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fallow_cli/report/
mod.rs

1mod badge;
2mod codeclimate;
3mod compact;
4mod human;
5mod json;
6mod markdown;
7mod sarif;
8#[cfg(test)]
9mod test_helpers;
10
11use std::path::Path;
12use std::process::ExitCode;
13use std::time::Duration;
14
15use fallow_config::{OutputFormat, RulesConfig, Severity};
16use fallow_core::duplicates::DuplicationReport;
17use fallow_core::results::AnalysisResults;
18use fallow_core::trace::{CloneTrace, DependencyTrace, ExportTrace, FileTrace, PipelineTimings};
19
20/// Shared context for all report dispatch functions.
21///
22/// Bundles the common parameters that every format renderer needs,
23/// replacing per-parameter threading through the dispatch match arms.
24pub struct ReportContext<'a> {
25    pub root: &'a Path,
26    pub rules: &'a RulesConfig,
27    pub elapsed: Duration,
28    pub quiet: bool,
29    pub explain: bool,
30}
31
32/// Strip the project root prefix from a path for display, falling back to the full path.
33#[must_use]
34pub fn relative_path<'a>(path: &'a Path, root: &Path) -> &'a Path {
35    path.strip_prefix(root).unwrap_or(path)
36}
37
38/// Split a path string into (directory, filename) for display.
39/// Directory includes the trailing `/`. If no directory, returns `("", filename)`.
40#[must_use]
41pub fn split_dir_filename(path: &str) -> (&str, &str) {
42    path.rfind('/')
43        .map_or(("", path), |pos| (&path[..=pos], &path[pos + 1..]))
44}
45
46/// Return `"s"` for plural or `""` for singular.
47#[must_use]
48pub const fn plural(n: usize) -> &'static str {
49    if n == 1 { "" } else { "s" }
50}
51
52/// Serialize a JSON value to pretty-printed stdout, returning the appropriate exit code.
53///
54/// On success prints the JSON and returns `ExitCode::SUCCESS`.
55/// On serialization failure prints an error to stderr and returns exit code 2.
56#[must_use]
57pub fn emit_json(value: &serde_json::Value, kind: &str) -> ExitCode {
58    match serde_json::to_string_pretty(value) {
59        Ok(json) => {
60            println!("{json}");
61            ExitCode::SUCCESS
62        }
63        Err(e) => {
64            eprintln!("Error: failed to serialize {kind} output: {e}");
65            ExitCode::from(2)
66        }
67    }
68}
69
70/// Elide the common directory prefix between a base path and a target path.
71/// Only strips complete directory segments (never partial filenames).
72/// Returns the remaining suffix of `target`.
73///
74/// Example: `elide_common_prefix("a/b/c/foo.ts", "a/b/d/bar.ts")` → `"d/bar.ts"`
75#[must_use]
76pub fn elide_common_prefix<'a>(base: &str, target: &'a str) -> &'a str {
77    let mut last_sep = 0;
78    for (i, (a, b)) in base.bytes().zip(target.bytes()).enumerate() {
79        if a != b {
80            break;
81        }
82        if a == b'/' {
83            last_sep = i + 1;
84        }
85    }
86    if last_sep > 0 && last_sep <= target.len() {
87        &target[last_sep..]
88    } else {
89        target
90    }
91}
92
93/// Compute a SARIF-compatible relative URI from an absolute path and project root.
94fn relative_uri(path: &Path, root: &Path) -> String {
95    normalize_uri(&relative_path(path, root).display().to_string())
96}
97
98/// Normalize a path string to a valid URI: forward slashes and percent-encoded brackets.
99///
100/// Brackets (`[`, `]`) are not valid in URI path segments per RFC 3986 and cause
101/// SARIF validation warnings (e.g., Next.js dynamic routes like `[slug]`).
102#[must_use]
103pub fn normalize_uri(path_str: &str) -> String {
104    path_str
105        .replace('\\', "/")
106        .replace('[', "%5B")
107        .replace(']', "%5D")
108}
109
110/// Severity level for human-readable output.
