zsh/extensions/

intercepts.rs

//! Command intercept / advice machinery — extension; no zsh C counterpart.
#[allow(unused_imports)]
use crate::ported::vm_helper::ShellExecutor;
#[allow(unused_imports)]
use std::collections::HashMap;

/// AOP advice type — before, after, or around.
#[derive(Debug, Clone)]
/// Aspect-oriented advice classification.
/// zshrs-original — no C zsh counterpart. C zsh's closest
/// analog is the function-wrapper hook in Src/module.c
/// (`addwrapper()`, used by `zsh/zprof`), but per-function
/// before/after/around AOP intercepts are unique to zshrs.
pub enum AdviceKind {
    /// Run code before the command executes.
    Before,
    /// Run code after the command executes. $? and INTERCEPT_MS available.
    After,
    /// Wrap the command. Code must call `intercept_proceed` to run original.
    Around,
}

/// An intercept registration.
#[derive(Debug, Clone)]
/// One AOP intercept registered against a function pattern.
/// zshrs-original — no C counterpart.
pub struct Intercept {
    /// Pattern to match command names. Supports glob: "git *", "_*", "*".
    pub pattern: String,
    /// What kind of advice.
    pub kind: AdviceKind,
    /// Shell code to execute as advice.
    pub code: String,
    /// Unique ID for removal.
    pub id: u32,
}

/// Match an intercept pattern against a command name or full command string.
/// Supports: exact match, glob ("git *", "_*", "*"), or "all".
pub(crate) fn intercept_matches(pattern: &str, cmd_name: &str, full_cmd: &str) -> bool {
    if pattern == "*" || pattern == "all" {
        return true;
    }
    if pattern == cmd_name {
        return true;
    }
    if pattern.contains('*') || pattern.contains('?') {
        if let Ok(pat) = glob::Pattern::new(pattern) {
            return pat.matches(cmd_name) || pat.matches(full_cmd);
        }
    }
    false
}

// ===========================================================
// Methods moved verbatim from src/ported/vm_helper because their
// C counterpart's source file maps 1:1 to this Rust module.
// Phase: drift
// ===========================================================

// BEGIN moved-from-exec-rs
impl crate::ported::vm_helper::ShellExecutor {
    /// Check intercepts for a command. Returns Some(result) if an around
    /// advice fully handled the command, None to proceed normally.
    pub(crate) fn run_intercepts(
        &mut self,
        cmd_name: &str,
        full_cmd: &str,
        args: &[String],
    ) -> Option<Result<i32, String>> {
        // Collect matching intercepts (clone to avoid borrow issues)
        let matching: Vec<Intercept> = self
            .intercepts
            .iter()
            .filter(|i| intercept_matches(&i.pattern, cmd_name, full_cmd))
            .cloned()
            .collect();

        if matching.is_empty() {
            return None;
        }

        // Set INTERCEPT_NAME and INTERCEPT_ARGS for advice code
        self.set_scalar("INTERCEPT_NAME".to_string(), cmd_name.to_string());
        self.set_scalar("INTERCEPT_ARGS".to_string(), args.join(" "));
        self.set_scalar("INTERCEPT_CMD".to_string(), full_cmd.to_string());

        // Run before advice
        for advice in matching
            .iter()
            .filter(|i| matches!(i.kind, AdviceKind::Before))
        {
            let _ = self.execute_advice(&advice.code);
        }

        // Check for around advice — first match wins
        let around = matching
            .iter()
            .find(|i| matches!(i.kind, AdviceKind::Around));

        let t0 = std::time::Instant::now();

        let result = if let Some(advice) = around {
            // Around advice: set INTERCEPT_PROCEED flag, run advice code.
            // If advice calls `intercept_proceed`, the original command runs.
            self.set_scalar("__intercept_proceed".to_string(), "0".to_string());
            let advice_result = self.execute_advice(&advice.code);

            // Check if intercept_proceed was called
            let proceeded = self
                .scalar("__intercept_proceed")
                .map(|v| v == "1")
                .unwrap_or(false);

            if proceeded {
                // The original command was already executed inside the advice
                advice_result
            } else {
                // Advice didn't call proceed — command was suppressed
                advice_result
            }
        } else {
            // No around advice — run the original command.
            // We return None to let the normal dispatch continue.
            // But we still need after advice to fire, so we can't return None here
            // if there are after advices. Run the command ourselves.
            let has_after = matching.iter().any(|i| matches!(i.kind, AdviceKind::After));
            if !has_after {
                // Only before advice, no after — let normal dispatch continue
                return None;
            }

            // Has after advice — we must run the command and then run after advice
            self.run_original_command(cmd_name, args)
        };

        let elapsed = t0.elapsed();

        // Set timing variable for after advice
        let ms = elapsed.as_secs_f64() * 1000.0;
        self.set_scalar("INTERCEPT_MS".to_string(), format!("{:.3}", ms));
        self.set_scalar("INTERCEPT_US".to_string(), format!("{:.0}", ms * 1000.0));

