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task_mcp/just/
mod.rs

1pub mod model;
2
3use std::collections::{HashMap, VecDeque};
4use std::path::{Path, PathBuf};
5use std::sync::Mutex;
6use std::time::{Duration, SystemTime, UNIX_EPOCH};
7
8use tokio::process::Command;
9use uuid::Uuid;
10
11use crate::config::TaskMode;
12use crate::just::model::{
13    JustDump, JustRecipe, Recipe, RecipeSource, TaskError, TaskExecution, TaskExecutionSummary,
14};
15
16// =============================================================================
17// Error
18// =============================================================================
19
20#[derive(Debug, thiserror::Error)]
21pub enum JustError {
22    #[error("just command not found: {0}")]
23    NotFound(String),
24    #[error("just command failed (exit {code}): {stderr}")]
25    CommandFailed { code: i32, stderr: String },
26    #[error("failed to parse just dump json: {0}")]
27    ParseError(#[from] serde_json::Error),
28    #[error("I/O error while reading justfile: {0}")]
29    Io(#[from] std::io::Error),
30}
31
32// =============================================================================
33// Public API
34// =============================================================================
35
36/// Discover recipes from the justfile at `justfile_path`.
37///
38/// Filtering behaviour depends on `mode`:
39/// - `TaskMode::AgentOnly`: only recipes marked agent-safe are returned.
40/// - `TaskMode::All`: all non-private recipes are returned.
41///
42/// Agent-safe detection is based entirely on the JSON output of `just --dump`:
43/// 1. `[group('allow-agent')]` attribute (preferred, deterministic), or
44/// 2. `[allow-agent]` marker inside the recipe's doc comment (legacy fallback).
45pub async fn list_recipes(
46    justfile_path: &Path,
47    mode: &TaskMode,
48    workdir: Option<&Path>,
49) -> Result<Vec<Recipe>, JustError> {
50    list_recipes_with_source(justfile_path, mode, workdir, RecipeSource::Project).await
51}
52
53/// Discover and merge recipes from a project justfile and an optional global justfile.
54///
55/// Merge semantics:
56/// - Both sides are filtered by `mode` independently.
57/// - Project recipes have `source = Project`; global recipes have `source = Global`.
58/// - On name collision, the project recipe wins (global is hidden).
59/// - Result order: project recipes (alphabetical) followed by global-only recipes (alphabetical).
60///
61/// When `global_path` is `None`, this is equivalent to `list_recipes`.
62pub async fn list_recipes_merged(
63    project_path: &Path,
64    global_path: Option<&Path>,
65    mode: &TaskMode,
66    project_workdir: Option<&Path>,
67) -> Result<Vec<Recipe>, JustError> {
68    // Collect project recipes, tagging them as Project source.
69    // If the project justfile does not exist (e.g. new project with global-only setup),
70    // treat it as an empty list rather than propagating a "file not found" error.
71    let project_recipes = if tokio::fs::metadata(project_path).await.is_ok() {
72        list_recipes_with_source(project_path, mode, project_workdir, RecipeSource::Project).await?
73    } else {
74        Vec::new()
75    };
76
77    let global_path = match global_path {
78        Some(p) => p,
79        None => return Ok(project_recipes),
80    };
81
82    // Collect global recipes, tagging them as Global source.
83    // Use project_workdir as workdir so global recipes run in project context.
84    let global_recipes =
85        list_recipes_with_source(global_path, mode, project_workdir, RecipeSource::Global).await?;
86
87    // Build name set from project recipes for override detection.
88    let project_names: std::collections::HashSet<&str> =
89        project_recipes.iter().map(|r| r.name.as_str()).collect();
90
91    // Global-only recipes (not overridden by project).
92    let global_only: Vec<Recipe> = global_recipes
93        .into_iter()
94        .filter(|r| !project_names.contains(r.name.as_str()))
95        .collect();
96
97    // Result: project first, then global-only.
98    let mut merged = project_recipes;
99    merged.extend(global_only);
100    Ok(merged)
101}
102
103/// Internal helper: like `list_recipes` but tags each recipe with `source`.