111#[derive(Clone, Copy, Debug)]
112pub enum Level {
113    Warn,
114    Info,
115    Error,
116}
117
118#[must_use]
119pub const fn severity_to_level(s: Severity) -> Level {
120    match s {
121        Severity::Error => Level::Error,
122        Severity::Warn => Level::Warn,
123        // Off issues are filtered before reporting; fall back to Info.
124        Severity::Off => Level::Info,
125    }
126}
127
128/// Print analysis results in the configured format.
129/// Returns exit code 2 if serialization fails, SUCCESS otherwise.
130///
131/// When `regression` is `Some`, the JSON format includes a `regression` key in the output envelope.
132#[must_use]
133pub fn print_results(
134    results: &AnalysisResults,
135    ctx: &ReportContext<'_>,
136    output: &OutputFormat,
137    regression: Option<&crate::regression::RegressionOutcome>,
138) -> ExitCode {
139    match output {
140        OutputFormat::Human => {
141            human::print_human(results, ctx.root, ctx.rules, ctx.elapsed, ctx.quiet);
142            ExitCode::SUCCESS
143        }
144        OutputFormat::Json => {
145            json::print_json(results, ctx.root, ctx.elapsed, ctx.explain, regression)
146        }
147        OutputFormat::Compact => {
148            compact::print_compact(results, ctx.root);
149            ExitCode::SUCCESS
150        }
151        OutputFormat::Sarif => sarif::print_sarif(results, ctx.root, ctx.rules),
152        OutputFormat::Markdown => {
153            markdown::print_markdown(results, ctx.root);
154            ExitCode::SUCCESS
155        }
156        OutputFormat::CodeClimate => codeclimate::print_codeclimate(results, ctx.root, ctx.rules),
157        OutputFormat::Badge => {
158            eprintln!("Error: badge format is only supported for the health command");
159            ExitCode::from(2)
160        }
161    }
162}
163
164// ── Duplication report ────────────────────────────────────────────
165
166/// Print duplication analysis results in the configured format.
167#[must_use]
168pub fn print_duplication_report(
169    report: &DuplicationReport,
170    ctx: &ReportContext<'_>,
171    output: &OutputFormat,
172) -> ExitCode {
173    match output {
174        OutputFormat::Human => {
175            human::print_duplication_human(report, ctx.root, ctx.elapsed, ctx.quiet);
176            ExitCode::SUCCESS
177        }
178        OutputFormat::Json => json::print_duplication_json(report, ctx.elapsed, ctx.explain),
179        OutputFormat::Compact => {
180            compact::print_duplication_compact(report, ctx.root);
181            ExitCode::SUCCESS
182        }
183        OutputFormat::Sarif => sarif::print_duplication_sarif(report, ctx.root),
184        OutputFormat::Markdown => {
185            markdown::print_duplication_markdown(report, ctx.root);
186            ExitCode::SUCCESS
187        }
188        OutputFormat::CodeClimate => codeclimate::print_duplication_codeclimate(report, ctx.root),
189        OutputFormat::Badge => {
190            eprintln!("Error: badge format is only supported for the health command");
191            ExitCode::from(2)
192        }
193    }
194}
195
196// ── Health / complexity report ─────────────────────────────────────
197
198/// Print health (complexity) analysis results in the configured format.
199#[must_use]
200pub fn print_health_report(
201    report: &crate::health_types::HealthReport,
202    ctx: &ReportContext<'_>,
203    output: &OutputFormat,
204) -> ExitCode {
205    match output {
206        OutputFormat::Human => {
207            human::print_health_human(report, ctx.root, ctx.elapsed, ctx.quiet);
208            ExitCode::SUCCESS
209        }
210        OutputFormat::Compact => {
211            compact::print_health_compact(report, ctx.root);
212            ExitCode::SUCCESS
213        }
214        OutputFormat::Markdown => {
215            markdown::print_health_markdown(report, ctx.root);
216            ExitCode::SUCCESS
217        }
218        OutputFormat::Sarif => sarif::print_health_sarif(report, ctx.root),
219        OutputFormat::Json => json::print_health_json(report, ctx.root, ctx.elapsed, ctx.explain),
220        OutputFormat::CodeClimate => codeclimate::print_health_codeclimate(report, ctx.root),
221        OutputFormat::Badge => badge::print_health_badge(report),
222    }
223}
224
225/// Print cross-reference findings (duplicated code that is also dead code).
