Add target triple to buildpack output path

.github/workflows/ci.yml

@@ -71,4 +71,4 @@ jobs:
         working-directory: ./examples/basics
       - name: Pack build using examples/basics
         # Uses a non-libc image to validate the static musl cross-compilation.
-        run: pack build example-basics --builder cnbs/sample-builder:alpine --buildpack target/buildpack/debug/libcnb-examples_basics --path examples/
+        run: pack build example-basics --builder cnbs/sample-builder:alpine --buildpack target/buildpack/x86_64-unknown-linux-musl/debug/libcnb-examples_basics --path examples/

CHANGELOG.md

@@ -7,6 +7,8 @@ separate changelogs for each crate were used. If you need to refer to these old
 ## [Unreleased]
 
 - `libcnb-package`: Add cross-compilation assistance for Linux `aarch64-unknown-linux-musl`. ([#577](https://github.com/heroku/libcnb.rs/pull/577))
+- `libcnb-package`: buildpack target directory now contains the target triple. Users that implicitly rely on the output directory need to adapt. The output of `cargo 
+libcnb package` will refer to the new locations. ([#580](https://github.com/heroku/libcnb.rs/pull/580))
 
 ## [0.13.0] 2023-06-21
 

libcnb-cargo/src/package/command.rs

@@ -54,7 +54,7 @@ pub(crate) fn execute(args: &PackageArgs) -> Result<()> {
             let target_dir = if contains_buildpack_binaries(&buildpack_package.path) {
                 buildpack_package.path.clone()
             } else {
-                get_buildpack_target_dir(id, &workspace_target_dir, args.release)
+                get_buildpack_target_dir(id, &workspace_target_dir, args.release, &args.target)
             };
             (id, target_dir)
         })

libcnb-cargo/tests/test.rs

@@ -11,7 +11,7 @@ use tempfile::{tempdir, TempDir};
 #[test]
 #[ignore = "integration test"]
 fn package_buildpack_in_single_buildpack_project() {
-    let packaging_test = BuildpackPackagingTest::new("single_buildpack");
+    let packaging_test = BuildpackPackagingTest::new("single_buildpack", X86_64_UNKNOWN_LINUX_MUSL);
     let output = packaging_test.run_libcnb_package();
     assert_eq!(
         output.stdout.trim(),
@@ -23,7 +23,8 @@ fn package_buildpack_in_single_buildpack_project() {
 #[test]
 #[ignore = "integration test"]
 fn package_single_meta_buildpack_in_monorepo_buildpack_project() {
-    let packaging_test = BuildpackPackagingTest::new("multiple_buildpacks");
+    let packaging_test =
+        BuildpackPackagingTest::new("multiple_buildpacks", X86_64_UNKNOWN_LINUX_MUSL);
     let output = packaging_test.run_libcnb_package_from("meta-buildpacks/meta-one");
     assert_eq!(
         output.stdout.trim(),
@@ -50,7 +51,8 @@ fn package_single_meta_buildpack_in_monorepo_buildpack_project() {
 #[test]
 #[ignore = "integration test"]
 fn package_single_buildpack_in_monorepo_buildpack_project() {
-    let packaging_test = BuildpackPackagingTest::new("multiple_buildpacks");
+    let packaging_test =
+        BuildpackPackagingTest::new("multiple_buildpacks", X86_64_UNKNOWN_LINUX_MUSL);
     let output = packaging_test.run_libcnb_package_from("buildpacks/one");
     assert_eq!(
         output.stdout.trim(),
@@ -68,7 +70,8 @@ fn package_single_buildpack_in_monorepo_buildpack_project() {
 #[test]
 #[ignore = "integration test"]
 fn package_all_buildpacks_in_monorepo_buildpack_project() {
-    let packaging_test = BuildpackPackagingTest::new("multiple_buildpacks");
+    let packaging_test =
+        BuildpackPackagingTest::new("multiple_buildpacks", X86_64_UNKNOWN_LINUX_MUSL);
     let output = packaging_test.run_libcnb_package();
     assert_eq!(
         output.stdout.trim(),
@@ -105,7 +108,8 @@ fn package_all_buildpacks_in_monorepo_buildpack_project() {
 #[test]
 #[ignore = "integration test"]
 fn package_non_libcnb_buildpack_in_meta_buildpack_project() {
-    let packaging_test = BuildpackPackagingTest::new("multiple_buildpacks");
+    let packaging_test =
+        BuildpackPackagingTest::new("multiple_buildpacks", X86_64_UNKNOWN_LINUX_MUSL);
     let output = packaging_test.run_libcnb_package_from("buildpacks/not_libcnb");
     assert_eq!(
         output.stdout.trim(),
@@ -130,7 +134,7 @@ fn package_non_libcnb_buildpack_in_meta_buildpack_project() {
 #[test]
 #[ignore = "integration test"]
 fn package_command_error_when_run_in_project_with_no_buildpacks() {
-    let packaging_test = BuildpackPackagingTest::new("no_buildpacks");
+    let packaging_test = BuildpackPackagingTest::new("no_buildpacks", X86_64_UNKNOWN_LINUX_MUSL);
     let output = packaging_test.run_libcnb_package();
     assert_ne!(output.code, Some(0));
     assert_eq!(
@@ -190,6 +194,7 @@ struct BuildpackPackagingTest {
     fixture_name: String,
     temp_dir: TempDir,
     release_build: bool,
+    target_triple: String,
 }
 