104async fn list_recipes_with_source(
105    justfile_path: &Path,
106    mode: &TaskMode,
107    workdir: Option<&Path>,
108    source: RecipeSource,
109) -> Result<Vec<Recipe>, JustError> {
110    let dump = dump_json(justfile_path, workdir).await?;
111
112    let mut recipes: Vec<Recipe> = dump
113        .recipes
114        .into_values()
115        .filter(|r| !r.private)
116        .map(|raw| {
117            let allow_agent = is_allow_agent(&raw);
118            Recipe::from_just_recipe_with_source(raw, allow_agent, source)
119        })
120        .collect();
121
122    recipes.sort_by(|a, b| a.name.cmp(&b.name));
123
124    match mode {
125        TaskMode::AgentOnly => Ok(recipes.into_iter().filter(|r| r.allow_agent).collect()),
126        TaskMode::All => Ok(recipes),
127    }
128}
129
130// =============================================================================
131// Internal helpers
132// =============================================================================
133
134/// Run `just --dump --dump-format json --unstable` and return parsed output.
135async fn dump_json(justfile_path: &Path, workdir: Option<&Path>) -> Result<JustDump, JustError> {
136    let mut cmd = Command::new("just");
137    cmd.arg("--justfile")
138        .arg(justfile_path)
139        .arg("--dump")
140        .arg("--dump-format")
141        .arg("json")
142        .arg("--unstable");
143    if let Some(dir) = workdir {
144        cmd.current_dir(dir);
145    }
146    let output = cmd
147        .output()
148        .await
149        .map_err(|e| JustError::NotFound(e.to_string()))?;
150
151    if !output.status.success() {
152        let code = output.status.code().unwrap_or(-1);
153        let stderr = String::from_utf8_lossy(&output.stderr).into_owned();
154        return Err(JustError::CommandFailed { code, stderr });
155    }
156
157    let json_str = String::from_utf8_lossy(&output.stdout);
158    let dump: JustDump = serde_json::from_str(&json_str)?;
159    Ok(dump)
160}
161
162/// Pattern A: check if the recipe has a `[group('allow-agent')]` attribute.
163fn has_allow_agent_group_attribute(recipe: &JustRecipe) -> bool {
164    recipe
165        .attributes
166        .iter()
167        .any(|a| a.group() == Some("allow-agent"))
168}
169
170/// Pattern B: legacy `# [allow-agent]` marker embedded in the recipe doc comment.
171///
172/// `just --dump` preserves the comment line immediately above a recipe as its
173/// `doc` field. When users tag recipes with a `# [allow-agent]` line, that text
174/// shows up here, so we can detect it without re-reading the source file.
175///
176/// Note: `just` only keeps the closest comment line as the doc, so combining
177/// `# [allow-agent]` with a descriptive doc comment causes one of the two to be
178/// dropped. Prefer the `[group('allow-agent')]` attribute for new recipes.
179fn has_allow_agent_doc(recipe: &JustRecipe) -> bool {
180    recipe
181        .doc
182        .as_deref()
183        .is_some_and(|d| d.split_whitespace().any(|t| t == "[allow-agent]"))
184}
185
186/// Determine if a recipe is agent-safe via group attribute or legacy doc marker.
187fn is_allow_agent(recipe: &JustRecipe) -> bool {
188    has_allow_agent_group_attribute(recipe) || has_allow_agent_doc(recipe)
189}
190
191/// Resolve justfile path from an optional override, workdir, or the current directory.
192pub fn resolve_justfile_path(override_path: Option<&str>, workdir: Option<&Path>) -> PathBuf {
193    match override_path {
194        Some(p) => PathBuf::from(p),
195        None => match workdir {
196            Some(dir) => dir.join("justfile"),
197            None => PathBuf::from("justfile"),
198        },
199    }
200}
201
202// =============================================================================
203// Output truncation
204// =============================================================================
205
206const MAX_OUTPUT_BYTES: usize = 100 * 1024; // 100 KB
207const HEAD_BYTES: usize = 50 * 1024; // 50 KB
208const TAIL_BYTES: usize = 50 * 1024; // 50 KB
209
210/// Truncate output to at most `MAX_OUTPUT_BYTES`.
211///
212/// If truncation is necessary the result contains:
213/// `{head}\n...[truncated {n} bytes]...\n{tail}`
214///
215/// UTF-8 multi-byte boundaries are respected — the slice points are adjusted
216/// so that we never split a multi-byte character.