226///
227/// Only emits output in human format to avoid corrupting structured JSON/SARIF output.
228pub fn print_cross_reference_findings(
229    cross_ref: &fallow_core::cross_reference::CrossReferenceResult,
230    root: &Path,
231    quiet: bool,
232    output: &OutputFormat,
233) {
234    human::print_cross_reference_findings(cross_ref, root, quiet, output);
235}
236
237// ── Trace output ──────────────────────────────────────────────────
238
239/// Print export trace results.
240pub fn print_export_trace(trace: &ExportTrace, format: &OutputFormat) {
241    match format {
242        OutputFormat::Json => json::print_trace_json(trace),
243        _ => human::print_export_trace_human(trace),
244    }
245}
246
247/// Print file trace results.
248pub fn print_file_trace(trace: &FileTrace, format: &OutputFormat) {
249    match format {
250        OutputFormat::Json => json::print_trace_json(trace),
251        _ => human::print_file_trace_human(trace),
252    }
253}
254
255/// Print dependency trace results.
256pub fn print_dependency_trace(trace: &DependencyTrace, format: &OutputFormat) {
257    match format {
258        OutputFormat::Json => json::print_trace_json(trace),
259        _ => human::print_dependency_trace_human(trace),
260    }
261}
262
263/// Print clone trace results.
264pub fn print_clone_trace(trace: &CloneTrace, root: &Path, format: &OutputFormat) {
265    match format {
266        OutputFormat::Json => json::print_trace_json(trace),
267        _ => human::print_clone_trace_human(trace, root),
268    }
269}
270
271/// Print pipeline performance timings.
272/// In JSON mode, outputs to stderr to avoid polluting the JSON analysis output on stdout.
273pub fn print_performance(timings: &PipelineTimings, format: &OutputFormat) {
274    match format {
275        OutputFormat::Json => match serde_json::to_string_pretty(timings) {
276            Ok(json) => eprintln!("{json}"),
277            Err(e) => eprintln!("Error: failed to serialize timings: {e}"),
278        },
279        _ => human::print_performance_human(timings),
280    }
281}
282
283// Re-exported for snapshot testing via the lib target.
284// Uses #[allow] instead of #[expect] because unused_imports is target-dependent
285// (used in lib target, unused in bin target — #[expect] would be unfulfilled in one).
