monochromatic-git-policy-cli 0.5.16

//! Controls for the startup step of a command.

use super::*;
use crate::test_support::{fixture, git, git_context, remove};

/// A canonical transaction name an earlier release gave its commit directories.
const TRANSACTION: &str = "0b6c2c1e-6f5b-4d0e-9a55-3f5d8e2f6a10";

/// The identity of the main worktree of the repository at `root`.
fn identity(root: &Path) -> WorktreeIdentity {
    return WorktreeIdentity::MainWorktree {
        common_dir: root.join(".git"),
        git_dir: root.join(".git"),
        worktree_root: root.to_path_buf(),
    };
}

/// A repository with nothing left by an earlier release goes on, and so does a command outside a worktree.
#[test]
fn a_clean_repository_and_a_place_outside_a_worktree_go_on() {
    let root: PathBuf = fixture("startup-gate-clean");
    git(&root, &["init", "--quiet"]);
    assert_eq!(recover_for_command(&git_context(), &identity(root.as_path())), Gate::Clear);
    assert_eq!(recover_for_command(&git_context(), &WorktreeIdentity::OutsideWorktree), Gate::Clear);
    remove(root.as_path());
}

/// The single-journal directory of the previous executable stops the command with the way to recover it, and nothing is touched.
#[test]
fn the_previous_executables_journal_directory_stops_the_command() {
    let root: PathBuf = fixture("startup-gate-legacy");
    git(&root, &["init", "--quiet"]);
    let legacy: PathBuf = root.join(".git").join(LEGACY_JOURNAL_DIRECTORY_NAME);
    std::fs::create_dir(&legacy).expect("legacy directory");
    assert_eq!(
        recover_for_command(&git_context(), &identity(root.as_path())),
        Gate::Stop(legacy_notice(legacy.as_path()))
    );
    assert!(legacy.is_dir(), "nothing was removed");
    remove(root.as_path());
}

/// A registry that holds only locks and staging names has nothing to look at; a transaction directory in it is named.
#[test]
fn a_registry_note_appears_only_for_a_transaction_directory() {
    let root: PathBuf = fixture("startup-gate-registry");
    assert_eq!(registry_note(root.join("absent").as_path()), None, "no registry, no note");
    let registry: PathBuf = root.join(REGISTRY_DIRECTORY_NAME);
    std::fs::create_dir_all(registry.join("landing.lock")).expect("lock directory");
    std::fs::create_dir_all(registry.join(format!("{TRANSACTION}.pending"))).expect("staging directory");
    assert_eq!(registry_note(registry.as_path()), None, "locks and staging names are not commits");
    std::fs::create_dir_all(registry.join(TRANSACTION)).expect("transaction directory");
    let note: String = registry_note(registry.as_path()).expect("a note");
    assert!(note.contains(registry.to_string_lossy().as_ref()), "{note}");
    assert!(note.contains("git status"), "the way to see whether the commit was made: {note}");
    assert!(note.contains("no longer uses that directory"), "it says the directory is unused: {note}");
    assert!(registry.join(TRANSACTION).is_dir(), "nothing was removed");
    remove(root.as_path());
}

/// The command the note ends with, which is everything after its last colon-and-space marker, without the line break.
fn removal_command(note: &str) -> String {
    let (_, command) = note.rsplit_once("directory with: ").expect("the note ends with the removal command");
    return command.trim_end_matches('\n').to_string();
}

/// Running a note's removal command in a shell removes the registry it names and nothing beside it, whatever the name holds.
#[test]
fn the_removal_command_in_the_note_removes_exactly_the_registry() {
    let root: PathBuf = fixture("startup-gate-removal");
    for name in ["plain", "with space", "it's quoted", "$HOME `date` \"x\" \\ ; echo", "line\nbreak", "-dash"] {
        let git_dir: PathBuf = root.join(name);
        let registry: PathBuf = git_dir.join(REGISTRY_DIRECTORY_NAME);
        std::fs::create_dir_all(registry.join(TRANSACTION)).expect("transaction directory");
        std::fs::write(git_dir.join("HEAD"), "ref: refs/heads/main\n").expect("a sibling file that must stay");
        let note: String = registry_note(registry.as_path()).expect("a note");
        assert!(note.starts_with("cli-git: "), "{note}");
        let command: String = removal_command(note.as_str());
        let status = std::process::Command::new("sh").arg("-c").arg(command.as_str()).status().expect("sh runs");
        assert!(status.success(), "{name:?}: {command}");
        assert!(!registry.exists(), "{name:?}: the command removed the registry: {command}");
        assert!(git_dir.join("HEAD").is_file(), "{name:?}: the command left the sibling file: {command}");
    }
    remove(root.as_path());
}

/// A registry whose name is not UTF-8 gets a command in the `$'...'` form, which bash reads back as the exact bytes.
#[cfg(unix)]
#[test]
fn the_removal_command_names_a_registry_that_is_not_utf8_by_its_bytes() {
    /// The Unix conversion from raw bytes.
    use std::os::unix::ffi::OsStringExt;
    let root: PathBuf = fixture("startup-gate-removal-bytes");
    let git_dir: PathBuf = root.join(std::ffi::OsString::from_vec(b"bytes\xff'\\\n\x01".to_vec()));
    let registry: PathBuf = git_dir.join(REGISTRY_DIRECTORY_NAME);
    std::fs::create_dir_all(registry.join(TRANSACTION)).expect("transaction directory");
    std::fs::write(git_dir.join("HEAD"), "ref: refs/heads/main\n").expect("a sibling file that must stay");
    let note: String = registry_note(registry.as_path()).expect("a note");
    let command: String = removal_command(note.as_str());
    assert!(command.contains("$'"), "bytes that are not UTF-8 use the ANSI-C form: {command}");
    let status = std::process::Command::new("bash").arg("-c").arg(command.as_str()).status().expect("bash runs");
    assert!(status.success(), "{command}");
    assert!(!registry.exists(), "the command removed the registry: {command}");
    assert!(git_dir.join("HEAD").is_file(), "the command left the sibling file: {command}");
    remove(root.as_path());
}

/// A word quotes text with the quote spelling a shell reads back, and leaves nothing for the shell to expand.
#[test]
fn a_shell_word_quotes_a_single_quote_and_leaves_nothing_to_expand() {
    assert_eq!(shell_word(Path::new("/a b/c")), "'/a b/c'");
    assert_eq!(shell_word(Path::new("/it's")), "'/it'\\''s'");
    assert_eq!(shell_word(Path::new("$HOME")), "'$HOME'");
}

/// A transaction directory an earlier release left does not stop the command: the note goes to standard error and the command goes on.
#[test]
fn a_registry_of_an_earlier_release_does_not_stop_the_command() {
    let root: PathBuf = fixture("startup-gate-registry-goes-on");
    git(&root, &["init", "--quiet"]);
    std::fs::create_dir_all(root.join(".git").join(REGISTRY_DIRECTORY_NAME).join(TRANSACTION)).expect("transaction directory");
    assert_eq!(recover_for_command(&git_context(), &identity(root.as_path())), Gate::Clear);
    remove(root.as_path());
}