217pub fn truncate_output(output: &str) -> (String, bool) {
218    if output.len() <= MAX_OUTPUT_BYTES {
219        return (output.to_string(), false);
220    }
221
222    // Find safe byte boundary for the head (≤ HEAD_BYTES)
223    let head_end = safe_byte_boundary(output, HEAD_BYTES);
224    // Find safe byte boundary for the tail (last TAIL_BYTES)
225    let tail_start_raw = output.len().saturating_sub(TAIL_BYTES);
226    let tail_start = safe_tail_start(output, tail_start_raw);
227
228    let head = &output[..head_end];
229    let tail = &output[tail_start..];
230    let truncated_bytes = output.len() - head_end - (output.len() - tail_start);
231
232    (
233        format!("{head}\n...[truncated {truncated_bytes} bytes]...\n{tail}"),
234        true,
235    )
236}
237
238/// Find the largest byte index `<= limit` that lies on a UTF-8 character boundary.
239fn safe_byte_boundary(s: &str, limit: usize) -> usize {
240    if limit >= s.len() {
241        return s.len();
242    }
243    // Walk backwards from `limit` until we hit a valid char boundary
244    let mut idx = limit;
245    while idx > 0 && !s.is_char_boundary(idx) {
246        idx -= 1;
247    }
248    idx
249}
250
251/// Find the smallest byte index `>= hint` that lies on a UTF-8 character boundary.
252fn safe_tail_start(s: &str, hint: usize) -> usize {
253    if hint >= s.len() {
254        return s.len();
255    }
256    let mut idx = hint;
257    while idx < s.len() && !s.is_char_boundary(idx) {
258        idx += 1;
259    }
260    idx
261}
262
263// =============================================================================
264// Argument validation
265// =============================================================================
266
267/// Reject argument values that contain shell meta-characters.
268///
269/// `tokio::process::Command` bypasses the shell, but `just` itself invokes a
270/// shell interpreter for recipe bodies.  Validating inputs here prevents
271/// injection attacks in case a recipe passes an argument through to the shell.
272pub fn validate_arg_value(value: &str) -> Result<(), TaskError> {
273    const DANGEROUS: &[&str] = &[";", "|", "&&", "||", "`", "$(", "${", "\n", "\r"];
274    for pattern in DANGEROUS {
275        if value.contains(pattern) {
276            return Err(TaskError::DangerousArgument(value.to_string()));
277        }
278    }
279    Ok(())
280}
281
282// =============================================================================
283// Recipe execution
284// =============================================================================
285
286/// Execute a recipe by name, passing `args` as positional parameters.
287///
288/// Steps:
289/// 1. Confirm the recipe exists in `list_recipes(justfile_path, mode)`.
290/// 2. Validate each argument value for dangerous characters.
291/// 3. Run `just --justfile {path} {recipe_name} {arg_values...}` with a
292///    timeout.
293/// 4. Capture stdout/stderr and apply truncation.
294/// 5. Return a `TaskExecution` record.
295pub async fn execute_recipe(
296    recipe_name: &str,
297    args: &HashMap<String, String>,
298    justfile_path: &Path,
299    timeout: Duration,
300    mode: &TaskMode,
301    workdir: Option<&Path>,
302) -> Result<TaskExecution, TaskError> {
303    // 1. Whitelist check
304    let recipes = list_recipes(justfile_path, mode, workdir).await?;
305    let recipe = recipes
306        .iter()
307        .find(|r| r.name == recipe_name)
308        .ok_or_else(|| TaskError::RecipeNotFound(recipe_name.to_string()))?;
309
310    // 2. Argument validation
311    for value in args.values() {
312        validate_arg_value(value)?;
313    }
314
315    execute_with_justfile(recipe, args, justfile_path, workdir, timeout).await
316}
317
318/// Execute a recipe resolved from a merged recipe list (project + optional global).
319///
320/// Lookup order: project first, then global. When the recipe is found in the global
321/// justfile, `global_justfile_path` is used as `--justfile` but the cwd remains
322/// `project_workdir` so that recipes that write to `./` target the project directory.
323pub async fn execute_recipe_merged(
324    recipe_name: &str,
325    args: &HashMap<String, String>,
326    project_justfile_path: &Path,
327    global_justfile_path: Option<&Path>,
328    timeout: Duration,
329    mode: &TaskMode,
330    project_workdir: Option<&Path>,
331) -> Result<TaskExecution, TaskError> {
332    // Build merged recipe list to find the target recipe and its source.