286#[allow(unused_imports)]
287pub use codeclimate::build_codeclimate;
288#[allow(unused_imports)]
289pub use codeclimate::build_duplication_codeclimate;
290#[allow(unused_imports)]
291pub use codeclimate::build_health_codeclimate;
292#[allow(unused_imports)]
293pub use compact::build_compact_lines;
294#[allow(unused_imports)]
295pub use json::build_json;
296#[allow(unused_imports)]
297pub use markdown::build_duplication_markdown;
298#[allow(unused_imports)]
299pub use markdown::build_health_markdown;
300#[allow(unused_imports)]
301pub use markdown::build_markdown;
302#[allow(unused_imports)]
303pub use sarif::build_health_sarif;
304#[allow(unused_imports)]
305pub use sarif::build_sarif;
306
307#[cfg(test)]
308mod tests {
309    use super::*;
310    use std::path::PathBuf;
311
312    // ── normalize_uri ────────────────────────────────────────────────
313
314    #[test]
315    fn normalize_uri_forward_slashes_unchanged() {
316        assert_eq!(normalize_uri("src/utils.ts"), "src/utils.ts");
317    }
318
319    #[test]
320    fn normalize_uri_backslashes_replaced() {
321        assert_eq!(normalize_uri("src\\utils\\index.ts"), "src/utils/index.ts");
322    }
323
324    #[test]
325    fn normalize_uri_mixed_slashes() {
326        assert_eq!(normalize_uri("src\\utils/index.ts"), "src/utils/index.ts");
327    }
328
329    #[test]
330    fn normalize_uri_path_with_spaces() {
331        assert_eq!(
332            normalize_uri("src\\my folder\\file.ts"),
333            "src/my folder/file.ts"
334        );
335    }
336
337    #[test]
338    fn normalize_uri_empty_string() {
339        assert_eq!(normalize_uri(""), "");
340    }
341
342    // ── relative_path ────────────────────────────────────────────────
343
344    #[test]
345    fn relative_path_strips_root_prefix() {
346        let root = Path::new("/project");
347        let path = Path::new("/project/src/utils.ts");
348        assert_eq!(relative_path(path, root), Path::new("src/utils.ts"));
349    }
350
351    #[test]
352    fn relative_path_returns_full_path_when_no_prefix() {
353        let root = Path::new("/other");
354        let path = Path::new("/project/src/utils.ts");
355        assert_eq!(relative_path(path, root), path);
356    }
357
358    #[test]
359    fn relative_path_at_root_returns_empty_or_file() {
360        let root = Path::new("/project");
361        let path = Path::new("/project/file.ts");
362        assert_eq!(relative_path(path, root), Path::new("file.ts"));
363    }
364
365    #[test]
366    fn relative_path_deeply_nested() {
367        let root = Path::new("/project");
368        let path = Path::new("/project/packages/ui/src/components/Button.tsx");
369        assert_eq!(
370            relative_path(path, root),
371            Path::new("packages/ui/src/components/Button.tsx")
372        );
373    }
374
375    // ── relative_uri ─────────────────────────────────────────────────
376
377    #[test]
378    fn relative_uri_produces_forward_slash_path() {
379        let root = PathBuf::from("/project");
380        let path = root.join("src").join("utils.ts");
381        let uri = relative_uri(&path, &root);
382        assert_eq!(uri, "src/utils.ts");
383    }
384
385    #[test]
386    fn relative_uri_encodes_brackets() {
387        let root = PathBuf::from("/project");
388        let path = root.join("src/app/[...slug]/page.tsx");
389        let uri = relative_uri(&path, &root);
390        assert_eq!(uri, "src/app/%5B...slug%5D/page.tsx");
391    }
392
393    #[test]
394    fn relative_uri_encodes_nested_dynamic_routes() {
395        let root = PathBuf::from("/project");
396        let path = root.join("src/app/[slug]/[id]/page.tsx");
397        let uri = relative_uri(&path, &root);
398        assert_eq!(uri, "src/app/%5Bslug%5D/%5Bid%5D/page.tsx");
399    }
400
401    #[test]
402    fn relative_uri_no_common_prefix_returns_full() {
403        let root = PathBuf::from("/other");
404        let path = PathBuf::from("/project/src/utils.ts");
405        let uri = relative_uri(&path, &root);
406        assert!(uri.contains("project"));
