alef 0.25.37

Opinionated polyglot binding generator for Rust libraries
Documentation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
use crate::core::config::ResolvedCrateConfig;
use crate::core::config::extras::AdapterConfig;
use crate::e2e::config::E2eConfig;
use crate::e2e::escape::escape_java;
use crate::e2e::field_access::FieldResolver;
use crate::e2e::fixture::Fixture;
use heck::{ToLowerCamelCase, ToUpperCamelCase};

use super::args::{JavaArgsContext, build_args_and_setup};
use super::assertions::render_assertion;
use super::http::render_http_test_method;
use super::values::{java_builder_expression, json_to_java};
use super::visitor::{apply_java_visitor_arg, build_java_visitor, java_visitor_binding};

#[allow(clippy::too_many_arguments)]
pub(super) fn render_test_method(
    out: &mut String,
    fixture: &Fixture,
    class_name: &str,
    _function_name: &str,
    _result_var: &str,
    _args: &[crate::e2e::config::ArgMapping],
    options_type: Option<&str>,
    result_is_simple: bool,
    e2e_config: &E2eConfig,
    nested_types: &std::collections::HashMap<String, String>,
    nested_types_optional: bool,
    adapters: &[AdapterConfig],
    config: &ResolvedCrateConfig,
    type_defs: &[crate::core::ir::TypeDef],
) {
    // Delegate HTTP fixtures to the HTTP-specific renderer.
    if let Some(http) = &fixture.http {
        render_http_test_method(out, fixture, http);
        return;
    }

    // Resolve per-fixture call config (supports named calls via fixture.call field).
    // Use resolve_call_for_fixture to support auto-routing via select_when.
    let call_config = e2e_config.resolve_call_for_fixture(
        fixture.call.as_deref(),
        &fixture.id,
        &fixture.resolved_category(),
        &fixture.tags,
        &fixture.input,
    );
    // Per-call field resolver: overrides the category-level resolver when this call
    // declares its own result_fields / fields / fields_optional / fields_array.
    let call_field_resolver = FieldResolver::new(
        e2e_config.effective_fields(call_config),
        e2e_config.effective_fields_optional(call_config),
        e2e_config.effective_result_fields(call_config),
        e2e_config.effective_fields_array(call_config),
        &std::collections::HashSet::new(),
    );
    let field_resolver = &call_field_resolver;
    let effective_enum_fields = e2e_config.effective_fields_enum(call_config);
    let enum_fields = effective_enum_fields;
    let lang = "java";
    let call_overrides = call_config.overrides.get(lang);
    let effective_function_name = call_overrides
        .and_then(|o| o.function.as_ref())
        .cloned()
        .unwrap_or_else(|| call_config.function.to_lower_camel_case());
    let effective_result_var = &call_config.result_var;
    let function_name = effective_function_name.as_str();
    let result_var = effective_result_var.as_str();
    let recipe = crate::e2e::codegen::recipe::ResolvedE2eCallRecipe::resolve(lang, fixture, call_config, type_defs);
    let args: &[crate::e2e::config::ArgMapping] = recipe.args;

    let method_name = fixture.id.to_upper_camel_case();
    let description = &fixture.description;
    let expects_error = fixture.assertions.iter().any(|a| a.assertion_type == "error");

    // Resolve per-fixture options_type: prefer the java call override, fall back to
    // class-level, then to any other language's options_type for the same call (the
    // generated Java POJO class name matches the Rust type name across bindings, so
    // mirroring the C/csharp/go option lets us auto-emit `Type.fromJson(json)` without
    // requiring an explicit Java override per call).
    let effective_options_type: Option<String> = recipe
        .options_type
        .map(str::to_string)
        .or_else(|| options_type.map(str::to_string))
        .or_else(|| {
            recipe
                .compatible_options_type(&["csharp", "c", "go", "php", "python"])
                .map(str::to_string)
        });
    let effective_options_type = effective_options_type.as_deref();
    // When options_type is resolvable but no explicit options_via is given for Java,
    // default to "from_json" so the typed-request arg is emitted as
    // `Type.fromJson(json)` rather than the raw JSON string. The Java backend exposes
    // a static `fromJson(String)` factory on every record type (Stage A).
    let auto_from_json = effective_options_type.is_some()
        && call_overrides.and_then(|o| o.options_via.as_deref()).is_none()
        && e2e_config
            .call
            .overrides
            .get(lang)
            .and_then(|o| o.options_via.as_deref())
            .is_none();

    // Resolve client_factory: prefer call-level java override, fall back to file-level java override.
    let client_factory: Option<String> = call_overrides.and_then(|o| o.client_factory.clone()).or_else(|| {
        e2e_config
            .call
            .overrides
            .get(lang)
            .and_then(|o| o.client_factory.clone())
    });

