Trait CommandRunner 

pub trait CommandRunner {
    // Required method
    fn run(&self, program: &str, args: &[&str]) -> Result<String, CommandError>;
}

What: Abstract command execution interface used for spawning helper binaries such as pacman.

Inputs:

• program: Executable name to run (for example, "pacman").
• args: Slice of positional arguments passed to the executable.

Output:

• Ok(String) containing UTF-8 stdout on success.
• Err(CommandError) when the invocation fails or stdout is not valid UTF-8.

Errors

• Returns Err(CommandError::Io) when command spawning or execution fails
• Returns Err(CommandError::Utf8) when stdout cannot be decoded as UTF-8
• Returns Err(CommandError::Failed) when the command exits with a non-zero status

Details:

• Implementations may stub command results to enable deterministic unit testing.
• Production code relies on SystemCommandRunner.

Required Methods

fn run(&self, program: &str, args: &[&str]) -> Result<String, CommandError>

Errors

• Returns Err(CommandError::Io) when command spawning or execution fails
• Returns Err(CommandError::Utf8) when stdout cannot be decoded as UTF-8
• Returns Err(CommandError::Failed) when the command exits with a non-zero status

Implementors

impl CommandRunner for SystemCommandRunner