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icydb_core/db/query/intent/
query.rs

1//! Module: query::intent::query
2//! Responsibility: typed query-intent construction and planner handoff for entity queries.
3//! Does not own: runtime execution semantics or access-path execution behavior.
4//! Boundary: exposes query APIs and emits planner-owned compiled query contracts.
5
6use crate::{
7    db::{
8        predicate::{CoercionId, CompareOp, MissingRowPolicy, Predicate},
9        query::{
10            builder::aggregate::AggregateExpr,
11            explain::{
12                ExplainAccessPath, ExplainExecutionNodeDescriptor, ExplainExecutionNodeType,
13                ExplainOrderPushdown, ExplainPlan, ExplainPredicate,
14            },
15            expr::{FilterExpr, SortExpr},
16            intent::{QueryError, access_plan_to_entity_keys, model::QueryModel},
17            plan::{AccessPlannedQuery, LoadSpec, QueryMode},
18        },
19    },
20    traits::{EntityKind, EntityValue, SingletonEntity},
21    value::Value,
22};
23
24///
25/// Query
26///
27/// Typed, declarative query intent for a specific entity type.
28///
29/// This intent is:
30/// - schema-agnostic at construction
31/// - normalized and validated only during planning
32/// - free of access-path decisions
33///
34
35#[derive(Debug)]
36pub struct Query<E: EntityKind> {
37    intent: QueryModel<'static, E::Key>,
38}
39
40impl<E: EntityKind> Query<E> {
41    /// Create a new intent with an explicit missing-row policy.
42    /// Ignore favors idempotency and may mask index/data divergence on deletes.
43    /// Use Error to surface missing rows during scan/delete execution.
44    #[must_use]
45    pub const fn new(consistency: MissingRowPolicy) -> Self {
46        Self {
47            intent: QueryModel::new(E::MODEL, consistency),
48        }
49    }
50
51    /// Return the intent mode (load vs delete).
52    #[must_use]
53    pub const fn mode(&self) -> QueryMode {
54        self.intent.mode()
55    }
56
57    #[must_use]
58    pub(crate) fn has_explicit_order(&self) -> bool {
59        self.intent.has_explicit_order()
60    }
61
62    #[must_use]
63    pub(crate) const fn has_grouping(&self) -> bool {
64        self.intent.has_grouping()
65    }
66
67    #[must_use]
68    pub(crate) const fn load_spec(&self) -> Option<LoadSpec> {
69        match self.intent.mode() {
70            QueryMode::Load(spec) => Some(spec),
71            QueryMode::Delete(_) => None,
72        }
73    }
74
75    /// Add a predicate, implicitly AND-ing with any existing predicate.
76    #[must_use]
77    pub fn filter(mut self, predicate: Predicate) -> Self {
78        self.intent = self.intent.filter(predicate);
79        self
80    }
81
82    /// Apply a dynamic filter expression.
83    pub fn filter_expr(self, expr: FilterExpr) -> Result<Self, QueryError> {
84        let Self { intent } = self;
85        let intent = intent.filter_expr(expr)?;
86
87        Ok(Self { intent })
88    }
89
90    /// Apply a dynamic sort expression.
91    pub fn sort_expr(self, expr: SortExpr) -> Result<Self, QueryError> {
92        let Self { intent } = self;
93        let intent = intent.sort_expr(expr)?;
94
95        Ok(Self { intent })
96    }
97
98    /// Append an ascending sort key.
99    #[must_use]
100    pub fn order_by(mut self, field: impl AsRef<str>) -> Self {
101        self.intent = self.intent.order_by(field);
102        self
103    }
104
105    /// Append a descending sort key.
106    #[must_use]
107    pub fn order_by_desc(mut self, field: impl AsRef<str>) -> Self {
108        self.intent = self.intent.order_by_desc(field);
109        self
110    }
111
112    /// Enable DISTINCT semantics for this query.
113    #[must_use]
114    pub fn distinct(mut self) -> Self {
115        self.intent = self.intent.distinct();
116        self
117    }
118
119    /// Add one GROUP BY field.
