ev/
guard.rs

1//! `ev guard "<selector>" <id> [<ground>]` — attach an existing test to a ground as a
2//! data check (after the fact). Because `check` is hashed, this writes a NEW CHILD.
3use crate::canonical::compute_id;
4use crate::store::Store;
5use crate::tick::{Check, Ground, Liveness, Tick};
6use std::path::Path;
7
8pub struct GuardArgs {
9    pub selector: String,
10    pub id: String,
11    pub target: Option<String>, // ground claim or index; required if >1 unbound ground
12    pub counter_test: String,
13    pub platforms: Vec<String>,
14    pub triggered_by: Vec<String>,
15    pub surfaces: Vec<String>,
16    pub verified_at_sha: Option<String>,
17    pub blame: Option<String>,
18    pub authority: Option<String>,
19}
20
21fn resolve_target(grounds: &[Ground], target: &Option<String>) -> Result<usize, String> {
22    let unbound: Vec<usize> = grounds
23        .iter()
24        .enumerate()
25        .filter(|(_, g)| g.check.is_none())
26        .map(|(i, _)| i)
27        .collect();
28    match target {
29        None => match unbound.as_slice() {
30            [one] => Ok(*one),
31            [] => Err("no unbound ground to guard".into()),
32            _ => Err("more than one unbound ground — name the target (claim or index)".into()),
33        },
34        Some(t) => {
35            if let Ok(idx) = t.parse::<usize>() {
36                if idx < grounds.len() {
37                    return Ok(idx);
38                }
39                return Err(format!("ground index {idx} out of range"));
40            }
41            let matches: Vec<usize> = grounds
42                .iter()
43                .enumerate()
44                .filter(|(_, g)| g.claim == *t)
45                .map(|(i, _)| i)
46                .collect();
47            match matches.as_slice() {
48                [one] => Ok(*one),
49                [] => Err(format!("no ground with claim {t:?}")),
50                _ => Err(format!("ambiguous: multiple grounds with claim {t:?}")),
51            }
52        }
53    }
54}
55
56pub fn run(repo: &Path, a: GuardArgs) -> Result<Tick, String> {
57    let store = Store::at(repo);
58    let parent = store
59        .read_tick(&a.id)
60        .map_err(|e| format!("{e}"))?
61        .ok_or(format!("no tick with id {}", a.id))?;
62    let head = store
63        .read_head()
64        .map_err(|e| format!("reading HEAD: {e}"))?;
65    if a.id != head {
66        return Err(format!(
67            "guard can only amend the current HEAD decision; {} is not HEAD ({})",
68            a.id, head
69        ));
70    }
71    let idx = resolve_target(&parent.grounds, &a.target)?;
72    let g = &parent.grounds[idx];
73    // R2: a human-rechecked (person) ground can never be force-bound to a test.
74    if let Some(Check::Person { .. }) = g.check {
75        return Err("a human-rechecked ground cannot carry a test (R2 hard error)".into());
76    }
77    // Validate authority FIRST so the rejected-road tripwire gate below reads a vetted value (and an
78    // out-of-vocab authority fails loudly rather than silently failing the user-ruled comparison).
79    if let Some(val) = &a.authority {
80        crate::capture::validate_authority(val)?;
81    }
82    // 0.1.8: a rejected road (closed by a ruling) may be guarded with a falsifiable tripwire, but
83    // ONLY when the binding declares --authority user-ruled (the human's deliberate closed-road call).
84    // Mirrors capture.rs build_ground; the counter-test stays required below (no harvested tripwire).
85    // provenance is hard-stamped human-now on the child (line below), so a guard can never create an
86    // agent-proposed gating tripwire.
