tarn 0.11.4

CLI-first API testing tool
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
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
//! LLM-friendly output format (NAZ-349).
//!
//! Designed to be piped into an AI assistant or into `grep`:
//!
//! * A single grep-friendly first line (`tarn: PASS 498/500 steps, ...`).
//! * No per-file running output, no boxed headers, no colors when
//!   stdout isn't a TTY (the caller passes `no_color: true` in that
//!   case).
//! * Only failures are expanded; each block is short and stable.
//!
//! The format shares helpers with the compact format via
//! `super::failure`, so any future change to request/response/summary
//! shape lands in both at once.

use crate::assert::types::{FailureCategory, FileResult, RunResult, StepResult};
use crate::model::RedactionConfig;
use crate::report::failure::{
    for_each_step, format_assertion_line, group_failures, request_line, response_body_preview,
    skip_cascade_summary, LLM_BODY_PREVIEW_CHARS,
};
use crate::report::redaction::sanitize_assertion;
use crate::report::RenderOptions;

/// Render with default options (no filtering, no color override).
pub fn render(result: &RunResult) -> String {
    render_with_options(result, RenderOptions::default())
}

/// Render respecting the caller's options. `only_failed` drops passing
/// files from the grep summary line (they are already implicit in the
/// pass/fail count); LLM format never expands passing steps so the
/// other knobs are mostly inherited from `compact`.
pub fn render_with_options(result: &RunResult, _opts: RenderOptions) -> String {
    let mut out = String::new();
    out.push_str(&render_summary_line(result));
    out.push('\n');

    // Stable file ordering. Source order within a file is already
    // preserved by the runner, but we sort files alphabetically so two
    // runs with parallel file scheduling still emit the same text.
    let mut files: Vec<&FileResult> = result.file_results.iter().collect();
    files.sort_by(|a, b| a.file.cmp(&b.file));

    for file in files {
        render_file_failures(&mut out, file);
    }

    let groups = group_failures(result);
    if !groups.is_empty() {
        out.push('\n');
        out.push_str("failure summary:\n");
        for (label, count) in &groups {
            out.push_str(&format!("  {}: {}\n", label, count));
        }
    }
    out
}

/// Render the one-line grep-friendly summary. The exact format is a
/// stable contract with LLM consumers — do not change the prefix,
/// separators, or ordering without bumping the documentation.
pub fn render_summary_line(result: &RunResult) -> String {
    let passed = result.passed_steps();
    let total = result.total_steps();
    let failed = result.failed_steps();
    let files = result.total_files();
    let seconds = format!("{:.1}", result.duration_ms as f64 / 1000.0);
    let status = if result.passed() { "PASS" } else { "FAIL" };
    format!(
        "tarn: {} {}/{} steps, {} failed, {} file{}, {}s",
        status,
        passed,
        total,
        failed,
        files,
        if files == 1 { "" } else { "s" },
        seconds
    )
}

fn render_file_failures(out: &mut String, file: &FileResult) {
    // Walk every step in source order so the output is deterministic.
    for_each_step(file, &mut |test, is_teardown, step| {
        if step.passed {
            return;
        }
        let phase = if test.is_some() {
            None
        } else if is_teardown {
            Some("teardown")
        } else {
            Some("setup")
        };
        render_failure_block(out, file, test.map(|t| t.name.as_str()), phase, step);
    });

    // Cascade summaries are emitted per-test once so readers can see how
    // many steps were suppressed without scrolling through every one.
    for test in &file.test_results {
        for (capture, count) in skip_cascade_summary(test) {
            out.push_str(&format!(
                "skipped: {} step{} (depended on failed capture '{}') in {}::{}\n",
                count,
                if count == 1 { "" } else { "s" },
                capture,
                file.file,
                test.name
            ));
        }
    }
}

fn render_failure_block(
    out: &mut String,
    file: &FileResult,
    test_name: Option<&str>,
    phase: Option<&str>,
    step: &StepResult,
) {
    let label = match (test_name, phase) {
        (Some(name), _) => format!("{}::{}::{}", file.file, name, step.name),
        (None, Some(phase)) => format!("{}::<{}>::{}", file.file, phase, step.name),
        (None, None) => format!("{}::{}", file.file, step.name),
    };