407        assert!(uri.contains("utils.ts"));
408    }
409
410    // ── severity_to_level ────────────────────────────────────────────
411
412    #[test]
413    fn severity_error_maps_to_level_error() {
414        assert!(matches!(severity_to_level(Severity::Error), Level::Error));
415    }
416
417    #[test]
418    fn severity_warn_maps_to_level_warn() {
419        assert!(matches!(severity_to_level(Severity::Warn), Level::Warn));
420    }
421
422    #[test]
423    fn severity_off_maps_to_level_info() {
424        assert!(matches!(severity_to_level(Severity::Off), Level::Info));
425    }
426
427    // ── normalize_uri bracket encoding ──────────────────────────────
428
429    #[test]
430    fn normalize_uri_single_bracket_pair() {
431        assert_eq!(normalize_uri("app/[id]/page.tsx"), "app/%5Bid%5D/page.tsx");
432    }
433
434    #[test]
435    fn normalize_uri_catch_all_route() {
436        assert_eq!(
437            normalize_uri("app/[...slug]/page.tsx"),
438            "app/%5B...slug%5D/page.tsx"
439        );
440    }
441
442    #[test]
443    fn normalize_uri_optional_catch_all_route() {
444        assert_eq!(
445            normalize_uri("app/[[...slug]]/page.tsx"),
446            "app/%5B%5B...slug%5D%5D/page.tsx"
447        );
448    }
449
450    #[test]
451    fn normalize_uri_multiple_dynamic_segments() {
452        assert_eq!(
453            normalize_uri("app/[lang]/posts/[id]"),
454            "app/%5Blang%5D/posts/%5Bid%5D"
455        );
456    }
457
458    #[test]
459    fn normalize_uri_no_special_chars() {
460        let plain = "src/components/Button.tsx";
461        assert_eq!(normalize_uri(plain), plain);
462    }
463
464    #[test]
465    fn normalize_uri_only_backslashes() {
466        assert_eq!(normalize_uri("a\\b\\c"), "a/b/c");
467    }
468
469    // ── relative_path edge cases ────────────────────────────────────
470
471    #[test]
472    fn relative_path_identical_paths_returns_empty() {
473        let root = Path::new("/project");
474        assert_eq!(relative_path(root, root), Path::new(""));
475    }
476
477    #[test]
478    fn relative_path_partial_name_match_not_stripped() {
479        // "/project-two/src/a.ts" should NOT strip "/project" because
480        // "/project" is not a proper prefix of "/project-two".
481        let root = Path::new("/project");
482        let path = Path::new("/project-two/src/a.ts");
483        assert_eq!(relative_path(path, root), path);
484    }
485
486    // ── relative_uri edge cases ─────────────────────────────────────
487
488    #[test]
489    fn relative_uri_combines_stripping_and_encoding() {
490        let root = PathBuf::from("/project");
491        let path = root.join("src/app/[slug]/page.tsx");
492        let uri = relative_uri(&path, &root);
493        // Should both strip the prefix AND encode brackets.
494        assert_eq!(uri, "src/app/%5Bslug%5D/page.tsx");
495        assert!(!uri.starts_with('/'));
496    }
497
498    #[test]
499    fn relative_uri_at_root_file() {
500        let root = PathBuf::from("/project");
501        let path = root.join("index.ts");
502        assert_eq!(relative_uri(&path, &root), "index.ts");
503    }
504
505    // ── severity_to_level exhaustiveness ────────────────────────────
506
507    #[test]
508    fn severity_to_level_is_const_evaluable() {
509        // Verify the function can be used in const context.
510        const LEVEL_FROM_ERROR: Level = severity_to_level(Severity::Error);
511        const LEVEL_FROM_WARN: Level = severity_to_level(Severity::Warn);
512        const LEVEL_FROM_OFF: Level = severity_to_level(Severity::Off);
513        assert!(matches!(LEVEL_FROM_ERROR, Level::Error));
514        assert!(matches!(LEVEL_FROM_WARN, Level::Warn));
515        assert!(matches!(LEVEL_FROM_OFF, Level::Info));
516    }
517
518    // ── Level is Copy ───────────────────────────────────────────────
519
520    #[test]
521    fn level_is_copy() {
522        let level = severity_to_level(Severity::Error);
523        let copy = level;
524        // Both should still be usable (Copy semantics).
