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alef_e2e/codegen/rust/
test_file.rs

1//! Per-category test file generation for Rust e2e tests.
2
3use std::fmt::Write as FmtWrite;
4
5use crate::config::E2eConfig;
6use crate::escape::sanitize_filename;
7use crate::field_access::FieldResolver;
8use crate::fixture::{Fixture, FixtureGroup};
9
10use super::args::{emit_rust_visitor_method, render_rust_arg, resolve_visitor_trait};
11use super::assertions::render_assertion;
12use super::http::render_http_test_function;
13use super::mock_server::render_mock_server_setup;
14
15pub(super) fn resolve_function_name_for_call(call_config: &crate::config::CallConfig) -> String {
16    call_config
17        .overrides
18        .get("rust")
19        .and_then(|o| o.function.clone())
20        .unwrap_or_else(|| call_config.function.clone())
21}
22
23pub(super) fn resolve_module(e2e_config: &E2eConfig, dep_name: &str) -> String {
24    resolve_module_for_call(&e2e_config.call, dep_name)
25}
26
27pub(super) fn resolve_module_for_call(call_config: &crate::config::CallConfig, dep_name: &str) -> String {
28    // For Rust, the module name is the crate identifier (underscores).
29    // Priority: override.crate_name > override.module > dep_name
30    let overrides = call_config.overrides.get("rust");
31    overrides
32        .and_then(|o| o.crate_name.clone())
33        .or_else(|| overrides.and_then(|o| o.module.clone()))
34        .unwrap_or_else(|| dep_name.to_string())
35}
36
37pub(super) fn is_skipped(fixture: &Fixture, language: &str) -> bool {
38    fixture.skip.as_ref().is_some_and(|s| s.should_skip(language))
39}
40
41pub fn render_test_file(
42    category: &str,
43    fixtures: &[&Fixture],
44    e2e_config: &E2eConfig,
45    dep_name: &str,
46    needs_mock_server: bool,
47) -> String {
48    let mut out = String::new();
49    out.push_str(&alef_core::hash::header(alef_core::hash::CommentStyle::DoubleSlash));
50    let _ = writeln!(out, "//! E2e tests for category: {category}");
51    let _ = writeln!(out);
52
53    let module = resolve_module(e2e_config, dep_name);
54    let field_resolver = FieldResolver::new(
55        &e2e_config.fields,
56        &e2e_config.fields_optional,
57        &e2e_config.result_fields,
58        &e2e_config.fields_array,
59        &e2e_config.fields_method_calls,
60    );
61
62    // Check if this file has http-fixture tests (separate from call-based tests).
63    let file_has_http = fixtures.iter().any(|f| f.http.is_some());
64    // Call-based: has mock_response OR is a plain function-call fixture (no http, no mock) with a
65    // configured function name. Pure schema/spec stubs (function name empty) use the stub path.
66    let file_has_call_based = fixtures.iter().any(|f| {
67        if f.mock_response.is_some() {
68            return true;
69        }
70        if f.http.is_none() && f.mock_response.is_none() {
71            let call_config = e2e_config.resolve_call_for_fixture(f.call.as_deref(), &f.input);
72            let fn_name = resolve_function_name_for_call(call_config);
73            return !fn_name.is_empty();
74        }
75        false
76    });
77
78    // Collect all unique (module, function) pairs needed across call-based fixtures only.
79    // Resolve client_factory from the default call's rust override. When set, the generated tests
80    // create a client via `module::factory(...)` and call methods on it rather than importing and
81    // calling free functions. In that case we skip the function `use` imports entirely.
82    let rust_call_override = e2e_config.call.overrides.get("rust");
83    let client_factory = rust_call_override.and_then(|o| o.client_factory.as_deref());
84
85    // Http fixtures and pure stub fixtures use different code paths and don't import the call function.