    // Cascade skips use a distinct tag so downstream tools can filter
    // fallout from primary failures without parsing the message body.
    let tag = if matches!(
        step.error_category,
        Some(FailureCategory::SkippedDueToFailedCapture)
            | Some(FailureCategory::SkippedDueToFailFast)
    ) {
        "SKIP"
    } else {
        "FAIL"
    };

    out.push_str(&format!("{} {}\n", tag, label));
    render_request(out, step, &file.redaction, &file.redacted_values);
    render_response(out, step, &file.redaction, &file.redacted_values);
    render_asserts(out, step, &file.redaction, &file.redacted_values);
    render_captures(out, step, &file.redaction, &file.redacted_values);
    out.push('\n');
}

fn render_request(
    out: &mut String,
    step: &StepResult,
    redaction: &RedactionConfig,
    secrets: &[String],
) {
    if step.request_info.is_none() {
        return;
    }
    out.push_str(&format!(
        "  request:  {}\n",
        request_line(step, redaction, secrets)
    ));
}

fn render_response(
    out: &mut String,
    step: &StepResult,
    redaction: &RedactionConfig,
    secrets: &[String],
) {
    let Some(resp) = step.response_info.as_ref() else {
        if let Some(status) = step.response_status {
            out.push_str(&format!("  response: {}\n", status));
        }
        return;
    };
    out.push_str(&format!("  response: {}\n", resp.status));
    if let Some(preview) = response_body_preview(step, redaction, secrets, LLM_BODY_PREVIEW_CHARS) {
        out.push_str(&format!("    {}\n", preview));
    }
}

fn render_asserts(
    out: &mut String,
    step: &StepResult,
    redaction: &RedactionConfig,
    secrets: &[String],
) {
    for assertion in step.assertion_results.iter().filter(|a| !a.passed) {
        // Cascade/skip steps manufacture a single informational
        // assertion; surface the message verbatim instead of shoehorning
        // it into the "expected/got" shape.
        if matches!(
            step.error_category,
            Some(FailureCategory::SkippedDueToFailedCapture)
                | Some(FailureCategory::SkippedDueToFailFast)
        ) {
            let sanitized = sanitize_assertion(assertion, redaction, secrets);
            out.push_str(&format!("  reason:   {}\n", sanitized.message));
            continue;
        }
        out.push_str(&format!(
            "  assert:   {}\n",
            format_assertion_line(assertion, redaction, secrets)
        ));
    }
}

fn render_captures(
    out: &mut String,
    step: &StepResult,
    _redaction: &RedactionConfig,
    _secrets: &[String],
) {
    if step.captures_set.is_empty() {
        return;
    }
    let mut names = step.captures_set.clone();
    names.sort();
    out.push_str(&format!("  captures: {}\n", names.join(", ")));
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::assert::types::*;
    use crate::model::RedactionConfig;
    use serde_json::json;
    use std::collections::HashMap;

    fn failing_run() -> RunResult {
        RunResult {
            duration_ms: 16300,
            file_results: vec![FileResult {
                file: "tests/users.tarn.yaml".into(),
                name: "users".into(),
                passed: false,
                duration_ms: 16300,
                redaction: RedactionConfig::default(),
                redacted_values: vec![],
                setup_results: vec![],
                test_results: vec![TestResult {
                    name: "create_user".into(),
                    description: None,
                    passed: false,
                    duration_ms: 16300,
                    step_results: vec![StepResult {
                        name: "Create".into(),
                        description: None,
                        debug: false,
                        passed: false,
                        duration_ms: 100,
                        assertion_results: vec![AssertionResult::fail(
                            "status",
                            "200",
                            "500",
                            "Expected 200, got 500",
                        )],
                        request_info: Some(RequestInfo {
                            method: "POST".into(),
                            url: "/v1/api/users".into(),
                            headers: HashMap::from([(
                                "Authorization".into(),
                                "Bearer secret".into(),
                            )]),
                            body: None,
                            multipart: None,
                        }),
                        response_info: Some(ResponseInfo {
                            status: 500,
                            headers: HashMap::new(),
                            body: Some(json!({"message": "boom"})),
                        }),
                        error_category: Some(FailureCategory::AssertionFailed),
                        response_status: Some(500),
                        response_summary: None,
                        captures_set: vec!["id".into()],
                        location: None,
                        response_shape_mismatch: None,
                    }],
                    captures: HashMap::new(),
                }],
                teardown_results: vec![],
            }],
        }
    }

    #[test]
    fn first_line_is_grep_friendly() {
        let out = render(&failing_run());
        let first = out.lines().next().unwrap();
        assert!(first.starts_with("tarn: FAIL 0/1 steps, 1 failed, 1 file,"));
    }

    #[test]
    fn passing_run_reports_pass_status() {
        let run = RunResult {
            duration_ms: 120,
            file_results: vec![FileResult {
                file: "a.tarn.yaml".into(),
                name: "a".into(),
                passed: true,
                duration_ms: 120,
                redaction: RedactionConfig::default(),
                redacted_values: vec![],
                setup_results: vec![],
                test_results: vec![TestResult {
                    name: "t".into(),
                    description: None,
                    passed: true,
                    duration_ms: 120,
                    step_results: vec![StepResult {
                        name: "ok".into(),
                        description: None,
                        debug: false,
                        passed: true,
                        duration_ms: 120,
                        assertion_results: vec![AssertionResult::pass("status", "200", "200")],
                        request_info: None,
                        response_info: None,
                        error_category: None,
                        response_status: Some(200),
                        response_summary: None,
                        captures_set: vec![],
                        location: None,
                        response_shape_mismatch: None,
                    }],
                    captures: HashMap::new(),
                }],
                teardown_results: vec![],
            }],
        };
        let out = render(&run);
        assert!(out.lines().next().unwrap().starts_with("tarn: PASS 1/1"));
        assert!(!out.contains("FAIL "));
    }