    // Resolve options_via: "kwargs" (default), "from_json", "json", "dict".
    // Auto-default to "from_json" when an options_type is resolvable and no explicit
    // options_via is configured — this lets typed-request args emit `Type.fromJson(json)`
    // even when alef.toml only declares the type in another binding's override block.
    let options_via: String = call_overrides
        .and_then(|o| o.options_via.clone())
        .or_else(|| e2e_config.call.overrides.get(lang).and_then(|o| o.options_via.clone()))
        .unwrap_or_else(|| {
            if auto_from_json {
                "from_json".to_string()
            } else {
                "kwargs".to_string()
            }
        });

    // Resolve per-fixture result_is_simple and result_is_bytes from the call override.
    let effective_result_is_simple =
        call_overrides.is_some_and(|o| o.result_is_simple) || call_config.result_is_simple || result_is_simple;
    let effective_result_is_bytes = call_overrides.is_some_and(|o| o.result_is_bytes);
    // Resolve result_is_option: when the Rust function returns `Option<T>`, the Java
    // facade typically returns `@Nullable T` (via `.orElse(null)`).  Bare-result
    // is_empty/not_empty assertions must use `assertNull/assertNotNull` rather than
    // calling `.isEmpty()` on the nullable reference, which is undefined for record
    // types (mirrors the Kotlin / Zig codegen behaviour).
    let effective_result_is_option = call_overrides.is_some_and(|o| o.result_is_option) || call_config.result_is_option;

    // Check if this test needs ObjectMapper deserialization for json_object args.
    let needs_deser = effective_options_type.is_some()
        && args.iter().any(|arg| {
            if arg.arg_type != "json_object" {
                return false;
            }
            let val = super::super::resolve_field(&fixture.input, &arg.field);
            !val.is_null() && !val.is_array()
        });

    // Emit builder expressions for json_object args.
    let mut builder_expressions = String::new();
    if let (true, Some(opts_type)) = (needs_deser, effective_options_type) {
        for arg in args {
            if arg.arg_type == "json_object" {
                let val = super::super::resolve_field(&fixture.input, &arg.field);
                if !val.is_null() && !val.is_array() {
                    if options_via == "from_json" {
                        // Build the typed POJO via `JsonUtil.fromJson(json, Type.class)`.
                        // The Java backend centralizes JSON deserialization in JsonUtil rather
                        // than per-DTO static methods.  Java uses snake_case wire format
                        // (matches Rust's serde default), so pass through fixture keys as-is.
                        let normalized = super::super::transform_json_keys_for_language(val, "snake_case");
                        let json_str = serde_json::to_string(&normalized).unwrap_or_default();
                        let escaped = escape_java(&json_str);
                        let var_name = &arg.name;
                        builder_expressions.push_str(&format!(
                            "        var {var_name} = JsonUtil.fromJson(\"{escaped}\", {opts_type}.class);\n",
                        ));
                    } else if let Some(obj) = val.as_object() {
                        // Generate builder expression: TypeName.builder().withFieldName(value)...build()
                        let empty_path_fields: Vec<String> = Vec::new();
                        let path_fields = call_overrides.map(|o| &o.path_fields).unwrap_or(&empty_path_fields);
                        let builder_expr = java_builder_expression(
                            obj,
                            opts_type,
                            enum_fields,
                            nested_types,
                            nested_types_optional,
                            path_fields,
                        );
                        let var_name = &arg.name;
                        builder_expressions.push_str(&format!("        var {} = {};\n", var_name, builder_expr));
                    }
                }
            }
        }
    }

    let adapter = adapters.iter().find(|a| a.name == call_config.function.as_str());
    let adapter_request_type: Option<String> = adapter
        .and_then(|a| a.request_type.as_deref())
        .map(|rt| rt.rsplit("::").next().unwrap_or(rt).to_string());

    // Determine if this is a streaming adapter.
    let is_streaming_adapter =
        adapter.is_some_and(|a| matches!(a.pattern, crate::core::config::extras::AdapterPattern::Streaming));

    // When a non-streaming adapter with owner_type is present, filter out handle-type args
    // since the facade method doesn't take them separately (the handle is
    // encapsulated in the adapter).
    let filtered_args: Vec<_> = if adapter.is_some_and(|a| a.owner_type.is_some()) && !is_streaming_adapter {
        args.iter().filter(|arg| arg.arg_type != "handle").cloned().collect()
    } else {
        args.to_vec()
    };

