rust_test.bzl

rust_test

load("@rules_rust//rust:rust_test.bzl", "rust_test")

rust_test(name, deps, srcs, data, aliases, allocator_libraries, alwayslink, compile_data, crate,
          crate_features, crate_name, crate_root, edition, env, env_inherit,
          experimental_use_cc_common_link, link_deps, link_std_dylib, lint_config, malloc, platform,
          proc_macro_deps, require_explicit_unstable_features, root_path, rustc_env, rustc_env_files,
          rustc_flags, stamp, unstable_rust_features_config, use_libtest_harness, version,
          zself_profile_events)

Builds a Rust test crate.

Examples:

Suppose you have the following directory structure for a Rust library crate with unit test code in the library sources:

[workspace]/
    WORKSPACE
    hello_lib/
        BUILD
        src/
            lib.rs

hello_lib/src/lib.rs:

#![allow(unused)]
fn main() {
pub struct Greeter {
    greeting: String,
}

impl Greeter {
    pub fn new(greeting: &str) -> Greeter {
        Greeter { greeting: greeting.to_string(), }
    }

    pub fn greet(&self, thing: &str) -> String {
        format!("{} {}", &self.greeting, thing)
    }
}

#[cfg(test)]
mod test {
    use super::Greeter;

    #[test]
    fn test_greeting() {
        let hello = Greeter::new("Hi");
        assert_eq!("Hi Rust", hello.greet("Rust"));
    }
}
}

To build and run the tests, simply add a rust_test rule with no srcs and only depends on the hello_lib rust_library target via the crate attribute:

hello_lib/BUILD:

load("@rules_rust//rust:defs.bzl", "rust_library", "rust_test")

rust_library(
    name = "hello_lib",
    srcs = ["src/lib.rs"],
)

rust_test(
    name = "hello_lib_test",
    crate = ":hello_lib",
    # You may add other deps that are specific to the test configuration
    deps = ["//some/dev/dep"],
)

Run the test with bazel test //hello_lib:hello_lib_test.

Example: test directory

Integration tests that live in the tests directory, they are essentially built as separate crates. Suppose you have the following directory structure where greeting.rs is an integration test for the hello_lib library crate:

[workspace]/
    WORKSPACE
    hello_lib/
        BUILD
        src/
            lib.rs
        tests/
            greeting.rs

hello_lib/tests/greeting.rs:

#![allow(unused)]
fn main() {
extern crate hello_lib;

use hello_lib;

#[test]
fn test_greeting() {
    let hello = greeter::Greeter::new("Hello");
    assert_eq!("Hello world", hello.greeting("world"));
}
}

To build the greeting.rs integration test, simply add a rust_test target with greeting.rs in srcs and a dependency on the hello_lib target:

hello_lib/BUILD:

load("@rules_rust//rust:defs.bzl", "rust_library", "rust_test")

rust_library(
    name = "hello_lib",
    srcs = ["src/lib.rs"],
)

rust_test(
    name = "greeting_test",
    srcs = ["tests/greeting.rs"],
    deps = [":hello_lib"],
)

Run the test with bazel test //hello_lib:greeting_test.

ATTRIBUTES