86    if file_has_call_based && client_factory.is_none() {
87        let mut imported: std::collections::BTreeSet<(String, String)> = std::collections::BTreeSet::new();
88        for fixture in fixtures.iter().filter(|f| {
89            if f.mock_response.is_some() {
90                return true;
91            }
92            if f.http.is_none() && f.mock_response.is_none() {
93                let call_config = e2e_config.resolve_call_for_fixture(f.call.as_deref(), &f.input);
94                let fn_name = resolve_function_name_for_call(call_config);
95                return !fn_name.is_empty();
96            }
97            false
98        }) {
99            let call_config = e2e_config.resolve_call_for_fixture(fixture.call.as_deref(), &fixture.input);
100            let fn_name = resolve_function_name_for_call(call_config);
101            let mod_name = resolve_module_for_call(call_config, dep_name);
102            imported.insert((mod_name, fn_name));
103        }
104        // Emit use statements, grouping by module when possible.
105        let mut by_module: std::collections::BTreeMap<String, Vec<String>> = std::collections::BTreeMap::new();
106        for (mod_name, fn_name) in &imported {
107            by_module.entry(mod_name.clone()).or_default().push(fn_name.clone());
108        }
109        for (mod_name, fns) in &by_module {
110            if fns.len() == 1 {
111                let _ = writeln!(out, "use {mod_name}::{};", fns[0]);
112            } else {
113                let joined = fns.join(", ");
114                let _ = writeln!(out, "use {mod_name}::{{{joined}}};");
115            }
116        }
117    }
118
119    // Http fixtures use App + RequestContext for integration tests.
120    if file_has_http {
121        let _ = writeln!(out, "use {module}::{{App, RequestContext}};");
122    }
123
124    // Import handle constructor functions and the config type they use.
125    let has_handle_args = e2e_config.call.args.iter().any(|a| a.arg_type == "handle");
126    if has_handle_args {
127        let _ = writeln!(out, "use {module}::CrawlConfig;");
128    }
129    for arg in &e2e_config.call.args {
130        if arg.arg_type == "handle" {
131            use heck::ToSnakeCase;
132            let constructor_name = format!("create_{}", arg.name.to_snake_case());
133            let _ = writeln!(out, "use {module}::{constructor_name};");
134        }
135    }
136
137    // When client_factory is set, emit trait imports required to call methods on the client object.
138    // Traits like LlmClient, FileClient, etc. must be in scope for method dispatch to work.
139    if client_factory.is_some() && file_has_call_based {
140        let trait_imports: Vec<String> = e2e_config
141            .call
142            .overrides
143            .get("rust")
144            .map(|o| o.trait_imports.clone())
145            .unwrap_or_default();
146        for trait_name in &trait_imports {
147            let _ = writeln!(out, "use {module}::{trait_name};");
148        }
149    }
150
151    // Import mock_server and common modules when any fixture in this file uses mock_response.
152    let file_needs_mock = needs_mock_server
153        && fixtures
154            .iter()
155            .any(|f| f.mock_response.is_some() || f.needs_mock_server());
156    if file_needs_mock {
157        let _ = writeln!(out, "mod common;");
158        let _ = writeln!(out, "mod mock_server;");
159        let _ = writeln!(out, "use mock_server::{{MockRoute, MockServer}};");
160    }
161
162    // Import the visitor trait, result enum, and node context when any fixture
163    // in this file declares a `visitor` block. Without these, the inline
164    // `impl <visitor_trait> for _TestVisitor` block fails to resolve.
165    // Visitor types live in the `visitor` sub-module of the crate, not the crate root.
166    // The trait name is read from `[e2e.call.overrides.rust] visitor_trait`; omitting it
167    // while a fixture declares a visitor is a configuration error.
168    let file_needs_visitor = fixtures.iter().any(|f| f.visitor.is_some());
169    if file_needs_visitor {
170        let visitor_trait = resolve_visitor_trait(rust_call_override).unwrap_or_else(|| {
171            panic!(
172                "category '{}': fixture declares a visitor block but \
173                 `[e2e.call.overrides.rust] visitor_trait` is not configured",
174                category
175            )
176        });
177        let _ = writeln!(
178            out,
179            "use {module}::visitor::{{{visitor_trait}, NodeContext, VisitResult}};"
180        );
181    }
182
183    // When the rust override specifies an `options_type` (e.g. `ConversionOptions`),
184    // type annotations are emitted on json_object bindings so that `Default::default()`
185    // and `serde_json::from_value(…)` can be resolved without a trailing positional arg.