    #[test]
    fn failure_block_includes_request_response_assert() {
        let out = render(&failing_run());
        assert!(out.contains("FAIL tests/users.tarn.yaml::create_user::Create"));
        assert!(out.contains("request:  POST /v1/api/users (Authorization: ***)"));
        assert!(out.contains("response: 500"));
        assert!(out.contains("\"message\":\"boom\""));
        assert!(out.contains("assert:   status: expected 200, got 500"));
    }

    #[test]
    fn failure_summary_appears_at_end() {
        let out = render(&failing_run());
        assert!(out.contains("failure summary:"));
        assert!(out.contains("HTTP 500: 1"));
    }

    #[test]
    fn files_render_in_sorted_order() {
        let mut run = failing_run();
        run.file_results.push(FileResult {
            file: "tests/aaa.tarn.yaml".into(),
            name: "aaa".into(),
            passed: false,
            duration_ms: 10,
            redaction: RedactionConfig::default(),
            redacted_values: vec![],
            setup_results: vec![],
            test_results: vec![TestResult {
                name: "t".into(),
                description: None,
                passed: false,
                duration_ms: 10,
                step_results: vec![StepResult {
                    name: "s".into(),
                    description: None,
                    debug: false,
                    passed: false,
                    duration_ms: 10,
                    assertion_results: vec![AssertionResult::fail(
                        "status",
                        "200",
                        "404",
                        "Expected 200, got 404",
                    )],
                    request_info: Some(RequestInfo {
                        method: "GET".into(),
                        url: "/x".into(),
                        headers: HashMap::new(),
                        body: None,
                        multipart: None,
                    }),
                    response_info: None,
                    error_category: Some(FailureCategory::AssertionFailed),
                    response_status: Some(404),
                    response_summary: None,
                    captures_set: vec![],
                    location: None,
                    response_shape_mismatch: None,
                }],
                captures: HashMap::new(),
            }],
            teardown_results: vec![],
        });
        let out = render(&run);
        let pos_aaa = out.find("tests/aaa.tarn.yaml").unwrap();
        let pos_users = out.find("tests/users.tarn.yaml").unwrap();
        assert!(
            pos_aaa < pos_users,
            "alphabetical ordering should render aaa before users"
        );
    }

    #[test]
    fn cascade_skip_emits_single_line_per_capture() {
        let mut run = failing_run();
        run.file_results[0].test_results[0]
            .step_results
            .push(StepResult {
                name: "step_dep_a".into(),
                description: None,
                debug: false,
                passed: false,
                duration_ms: 0,
                assertion_results: vec![AssertionResult::fail(
                    "runtime",
                    "ok",
                    "skipped",
                    "step skipped: depends on capture 'id' which failed",
                )],
                request_info: None,
                response_info: None,
                error_category: Some(FailureCategory::SkippedDueToFailedCapture),
                response_status: None,
                response_summary: None,
                captures_set: vec![],
                location: None,
                response_shape_mismatch: None,
            });
        run.file_results[0].test_results[0]
            .step_results
            .push(StepResult {
                name: "step_dep_b".into(),
                description: None,
                debug: false,
                passed: false,
                duration_ms: 0,
                assertion_results: vec![AssertionResult::fail(
                    "runtime",
                    "ok",
                    "skipped",
                    "step skipped: depends on capture 'id' which failed",
                )],
                request_info: None,
                response_info: None,
                error_category: Some(FailureCategory::SkippedDueToFailedCapture),
                response_status: None,
                response_summary: None,
                captures_set: vec![],
                location: None,
                response_shape_mismatch: None,
            });
        let out = render(&run);
        let expected = "skipped: 2 steps (depended on failed capture 'id') in \
             tests/users.tarn.yaml::create_user";
        assert!(out.contains(expected));
    }

    #[test]
    fn passing_run_has_no_failure_summary() {
        let run = RunResult {
            duration_ms: 10,
            file_results: vec![FileResult {
                file: "a.tarn.yaml".into(),
                name: "a".into(),
                passed: true,
                duration_ms: 10,
                redaction: RedactionConfig::default(),
                redacted_values: vec![],
                setup_results: vec![],
                test_results: vec![],
                teardown_results: vec![],
            }],
        };
        let out = render(&run);
        assert!(!out.contains("failure summary:"));
    }
}