Struct libcnb_test::IntegrationTest

pub struct IntegrationTest { /* private fields */ }

Main type for libcnb integration tests.

Dependencies

Integration tests require external tools to be available on the host to run:

• pack
• Docker

Example

use libcnb_test::{IntegrationTest, BuildpackReference, assert_contains};

IntegrationTest::new("heroku/buildpacks:20", "test-fixtures/app")
    .buildpacks(vec![
        BuildpackReference::Other(String::from("heroku/openjdk")),
        BuildpackReference::Crate,
    ])
    .run_test(|context| {
        assert_contains!(context.pack_stdout, "---> Maven Buildpack");
        assert_contains!(context.pack_stdout, "---> Installing Maven");
        assert_contains!(context.pack_stdout, "---> Running mvn package");

        context.start_container(&[12345], |container| {
            assert_eq!(
                call_test_fixture_service(
                    container.address_for_port(12345).unwrap(),
                    "Hagbard Celine"
                )
                .unwrap(),
                "enileC drabgaH"
            );
        });
    });

Implementations

impl IntegrationTest

pub fn new(builder_name: impl Into<String>, app_dir: impl AsRef<Path>) -> Self

Creates a new integration test.

Panics

• When the connection to Docker failed
• When the internal Tokio runtime could not be created

pub fn buildpacks(
    &mut self,
    buildpacks: impl Into<Vec<BuildpackReference>>
) -> &mut Self

Sets the buildpacks order.

Defaults to BuildpackReference::Crate.

pub fn target_triple(&mut self, target_triple: impl Into<String>) -> &mut Self

Sets the target triple.

Defaults to x86_64-unknown-linux-musl.

pub fn run_test<F: FnOnce(IntegrationTestContext<'_>)>(&mut self, f: F)

Starts a new integration test run.

This function will copy the application to a temporary directory, cross-compiles this crate, packages it as a buildpack and then invokes pack to build a new Docker image with the buildpacks specified by this integration test instance.

Since this function is supposed to only be used in integration tests, failures are not signalled via Result values. Instead, this function panics whenever an unexpected error occurred to simplify testing code.

Panics

• When the app could not be copied
• When this crate could not be packed as a buildpack
• When the “pack” command unexpectedly fails

Example

use libcnb_test::{IntegrationTest, assert_contains};

IntegrationTest::new("heroku/buildpacks:20", "test-fixtures/app")
    .run_test(|context| {
        assert_contains!(context.pack_stdout, "---> Ruby Buildpack");
        assert_contains!(context.pack_stdout, "---> Installing bundler");
        assert_contains!(context.pack_stdout, "---> Installing gems");
    })