186    // Import the named type so it is in scope in every test function in this file.
187    if file_has_call_based {
188        let rust_options_type = e2e_config
189            .call
190            .overrides
191            .get("rust")
192            .and_then(|o| o.options_type.as_deref());
193        if let Some(opts_type) = rust_options_type {
194            // Only emit if the call has a json_object arg (the type annotation is only
195            // added to json_object bindings).
196            let has_json_object_arg = e2e_config.call.args.iter().any(|a| a.arg_type == "json_object");
197            if has_json_object_arg {
198                let _ = writeln!(out, "use {module}::{opts_type};");
199            }
200        }
201    }
202
203    // Collect and import element types from json_object args that have an element_type specified.
204    // These types are used in serde_json::from_value::<Vec<{elem}>>() for batch operations.
205    // Collect from all calls used in call-based fixtures (not just the default call).
206    if file_has_call_based {
207        let mut element_types: std::collections::BTreeSet<String> = std::collections::BTreeSet::new();
208        for fixture in fixtures.iter().filter(|f| {
209            if f.mock_response.is_some() {
210                return true;
211            }
212            if f.http.is_none() && f.mock_response.is_none() {
213                let call_config = e2e_config.resolve_call_for_fixture(f.call.as_deref(), &f.input);
214                let fn_name = resolve_function_name_for_call(call_config);
215                return !fn_name.is_empty();
216            }
217            false
218        }) {
219            let call_config = e2e_config.resolve_call_for_fixture(fixture.call.as_deref(), &fixture.input);
220            for arg in &call_config.args {
221                if arg.arg_type == "json_object" {
222                    if let Some(ref elem_type) = arg.element_type {
223                        element_types.insert(elem_type.clone());
224                    }
225                }
226            }
227        }
228        for elem_type in &element_types {
229            let _ = writeln!(out, "use {module}::{elem_type};");
230        }
231    }
232
233    let _ = writeln!(out);
234
235    for fixture in fixtures {
236        render_test_function(&mut out, fixture, e2e_config, dep_name, &field_resolver, client_factory);
237        let _ = writeln!(out);
238    }
239
240    if !out.ends_with('\n') {
241        out.push('\n');
242    }
243    out
244}
245
246pub fn render_test_function(
247    out: &mut String,
248    fixture: &Fixture,
249    e2e_config: &E2eConfig,
250    dep_name: &str,
251    field_resolver: &FieldResolver,
252    client_factory: Option<&str>,
253) {
254    // Http fixtures get their own integration test code path.
255    if fixture.http.is_some() {
256        render_http_test_function(out, fixture, dep_name);
257        return;
258    }
259
260    // Fixtures that have neither `http` nor `mock_response` may be either:
261    //  - schema/spec validation fixtures (asyncapi, grpc, graphql_schema, …) with no callable
262    //    function → emit a TODO stub so the suite compiles and preserves test count.
263    //  - plain function-call fixtures (e.g. kreuzberg::extract_file) with a configured
264    //    `[e2e.call]` → fall through to the real function-call code path below.
265    if fixture.http.is_none() && fixture.mock_response.is_none() {
266        let call_config = e2e_config.resolve_call_for_fixture(fixture.call.as_deref(), &fixture.input);
267        let resolved_fn_name = resolve_function_name_for_call(call_config);
268        if resolved_fn_name.is_empty() {
269            let fn_name = crate::escape::sanitize_ident(&fixture.id);
270            let description = &fixture.description;
271            let _ = writeln!(out, "#[tokio::test]");
272            let _ = writeln!(out, "async fn test_{fn_name}() {{");
273            let _ = writeln!(out, "    // {description}");
274            let _ = writeln!(
275                out,
276                "    // TODO: implement when a callable API is available for this fixture type."
277            );
278            let _ = writeln!(out, "}}");
279            return;
280        }
281        // Non-empty function name: fall through to emit a real function call below.
