Fix typos, comments and other minor inconsistencies (#561)

Found/fixed via a Claude code review pass.

Author: edmorley

CONTRIBUTING.md

@@ -9,14 +9,14 @@ always, thanks for contributing.
 
 The intent and goal of open sourcing this project is to increase the contributor
 and user base. However, only Salesforce employees will be given `admin` rights
-and will be the final arbitrars of what contributions are accepted or not.
+and will be the final arbiters of what contributions are accepted or not.
 
 ## Getting started
 
 Please feel free to join the
 [Heroku Cloud Native Buildpacks discussions][discussions].
 You may also wish to take a look at
-[Heroku's product roadmap][roadmap] to see where are headed.
+[Heroku's product roadmap][roadmap] to see where we are headed.
 
 ## Ideas and Feedback
 
@@ -37,7 +37,7 @@ Fixes, improvements, and patches all happen via [GitHub Pull Requests on this
 repository][pulls]. If you'd like to
 improve the tests, you want to make the documentation clearer, you have an
 alternative implementation of something that may have advantages over the way
-its currently done, or you have any other change, we would be happy to hear
+it's currently done, or you have any other change, we would be happy to hear
 about it. For trivial changes, send a pull request. For non-trivial changes,
 consider [opening an issue](#issues-feature-requests-and-bug-reports) to
 discuss it first instead.

src/layers/pip_cache.rs

@@ -50,8 +50,8 @@ pub(crate) fn prepare_pip_cache(
             match cause {
                 EmptyLayerCause::InvalidMetadataAction { .. }
                 | EmptyLayerCause::RestoredLayerAction { .. } => {
-                    // We don't go into more details as to why the cache has been discarded, since
-                    // the reasons will be the same as those logged during the earlier Python layer.
+                    // We don't go into more details as to why the cache has been discarded, since the reasons
+                    // will overlap with those already logged during the earlier Python and pip layers.
                     log_info("Discarding cached pip download/wheel cache");
                 }
                 EmptyLayerCause::NewlyCreated => {}

src/layers/python.rs

@@ -85,7 +85,7 @@ pub(crate) fn install_python(
                     // S3 bucket (eg files removed, or bucket made private). To try and tell the two
                     // cases apart, we check whether the requested version included a patch component.
                     // If it did, then it's most likely user error, but if it didn't, then the patch
-                    // version is the one we resolved, and so know it should be valid.
+                    // version is the one we resolved, and so we know it should be valid.
                     //
                     // We have to check for 403s too, since S3 will return a 403 instead of a 404 for
                     // missing files, if the S3 bucket does not have public list permissions enabled.
@@ -107,7 +107,7 @@ pub(crate) fn install_python(
     }
 
     let mut layer_env = generate_layer_env(&layer_path, python_version);
-    layer.write_env(layer_env)?;
+    layer.write_env(&layer_env)?;
     // Required to pick up the automatic env vars such as PATH. See: https://github.com/heroku/libcnb.rs/issues/842
     layer_env = layer.read_env()?;
     env.clone_from(&layer_env.apply(Scope::Build, env));

src/layers/uv_cache.rs

@@ -10,7 +10,7 @@ use libcnb::layer_env::{LayerEnv, ModificationBehavior, Scope};
 // We don't need to persist uv's cache between builds, since we cache site-packages instead.
 // However, we must make uv write its cache into the same filesystem mount as the venv layer,
 // otherwise uv can't use hardlinks when installing and will fall back to slower file copies.
-// The easiest way to do this is via a temporary `cache=false`, `launch=false` layer.
+// The easiest way to do this is via a temporary uncached, build-only layer.
 // See comments in `uv_dependencies.rs` for more details.
 pub(crate) fn prepare_uv_cache(
     context: &BuildContext<PythonBuildpack>,
@@ -24,7 +24,7 @@ pub(crate) fn prepare_uv_cache(
         },
     )?;
 
-    // https://docs.astral.sh/uv/configuration/environment/#uv_cache_dir
+    // https://docs.astral.sh/uv/reference/environment/#uv_cache_dir
     let layer_env = LayerEnv::new().chainable_insert(
         Scope::Build,
         ModificationBehavior::Override,

src/layers/uv_dependencies.rs

@@ -87,7 +87,7 @@ pub(crate) fn install_dependencies(
             log_info("Creating virtual environment");
             // We use Python's `venv` module to create the virtual environment since `uv venv` creates
             // import patching hooks that we don't want: https://github.com/astral-sh/uv/issues/6426
-            // TODO: Open a PR upstream to remove those hooks or at least makes them optional.
+            // TODO: Open a PR upstream to remove those hooks or at least make them optional.
             utils::run_command_and_stream_output(
                 Command::new("python")
                     .args(["-m", "venv", "--without-pip", &layer_path.to_string_lossy()])

src/utils.rs

@@ -134,7 +134,7 @@ pub(crate) fn download_and_unpack_nested_gzip_archive(
     Ok(())
 }
 
-/// Errors that can occur when downloading and unpacking an archive using `download_and_unpack_zstd_archive`.
+/// Errors that can occur when downloading and unpacking an archive.
 #[derive(Debug)]
 pub(crate) enum DownloadUnpackArchiveError {
     Request(ureq::Error),

tests/mod.rs

@@ -25,8 +25,8 @@ fn default_build_config(fixture_path: impl AsRef<Path>) -> BuildConfig {
     let builder = builder();
     let mut config = BuildConfig::new(&builder, fixture_path);
 
-    // TODO: Once Pack build supports `--platform` and libcnb-test adjusted accordingly, change this
-    // to allow configuring the target arch independently of the builder name (eg via env var).
+    // TODO: Once Pack build supports `--platform` and libcnb-test is adjusted accordingly, change
+    // this to allow configuring the target arch independently of the builder name (eg via env var).
     let target_triple = match builder.as_str() {
         // Compile the buildpack for ARM64 iff the builder supports multi-arch and the host is ARM64.
         "heroku/builder:24" | "heroku/builder:26" if cfg!(target_arch = "aarch64") => {