 struct TestOutput {
@@ -199,7 +204,7 @@ struct TestOutput {
 }
 
 impl BuildpackPackagingTest {
-    fn new(fixture_name: &str) -> Self {
+    fn new(fixture_name: &str, target_triple: &str) -> Self {
         let source_directory = env::current_dir()
             .unwrap()
             .join("fixtures")
@@ -211,6 +216,7 @@ impl BuildpackPackagingTest {
             fixture_name: fixture_name.to_string(),
             temp_dir: target_directory,
             release_build: true,
+            target_triple: String::from(target_triple),
         }
     }
 
@@ -235,6 +241,7 @@ impl BuildpackPackagingTest {
             &buildpack_id,
             &self.dir().join("target"),
             self.release_build,
+            &self.target_triple,
         )
     }
 
@@ -296,3 +303,5 @@ impl BuildpackPackagingTest {
         }
     }
 }
+
+const X86_64_UNKNOWN_LINUX_MUSL: &str = "x86_64-unknown-linux-musl";

libcnb-package/src/lib.rs

@@ -259,9 +259,11 @@ pub fn get_buildpack_target_dir(
     buildpack_id: &BuildpackId,
     target_dir: &Path,
     is_release: bool,
+    target_triple: &str,
 ) -> PathBuf {
     target_dir
         .join("buildpack")
+        .join(target_triple)
         .join(if is_release { "release" } else { "debug" })
         .join(default_buildpack_directory_name(buildpack_id))
 }
@@ -276,13 +278,19 @@ mod tests {
     fn test_get_buildpack_target_dir() {
         let buildpack_id = buildpack_id!("some-org/with-buildpack");
         let target_dir = PathBuf::from("/target");
+        let target_triple = "x86_64-unknown-linux-musl";
+
         assert_eq!(
-            get_buildpack_target_dir(&buildpack_id, &target_dir, false),
-            PathBuf::from("/target/buildpack/debug/some-org_with-buildpack")
+            get_buildpack_target_dir(&buildpack_id, &target_dir, false, target_triple),
+            PathBuf::from(
+                "/target/buildpack/x86_64-unknown-linux-musl/debug/some-org_with-buildpack"
+            )
         );
         assert_eq!(
-            get_buildpack_target_dir(&buildpack_id, &target_dir, true),
-            PathBuf::from("/target/buildpack/release/some-org_with-buildpack")
+            get_buildpack_target_dir(&buildpack_id, &target_dir, true, target_triple),
+            PathBuf::from(
+                "/target/buildpack/x86_64-unknown-linux-musl/release/some-org_with-buildpack"
+            )
         );
     }
 }