282    }
283
284    let fn_name = crate::escape::sanitize_ident(&fixture.id);
285    let description = &fixture.description;
286    let call_config = e2e_config.resolve_call_for_fixture(fixture.call.as_deref(), &fixture.input);
287    let function_name = resolve_function_name_for_call(call_config);
288    let module = resolve_module_for_call(call_config, dep_name);
289    let result_var = &call_config.result_var;
290    let has_mock = fixture.mock_response.is_some();
291
292    // Resolve Rust-specific overrides early since we need them for returns_result.
293    let rust_overrides = call_config.overrides.get("rust");
294
295    // Determine if this call returns Result<T, E>. Per-rust override takes precedence.
296    // When client_factory is set, methods always return Result<T>.
297    let returns_result = rust_overrides
298        .and_then(|o| o.returns_result)
299        .unwrap_or(if client_factory.is_some() {
300            true
301        } else {
302            call_config.returns_result
303        });
304
305    // Tests with a mock server are always async (Axum requires a Tokio runtime).
306    let is_async = call_config.r#async || has_mock;
307    if is_async {
308        let _ = writeln!(out, "#[tokio::test]");
309        let _ = writeln!(out, "async fn test_{fn_name}() {{");
310    } else {
311        let _ = writeln!(out, "#[test]");
312        let _ = writeln!(out, "fn test_{fn_name}() {{");
313    }
314    let _ = writeln!(out, "    // {description}");
315
316    // Emit mock server setup before building arguments so arg expressions can
317    // reference `mock_server.url` when needed.
318    if has_mock {
319        render_mock_server_setup(out, fixture, e2e_config);
320    }
321
322    // Check if any assertion is an error assertion.
323    let has_error_assertion = fixture.assertions.iter().any(|a| a.assertion_type == "error");
324
325    // Extract additional overrides for argument shaping.
326    let wrap_options_in_some = rust_overrides.is_some_and(|o| o.wrap_options_in_some);
327    let extra_args: Vec<String> = rust_overrides.map(|o| o.extra_args.clone()).unwrap_or_default();
328    // options_type from the rust override (e.g. "ConversionOptions") — used to annotate
329    // `Default::default()` and `serde_json::from_value(…)` bindings so Rust can infer
330    // the concrete type without a trailing positional argument to guide inference.
331    let options_type: Option<String> = rust_overrides.and_then(|o| o.options_type.clone());
332
333    // When the fixture declares a visitor that is passed via an options-field (the
334    // html-to-markdown core `convert` API accepts visitor only through
335    // `ConversionOptions.visitor`), the options binding must be `mut` so we can
336    // assign the visitor field before the call.
337    let visitor_via_options = fixture.visitor.is_some() && rust_overrides.is_none_or(|o| o.visitor_function.is_none());
338
339    // Emit input variable bindings from args config.
340    let mut arg_exprs: Vec<String> = Vec::new();
341    // Track the name of the json_object options arg so we can inject the visitor later.
342    let mut options_arg_name: Option<String> = None;
343    for arg in &call_config.args {
344        let value = crate::codegen::resolve_field(&fixture.input, &arg.field);
345        let var_name = &arg.name;
346        let (mut bindings, expr) = render_rust_arg(
347            var_name,
348            value,
349            &arg.arg_type,
350            arg.optional,
351            &module,
352            &fixture.id,
353            if has_mock {
354                Some("mock_server.url.as_str()")
355            } else {
356                None
357            },
358            arg.owned,
359            arg.element_type.as_deref(),
360            &e2e_config.test_documents_dir,
361        );
362        // Add explicit type annotation to json_object bindings so Rust can resolve
363        // `Default::default()` and `serde_json::from_value(…)` without a trailing
364        // positional argument to guide inference.
365        if arg.arg_type == "json_object" {
366            if let Some(ref opts_type) = options_type {
367                bindings = bindings
368                    .into_iter()
369                    .map(|b| {
370                        // `let {name} = …` → `let {name}: {opts_type} = …`
371                        let prefix = format!("let {var_name} = ");
372                        if b.starts_with(&prefix) {
373                            format!("let {var_name}: {opts_type} = {}", &b[prefix.len()..])