    // Streaming owner_type adapters are facade-exposed as INSTANCE methods on the
    // owner handle (`engine.streamItems(req)`), not as static facade methods — the
    // Java facade deliberately emits no static streaming methods. Capture the owner
    // handle variable so the call is rendered as an instance-method invocation.
    let streaming_owner_handle: Option<String> =
        if is_streaming_adapter && adapter.is_some_and(|a| a.owner_type.is_some()) {
            filtered_args
                .iter()
                .find(|a| a.arg_type == "handle")
                .map(|a| a.name.clone())
        } else {
            None
        };

    let mut teardown_block = String::new();
    let (mut setup_lines, args_str) = build_args_and_setup(
        &fixture.input,
        &filtered_args,
        JavaArgsContext {
            class_name,
            options_type: effective_options_type,
            fixture,
            adapter_request_type: adapter_request_type.as_deref(),
            owner_handle_is_receiver: streaming_owner_handle.is_some(),
            config,
            type_defs,
            teardown_block: &mut teardown_block,
        },
    );

    // Per-language `extra_args` from call overrides — verbatim trailing
    // expressions appended after the configured args (e.g. `null` for an
    // optional trailing parameter the fixture cannot supply). Mirrors the
    // TypeScript and C# implementations.
    let extra_args_slice: &[String] = recipe.extra_args;

    let mut final_args = args_str;
    if let Some(visitor_spec) = &fixture.visitor {
        if let Some(binding) = java_visitor_binding(config, type_defs, Some(visitor_spec), effective_options_type) {
            // Generic discriminated-union result types are supported by the Jinja
            // template via the same factory shape as the default fallback type —
            // drop the historical bail-out and let the generated code compile or
            // surface a clear method-arity diagnostic from the host project's
            // binding.
            let visitor_var = build_java_visitor(&mut setup_lines, visitor_spec, class_name, &binding);
            final_args = apply_java_visitor_arg(&mut setup_lines, &final_args, args, &visitor_var, &binding);
        } else {
            setup_lines.push(format!(
                "org.junit.jupiter.api.Assumptions.assumeTrue(false, \"java visitor fixture '{}' requires trait_bridge options_type, options_field, context_type, and result_type metadata\");",
                escape_java(&fixture.id)
            ));
        }
    }

    if !extra_args_slice.is_empty() {
        let extra_str = extra_args_slice.join(", ");
        final_args = if final_args.is_empty() {
            extra_str
        } else {
            format!("{final_args}, {extra_str}")
        };
    }

    // Render assertions_body
    let mut assertions_body = String::new();

    // Emit a `source` variable for run_query assertions that need the raw bytes.
    let needs_source_var = fixture
        .assertions
        .iter()
        .any(|a| a.assertion_type == "method_result" && a.method.as_deref() == Some("run_query"));
    if needs_source_var {
        if let Some(source_arg) = args.iter().find(|a| a.field == "source_code") {
            let field = source_arg.field.strip_prefix("input.").unwrap_or(&source_arg.field);
            if let Some(val) = fixture.input.get(field) {
                let java_val = json_to_java(val);
                assertions_body.push_str(&format!("        var source = {}.getBytes();\n", java_val));
            }
        }
    }

    // Merge per-call java enum_fields with the file-level java enum_fields so that
    // call-specific enum-typed result fields (e.g. `choices[0].finish_reason` for
    // chat) trigger Optional<Enum> coercion even when the global override block
    // does not list them. Per-call entries take precedence.
    // For assertions, use assert_enum_fields from the call override to get field->type mappings.
    // Build a HashMap that merges both for assertion handling.
    let assert_enum_types: std::collections::HashMap<String, String> = if let Some(co) = call_overrides {
        co.assert_enum_fields.clone()
    } else {
        std::collections::HashMap::new()
    };

    // Keep the old effective_enum_fields as a HashSet for backward compatibility with other code paths.
    let mut effective_enum_fields: std::collections::HashSet<String> = enum_fields.clone();
    if let Some(co) = call_overrides {
        for k in co.enum_fields.keys() {
            effective_enum_fields.insert(k.clone());
        }
    }

    // Streaming detection (call-level `streaming` opt-out is honored). Computed
    // here so `render_assertion` can suppress the streaming-virtual-field path
    // for non-streaming fixtures whose real result struct has a literal `chunks`
    // field that would otherwise collide with the virtual aggregator name.
    let is_streaming =
        crate::e2e::codegen::streaming_assertions::resolve_is_streaming(fixture, call_config.streaming_enabled());
    let streaming_item_type =
        crate::e2e::codegen::recipe::streaming_item_type(call_config, adapters, &[call_config.function.as_str()]);

    for assertion in &fixture.assertions {
        render_assertion(
            &mut assertions_body,
            assertion,
            result_var,
            class_name,
            field_resolver,
            effective_result_is_simple,
            effective_result_is_bytes,
            effective_result_is_option,
            is_streaming,
            streaming_item_type,
            &effective_enum_fields,
            &assert_enum_types,
        );
    }

    let throws_clause = " throws Exception";