87    if g.supports.starts_with("rejected:") && a.authority.as_deref() != Some("user-ruled") {
88        return Err(
89            "a rejected road can carry a tripwire test only when guarded with --authority user-ruled"
90                .into(),
91        );
92    }
93    if g.check.is_some() {
94        return Err("ground already has a check".into());
95    }
96    if a.counter_test.trim().is_empty() {
97        return Err("a test binding requires a counter-test (no vacuous binding)".into());
98    }
99    if a.platforms.is_empty() || a.triggered_by.is_empty() || a.surfaces.is_empty() {
100        return Err(
101            "a test binding requires at least one platform, triggered-by, and surface".into(),
102        );
103    }
104    let verified_at_sha = crate::capture::resolve_sha(repo, &a.verified_at_sha)?;
105    let blame = crate::capture::resolve_blame(repo, a.blame)?;
106
107    let mut grounds = parent.grounds.clone();
108    grounds[idx] = Ground {
109        claim: grounds[idx].claim.clone(),
110        supports: grounds[idx].supports.clone(),
111        check: Some(Check::Test {
112            reference: a.selector,
113            verified_at_sha,
114            counter_test: Some(a.counter_test),
115            liveness: Liveness {
116                platforms: a.platforms,
117                triggered_by: a.triggered_by,
118                surfaces: a.surfaces,
119            },
120        }),
121    };
122    let held_since = time::OffsetDateTime::now_utc()
123        .format(&time::format_description::well_known::Rfc3339)
124        .map_err(|e| format!("timestamp: {e}"))?;
125    let mut child = Tick {
126        id: String::new(),
127        parent_id: parent.id.clone(),
128        observe: parent.observe.clone(),
129        decision: parent.decision.clone(),
130        grounds,
131        status: "live".into(),
132        held_since,
133        blame,
134        authority: a.authority,
135        jurisdiction: parent.jurisdiction.clone(), // a sibling tag of the decision; inherited by the child
136        source_ref: parent.source_ref.clone(), // the opaque source identity of the decision; inherited by the child
137        // NOT inherited: provenance is a property of the authorship ACT, not the decision. A guard is a
138        // fresh human act, hard-stamped human-now (the absent default) — the launder defense.
139        provenance: None,
140    };
141    child.id = compute_id(&child);
142    store
143        .write_tick(&child)
144        .map_err(|e| format!("writing tick: {e}"))?;
145    Ok(child)
146}
147
148#[cfg(test)]
149mod tests {
150    use super::*;
151
152    fn repo_with_unbound() -> (std::path::PathBuf, String) {
153        use std::sync::atomic::{AtomicU64, Ordering};
154        static N: AtomicU64 = AtomicU64::new(0);
155        let p = std::env::temp_dir().join(format!(
156            "ev-guard-{}-{}",
157            std::process::id(),
158            N.fetch_add(1, Ordering::Relaxed)
159        ));
160        let _ = std::fs::remove_dir_all(&p);
161        std::fs::create_dir_all(&p).unwrap();
162        Store::at(&p).init().unwrap();
163        let args: Vec<String> = [
164            "--assume",
165            "schema stays frozen",
166            "--assume",
167            "team ok",
168            "--revisit",
169            "Q3",
170            "--blame",
171            "Wang Yu",
172        ]
173        .iter()
174        .map(|x| x.to_string())
175        .collect();
176        let t = crate::capture::run(&p, Some("build our own retrieval"), &args).unwrap();
177        (p, t.id)
178    }
179    fn args(selector: &str, id: &str, target: Option<&str>) -> GuardArgs {
180        GuardArgs {
181            selector: selector.into(),
182            id: id.into(),
183            target: target.map(|s| s.into()),
184            counter_test: "pytest x::counter".into(),
185            platforms: vec!["linux-ci".into()],
186            triggered_by: vec!["f".into()],
187            surfaces: vec!["s".into()],
188            verified_at_sha: Some("d308afac1b2c3d4e5f60718293a4b5c6d7e8f901".into()),
189            blame: Some("Wang Yu".into()),
190            authority: None,
191        }
192    }
193
194    #[test]
195    fn guard_should_bind_a_named_unbound_ground_and_write_a_child_when_the_target_is_named() {
196        // given: a HEAD tick with an unbound "schema stays frozen" ground
197        let (p, id) = repo_with_unbound();
198
199        // when: that named ground is guarded
200        let child = run(
201            &p,
202            args(
203                "pytest tests/test_schema_frozen.py",
204                &id,
205                Some("schema stays frozen"),
206            ),
207        )
208        .expect("ok");
209
210        // then: a child is written and the named ground now carries a test check
211        assert_eq!(child.parent_id, id);
212        let i = child
213            .grounds
214            .iter()
215            .position(|g| g.claim == "schema stays frozen")
216            .unwrap();
217        assert!(matches!(child.grounds[i].check, Some(Check::Test { .. })));
218    }
219
220    #[test]
221    fn guard_should_still_error_without_a_counter_test() {
222        // given: the migrate-only harvested path now exists; pin that the guard path is UNCHANGED
223        // — guard.rs:83-85 stays byte-for-byte strict, so an empty counter-test STILL errors here
224        // (harvesting drops the counter-test ONLY on the migrate path, never on `ev guard`).