374                        } else {
375                            b
376                        }
377                    })
378                    .collect();
379            }
380        }
381        // When the visitor will be injected via the options field, the options binding
382        // must be declared `mut` so we can assign `options.visitor = Some(visitor)`.
383        if visitor_via_options && arg.arg_type == "json_object" {
384            options_arg_name = Some(var_name.clone());
385            bindings = bindings
386                .into_iter()
387                .map(|b| {
388                    // `let {name}` → `let mut {name}`
389                    let prefix = format!("let {var_name}");
390                    if b.starts_with(&prefix) {
391                        format!("let mut {}", &b[4..])
392                    } else {
393                        b
394                    }
395                })
396                .collect();
397        }
398        for binding in &bindings {
399            let _ = writeln!(out, "    {binding}");
400        }
401        // For functions whose options slot is owned `Option<T>` rather than `&T`,
402        // wrap the json_object expression in `Some(...).clone()` so it matches
403        // the parameter shape. Other arg types pass through unchanged.
404        let final_expr = if wrap_options_in_some && arg.arg_type == "json_object" {
405            if visitor_via_options {
406                // Visitor will be injected into options before the call; pass by move
407                // (no .clone() needed).
408                let name = if let Some(rest) = expr.strip_prefix('&') {
409                    rest.to_string()
410                } else {
411                    expr.clone()
412                };
413                format!("Some({name})")
414            } else if let Some(rest) = expr.strip_prefix('&') {
415                format!("Some({rest}.clone())")
416            } else {
417                format!("Some({expr})")
418            }
419        } else {
420            expr
421        };
422        arg_exprs.push(final_expr);
423    }
424
425    // Emit visitor if present in fixture.
426    if let Some(visitor_spec) = &fixture.visitor {
427        // The visitor trait name must be configured via
428        // `[e2e.call.overrides.rust] visitor_trait`; we propagate the error to the caller.
429        let visitor_trait = resolve_visitor_trait(rust_overrides)
430            .expect("visitor_trait must be set in [e2e.call.overrides.rust] when a fixture declares a visitor block");
431        // The visitor trait requires `std::fmt::Debug`; derive it on the inline struct.
432        let _ = writeln!(out, "    #[derive(Debug)]");
433        let _ = writeln!(out, "    struct _TestVisitor;");
434        let _ = writeln!(out, "    impl {visitor_trait} for _TestVisitor {{");
435        for (method_name, action) in &visitor_spec.callbacks {
436            emit_rust_visitor_method(out, method_name, action);
437        }
438        let _ = writeln!(out, "    }}");
439        let _ = writeln!(
440            out,
441            "    let visitor = std::rc::Rc::new(std::cell::RefCell::new(_TestVisitor));"
442        );
443        if visitor_via_options {
444            // Inject the visitor via the options field rather than as a positional arg.
445            let opts_name = options_arg_name.as_deref().unwrap_or("options");
446            let _ = writeln!(out, "    {opts_name}.visitor = Some(visitor);");
447        } else {
448            // Binding uses a visitor_function override that takes visitor as positional arg.
449            arg_exprs.push("Some(visitor)".to_string());
450        }
451    } else {
452        // No fixture-supplied visitor: append any extra positional args declared in
453        // the rust override (e.g. trailing `None` for an Option<VisitorParam> slot).
454        arg_exprs.extend(extra_args);
455    }
456
457    let args_str = arg_exprs.join(", ");
458
459    let await_suffix = if is_async { ".await" } else { "" };
460
461    // When client_factory is configured, emit a `create_client` call and dispatch
462    // methods on the returned client object instead of calling free functions.
463    // The mock server URL (when present) is passed as `base_url`; otherwise `None`.
464    let call_expr = if let Some(factory) = client_factory {
465        let base_url_arg = if has_mock {
466            "Some(mock_server.url.clone())"
467        } else {
468            "None"
469        };
470        let _ = writeln!(
471            out,
472            "    let client = {module}::{factory}(\"test-key\".to_string(), {base_url_arg}, None, None, None).unwrap();"
473        );
474        format!("client.{function_name}({args_str})")
475    } else {
476        format!("{function_name}({args_str})")
477    };
478
479    let result_is_tree = call_config.result_var == "tree";
480    // When the call config or rust override sets result_is_simple, the function
481    // returns a plain type (String, Vec<T>, etc.) — field-access assertions use
482    // the result var directly.