120    pub fn group_by(self, field: impl AsRef<str>) -> Result<Self, QueryError> {
121        let Self { intent } = self;
122        let intent = intent.push_group_field(field.as_ref())?;
123
124        Ok(Self { intent })
125    }
126
127    /// Add one aggregate terminal via composable aggregate expression.
128    #[must_use]
129    pub fn aggregate(mut self, aggregate: AggregateExpr) -> Self {
130        self.intent = self.intent.push_group_aggregate(aggregate);
131        self
132    }
133
134    /// Override grouped hard limits for grouped execution budget enforcement.
135    #[must_use]
136    pub fn grouped_limits(mut self, max_groups: u64, max_group_bytes: u64) -> Self {
137        self.intent = self.intent.grouped_limits(max_groups, max_group_bytes);
138        self
139    }
140
141    /// Add one grouped HAVING compare clause over one grouped key field.
142    pub fn having_group(
143        self,
144        field: impl AsRef<str>,
145        op: CompareOp,
146        value: Value,
147    ) -> Result<Self, QueryError> {
148        let field = field.as_ref().to_owned();
149        let Self { intent } = self;
150        let intent = intent.push_having_group_clause(&field, op, value)?;
151
152        Ok(Self { intent })
153    }
154
155    /// Add one grouped HAVING compare clause over one grouped aggregate output.
156    pub fn having_aggregate(
157        self,
158        aggregate_index: usize,
159        op: CompareOp,
160        value: Value,
161    ) -> Result<Self, QueryError> {
162        let Self { intent } = self;
163        let intent = intent.push_having_aggregate_clause(aggregate_index, op, value)?;
164
165        Ok(Self { intent })
166    }
167
168    /// Set the access path to a single primary key lookup.
169    pub(crate) fn by_id(self, id: E::Key) -> Self {
170        let Self { intent } = self;
171        Self {
172            intent: intent.by_id(id),
173        }
174    }
175
176    /// Set the access path to a primary key batch lookup.
177    pub(crate) fn by_ids<I>(self, ids: I) -> Self
178    where
179        I: IntoIterator<Item = E::Key>,
180    {
181        let Self { intent } = self;
182        Self {
183            intent: intent.by_ids(ids),
184        }
185    }
186
187    /// Mark this intent as a delete query.
188    #[must_use]
189    pub fn delete(mut self) -> Self {
190        self.intent = self.intent.delete();
191        self
192    }
193
194    /// Apply a limit to the current mode.
195    ///
196    /// Load limits bound result size; delete limits bound mutation size.
197    /// For scalar load queries, any use of `limit` or `offset` requires an
198    /// explicit `order_by(...)` so pagination is deterministic.
199    /// GROUP BY queries use canonical grouped-key order by default.
200    #[must_use]
201    pub fn limit(mut self, limit: u32) -> Self {
202        self.intent = self.intent.limit(limit);
203        self
204    }
205
206    /// Apply an offset to a load intent.
207    ///
208    /// Scalar pagination requires an explicit `order_by(...)`.
209    /// GROUP BY queries use canonical grouped-key order by default.
210    /// Delete intents reject `offset(...)` during planning.
211    #[must_use]
212    pub fn offset(mut self, offset: u32) -> Self {
213        self.intent = self.intent.offset(offset);
214        self
215    }
216
217    /// Explain this intent without executing it.
218    pub fn explain(&self) -> Result<ExplainPlan, QueryError> {
219        let plan = self.planned()?;
220
221        Ok(plan.explain())
222    }
223
224    /// Return a stable plan hash for this intent.
225    ///
226    /// The hash is derived from canonical planner contracts and is suitable
227    /// for diagnostics, explain diffing, and cache key construction.
228    pub fn plan_hash_hex(&self) -> Result<String, QueryError> {
229        let plan = self.build_plan()?;
230
231        Ok(plan.fingerprint().to_string())
232    }
233
234    /// Explain executor-selected scalar load execution shape without running it.
235    pub fn explain_execution(&self) -> Result<ExplainExecutionNodeDescriptor, QueryError>
236    where
237        E: EntityValue,
238    {
239        let executable = self.plan()?.into_executable();
240
241        executable
242            .explain_load_execution_node_descriptor()
243            .map_err(QueryError::execute)
244    }
245
246    /// Explain executor-selected scalar load execution shape as deterministic text.
