Code review feedback

* Renamed `LibCnbRs` to `WorkspaceBuildpack`
* Renamed `Crate` to `CurrentCrate`
* Updated CHANGELOG.md and doc example

CHANGELOG.md

@@ -14,13 +14,18 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `libcnb-data`:
   - `ExecDProgramOutputKey`, `ProcessType`, `LayerName`, `BuildpackId` and `StackId` now implement `Ord` and `PartialOrd`. ([#658](https://github.com/heroku/libcnb.rs/pull/658))
   - Add `generic::GenericMetadata` as a generic metadata type. Also makes it the default for `BuildpackDescriptor`, `SingleBuildpackDescriptor`, `MetaBuildpackDescriptor` and `LayerContentMetadata`. ([#664](https://github.com/heroku/libcnb.rs/pull/664))
+- `libcnb-test`:
+  - Added the variant `WorkspaceBuildpack` to the `build_config::BuildpackReference` enum which allows any buildpack within the Rust workspace to be referenced for testing. ([#666](https://github.com/heroku/libcnb.rs/pull/666))
+  - Testing of composite buildpacks is now supported using the `WorkspaceBuildpack` variant - **Requires `pack` CLI version `>=0.30`**. ([#666](https://github.com/heroku/libcnb.rs/pull/666))
 
 ### Changed
 
 - Renamed `libcnb-data`'s `Buildpackage` to `PackageDescriptor`. This required changes in many other names across multiple libcnb.rs crates for consistency. See the PR diff for details, but renames should be straightforward and unsurprising. ([#656](https://github.com/heroku/libcnb.rs/pull/656))
 - `libcnb-cargo`:
   - No longer outputs paths for non-libcnb.rs and non-meta buildpacks. ([#657](https://github.com/heroku/libcnb.rs/pull/657))
   - Build output for humans changed slightly, output intended for machines/scripting didn't change. ([#657](https://github.com/heroku/libcnb.rs/pull/657))
+- `libcnb-test`:
+  - Renamed the variant `Crate` to `CurrentCrate` for the `build_config::BuildpackReference` enum which references the buildpack within the Rust Crate currently being tested. ([#666](https://github.com/heroku/libcnb.rs/pull/666))
 
 ## [0.14.0] - 2023-08-18
 

libcnb-test/README.md

@@ -191,13 +191,15 @@ fn dynamic_fixture() {
 Building with multiple buildpacks, using [`BuildConfig::buildpacks`]:
 
 ```rust,no_run
+use libcnb_data::buildpack_id;
 use libcnb_test::{BuildConfig, BuildpackReference, TestRunner};
 
 // #[test]
 fn additional_buildpacks() {
     TestRunner::default().build(
         BuildConfig::new("heroku/builder:22", "test-fixtures/app").buildpacks(vec![
-            BuildpackReference::Crate,
+            BuildpackReference::CurrentCrate,
+            BuildpackReference::WorkspaceBuildpack(buildpack_id!("my-project/buildpack")),
             BuildpackReference::Other(String::from("heroku/another-buildpack")),
         ]),
         |context| {

libcnb-test/src/build_config.rs

@@ -42,7 +42,7 @@ impl BuildConfig {
             cargo_profile: CargoProfile::Dev,
             target_triple: String::from("x86_64-unknown-linux-musl"),
             builder_name: builder_name.into(),
-            buildpacks: vec![BuildpackReference::Crate],
+            buildpacks: vec![BuildpackReference::CurrentCrate],
             env: HashMap::new(),
             app_dir_preprocessor: None,
             expected_pack_result: PackResult::Success,
@@ -51,7 +51,7 @@ impl BuildConfig {
 
     /// Sets the buildpacks (and their ordering) to use when building the app.
     ///
-    /// Defaults to [`BuildpackReference::Crate`].
+    /// Defaults to [`BuildpackReference::CurrentCrate`].
     ///
     /// # Example
     /// ```no_run
@@ -60,7 +60,7 @@ impl BuildConfig {
     /// TestRunner::default().build(
     ///     BuildConfig::new("heroku/builder:22", "test-fixtures/app").buildpacks(vec![
     ///         BuildpackReference::Other(String::from("heroku/another-buildpack")),
-    ///         BuildpackReference::Crate,
+    ///         BuildpackReference::CurrentCrate,
     ///     ]),
     ///     |context| {
     ///         // ...
@@ -251,9 +251,9 @@ impl BuildConfig {
 #[derive(Debug, Clone, Eq, PartialEq)]
 pub enum BuildpackReference {
     /// References the buildpack in the Rust Crate currently being tested.
-    Crate,
+    CurrentCrate,
     /// References a libcnb.rs buildpack within the Rust Workspace that needs to be packaged into a buildpack
-    LibCnbRs(BuildpackId),
+    WorkspaceBuildpack(BuildpackId),
     /// References another buildpack by id, local directory or tarball.
     Other(String),
 }

libcnb-test/src/test_runner.rs

@@ -98,14 +98,14 @@ impl TestRunner {
 
         for buildpack in &config.buildpacks {
             match buildpack {
-                BuildpackReference::Crate => {
+                BuildpackReference::CurrentCrate => {
                     let crate_buildpack_dir = build::package_crate_buildpack(config.cargo_profile, &config.target_triple)
                         .expect("Test references crate buildpack, but crate wasn't packaged as a buildpack. This is an internal libcnb-test error, please report any occurrences");
                     pack_command.buildpack(crate_buildpack_dir.path.clone());
                     buildpack_dirs.push(crate_buildpack_dir);
                 }
 
-                BuildpackReference::LibCnbRs(builpack_id) => {
+                BuildpackReference::WorkspaceBuildpack(builpack_id) => {
                     let buildpack_dir = build::package_buildpack(builpack_id, config.cargo_profile, &config.target_triple)
                         .unwrap_or_else(|_| panic!("Test references buildpack `{builpack_id}`, but this directory wasn't packaged as a buildpack. This is an internal libcnb-test error, please report any occurrences"));
                     pack_command.buildpack(buildpack_dir.path.clone());

libcnb-test/tests/integration_test.rs

@@ -547,7 +547,7 @@ fn address_for_port_when_container_crashed() {
 fn basic_build_with_libcnb_reference_to_single_buildpack() {
     TestRunner::default().build(
         BuildConfig::new("heroku/builder:22", "test-fixtures/procfile").buildpacks(vec![
-            BuildpackReference::LibCnbRs(buildpack_id!("libcnb-test/a")),
+            BuildpackReference::WorkspaceBuildpack(buildpack_id!("libcnb-test/a")),
         ]),
         |context| {
             assert_empty!(context.pack_stderr);
@@ -566,7 +566,7 @@ fn basic_build_with_libcnb_reference_to_single_buildpack() {
 fn basic_build_with_libcnb_reference_to_meta_buildpack() {
     TestRunner::default().build(
         BuildConfig::new("heroku/builder:22", "test-fixtures/procfile").buildpacks(vec![
-            BuildpackReference::LibCnbRs(buildpack_id!("libcnb-test/meta")),
+            BuildpackReference::WorkspaceBuildpack(buildpack_id!("libcnb-test/meta")),
         ]),
         |context| {
             assert_empty!(context.pack_stderr);