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git_cli/
reset.rs

1use crate::prompt;
2use nils_common::git as common_git;
3use std::io::{self, BufRead, Write};
4use std::process::Output;
5
6pub fn dispatch(cmd: &str, args: &[String]) -> Option<i32> {
7    match cmd {
8        "soft" => Some(reset_by_count("soft", args)),
9        "mixed" => Some(reset_by_count("mixed", args)),
10        "hard" => Some(reset_by_count("hard", args)),
11        "undo" => Some(reset_undo()),
12        "back-head" => Some(back_head()),
13        "back-checkout" => Some(back_checkout()),
14        "remote" => Some(reset_remote(args)),
15        _ => None,
16    }
17}
18
19fn reset_by_count(mode: &str, args: &[String]) -> i32 {
20    let count_arg = args.first();
21    let extra_arg = args.get(1);
22    if extra_arg.is_some() {
23        eprintln!("❌ Too many arguments.");
24        eprintln!("Usage: git-reset-{mode} [N]");
25        return 2;
26    }
27
28    let count = match count_arg {
29        Some(value) => match parse_positive_int(value) {
30            Some(value) => value,
31            None => {
32                eprintln!("❌ Invalid commit count: {value} (must be a positive integer).");
33                eprintln!("Usage: git-reset-{mode} [N]");
34                return 2;
35            }
36        },
37        None => 1,
38    };
39
40    let target = format!("HEAD~{count}");
41    if !git_success(&["rev-parse", "--verify", "--quiet", &target]) {
42        eprintln!("❌ Cannot resolve {target} (not enough commits?).");
43        return 1;
44    }
45
46    let commit_label = if count > 1 {
47        format!("last {count} commits")
48    } else {
49        "last commit".to_string()
50    };
51
52    let (preface, prompt, failure, success) = match mode {
53        "soft" => (
54            vec![
55                format!("⚠️  This will rewind your {commit_label} (soft reset)"),
56                "🧠 Your changes will remain STAGED. Useful for rewriting commit message."
57                    .to_string(),
58            ],
59            format!("❓ Proceed with 'git reset --soft {target}'? [y/N] "),
60            "❌ Soft reset failed.".to_string(),
61            "✅ Reset completed. Your changes are still staged.".to_string(),
62        ),
63        "mixed" => (
64            vec![
65                format!("⚠️  This will rewind your {commit_label} (mixed reset)"),
66                "🧠 Your changes will become UNSTAGED and editable in working directory."
67                    .to_string(),
68            ],
69            format!("❓ Proceed with 'git reset --mixed {target}'? [y/N] "),
70            "❌ Mixed reset failed.".to_string(),
71            "✅ Reset completed. Your changes are now unstaged.".to_string(),
72        ),
73        "hard" => (
74            vec![
75                format!("⚠️  This will HARD RESET your repository to {target}."),
76                "🔥 Tracked staged/unstaged changes will be OVERWRITTEN.".to_string(),
77                format!("🧨 This is equivalent to: git reset --hard {target}"),
78            ],
79            "❓ Are you absolutely sure? [y/N] ".to_string(),
80            "❌ Hard reset failed.".to_string(),
81            format!("✅ Hard reset completed. HEAD moved back to {target}."),
82        ),
83        _ => {
84            eprintln!("❌ Unknown reset mode: {mode}");
85            return 2;
86        }
87    };
88
89    for line in preface {
90        println!("{line}");
91    }
92    println!("🧾 Commits to be rewound:");
93
94    let output = match git_output(&[
95        "log",
96        "--no-color",
97        "-n",
98        &count.to_string(),
99        "--date=format:%m-%d %H:%M",
100        "--pretty=%h %ad %an  %s",
101    ]) {
102        Some(output) => output,
103        None => return 1,
104    };
105    if !output.status.success() {
106        emit_output(&output);
107        return exit_code(&output);
108    }
109    emit_output(&output);
110
111    if !confirm_or_abort(&prompt) {
112        return 1;
113    }
114
115    let code = git_status(&["reset", &format!("--{mode}"), &target]).unwrap_or(1);
116    if code != 0 {
117        println!("{failure}");
118        return 1;
119    }
120
121    println!("{success}");
122    0
123}
124
125fn reset_undo() -> i32 {
126    if !git_success(&["rev-parse", "--is-inside-work-tree"]) {
127        println!("❌ Not a git repository.");
128        return 1;
129    }
130
131    let target_commit = match git_stdout_trimmed(&["rev-parse", "HEAD@{1}"]).and_then(non_empty) {
132        Some(value) => value,
133        None => {
134            println!("❌ Cannot resolve HEAD@{{1}} (no previous HEAD position in reflog).");
135            return 1;
136        }
137    };
138
139    let op_warnings = detect_in_progress_ops();
140    if !op_warnings.is_empty() {
141        println!("🛡️  Detected an in-progress Git operation:");
142        for warning in op_warnings {
143            println!("   - {warning}");
144        }
145        println!("⚠️  Resetting during these operations can be confusing.");
146        if !confirm_or_abort("❓ Still run git-reset-undo (move HEAD back)? [y/N] ") {