247    pub fn explain_execution_text(&self) -> Result<String, QueryError>
248    where
249        E: EntityValue,
250    {
251        Ok(self.explain_execution()?.render_text_tree())
252    }
253
254    /// Explain executor-selected scalar load execution shape as canonical JSON.
255    pub fn explain_execution_json(&self) -> Result<String, QueryError>
256    where
257        E: EntityValue,
258    {
259        Ok(self.explain_execution()?.render_json_canonical())
260    }
261
262    /// Explain executor-selected scalar load execution shape with route diagnostics.
263    pub fn explain_execution_verbose(&self) -> Result<String, QueryError>
264    where
265        E: EntityValue,
266    {
267        let executable = self.plan()?.into_executable();
268        let descriptor = executable
269            .explain_load_execution_node_descriptor()
270            .map_err(QueryError::execute)?;
271        let route_diagnostics = executable
272            .explain_load_execution_verbose_diagnostics()
273            .map_err(QueryError::execute)?;
274        let explain = self.explain()?;
275
276        // Phase 1: render descriptor tree with node-local metadata.
277        let mut lines = vec![descriptor.render_text_tree_verbose()];
278        lines.extend(route_diagnostics);
279
280        // Phase 2: add descriptor-stage summaries for key execution operators.
281        lines.push(format!(
282            "diagnostic.descriptor.has_top_n_seek={}",
283            contains_execution_node_type(&descriptor, ExplainExecutionNodeType::TopNSeek)
284        ));
285        lines.push(format!(
286            "diagnostic.descriptor.has_index_range_limit_pushdown={}",
287            contains_execution_node_type(
288                &descriptor,
289                ExplainExecutionNodeType::IndexRangeLimitPushdown,
290            )
291        ));
292        lines.push(format!(
293            "diagnostic.descriptor.has_index_predicate_prefilter={}",
294            contains_execution_node_type(
295                &descriptor,
296                ExplainExecutionNodeType::IndexPredicatePrefilter,
297            )
298        ));
299        lines.push(format!(
300            "diagnostic.descriptor.has_residual_predicate_filter={}",
301            contains_execution_node_type(
302                &descriptor,
303                ExplainExecutionNodeType::ResidualPredicateFilter,
304            )
305        ));
306
307        // Phase 3: append logical-plan diagnostics relevant to verbose explain.
308        lines.push(format!("diagnostic.plan.mode={:?}", explain.mode()));
309        lines.push(format!(
310            "diagnostic.plan.order_pushdown={}",
311            plan_order_pushdown_label(explain.order_pushdown())
312        ));
313        lines.push(format!(
314            "diagnostic.plan.predicate_pushdown={}",
315            plan_predicate_pushdown_label(explain.predicate(), explain.access())
316        ));
317        lines.push(format!("diagnostic.plan.distinct={}", explain.distinct()));
318        lines.push(format!("diagnostic.plan.page={:?}", explain.page()));
319        lines.push(format!(
320            "diagnostic.plan.consistency={:?}",
321            explain.consistency()
322        ));
323
324        Ok(lines.join("\n"))
325    }
326
327    /// Plan this intent into a neutral planned query contract.
328    pub fn planned(&self) -> Result<PlannedQuery<E>, QueryError> {
329        let plan = self.build_plan()?;
330        let _projection = plan.projection_spec(E::MODEL);
331
332        Ok(PlannedQuery::new(plan))
333    }
334
335    /// Compile this intent into query-owned handoff state.
336    ///
337    /// This boundary intentionally does not expose executor runtime shape.
338    pub fn plan(&self) -> Result<CompiledQuery<E>, QueryError> {
339        let plan = self.build_plan()?;
340        let _projection = plan.projection_spec(E::MODEL);
341
342        Ok(CompiledQuery::new(plan))
343    }
344
345    // Build a logical plan for the current intent.