        // Run after advice
        for advice in matching
            .iter()
            .filter(|i| matches!(i.kind, AdviceKind::After))
        {
            let _ = self.execute_advice(&advice.code);
        }

        // Clean up
        self.unset_scalar("INTERCEPT_NAME");
        self.unset_scalar("INTERCEPT_ARGS");
        self.unset_scalar("INTERCEPT_CMD");
        self.unset_scalar("INTERCEPT_MS");
        self.unset_scalar("INTERCEPT_US");
        self.unset_scalar("__intercept_proceed");

        Some(result)
    }
    /// Execute the original command (used by around/after intercept dispatch).
    /// Execute advice code — dispatches @ prefix to stryke (fat binary),
    /// everything else to the shell parser. No fork. Machine code speed.
    pub(crate) fn execute_advice(&mut self, code: &str) -> Result<i32, String> {
        let code = code.trim();
        if code.starts_with('@') {
            let stryke_code = code.trim_start_matches('@').trim();
            if let Some(status) = crate::try_stryke_dispatch(stryke_code) {
                self.set_last_status(status);
                return Ok(status);
            }
            // No stryke handler (thin binary) — fall through to shell
        }
        self.execute_script(code)
    }
    pub(crate) fn run_original_command(
        &mut self,
        cmd_name: &str,
        args: &[String],
    ) -> Result<i32, String> {
        // Function dispatch via the compiled pipeline (functions_compiled
        // first, falls back to legacy AST recompile if needed).
        if let Some(status) = self.dispatch_function_call(cmd_name, args) {
            return Ok(status);
        }
        // External command
        self.execute_external(cmd_name, args, &[])
    }
}
// END moved-from-exec-rs

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn star_matches_anything() {
        assert!(intercept_matches("*", "anything", "anything --here"));
        assert!(intercept_matches("*", "", ""));
    }

    #[test]
    fn all_matches_anything() {
        assert!(intercept_matches("all", "ls", "ls -la"));
        assert!(intercept_matches("all", "git", "git status"));
    }

    #[test]
    fn exact_match_on_cmd_name() {
        assert!(intercept_matches("git", "git", "git push"));
        assert!(intercept_matches("ls", "ls", "ls -la"));
    }

    #[test]
    fn exact_pattern_does_not_match_different_name() {
        assert!(!intercept_matches("git", "svn", "svn diff"));
        assert!(!intercept_matches("ls", "lsof", "lsof -p 1"));
    }

    #[test]
    fn glob_star_matches_prefix() {
        // "git *" should match the full command line like "git push origin".
        assert!(intercept_matches("git *", "git", "git push origin"));
    }

    #[test]
    fn glob_star_underscore_prefix_matches_completion_funcs() {
        // "_*" is the canonical zsh pattern for completion functions.
        assert!(intercept_matches("_*", "_files", "_files"));
        assert!(intercept_matches("_*", "_describe", "_describe"));
    }

    #[test]
    fn glob_star_does_not_match_non_prefix() {
        assert!(!intercept_matches("_*", "files", "files"));
    }

    #[test]
    fn question_mark_glob_matches_single_char() {
        assert!(intercept_matches("l?", "ls", "ls"));
        assert!(!intercept_matches("l?", "lsof", "lsof"));
    }

    #[test]
    fn unmatched_pattern_without_glob_chars_returns_false() {
        assert!(!intercept_matches("nope", "git", "git push"));
    }

    #[test]
    fn invalid_glob_pattern_returns_false() {
        // `[` with no closing bracket is invalid; should not panic and not match.
        // Pattern with `[` triggers neither the `*` shortcut nor exact match,
        // but it also contains no `*` or `?`, so we never reach glob parsing.
        assert!(!intercept_matches("[invalid", "git", "git push"));
    }

    #[test]
    fn empty_pattern_does_not_match_non_empty_cmd() {
        assert!(!intercept_matches("", "ls", "ls -la"));
    }

    #[test]
    fn empty_pattern_matches_empty_cmd_exactly() {
        // Falls through to the `pattern == cmd_name` check.
        assert!(intercept_matches("", "", ""));
    }

    #[test]
    fn advice_kind_variants_round_trip_clone() {
        let b = AdviceKind::Before;
        let a = AdviceKind::After;
        let r = AdviceKind::Around;
        assert!(matches!(b.clone(), AdviceKind::Before));
        assert!(matches!(a.clone(), AdviceKind::After));
        assert!(matches!(r.clone(), AdviceKind::Around));
    }

    #[test]
    fn intercept_struct_clone_preserves_fields() {
        let i = Intercept {
            pattern: "git *".into(),
            kind: AdviceKind::Before,
            code: "echo before".into(),
            id: 42,
        };
        let c = i.clone();
        assert_eq!(c.pattern, "git *");
        assert!(matches!(c.kind, AdviceKind::Before));
        assert_eq!(c.code, "echo before");
        assert_eq!(c.id, 42);
    }
}