225        let (p, id) = repo_with_unbound();
226        let mut a = args("pytest x", &id, Some("schema stays frozen"));
227        a.counter_test = "   ".into(); // an empty/whitespace counter-test is a vacuous binding
228
229        // when: that ground is guarded with no real counter-test
230        let e = run(&p, a);
231
232        // then: it errors — no vacuous binding on the guard path
233        assert!(e.is_err());
234    }
235
236    #[test]
237    fn guard_should_refuse_the_target_when_the_ground_is_human_rechecked() {
238        // given: a HEAD tick whose "team ok" ground is a human-rechecked (person) check
239        let (p, id) = repo_with_unbound();
240
241        // when: that person ground is guarded with a test
242        let e = run(&p, args("pytest x", &id, Some("team ok")));
243
244        // then: it is refused
245        assert!(e.is_err());
246    }
247
248    #[test]
249    fn guard_should_require_a_target_when_more_than_one_ground_is_unbound() {
250        // given: a HEAD tick with two unbound grounds and no target named
251        let (p, _id) = repo_with_unbound();
252        let t2 = crate::capture::run(
253            &p,
254            Some("d2"),
255            &["--assume", "a", "--assume", "b", "--blame", "Wang Yu"]
256                .iter()
257                .map(|x| x.to_string())
258                .collect::<Vec<_>>(),
259        )
260        .unwrap();
261
262        // when: the guard is run without naming a target
263        let e = run(&p, args("pytest x", &t2.id, None));
264
265        // then: it is refused
266        assert!(e.is_err());
267    }
268
269    #[test]
270    fn guard_should_refuse_the_target_when_it_is_not_head() {
271        // given: two decisions in a chain, so the first is no longer HEAD
272        let p = repo_with_unbound().0;
273        let t1 = crate::capture::run(
274            &p,
275            Some("d1"),
276            &["--assume", "a", "--blame", "Wang Yu"]
277                .iter()
278                .map(|x| x.to_string())
279                .collect::<Vec<_>>(),
280        )
281        .unwrap();
282        let _t2 = crate::capture::run(
283            &p,
284            Some("d2"),
285            &["--assume", "b", "--blame", "Wang Yu"]
286                .iter()
287                .map(|x| x.to_string())
288                .collect::<Vec<_>>(),
289        )
290        .unwrap();
291
292        // when: the non-HEAD first tick is guarded
293        let e = run(&p, args("pytest x", &t1.id, Some("a")));
294
295        // then: it is refused
296        assert!(e.is_err());
297    }
298
299    #[test]
300    fn guard_should_refuse_a_rejected_road_tripwire_when_authority_is_absent() {
301        // given: a HEAD tick whose only ground is a rejected road
302        let p = repo_with_unbound().0;
303        let t = crate::capture::run(
304            &p,
305            Some("d"),
306            &["--reject", "x: y", "--blame", "Wang Yu"]
307                .iter()
308                .map(|x| x.to_string())
309                .collect::<Vec<_>>(),
310        )
311        .unwrap();
312
313        // when: that rejected ground is guarded with a test but NO --authority user-ruled
314        let e = run(&p, args("pytest x", &t.id, Some("y")));
315
316        // then: it is refused — a rejected-road tripwire needs --authority user-ruled
317        assert!(e.is_err());
318    }
319
320    #[test]
321    fn guard_should_bind_a_tripwire_to_a_rejected_road_when_authority_is_user_ruled() {
322        // given: a HEAD tick whose only ground is a rejected road (closed by a human ruling)
323        let p = repo_with_unbound().0;
324        let t = crate::capture::run(
325            &p,
326            Some("d"),
327            &["--reject", "x: y", "--blame", "Wang Yu"]
328                .iter()
329                .map(|x| x.to_string())
330                .collect::<Vec<_>>(),
331        )
332        .unwrap();
333
334        // when: that rejected ground is guarded with a falsifiable tripwire AND --authority user-ruled
335        let mut a = args("pytest x", &t.id, Some("y"));
336        a.authority = Some("user-ruled".into());
337        let child = run(&p, a).expect("a user-ruled rejected-road tripwire binds");
338
339        // then: a child is written and the closed road now carries a test tripwire
340        assert_eq!(child.parent_id, t.id);
341        let g = child
342            .grounds
343            .iter()
344            .find(|g| g.supports.starts_with("rejected:"))
345            .expect("a rejected road");
346        assert!(matches!(g.check, Some(Check::Test { .. })));
347        // and the child is a fresh human act (provenance human-now), so it can gate
348        assert_eq!(child.provenance, None);
349    }
350}
ev/guard.rs

ev/
guard.rs