525        assert!(matches!(level, Level::Error));
526        assert!(matches!(copy, Level::Error));
527    }
528
529    // ── elide_common_prefix ─────────────────────────────────────────
530
531    #[test]
532    fn elide_common_prefix_shared_dir() {
533        assert_eq!(
534            elide_common_prefix("src/components/A.tsx", "src/components/B.tsx"),
535            "B.tsx"
536        );
537    }
538
539    #[test]
540    fn elide_common_prefix_partial_shared() {
541        assert_eq!(
542            elide_common_prefix("src/components/A.tsx", "src/utils/B.tsx"),
543            "utils/B.tsx"
544        );
545    }
546
547    #[test]
548    fn elide_common_prefix_no_shared() {
549        assert_eq!(
550            elide_common_prefix("pkg-a/src/A.tsx", "pkg-b/src/B.tsx"),
551            "pkg-b/src/B.tsx"
552        );
553    }
554
555    #[test]
556    fn elide_common_prefix_identical_files() {
557        // Same dir, different file
558        assert_eq!(elide_common_prefix("a/b/x.ts", "a/b/y.ts"), "y.ts");
559    }
560
561    #[test]
562    fn elide_common_prefix_no_dirs() {
563        assert_eq!(elide_common_prefix("foo.ts", "bar.ts"), "bar.ts");
564    }
565
566    #[test]
567    fn elide_common_prefix_deep_monorepo() {
568        assert_eq!(
569            elide_common_prefix(
570                "packages/rap/src/rap/components/SearchSelect/SearchSelect.tsx",
571                "packages/rap/src/rap/components/SearchSelect/SearchSelectItem.tsx"
572            ),
573            "SearchSelectItem.tsx"
574        );
575    }
576
577    // ── split_dir_filename ───────────────────────────────────────
578
579    #[test]
580    fn split_dir_filename_with_dir() {
581        let (dir, file) = split_dir_filename("src/utils/index.ts");
582        assert_eq!(dir, "src/utils/");
583        assert_eq!(file, "index.ts");
584    }
585
586    #[test]
587    fn split_dir_filename_no_dir() {
588        let (dir, file) = split_dir_filename("file.ts");
589        assert_eq!(dir, "");
590        assert_eq!(file, "file.ts");
591    }
592
593    #[test]
594    fn split_dir_filename_deeply_nested() {
595        let (dir, file) = split_dir_filename("a/b/c/d/e.ts");
596        assert_eq!(dir, "a/b/c/d/");
597        assert_eq!(file, "e.ts");
598    }
599
600    #[test]
601    fn split_dir_filename_trailing_slash() {
602        let (dir, file) = split_dir_filename("src/");
603        assert_eq!(dir, "src/");
604        assert_eq!(file, "");
605    }
606
607    #[test]
608    fn split_dir_filename_empty() {
609        let (dir, file) = split_dir_filename("");
610        assert_eq!(dir, "");
611        assert_eq!(file, "");
612    }
613
614    // ── plural ──────────────────────────────────────────────────
615
616    #[test]
617    fn plural_zero_is_plural() {
618        assert_eq!(plural(0), "s");
619    }
620
621    #[test]
622    fn plural_one_is_singular() {
623        assert_eq!(plural(1), "");
624    }
625
626    #[test]
627    fn plural_two_is_plural() {
628        assert_eq!(plural(2), "s");
629    }
630
631    #[test]
632    fn plural_large_number() {
633        assert_eq!(plural(999), "s");
634    }
635
636    // ── elide_common_prefix edge cases ──────────────────────────
637
638    #[test]
639    fn elide_common_prefix_empty_base() {
640        assert_eq!(elide_common_prefix("", "src/foo.ts"), "src/foo.ts");
641    }
642
643    #[test]
644    fn elide_common_prefix_empty_target() {
645        assert_eq!(elide_common_prefix("src/foo.ts", ""), "");
646    }
647
648    #[test]
649    fn elide_common_prefix_both_empty() {
650        assert_eq!(elide_common_prefix("", ""), "");
651    }
652
653    #[test]
654    fn elide_common_prefix_same_file_different_extension() {
655        // "src/utils.ts" vs "src/utils.js" — common prefix is "src/"
656        assert_eq!(
657            elide_common_prefix("src/utils.ts", "src/utils.js"),
658            "utils.js"
659        );
660    }
661
662    #[test]
663    fn elide_common_prefix_partial_filename_match_not_stripped() {
664        // "src/App.tsx" vs "src/AppUtils.tsx" — both in src/, but file names differ
665        assert_eq!(
666            elide_common_prefix("src/App.tsx", "src/AppUtils.tsx"),
667            "AppUtils.tsx"
668        );
669    }
670
671    #[test]
672    fn elide_common_prefix_identical_paths() {
673        assert_eq!(elide_common_prefix("src/foo.ts", "src/foo.ts"), "foo.ts");
674    }
675
676    #[test]
677    fn split_dir_filename_single_slash() {
678        let (dir, file) = split_dir_filename("/file.ts");
679        assert_eq!(dir, "/");
680        assert_eq!(file, "file.ts");
681    }
682
683    #[test]
684    fn emit_json_returns_success_for_valid_value() {
685        let value = serde_json::json!({"key": "value"});
686        let code = emit_json(&value, "test");
687        assert_eq!(code, ExitCode::SUCCESS);
688    }
689
690    mod proptests {
691        use super::*;
692        use proptest::prelude::*;
693
694        proptest! {
695            /// split_dir_filename always reconstructs the original path.
