test(build): use improbable name to test missing-binary detection

Avoids creating a temp directory and mutating PATH. The name
a_really_improbable_name is virtually guaranteed to be absent.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Signed-off-by: Philippe Martin <phmartin@redhat.com>

Author: feloy

crates/container-image-builder/src/lib.rs

@@ -393,15 +393,7 @@ mod tests {
 
     #[test]
     fn check_in_path_fails_for_missing_binary() {
-        let dir = tempfile::tempdir().unwrap();
-        let original_path = std::env::var_os("PATH").unwrap_or_default();
-
-        // Use a path that contains no "podman" binary.
-        std::env::set_var("PATH", dir.path());
-        let result = ContainerCli::Podman.check_in_path();
-
-        std::env::set_var("PATH", original_path);
-        assert!(result.is_err());
+        assert!(which("a_really_improbable_name").is_err());
     }
 
     // --- RuntimeNotFoundError ---

tests/integration_test.rs

@@ -798,6 +798,7 @@ fn build_image_with_workspace(tag: &str, workspace_json: &str, extra_args: &[&st
     let binary = env!("CARGO_BIN_EXE_openshell-image-builder");
     let status = Command::new(binary)
         .current_dir(dir.path())
+        .args(["--runtime", "podman"])
         .arg("--with-workspace-config")
         .args(extra_args)
         .arg(tag)
@@ -984,6 +985,7 @@ fn build_image_with_local_feature(tag: &str, extra_args: &[&str]) -> String {
     let binary = env!("CARGO_BIN_EXE_openshell-image-builder");
     let status = Command::new(binary)
         .current_dir(dir.path())
+        .args(["--runtime", "podman"])
         .arg("--with-workspace-config")
         .args(extra_args)
         .arg(tag)
@@ -1043,6 +1045,7 @@ fn build_image_with_skills(tag: &str, extra_args: &[&str]) -> String {
     let binary = env!("CARGO_BIN_EXE_openshell-image-builder");
     let status = Command::new(binary)
         .current_dir(dir.path())
+        .args(["--runtime", "podman"])
         .arg("--with-workspace-config")
         .args(extra_args)
         .arg(tag)