    // When client_factory is set, instantiate a client and dispatch the call as
    // a method on the client; otherwise call the static helper on `class_name`.
    let (client_setup_lines, call_target) = if let Some(factory) = client_factory.as_deref() {
        let factory_name = factory.to_lower_camel_case();
        let fixture_id = &fixture.id;
        let mut setup: Vec<String> = Vec::new();
        let has_mock = fixture.mock_response.is_some() || fixture.http.is_some();
        let api_key_var = fixture.env.as_ref().and_then(|e| e.api_key_var.as_deref());
        if let Some(var) = api_key_var.filter(|_| has_mock) {
            setup.push(format!("String apiKey = System.getenv(\"{var}\");"));
            setup.push(format!(
                "String mockServerUrl = System.getProperty(\"mockServerUrl\"); if (mockServerUrl == null) {{ mockServerUrl = System.getenv(\"MOCK_SERVER_URL\"); }} String baseUrl = (apiKey != null && !apiKey.isEmpty()) ? null : (mockServerUrl != null ? mockServerUrl + \"/fixtures/{fixture_id}\" : \"http://localhost:8000/fixtures/{fixture_id}\");"
            ));
            setup.push(format!(
                "System.out.println(\"{fixture_id}: \" + (baseUrl == null ? \"using real API ({var} is set)\" : \"using mock server ({var} not set)\"));"
            ));
            setup.push(format!(
                "var client = {class_name}.{factory_name}(baseUrl == null ? apiKey : \"test-key\", baseUrl, null, null, null);"
            ));
        } else if has_mock {
            if fixture.has_host_root_route() {
                setup.push(format!(
                    "String mockServerUrl = System.getProperty(\"mockServerUrl\"); if (mockServerUrl == null) {{ mockServerUrl = System.getenv(\"MOCK_SERVER_URL\"); }} String defaultUrl = (mockServerUrl != null ? mockServerUrl : \"http://localhost:8000\") + \"/fixtures/{fixture_id}\"; String mockUrl = System.getProperty(\"mockServer.{fixture_id}\", defaultUrl);"
                ));
            } else {
                setup.push(format!(
                    "String mockServerUrl = System.getProperty(\"mockServerUrl\"); if (mockServerUrl == null) {{ mockServerUrl = System.getenv(\"MOCK_SERVER_URL\"); }} String mockUrl = (mockServerUrl != null ? mockServerUrl : \"http://localhost:8000\") + \"/fixtures/{fixture_id}\";"
                ));
            }
            setup.push(format!(
                "var client = {class_name}.{factory_name}(\"test-key\", mockUrl, null, null, null);"
            ));
        } else if let Some(api_key_var) = api_key_var {
            setup.push(format!("String apiKey = System.getenv(\"{api_key_var}\");"));
            setup.push(format!(
                "org.junit.jupiter.api.Assumptions.assumeTrue(apiKey != null && !apiKey.isEmpty(), \"{api_key_var} not set\");"
            ));
            setup.push(format!("var client = {class_name}.{factory_name}(apiKey);"));
        } else {
            setup.push(format!("var client = {class_name}.{factory_name}(\"test-key\");"));
        }
        (setup, "client".to_string())
    } else {
        (Vec::new(), class_name.to_string())
    };

    // Prepend client setup before any other setup_lines.
    let combined_setup: Vec<String> = client_setup_lines.into_iter().chain(setup_lines).collect();

    let call_expr = if let Some(ref handle_var) = streaming_owner_handle {
        // Instance-method invocation on the owner handle.
        format!("{handle_var}.{function_name}({final_args})")
    } else {
        format!("{call_target}.{function_name}({final_args})")
    };

    // `is_streaming` was computed earlier (before the assertion render loop).
    let collect_snippet = if is_streaming && !expects_error {
        // Derive the item_type from the adapter if present; otherwise use the default.
        crate::e2e::codegen::streaming_assertions::StreamingFieldResolver::collect_snippet_typed(
            "java",
            result_var,
            "chunks",
            streaming_item_type,
        )
        .unwrap_or_default()
    } else {
        String::new()
    };

    let rendered = crate::e2e::template_env::render(
        "java/test_method.jinja",
        minijinja::context! {
            method_name => method_name,
            description => description,
            builder_expressions => builder_expressions,
            setup_lines => combined_setup,
            throws_clause => throws_clause,
            expects_error => expects_error,
            call_expr => call_expr,
            result_var => result_var,
            returns_void => call_config.returns_void,
            collect_snippet => collect_snippet,
            assertions_body => assertions_body,
            teardown_block => teardown_block,
        },
    );
    out.push_str(&rendered);
}