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lemma/
lib.rs

1//! # Lemma Engine
2//!
3//! **Rules for man and machine**
4//!
5//! Consumer API: **`load`** → **`list`** → **`show`** / **`source`** → **`run`**.
6
7#[cfg(test)]
8mod tests;
9
10pub mod api;
11pub(crate) mod computation;
12pub mod documentation;
13pub(crate) mod engine;
14pub(crate) mod error;
15pub(crate) mod evaluation;
16pub(crate) mod formatting;
17pub(crate) mod limits;
18pub(crate) mod literals;
19pub(crate) mod parsing;
20pub(crate) mod planning;
21pub mod quality;
22pub(crate) mod registry;
23pub mod result_value;
24pub(crate) mod snapshot;
25pub(crate) mod spec_set_id;
26pub(crate) mod stdlib;
27pub(crate) mod string_distance;
28
29#[cfg(not(target_arch = "wasm32"))]
30pub mod deps;
31
32#[cfg(not(target_arch = "wasm32"))]
33pub mod mcp;
34
35#[cfg(target_arch = "wasm32")]
36pub mod wasm;
37
38pub use computation::{OperationResult, VetoType};
39pub use engine::{
40    resolve_effective, Engine, Errors, ListedSpec, ResolvedRepository, EMBEDDED_STDLIB_REPOSITORY,
41};
42pub use error::{
43    EngineError, EngineErrorSource, Error, ErrorDetails, ErrorKind, RegistryErrorKind,
44    RequestErrorKind,
45};
46pub use evaluation::explanations::{format_explanation, Cause, Explanation, ExplanationNode};
47pub use evaluation::response::{Response, RuleResult};
48pub use evaluation::run_data::{
49    parse_run_data_object, resolve_run_rules, run_data_value_from_json_value, RunDataValue,
50};
51pub use formatting::{format_parse_result, format_source, format_specs};
52pub use limits::{
53    ResourceLimits, MAX_DATA_NAME_LENGTH, MAX_RULE_NAME_LENGTH, MAX_SPEC_NAME_LENGTH,
54};
55pub use literals::{DateGranularity, MeasureUnit, MeasureUnits, RatioUnit, RatioUnits};
56pub use parsing::ast::DateTimeValue;
57pub use parsing::source::SourceType;
58pub use planning::execution_plan::type_detail_lines;
59pub use planning::execution_plan::{Show, ShowData, ShowVersion};
60pub use planning::explanation::{ConversionTraceRole, SerializedConversionTraceStep};
61pub use planning::semantics::{DataPath, LemmaType, LiteralValue, TypeSpecification, ValueKind};
62pub use result_value::{CalendarResult, RangeResult, RuleResultValue, RuleResultValueFailure};
63pub use spec_set_id::parse_spec_set_id;
64pub use stdlib::UNITS_LEMMA;
65
66/// Exact rational helpers for in-tree integration tests. Not a supported consumer API.
67#[doc(hidden)]
68pub mod __test_support {
69    pub use crate::computation::rational::{
70        checked_div, checked_mul, decimal_to_rational, rational_new,
71    };
72    pub use crate::literals::TimeValue;
73    pub use crate::planning::semantics::{
74        SemanticDateTime, SemanticTime, SemanticTimezone, TypedLiteral,
75    };
76
77    /// Serializes an [`Error`](crate::Error) as [`EngineError`](crate::EngineError).
78    pub fn current_binding_error_json(error: &crate::Error) -> serde_json::Value {
79        serde_json::to_value(crate::EngineError::from(error))
80            .expect("BUG: EngineError must serialize")
81    }
82
83    #[cfg(not(target_arch = "wasm32"))]
84    pub use fixture_transport::FixtureTransport;
85
86    #[cfg(not(target_arch = "wasm32"))]
87    mod fixture_transport {
88        use crate::registry::{Fetch, Header, HttpResponse, HttpTransport, TransportFailure};
89        use std::collections::HashMap;
90        use std::path::{Path, PathBuf};
91
92        /// Offline [`HttpTransport`] over bundled (or custom) LemmaBase fixture files.
93        ///
94        /// Panics if asked for a URL that is not a LemmaBase source URL.
95        pub struct FixtureTransport {
96            fixtures: HashMap<String, String>,
97        }
98
99        impl FixtureTransport {
100            pub fn new(dir: impl AsRef<Path>) -> Self {
101                let dir = dir.as_ref();
102                let mut fixtures = HashMap::new();
103                collect_fixture_files(dir, dir, &mut fixtures);
104                Self { fixtures }
105            }
106
107            pub fn bundled() -> Self {
108                Self::new(PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("tests/registry_fixtures"))
109            }
110        }
111
112        impl HttpTransport for FixtureTransport {
113            fn get(&self, fetch: &Fetch) -> Result<HttpResponse, TransportFailure> {
114                match self.fixtures.get(&fetch.repository) {
115                    Some(body) => Ok(HttpResponse {
116                        status: 200,
117                        headers: Vec::<Header>::new(),
118                        body: body.clone(),
119                    }),
120                    None => Ok(HttpResponse {
121                        status: 404,
122                        headers: Vec::new(),
123                        body: String::new(),
124                    }),
125                }
126            }
127        }
128
129        fn collect_fixture_files(dir: &Path, base: &Path, fixtures: &mut HashMap<String, String>) {
130            let entries = std::fs::read_dir(dir)
131                .unwrap_or_else(|e| panic!("BUG: read fixture dir {}: {e}", dir.display()));
132            for entry in entries {
133                let entry = entry
134                    .unwrap_or_else(|e| panic!("BUG: fixture dir entry in {}: {e}", dir.display()));
135                let path = entry.path();
136                if path.is_dir() {
137                    collect_fixture_files(&path, base, fixtures);
138                    continue;
139                }
140                if path.extension().is_none_or(|e| e != "lemma") {
141                    continue;
142                }
143                let relative = path.strip_prefix(base).unwrap_or_else(|_| {
144                    panic!("BUG: fixture path not under base: {}", path.display())
145                });
146                let identifier = relative
147                    .with_extension("")
148                    .to_string_lossy()
149                    .replace('\\', "/");
150                let content = std::fs::read_to_string(&path)
151                    .unwrap_or_else(|e| panic!("BUG: read fixture {}: {e}", path.display()));
152                fixtures.insert(identifier, content);
153            }
154        }
155    }
156}
157
158// Tier 1 — language surface (always)
159pub use parsing::ast::{
160    try_parse_type_constraint_command, DataValue, Span, SpecRef, TimezoneValue,
161};
162pub use parsing::lexer::{Lexer, TokenKind};
163pub use parsing::source::Source;
164pub use parsing::{parse, ParseResult};
165pub use quality::Recommendation;
166
167// Tier 2 — registry resolution (sans-IO; hosts supply HttpTransport)
168pub use engine::Context;
169pub use parsing::ast::{LemmaRepository, LemmaSpec, RepositoryQualifier};
170pub use planning::LemmaSpecSet;
171pub use registry::{
172    Fetch, Header, HttpResponse, HttpTransport, Install, InstallStep, LemmaBase, Registries,
173    Registry, RegistryBundle, RegistryError, RepositoryInstallResult, Resolve, ResolveStep,
174    TransportFailure,
175};