483    let result_is_simple = call_config.result_is_simple || rust_overrides.is_some_and(|o| o.result_is_simple);
484    // When result_is_vec is set, the function returns Vec<T>. Field-path assertions
485    // are wrapped in `.iter().all(|r| ...)` so every element is checked.
486    let result_is_vec = rust_overrides.is_some_and(|o| o.result_is_vec);
487    // When result_is_option is set, the function returns Option<T>. Field-path
488    // assertions unwrap first via `.as_ref().expect("Option should be Some")`.
489    let result_is_option = call_config.result_is_option || rust_overrides.is_some_and(|o| o.result_is_option);
490
491    if has_error_assertion {
492        let _ = writeln!(out, "    let {result_var} = {call_expr}{await_suffix};");
493        // Check if any assertion is NOT an error assertion (i.e., accesses fields on the Ok value).
494        let has_non_error_assertions = fixture
495            .assertions
496            .iter()
497            .any(|a| !matches!(a.assertion_type.as_str(), "error" | "not_error"));
498        // When returns_result=true and there are field assertions (non-error), we need to
499        // handle the Result wrapper: unwrap Ok for field assertions, extract Err for error assertions.
500        if returns_result && has_non_error_assertions {
501            // Emit a temporary binding for the unwrapped Ok value.
502            let _ = writeln!(out, "    let {result_var}_ok = {result_var}.as_ref().ok();");
503        }
504        // Render error assertions.
505        for assertion in &fixture.assertions {
506            render_assertion(
507                out,
508                assertion,
509                result_var,
510                &module,
511                dep_name,
512                true,
513                &[],
514                field_resolver,
515                result_is_tree,
516                result_is_simple,
517                false,
518                false,
519                returns_result,
520            );
521        }
522        let _ = writeln!(out, "}}");
523        return;
524    }
525
526    // Non-error path: unwrap the result.
527    let has_not_error = fixture.assertions.iter().any(|a| a.assertion_type == "not_error");
528
529    // Check if any assertion actually uses the result variable.
530    // If all assertions are skipped (field not on result type), use `_` to avoid
531    // Rust's "variable never used" warning.
532    let has_usable_assertion = fixture.assertions.iter().any(|a| {
533        if a.assertion_type == "not_error" || a.assertion_type == "error" {
534            return false;
535        }
536        if a.assertion_type == "method_result" {
537            // method_result assertions that would generate only a TODO comment don't use the
538            // result variable. These are: missing `method` field, or unsupported `check` type.
539            let supported_checks = [
540                "equals",
541                "is_true",
542                "is_false",
543                "greater_than_or_equal",
544                "count_min",
545                "is_error",
546                "contains",
547                "not_empty",
548                "is_empty",
549            ];
550            let check = a.check.as_deref().unwrap_or("is_true");
551            if a.method.is_none() || !supported_checks.contains(&check) {
552                return false;
553            }
554        }
555        match &a.field {
556            Some(f) if !f.is_empty() => field_resolver.is_valid_for_result(f),
557            _ => true,
558        }
559    });
560
561    let result_binding = if has_usable_assertion {
562        result_var.to_string()
563    } else {
564        "_".to_string()
565    };
566
567    // Detect Option-returning functions: only skip unwrap when ALL assertions are
568    // pure emptiness/bool checks with NO field access (is_none/is_some on the result itself).
569    // If any assertion accesses a field (e.g. `html`), we need the inner value, so unwrap.
570    let has_field_access = fixture
571        .assertions
572        .iter()
573        .any(|a| a.field.as_ref().is_some_and(|f| !f.is_empty()));
574    let only_emptiness_checks = !has_field_access
575        && fixture.assertions.iter().all(|a| {
576            matches!(
577                a.assertion_type.as_str(),
578                "is_empty" | "is_false" | "not_empty" | "is_true" | "not_error"
579            )
580        });
581
582    let unwrap_suffix = if returns_result {
583        ".expect(\"should succeed\")"
584    } else {
585        ""
586    };
587    if !returns_result || (only_emptiness_checks && !has_not_error) {
588        // Option-returning or non-Result-returning (and not a not_error check): bind raw value, no unwrap.
