lint: Verify we can parse the kargs.d files

This verifies the syntax of all included `kargs.d` files. I hit
this when I did a build in an image without `/usr/lib/bootc/kargs.d`
and did a
`COPY foo.toml /usr/lib/bootc/kargs.d`
which created a regular file named `kargs.d` there.

Signed-off-by: Colin Walters <[email protected]>

Author: cgwalters

lib/src/lints.rs

@@ -2,6 +2,8 @@
 //!
 //! This module implements `bootc container lint`.
 
+use std::env::consts::ARCH;
+
 use anyhow::Result;
 use cap_std::fs::Dir;
 use cap_std_ext::cap_std;
@@ -13,7 +15,7 @@ use fn_error_context::context;
 /// if it does not exist error.
 #[context("Linting")]
 pub(crate) fn lint(root: &Dir) -> Result<()> {
-    let lints = [check_var_run, check_kernel];
+    let lints = [check_var_run, check_kernel, check_parse_kargs];
     for lint in lints {
         lint(&root)?;
     }
@@ -30,6 +32,12 @@ fn check_var_run(root: &Dir) -> Result<()> {
     Ok(())
 }
 
+/// Validate that we can parse the /usr/lib/bootc/kargs.d files.
+fn check_parse_kargs(root: &Dir) -> Result<()> {
+    let _args = crate::kargs::get_kargs_in_root(root, ARCH)?;
+    Ok(())
+}
+
 fn check_kernel(root: &Dir) -> Result<()> {
     let result = ostree_ext::bootabletree::find_kernel_dir_fs(&root)?;
     tracing::debug!("Found kernel: {:?}", result);
@@ -70,3 +78,13 @@ fn test_kernel_lint() -> Result<()> {
     check_kernel(root).unwrap();
     Ok(())
 }
+
+#[test]
+fn test_kargs() -> Result<()> {
+    let root = &fixture()?;
+    check_parse_kargs(root).unwrap();
+    root.create_dir_all("usr/lib/bootc")?;
+    root.write("usr/lib/bootc/kargs.d", "not a directory")?;
+    assert!(check_parse_kargs(root).is_err());
+    Ok(())
+}