346    fn build_plan(&self) -> Result<AccessPlannedQuery<E::Key>, QueryError> {
347        let plan_value = self.intent.build_plan_model()?;
348        let (logical, access) = plan_value.into_parts();
349        let access = access_plan_to_entity_keys::<E>(E::MODEL, access)?;
350        let plan = AccessPlannedQuery::from_parts(logical, access);
351
352        Ok(plan)
353    }
354}
355
356fn contains_execution_node_type(
357    descriptor: &ExplainExecutionNodeDescriptor,
358    target: ExplainExecutionNodeType,
359) -> bool {
360    descriptor.node_type() == target
361        || descriptor
362            .children()
363            .iter()
364            .any(|child| contains_execution_node_type(child, target))
365}
366
367fn plan_order_pushdown_label(order_pushdown: &ExplainOrderPushdown) -> String {
368    match order_pushdown {
369        ExplainOrderPushdown::MissingModelContext => "missing_model_context".to_string(),
370        ExplainOrderPushdown::EligibleSecondaryIndex { index, prefix_len } => {
371            format!("eligible(index={index},prefix_len={prefix_len})",)
372        }
373        ExplainOrderPushdown::Rejected(reason) => format!("rejected({reason:?})"),
374    }
375}
376
377fn plan_predicate_pushdown_label(
378    predicate: &ExplainPredicate,
379    access: &ExplainAccessPath,
380) -> String {
381    let access_label = match access {
382        ExplainAccessPath::ByKey { .. } => "by_key",
383        ExplainAccessPath::ByKeys { keys } if keys.is_empty() => "empty_access_contract",
384        ExplainAccessPath::ByKeys { .. } => "by_keys",
385        ExplainAccessPath::KeyRange { .. } => "key_range",
386        ExplainAccessPath::IndexPrefix { .. } => "index_prefix",
387        ExplainAccessPath::IndexMultiLookup { .. } => "index_multi_lookup",
388        ExplainAccessPath::IndexRange { .. } => "index_range",
389        ExplainAccessPath::FullScan => "full_scan",
390        ExplainAccessPath::Union(_) => "union",
391        ExplainAccessPath::Intersection(_) => "intersection",
392    };
393    if matches!(predicate, ExplainPredicate::None) {
394        return "none".to_string();
395    }
396    if matches!(access, ExplainAccessPath::FullScan) {
397        if explain_predicate_contains_non_strict_compare(predicate) {
398            return "fallback(non_strict_compare_coercion)".to_string();
399        }
400        if explain_predicate_contains_empty_prefix_starts_with(predicate) {
401            return "fallback(starts_with_empty_prefix)".to_string();
402        }
403        if explain_predicate_contains_is_null(predicate) {
404            return "fallback(is_null_full_scan)".to_string();
405        }
406        if explain_predicate_contains_text_scan_operator(predicate) {
407            return "fallback(text_operator_full_scan)".to_string();
408        }
409
410        return format!("fallback({access_label})");
411    }
412
413    format!("applied({access_label})")
414}
415
416fn explain_predicate_contains_non_strict_compare(predicate: &ExplainPredicate) -> bool {
417    match predicate {
418        ExplainPredicate::Compare { coercion, .. } => coercion.id != CoercionId::Strict,
419        ExplainPredicate::And(children) | ExplainPredicate::Or(children) => children
420            .iter()
421            .any(explain_predicate_contains_non_strict_compare),
422        ExplainPredicate::Not(inner) => explain_predicate_contains_non_strict_compare(inner),
423        ExplainPredicate::None
424        | ExplainPredicate::True
425        | ExplainPredicate::False
426        | ExplainPredicate::IsNull { .. }
427        | ExplainPredicate::IsMissing { .. }
428        | ExplainPredicate::IsEmpty { .. }
429        | ExplainPredicate::IsNotEmpty { .. }
430        | ExplainPredicate::TextContains { .. }
431        | ExplainPredicate::TextContainsCi { .. } => false,
432    }
433}
434
435fn explain_predicate_contains_is_null(predicate: &ExplainPredicate) -> bool {
436    match predicate {
437        ExplainPredicate::IsNull { .. } => true,
438        ExplainPredicate::And(children) | ExplainPredicate::Or(children) => {
439            children.iter().any(explain_predicate_contains_is_null)
440        }
441        ExplainPredicate::Not(inner) => explain_predicate_contains_is_null(inner),
442        ExplainPredicate::None
443        | ExplainPredicate::True
444        | ExplainPredicate::False
445        | ExplainPredicate::Compare { .. }
446        | ExplainPredicate::IsMissing { .. }
447        | ExplainPredicate::IsEmpty { .. }
448        | ExplainPredicate::IsNotEmpty { .. }
449        | ExplainPredicate::TextContains { .. }
450        | ExplainPredicate::TextContainsCi { .. } => false,
451    }
452}
453
454fn explain_predicate_contains_empty_prefix_starts_with(predicate: &ExplainPredicate) -> bool {
455    match predicate {
456        ExplainPredicate::Compare {
457            op: CompareOp::StartsWith,
458            value: Value::Text(prefix),
459            ..