333    let recipes = list_recipes_merged(
334        project_justfile_path,
335        global_justfile_path,
336        mode,
337        project_workdir,
338    )
339    .await?;
340
341    let recipe = recipes
342        .iter()
343        .find(|r| r.name == recipe_name)
344        .ok_or_else(|| TaskError::RecipeNotFound(recipe_name.to_string()))?;
345
346    // Validate arguments.
347    for value in args.values() {
348        validate_arg_value(value)?;
349    }
350
351    // Determine which justfile to invoke based on recipe source.
352    let effective_justfile = match recipe.source {
353        RecipeSource::Global => global_justfile_path
354            .ok_or_else(|| TaskError::RecipeNotFound(recipe_name.to_string()))?,
355        RecipeSource::Project => project_justfile_path,
356    };
357
358    execute_with_justfile(recipe, args, effective_justfile, project_workdir, timeout).await
359}
360
361/// Internal helper that constructs and runs a `just` command for the given recipe.
362///
363/// Handles argument ordering, timeout, output capture/truncation, and
364/// `TaskExecution` assembly.  Both `execute_recipe` and `execute_recipe_merged`
365/// delegate here after performing their recipe-lookup and validation steps.
366async fn execute_with_justfile(
367    recipe: &Recipe,
368    args: &HashMap<String, String>,
369    effective_justfile: &Path,
370    project_workdir: Option<&Path>,
371    timeout: Duration,
372) -> Result<TaskExecution, TaskError> {
373    // Build positional argument list in parameter definition order.
374    let positional: Vec<&str> = recipe
375        .parameters
376        .iter()
377        .filter_map(|p| args.get(&p.name).map(|v| v.as_str()))
378        .collect();
379
380    let started_at = SystemTime::now()
381        .duration_since(UNIX_EPOCH)
382        .unwrap_or_default()
383        .as_secs();
384    let start_instant = std::time::Instant::now();
385
386    let mut cmd = Command::new("just");
387    cmd.arg("--justfile").arg(effective_justfile);
388    if let Some(dir) = project_workdir {
389        cmd.arg("--working-directory").arg(dir);
390        cmd.current_dir(dir);
391    }
392    cmd.arg(&recipe.name);
393    for arg in &positional {
394        cmd.arg(arg);
395    }
396
397    let run_result = tokio::time::timeout(timeout, cmd.output()).await;
398    let duration_ms = start_instant.elapsed().as_millis() as u64;
399
400    let output = match run_result {
401        Err(_) => return Err(TaskError::Timeout),
402        Ok(Err(io_err)) => return Err(TaskError::Io(io_err)),
403        Ok(Ok(out)) => out,
404    };
405
406    let exit_code = output.status.code();
407    let raw_stdout = String::from_utf8_lossy(&output.stdout).into_owned();
408    let raw_stderr = String::from_utf8_lossy(&output.stderr).into_owned();
409    let (stdout, stdout_truncated) = truncate_output(&raw_stdout);
410    let (stderr, stderr_truncated) = truncate_output(&raw_stderr);
411    let truncated = stdout_truncated || stderr_truncated;
412
413    Ok(TaskExecution {
414        id: Uuid::new_v4().to_string(),
415        task_name: recipe.name.clone(),
416        args: args.clone(),
417        exit_code,
418        stdout,
419        stderr,
420        started_at,
421        duration_ms,
422        truncated,
423    })
424}
425
426// =============================================================================
427// Task log store
428// =============================================================================
429
430/// In-memory ring buffer of recent task executions.
431///
432/// `Arc<TaskLogStore>` is `Clone` because `Arc<T>` implements `Clone` for any
433/// `T: ?Sized`.  `TaskLogStore` itself does not need to implement `Clone`.
434pub struct TaskLogStore {
435    logs: Mutex<VecDeque<TaskExecution>>,
436    max_entries: usize,
437}
438
439impl TaskLogStore {
440    pub fn new(max_entries: usize) -> Self {
441        Self {
442            logs: Mutex::new(VecDeque::new()),
443            max_entries,
444        }
445    }
446
447    /// Append an execution record, evicting the oldest entry when full.