696            #[test]
697            fn split_dir_filename_reconstructs_path(path in "[a-zA-Z0-9_./\\-]{0,100}") {
698                let (dir, file) = split_dir_filename(&path);
699                let reconstructed = format!("{dir}{file}");
700                prop_assert_eq!(
701                    reconstructed, path,
702                    "dir+file should reconstruct the original path"
703                );
704            }
705
706            /// plural returns either "" or "s", nothing else.
707            #[test]
708            fn plural_returns_empty_or_s(n: usize) {
709                let result = plural(n);
710                prop_assert!(
711                    result.is_empty() || result == "s",
712                    "plural should return \"\" or \"s\", got {:?}",
713                    result
714                );
715            }
716
717            /// plural(1) is always "" and plural(n != 1) is always "s".
718            #[test]
719            fn plural_singular_only_for_one(n: usize) {
720                let result = plural(n);
721                if n == 1 {
722                    prop_assert_eq!(result, "", "plural(1) should be empty");
723                } else {
724                    prop_assert_eq!(result, "s", "plural({}) should be \"s\"", n);
725                }
726            }
727
728            /// normalize_uri never panics and always replaces backslashes.
729            #[test]
730            fn normalize_uri_no_backslashes(path in "[a-zA-Z0-9_.\\\\/ \\[\\]%-]{0,100}") {
731                let result = normalize_uri(&path);
732                prop_assert!(
733                    !result.contains('\\'),
734                    "Result should not contain backslashes: {result}"
735                );
736            }
737
738            /// normalize_uri always encodes brackets.
739            #[test]
740            fn normalize_uri_encodes_all_brackets(path in "[a-zA-Z0-9_./\\[\\]%-]{0,80}") {
741                let result = normalize_uri(&path);
742                prop_assert!(
743                    !result.contains('[') && !result.contains(']'),
744                    "Result should not contain raw brackets: {result}"
745                );
746            }
747
748            /// elide_common_prefix always returns a suffix of or equal to target.
749            #[test]
750            fn elide_common_prefix_returns_suffix_of_target(
751                base in "[a-zA-Z0-9_./]{0,50}",
752                target in "[a-zA-Z0-9_./]{0,50}",
753            ) {
754                let result = elide_common_prefix(&base, &target);
755                prop_assert!(
756                    target.ends_with(result),
757                    "Result {:?} should be a suffix of target {:?}",
758                    result, target
759                );
760            }
761
762            /// relative_path never panics.
763            #[test]
764            fn relative_path_never_panics(
765                root in "/[a-zA-Z0-9_/]{0,30}",
766                suffix in "[a-zA-Z0-9_./]{0,30}",
767            ) {
768                let root_path = Path::new(&root);
769                let full = PathBuf::from(format!("{root}/{suffix}"));
770                let _ = relative_path(&full, root_path);
771            }
772        }
773    }
774}