460        } => prefix.is_empty(),
461        ExplainPredicate::And(children) | ExplainPredicate::Or(children) => children
462            .iter()
463            .any(explain_predicate_contains_empty_prefix_starts_with),
464        ExplainPredicate::Not(inner) => explain_predicate_contains_empty_prefix_starts_with(inner),
465        ExplainPredicate::None
466        | ExplainPredicate::True
467        | ExplainPredicate::False
468        | ExplainPredicate::Compare { .. }
469        | ExplainPredicate::IsNull { .. }
470        | ExplainPredicate::IsMissing { .. }
471        | ExplainPredicate::IsEmpty { .. }
472        | ExplainPredicate::IsNotEmpty { .. }
473        | ExplainPredicate::TextContains { .. }
474        | ExplainPredicate::TextContainsCi { .. } => false,
475    }
476}
477
478fn explain_predicate_contains_text_scan_operator(predicate: &ExplainPredicate) -> bool {
479    match predicate {
480        ExplainPredicate::Compare {
481            op: CompareOp::EndsWith,
482            ..
483        }
484        | ExplainPredicate::TextContains { .. }
485        | ExplainPredicate::TextContainsCi { .. } => true,
486        ExplainPredicate::And(children) | ExplainPredicate::Or(children) => children
487            .iter()
488            .any(explain_predicate_contains_text_scan_operator),
489        ExplainPredicate::Not(inner) => explain_predicate_contains_text_scan_operator(inner),
490        ExplainPredicate::Compare { .. }
491        | ExplainPredicate::None
492        | ExplainPredicate::True
493        | ExplainPredicate::False
494        | ExplainPredicate::IsNull { .. }
495        | ExplainPredicate::IsMissing { .. }
496        | ExplainPredicate::IsEmpty { .. }
497        | ExplainPredicate::IsNotEmpty { .. } => false,
498    }
499}
500
501impl<E> Query<E>
502where
503    E: EntityKind + SingletonEntity,
504    E::Key: Default,
505{
506    /// Set the access path to the singleton primary key.
507    pub(crate) fn only(self) -> Self {
508        let Self { intent } = self;
509
510        Self {
511            intent: intent.only(E::Key::default()),
512        }
513    }
514}
515
516///
517/// PlannedQuery
518///
519/// Neutral query-owned planned contract produced by query planning.
520/// Stores logical + access shape without executor compilation state.
521///
522
523#[derive(Debug)]
524pub struct PlannedQuery<E: EntityKind> {
525    plan: AccessPlannedQuery<E::Key>,
526}
527
528impl<E: EntityKind> PlannedQuery<E> {
529    #[must_use]
530    pub(in crate::db) const fn new(plan: AccessPlannedQuery<E::Key>) -> Self {
531        Self { plan }
532    }
533
534    #[must_use]
535    pub fn explain(&self) -> ExplainPlan {
536        self.plan.explain_with_model(E::MODEL)
537    }
538
539    /// Return the stable plan hash for this planned query.
540    #[must_use]
541    pub fn plan_hash_hex(&self) -> String {
542        self.plan.fingerprint().to_string()
543    }
544}
545
546///
547/// CompiledQuery
548///
549/// Query-owned compiled handoff produced by `Query::plan()`.
550/// This type intentionally carries only logical/access query semantics.
551/// Executor runtime shape is derived explicitly at the executor boundary.