448    pub fn push(&self, execution: TaskExecution) {
449        let mut guard = self.logs.lock().expect("log store lock poisoned");
450        if guard.len() >= self.max_entries {
451            guard.pop_front();
452        }
453        guard.push_back(execution);
454    }
455
456    /// Look up a specific execution by ID.  Returns a clone.
457    pub fn get(&self, id: &str) -> Option<TaskExecution> {
458        let guard = self.logs.lock().expect("log store lock poisoned");
459        guard.iter().find(|e| e.id == id).cloned()
460    }
461
462    /// Return summaries of the most recent `n` executions (newest first).
463    pub fn recent(&self, n: usize) -> Vec<TaskExecutionSummary> {
464        let guard = self.logs.lock().expect("log store lock poisoned");
465        guard
466            .iter()
467            .rev()
468            .take(n)
469            .map(TaskExecutionSummary::from_execution)
470            .collect()
471    }
472}
473
474#[cfg(test)]
475mod tests {
476    use super::*;
477    use crate::just::model::RecipeAttribute;
478
479    fn make_recipe(name: &str, attributes: Vec<RecipeAttribute>) -> JustRecipe {
480        make_recipe_with_doc(name, attributes, None)
481    }
482
483    fn make_recipe_with_doc(
484        name: &str,
485        attributes: Vec<RecipeAttribute>,
486        doc: Option<&str>,
487    ) -> JustRecipe {
488        crate::just::model::JustRecipe {
489            name: name.to_string(),
490            namepath: name.to_string(),
491            doc: doc.map(str::to_string),
492            attributes,
493            parameters: vec![],
494            private: false,
495            quiet: false,
496        }
497    }
498
499    #[test]
500    fn has_allow_agent_group_attribute_true() {
501        let recipe = make_recipe(
502            "build",
503            vec![RecipeAttribute::Object(
504                [("group".to_string(), Some("allow-agent".to_string()))]
505                    .into_iter()
506                    .collect(),
507            )],
508        );
509        assert!(has_allow_agent_group_attribute(&recipe));
510    }
511
512    #[test]
513    fn has_allow_agent_group_attribute_false_no_attrs() {
514        let recipe = make_recipe("deploy", vec![]);
515        assert!(!has_allow_agent_group_attribute(&recipe));
516    }
517
518    #[test]
519    fn has_allow_agent_group_attribute_false_other_group() {
520        let recipe = make_recipe(
521            "build",
522            vec![RecipeAttribute::Object(
523                [("group".to_string(), Some("ci".to_string()))]
524                    .into_iter()
525                    .collect(),
526            )],
527        );
528        assert!(!has_allow_agent_group_attribute(&recipe));
529    }
530
531    #[test]
532    fn has_allow_agent_group_attribute_false_legacy_agent_literal() {
533        // The bare 'agent' literal is no longer recognized; only 'allow-agent'
534        // matches Pattern A. This guards against accidental regressions.
535        let recipe = make_recipe(
536            "build",
537            vec![RecipeAttribute::Object(
538                [("group".to_string(), Some("agent".to_string()))]
539                    .into_iter()
540                    .collect(),
541            )],
542        );
543        assert!(!has_allow_agent_group_attribute(&recipe));
544    }
545
546    #[test]
547    fn has_allow_agent_doc_true() {
548        let recipe = make_recipe_with_doc("build", vec![], Some("[allow-agent]"));
549        assert!(has_allow_agent_doc(&recipe));
550    }
551
552    #[test]
553    fn has_allow_agent_doc_false_no_doc() {
554        let recipe = make_recipe("build", vec![]);
555        assert!(!has_allow_agent_doc(&recipe));
556    }
557
558    #[test]
559    fn has_allow_agent_doc_false_other_doc() {
560        let recipe = make_recipe_with_doc("build", vec![], Some("Build the project"));
561        assert!(!has_allow_agent_doc(&recipe));
562    }
563
564    #[test]
565    fn has_allow_agent_doc_false_substring_in_prose() {
566        // Prose mentioning the marker as part of a sentence must not match.
