"
  1. is less than "xyz"
  2. starts with prefix "!"
Actual: ["foo", "bar", "baz"],
  where element #2 is "baz", which does not start with "!"
  at src/testing/googletest.rs:6:5
Error: See failure output above

Speaker Notes

 This slide should take about 5 minutes.

  • GoogleTest는 Rust 플레이그라운드의 일부가 아니므로 로컬 환경에서 이 예를 실행해야 합니다. cargo add googletest를 사용하여 기존 Cargo 프로젝트에 빠르게 추가하세요.

  • use googletest::prelude::*; 줄은 일반적으로 사용되는 매크로 및 타입을 여러 개 가져옵니다.

  • 이는 일부일 뿐이며 내장된 매처가 많이 있습니다.

  • A particularly nice feature is that mismatches in multi-line strings are shown as a diff:

#[test]
fn test_multiline_string_diff() {
    let haiku = "Memory safete found,\n\
                 Rust's strong typing guides the way,\n\
                 Secure code you'll write.";
    assert_that!(
        haiku,
        eq("Memory safety found,\n\
            Rust's silly humor guides the way,\n\
            Secure code you'll write.")
    );
}

색상으로 구분된 diff를 표시합니다(여기에서는 색상이 표시되지 않습니다).

    Value of: haiku
Expected: is equal to "Memory safety found,\nRust's silly humor guides the way,\nSecure code you'll write."
Actual: "Memory safety found,\nRust's strong typing guides the way,\nSecure code you'll write.",
  which isn't equal to "Memory safety found,\nRust's silly humor guides the way,\nSecure code you'll write."
Difference(-actual / +expected):
 Memory safety found,
-Rust's strong typing guides the way,
+Rust's silly humor guides the way,
 Secure code you'll write.
  at src/testing/googletest.rs:17:5