589        // When returns_result=true and has_not_error, fall through to emit .expect() so errors panic.
590        let _ = writeln!(out, "    let {result_binding} = {call_expr}{await_suffix};");
591    } else if has_not_error || !fixture.assertions.is_empty() {
592        let _ = writeln!(
593            out,
594            "    let {result_binding} = {call_expr}{await_suffix}{unwrap_suffix};"
595        );
596    } else {
597        let _ = writeln!(out, "    let {result_binding} = {call_expr}{await_suffix};");
598    }
599
600    // Emit Option field unwrap bindings for any fields accessed in assertions.
601    // Use FieldResolver to handle optional fields, including nested/aliased paths.
602    // Skipped when the call returns Vec<T>: per-element iteration is emitted by
603    // `render_assertion` itself, so the call-site has no single result struct
604    // to unwrap fields off of.
605    let string_assertion_types = [
606        "equals",
607        "contains",
608        "contains_all",
609        "contains_any",
610        "not_contains",
611        "starts_with",
612        "ends_with",
613        "min_length",
614        "max_length",
615        "matches_regex",
616    ];
617    let mut unwrapped_fields: Vec<(String, String)> = Vec::new(); // (fixture_field, local_var)
618    if !result_is_vec {
619        for assertion in &fixture.assertions {
620            if let Some(f) = &assertion.field {
621                if !f.is_empty()
622                    && string_assertion_types.contains(&assertion.assertion_type.as_str())
623                    && !unwrapped_fields.iter().any(|(ff, _)| ff == f)
624                {
625                    // Only unwrap optional string fields — numeric optionals (u64, usize)
626                    // don't support .as_deref() and should be compared directly.
627                    let is_string_assertion = assertion.value.as_ref().is_none_or(|v| v.is_string());
628                    if !is_string_assertion {
629                        continue;
630                    }
631                    if let Some((binding, local_var)) = field_resolver.rust_unwrap_binding(f, result_var) {
632                        let _ = writeln!(out, "    {binding}");
633                        unwrapped_fields.push((f.clone(), local_var));
634                    }
635                }
636            }
637        }
638    }
639
640    // Render assertions.
641    for assertion in &fixture.assertions {
642        if assertion.assertion_type == "not_error" {
643            // Already handled by .expect() above.
644            continue;
645        }
646        render_assertion(
647            out,
648            assertion,
649            result_var,
650            &module,
651            dep_name,
652            false,
653            &unwrapped_fields,
654            field_resolver,
655            result_is_tree,
656            result_is_simple,
657            result_is_vec,
658            result_is_option,
659            returns_result,
660        );
661    }
662
663    let _ = writeln!(out, "}}");
664}
665
666/// Collect test file names for use in build.zig and similar build scripts.
667pub fn collect_test_filenames(groups: &[FixtureGroup]) -> Vec<String> {
668    groups
669        .iter()
670        .filter(|g| !g.fixtures.is_empty())
671        .map(|g| format!("{}_test.rs", sanitize_filename(&g.category)))
672        .collect()
673}
674
675#[cfg(test)]
676mod tests {
677    use super::*;
678
679    #[test]
680    fn resolve_module_for_call_prefers_crate_name_override() {
681        use crate::config::CallConfig;
682        use std::collections::HashMap;
683        let mut overrides = HashMap::new();
684        overrides.insert(
685            "rust".to_string(),
686            crate::config::CallOverride {
687                crate_name: Some("custom_crate".to_string()),
688                module: Some("ignored_module".to_string()),
689                ..Default::default()
690            },
691        );
692        let call = CallConfig {
693            overrides,
694            ..Default::default()
695        };
696        let result = resolve_module_for_call(&call, "dep_name");
697        assert_eq!(result, "custom_crate");
698    }
699}