567        let recipe = make_recipe_with_doc(
568            "build",
569            vec![],
570            Some("do not add-[allow-agent]-here casually"),
571        );
572        assert!(!has_allow_agent_doc(&recipe));
573    }
574
575    #[test]
576    fn has_allow_agent_doc_true_with_surrounding_whitespace() {
577        let recipe = make_recipe_with_doc("build", vec![], Some("  [allow-agent]  "));
578        assert!(has_allow_agent_doc(&recipe));
579    }
580
581    #[test]
582    fn is_allow_agent_pattern_a() {
583        let recipe = make_recipe(
584            "build",
585            vec![RecipeAttribute::Object(
586                [("group".to_string(), Some("allow-agent".to_string()))]
587                    .into_iter()
588                    .collect(),
589            )],
590        );
591        assert!(is_allow_agent(&recipe));
592    }
593
594    #[test]
595    fn is_allow_agent_pattern_b() {
596        let recipe = make_recipe_with_doc("build", vec![], Some("[allow-agent]"));
597        assert!(is_allow_agent(&recipe));
598    }
599
600    #[test]
601    fn is_allow_agent_pattern_a_plus_other_groups() {
602        // A recipe with multiple stacked group attributes including
603        // `allow-agent` stays agent-safe. This is the just-native form
604        // (one `[group(...)]` attribute per line).
605        let recipe = make_recipe(
606            "build",
607            vec![
608                RecipeAttribute::Object(
609                    [("group".to_string(), Some("allow-agent".to_string()))]
610                        .into_iter()
611                        .collect(),
612                ),
613                RecipeAttribute::Object(
614                    [("group".to_string(), Some("profile".to_string()))]
615                        .into_iter()
616                        .collect(),
617                ),
618            ],
619        );
620        assert!(is_allow_agent(&recipe));
621    }
622
623    #[test]
624    fn is_allow_agent_neither() {
625        let recipe = make_recipe("deploy", vec![]);
626        assert!(!is_allow_agent(&recipe));
627    }
628
629    #[test]
630    fn is_allow_agent_non_agent_group_only() {
631        // Previously this case would be mistakenly filtered out when the user had
632        // both a `# [allow-agent]` comment and a `[group('profile')]` attribute,
633        // because the source-text scanner tripped on the attribute line.
634        // The doc-based fallback now handles it correctly.
635        let recipe = make_recipe_with_doc(
636            "foo",
637            vec![RecipeAttribute::Object(
638                [("group".to_string(), Some("profile".to_string()))]
639                    .into_iter()
640                    .collect(),
641            )],
642            Some("[allow-agent]"),
643        );
644        assert!(is_allow_agent(&recipe));
645    }
646
647    #[test]
648    fn resolve_justfile_path_override() {
649        let p = resolve_justfile_path(Some("/custom/justfile"), None);
650        assert_eq!(p, PathBuf::from("/custom/justfile"));
651    }
652
653    #[test]
654    fn resolve_justfile_path_default() {
655        let p = resolve_justfile_path(None, None);
656        assert_eq!(p, PathBuf::from("justfile"));
657    }
658
659    #[test]
660    fn resolve_justfile_path_with_workdir() {
661        let workdir = Path::new("/some/project");
662        let p = resolve_justfile_path(None, Some(workdir));
663        assert_eq!(p, PathBuf::from("/some/project/justfile"));
664    }
665
666    #[test]
667    fn resolve_justfile_path_override_ignores_workdir() {
668        // override_path takes precedence over workdir
669        let workdir = Path::new("/some/project");
670        let p = resolve_justfile_path(Some("/custom/justfile"), Some(workdir));
671        assert_eq!(p, PathBuf::from("/custom/justfile"));
672    }
673
674    // -------------------------------------------------------------------------
675    // truncate_output tests
676    // -------------------------------------------------------------------------
677
678    #[test]
679    fn truncate_output_short_input_unchanged() {
680        let input = "hello";
681        let (result, truncated) = truncate_output(input);
682        assert!(!truncated);
683        assert_eq!(result, input);
684    }
685
686    #[test]
687    fn truncate_output_long_input_truncated() {
688        // Create a string longer than MAX_OUTPUT_BYTES (100 KB)
689        let input = "x".repeat(200 * 1024);
690        let (result, truncated) = truncate_output(&input);
691        assert!(truncated);