552///
553
554#[derive(Clone, Debug)]
555pub struct CompiledQuery<E: EntityKind> {
556    plan: AccessPlannedQuery<E::Key>,
557}
558
559impl<E: EntityKind> CompiledQuery<E> {
560    #[must_use]
561    pub(in crate::db) const fn new(plan: AccessPlannedQuery<E::Key>) -> Self {
562        Self { plan }
563    }
564
565    #[must_use]
566    pub fn explain(&self) -> ExplainPlan {
567        self.plan.explain_with_model(E::MODEL)
568    }
569
570    /// Return the stable plan hash for this compiled query.
571    #[must_use]
572    pub fn plan_hash_hex(&self) -> String {
573        self.plan.fingerprint().to_string()
574    }
575
576    /// Borrow planner-lowered projection semantics for this compiled query.
577    #[must_use]
578    #[cfg(test)]
579    pub(crate) fn projection_spec(&self) -> crate::db::query::plan::expr::ProjectionSpec {
580        self.plan.projection_spec(E::MODEL)
581    }
582
583    #[must_use]
584    pub(in crate::db) fn into_inner(self) -> AccessPlannedQuery<E::Key> {
585        self.plan
586    }
587}
588
589///
590/// TESTS
591///
592
593#[cfg(test)]
594mod tests {
595    use super::*;
596    use crate::{db::predicate::CoercionSpec, types::Ulid};
597
598    fn strict_compare(field: &str, op: CompareOp, value: Value) -> ExplainPredicate {
599        ExplainPredicate::Compare {
600            field: field.to_string(),
601            op,
602            value,
603            coercion: CoercionSpec::new(CoercionId::Strict),
604        }
605    }
606
607    #[test]
608    fn predicate_pushdown_label_prefix_like_and_equivalent_range_share_label() {
609        let starts_with_predicate = strict_compare(
610            "name",
611            CompareOp::StartsWith,
612            Value::Text("foo".to_string()),
613        );
614        let equivalent_range_predicate = ExplainPredicate::And(vec![
615            strict_compare("name", CompareOp::Gte, Value::Text("foo".to_string())),
616            strict_compare("name", CompareOp::Lt, Value::Text("fop".to_string())),
617        ]);
618        let access = ExplainAccessPath::IndexRange {
619            name: "idx_name",
620            fields: vec!["name"],
621            prefix_len: 0,
622            prefix: Vec::new(),
623            lower: std::ops::Bound::Included(Value::Text("foo".to_string())),
624            upper: std::ops::Bound::Excluded(Value::Text("fop".to_string())),
625        };
626
627        assert_eq!(
628            plan_predicate_pushdown_label(&starts_with_predicate, &access),
629            plan_predicate_pushdown_label(&equivalent_range_predicate, &access),
630            "equivalent prefix-like and bounded-range shapes should report identical pushdown reason labels",
631        );
632        assert_eq!(
633            plan_predicate_pushdown_label(&starts_with_predicate, &access),
634            "applied(index_range)"
635        );
636    }
637
638    #[test]
639    fn predicate_pushdown_label_distinguishes_is_null_and_non_strict_full_scan_fallbacks() {
640        let is_null_predicate = ExplainPredicate::IsNull {
641            field: "group".to_string(),
642        };
643        let non_strict_predicate = ExplainPredicate::Compare {
644            field: "group".to_string(),
645            op: CompareOp::Eq,
646            value: Value::Uint(7),
647            coercion: CoercionSpec::new(CoercionId::NumericWiden),
648        };
649        let access = ExplainAccessPath::FullScan;
650
651        assert_eq!(
652            plan_predicate_pushdown_label(&is_null_predicate, &access),
653            "fallback(is_null_full_scan)"
654        );
655        assert_eq!(
656            plan_predicate_pushdown_label(&non_strict_predicate, &access),
657            "fallback(non_strict_compare_coercion)"
658        );
659    }
660
661    #[test]
662    fn predicate_pushdown_label_reports_none_when_no_predicate_is_present() {
663        let predicate = ExplainPredicate::None;
664        let access = ExplainAccessPath::ByKey {
665            key: Value::Ulid(Ulid::from_u128(7)),
666        };
667
668        assert_eq!(plan_predicate_pushdown_label(&predicate, &access), "none");
669    }
670
671    #[test]
672    fn predicate_pushdown_label_reports_empty_access_contract_for_impossible_shapes() {
673        let predicate = ExplainPredicate::Or(vec![
674            ExplainPredicate::IsNull {
