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running_process_platform_internal/platform/
executable.rs

1//! Executable naming, search, image discovery, and materialization primitives.
2//!
3//! Callers name the *program* they want. Whether that program is a file called
4//! `runpm` or `runpm.exe`, and where a sibling install lives relative to the
5//! running image, is a host mechanic and is decided here.
6
7pub use crate::{
8    executable_file_name as file_name,
9    executable_sibling_of_current_image as sibling_of_current_image, EXECUTABLE_EXTENSION,
10};
11
12#[cfg(test)]
13mod tests {
14    use super::*;
15
16    /// The host decides the spelling; the caller never does.
17    ///
18    /// Asserted against `EXECUTABLE_EXTENSION` rather than a hard-coded
19    /// `.exe`, so the test states the contract instead of restating one host's
20    /// answer -- the shape the caller sites used to have.
21    #[test]
22    fn file_name_applies_the_host_executable_extension() {
23        let named = file_name("running-process-daemon");
24        match EXECUTABLE_EXTENSION {
25            Some(extension) => {
26                assert_eq!(named, format!("running-process-daemon.{extension}"));
27                assert!(std::path::Path::new(&named).extension().is_some());
28            }
29            None => assert_eq!(named, "running-process-daemon"),
30        }
31    }
32
33    /// The running image is always a sibling of itself, under whatever
34    /// spelling this host uses -- which is the only claim that holds on every
35    /// host without assuming what else is installed.
36    #[test]
37    fn the_running_image_is_found_beside_itself() {
38        let current = std::env::current_exe().expect("current image");
39        let bare = current
40            .file_stem()
41            .expect("image stem")
42            .to_string_lossy()
43            .into_owned();
44
45        assert_eq!(sibling_of_current_image(&bare).as_deref(), Some(&*current));
46    }
47
48    /// A program that is not installed beside us is reported as absent rather
49    /// than as a path that does not exist.
50    #[test]
51    fn an_absent_sibling_is_none_not_a_missing_path() {
52        assert!(sibling_of_current_image("rp-no-such-sibling-program").is_none());
53    }
54}