692        assert!(result.contains("...[truncated"));
693        // Result should be smaller than the input
694        assert!(result.len() < input.len());
695    }
696
697    #[test]
698    fn truncate_output_utf8_boundary() {
699        // Build a string that is just over HEAD_BYTES using multi-byte chars
700        // Each '日' is 3 bytes; we need HEAD_BYTES+1 bytes to trigger truncation
701        let char_3bytes = '日';
702        // Fill slightly above MAX_OUTPUT_BYTES boundary
703        let count = (MAX_OUTPUT_BYTES / 3) + 10;
704        let input: String = std::iter::repeat_n(char_3bytes, count).collect();
705        let (result, truncated) = truncate_output(&input);
706        // Verify the result is valid UTF-8 (no panic = success)
707        assert!(std::str::from_utf8(result.as_bytes()).is_ok());
708        if truncated {
709            assert!(result.contains("...[truncated"));
710        }
711    }
712
713    // -------------------------------------------------------------------------
714    // validate_arg_value tests
715    // -------------------------------------------------------------------------
716
717    #[test]
718    fn validate_arg_value_safe_values() {
719        assert!(validate_arg_value("hello world").is_ok());
720        assert!(validate_arg_value("value_123-abc").is_ok());
721        assert!(validate_arg_value("path/to/file.txt").is_ok());
722    }
723
724    #[test]
725    fn validate_arg_value_semicolon_rejected() {
726        assert!(validate_arg_value("foo; rm -rf /").is_err());
727    }
728
729    #[test]
730    fn validate_arg_value_pipe_rejected() {
731        assert!(validate_arg_value("foo | cat /etc/passwd").is_err());
732    }
733
734    #[test]
735    fn validate_arg_value_and_and_rejected() {
736        assert!(validate_arg_value("foo && evil").is_err());
737    }
738
739    #[test]
740    fn validate_arg_value_backtick_rejected() {
741        assert!(validate_arg_value("foo`id`").is_err());
742    }
743
744    #[test]
745    fn validate_arg_value_dollar_paren_rejected() {
746        assert!(validate_arg_value("$(id)").is_err());
747    }
748
749    #[test]
750    fn validate_arg_value_newline_rejected() {
751        assert!(validate_arg_value("foo\nbar").is_err());
752    }
753
754    // -------------------------------------------------------------------------
755    // TaskLogStore tests
756    // -------------------------------------------------------------------------
757
758    fn make_execution(id: &str, task_name: &str) -> TaskExecution {
759        TaskExecution {
760            id: id.to_string(),
761            task_name: task_name.to_string(),
762            args: HashMap::new(),
763            exit_code: Some(0),
764            stdout: "".to_string(),
765            stderr: "".to_string(),
766            started_at: 0,
767            duration_ms: 0,
768            truncated: false,
769        }
770    }
771
772    #[test]
773    fn task_log_store_push_and_get() {
774        let store = TaskLogStore::new(10);
775        let exec = make_execution("id-1", "build");
776        store.push(exec);
777        let retrieved = store.get("id-1").expect("should find id-1");
778        assert_eq!(retrieved.task_name, "build");
779    }
780
781    #[test]
782    fn task_log_store_get_missing() {
783        let store = TaskLogStore::new(10);
784        assert!(store.get("nonexistent").is_none());
785    }
786
787    #[test]
788    fn task_log_store_evicts_oldest_when_full() {
789        let store = TaskLogStore::new(3);
790        store.push(make_execution("id-1", "a"));
791        store.push(make_execution("id-2", "b"));
792        store.push(make_execution("id-3", "c"));
793        store.push(make_execution("id-4", "d")); // evicts id-1
794        assert!(store.get("id-1").is_none(), "id-1 should be evicted");
795        assert!(store.get("id-4").is_some(), "id-4 should exist");
796    }
797
798    #[test]
799    fn task_log_store_recent_newest_first() {
800        let store = TaskLogStore::new(10);
801        store.push(make_execution("id-1", "a"));
802        store.push(make_execution("id-2", "b"));
803        store.push(make_execution("id-3", "c"));
804        let recent = store.recent(2);
805        assert_eq!(recent.len(), 2);
806        assert_eq!(recent[0].id, "id-3", "newest should be first");
807        assert_eq!(recent[1].id, "id-2");
808    }
809
810    #[test]
811    fn task_log_store_recent_n_larger_than_store() {
812        let store = TaskLogStore::new(10);
813        store.push(make_execution("id-1", "a"));
814        let recent = store.recent(5);
815        assert_eq!(recent.len(), 1);
816    }
817}