675                field: "id".to_string(),
676            },
677            ExplainPredicate::And(vec![
678                ExplainPredicate::Compare {
679                    field: "id".to_string(),
680                    op: CompareOp::In,
681                    value: Value::List(Vec::new()),
682                    coercion: CoercionSpec::new(CoercionId::Strict),
683                },
684                ExplainPredicate::True,
685            ]),
686        ]);
687        let access = ExplainAccessPath::ByKeys { keys: Vec::new() };
688
689        assert_eq!(
690            plan_predicate_pushdown_label(&predicate, &access),
691            "applied(empty_access_contract)"
692        );
693    }
694
695    #[test]
696    fn predicate_pushdown_label_distinguishes_empty_prefix_starts_with_full_scan_fallback() {
697        let empty_prefix_predicate = ExplainPredicate::Compare {
698            field: "label".to_string(),
699            op: CompareOp::StartsWith,
700            value: Value::Text(String::new()),
701            coercion: CoercionSpec::new(CoercionId::Strict),
702        };
703        let non_empty_prefix_predicate = ExplainPredicate::Compare {
704            field: "label".to_string(),
705            op: CompareOp::StartsWith,
706            value: Value::Text("l".to_string()),
707            coercion: CoercionSpec::new(CoercionId::Strict),
708        };
709        let access = ExplainAccessPath::FullScan;
710
711        assert_eq!(
712            plan_predicate_pushdown_label(&empty_prefix_predicate, &access),
713            "fallback(starts_with_empty_prefix)"
714        );
715        assert_eq!(
716            plan_predicate_pushdown_label(&non_empty_prefix_predicate, &access),
717            "fallback(full_scan)"
718        );
719    }
720
721    #[test]
722    fn predicate_pushdown_label_reports_text_operator_full_scan_fallback() {
723        let text_contains = ExplainPredicate::TextContainsCi {
724            field: "label".to_string(),
725            value: Value::Text("needle".to_string()),
726        };
727        let ends_with = ExplainPredicate::Compare {
728            field: "label".to_string(),
729            op: CompareOp::EndsWith,
730            value: Value::Text("fix".to_string()),
731            coercion: CoercionSpec::new(CoercionId::Strict),
732        };
733        let access = ExplainAccessPath::FullScan;
734
735        assert_eq!(
736            plan_predicate_pushdown_label(&text_contains, &access),
737            "fallback(text_operator_full_scan)"
738        );
739        assert_eq!(
740            plan_predicate_pushdown_label(&ends_with, &access),
741            "fallback(text_operator_full_scan)"
742        );
743    }
744
745    #[test]
746    fn predicate_pushdown_label_keeps_collection_contains_on_generic_full_scan_fallback() {
747        let collection_contains = ExplainPredicate::Compare {
748            field: "tags".to_string(),
749            op: CompareOp::Contains,
750            value: Value::Uint(7),
751            coercion: CoercionSpec::new(CoercionId::CollectionElement),
752        };
753        let access = ExplainAccessPath::FullScan;
754
755        assert_eq!(
756            plan_predicate_pushdown_label(&collection_contains, &access),
757            "fallback(non_strict_compare_coercion)"
758        );
759        assert_ne!(
760            plan_predicate_pushdown_label(&collection_contains, &access),
761            "fallback(text_operator_full_scan)"
762        );
763    }
764
765    #[test]
766    fn predicate_pushdown_label_non_strict_ends_with_uses_non_strict_fallback_precedence() {
767        let non_strict_ends_with = ExplainPredicate::Compare {
768            field: "label".to_string(),
769            op: CompareOp::EndsWith,
770            value: Value::Text("fix".to_string()),
771            coercion: CoercionSpec::new(CoercionId::TextCasefold),
772        };
773        let access = ExplainAccessPath::FullScan;
774
775        assert_eq!(
776            plan_predicate_pushdown_label(&non_strict_ends_with, &access),
777            "fallback(non_strict_compare_coercion)"
778        );
779        assert_ne!(
780            plan_predicate_pushdown_label(&non_strict_ends_with, &access),
781            "fallback(text_operator_full_scan)"
782        );
783    }
784}