147            return 1;
148        }
149    }
150
151    let mut reflog_line_current =
152        git_stdout_trimmed(&["reflog", "-1", "--pretty=%h %gs", "HEAD@{0}"]).and_then(non_empty);
153    let mut reflog_subject_current =
154        git_stdout_trimmed(&["reflog", "-1", "--pretty=%gs", "HEAD@{0}"]).and_then(non_empty);
155
156    if reflog_line_current.is_none() || reflog_subject_current.is_none() {
157        reflog_line_current =
158            git_stdout_trimmed(&["reflog", "show", "-1", "--pretty=%h %gs", "HEAD"])
159                .and_then(non_empty);
160        reflog_subject_current =
161            git_stdout_trimmed(&["reflog", "show", "-1", "--pretty=%gs", "HEAD"])
162                .and_then(non_empty);
163    }
164
165    let mut reflog_line_target =
166        git_stdout_trimmed(&["reflog", "-1", "--pretty=%h %gs", "HEAD@{1}"]).and_then(non_empty);
167    if reflog_line_target.is_none() {
168        reflog_line_target = reflog_show_line(2, "%h %gs").and_then(non_empty);
169    }
170
171    let line_current = reflog_line_current.unwrap_or_else(|| "(unavailable)".to_string());
172    let line_target = reflog_line_target.unwrap_or_else(|| "(unavailable)".to_string());
173    let subject_current = reflog_subject_current.unwrap_or_else(|| "(unavailable)".to_string());
174
175    println!("🧾 Current HEAD@{{0}} (last action):");
176    println!("   {line_current}");
177    println!("🧾 Target  HEAD@{{1}} (previous HEAD position):");
178    println!("   {line_target}");
179
180    if line_current == "(unavailable)" || line_target == "(unavailable)" {
181        println!(
182            "ℹ️  Reflog display unavailable here; reset target is still the resolved SHA: {target_commit}"
183        );
184    }
185
186    if subject_current != "(unavailable)" && !subject_current.starts_with("reset:") {
187        println!("⚠️  The last action does NOT look like a reset operation.");
188        println!("🧠 It may be from checkout/rebase/merge/pull, etc.");
189        if !confirm_or_abort(
190            "❓ Still proceed to move HEAD back to the previous HEAD position? [y/N] ",
191        ) {
192            return 1;
193        }
194    }
195
196    println!("🕰  Target commit (resolved from HEAD@{{1}}):");
197    let log_output = match git_output(&["log", "--oneline", "-1", &target_commit]) {
198        Some(output) => output,
199        None => return 1,
200    };
201    if !log_output.status.success() {
202        emit_output(&log_output);
203        return exit_code(&log_output);
204    }
205    emit_output(&log_output);
206
207    let status_lines = match git_stdout_raw(&["status", "--porcelain"]) {
208        Some(value) => value,
209        None => return 1,
210    };
211
212    if status_lines.trim().is_empty() {
213        println!("✅ Working tree clean. Proceeding with: git reset --hard {target_commit}");
214        let code = git_status(&["reset", "--hard", &target_commit]).unwrap_or(1);
215        if code != 0 {
216            println!("❌ Hard reset failed.");
217            return 1;
218        }
219        println!("✅ Repository reset back to previous HEAD: {target_commit}");
220        return 0;
221    }
222
223    println!("⚠️  Working tree has changes:");
224    print!("{status_lines}");
225    if !status_lines.ends_with('\n') {
226        println!();
227    }
228    println!();
229    println!("Choose how to proceed:");
230    println!(
231        "  1) Keep changes + PRESERVE INDEX (staged vs new base)  (git reset --soft  {target_commit})"
232    );
233    println!(
234        "  2) Keep changes + UNSTAGE ALL                          (git reset --mixed {target_commit})"
235    );
236    println!(
237        "  3) Discard tracked changes                             (git reset --hard  {target_commit})"
238    );
239    println!("  4) Abort");
240
241    let choice = match read_line("❓ Select [1/2/3/4] (default: 4): ") {
242        Ok(value) => value,
243        Err(_) => {
244            println!("🚫 Aborted");
245            return 1;
246        }
247    };
248
249    match choice.as_str() {
250        "1" => {
251            println!(
252                "🧷 Preserving INDEX (staged) and working tree. Running: git reset --soft {target_commit}"
253            );
254            println!(
255                "⚠️  Note: The index is preserved, but what appears staged is relative to the new HEAD."
256            );
257            let code = git_status(&["reset", "--soft", &target_commit]).unwrap_or(1);
258            if code != 0 {
259                println!("❌ Soft reset failed.");
260                return 1;
261            }
262            println!("✅ HEAD moved back while preserving index + working tree: {target_commit}");
263            0
264        }
265        "2" => {
266            println!(
267                "🧷 Preserving working tree but clearing INDEX (unstage all). Running: git reset --mixed {target_commit}"
268            );
269            let code = git_status(&["reset", "--mixed", &target_commit]).unwrap_or(1);
270            if code != 0 {
271                println!("❌ Mixed reset failed.");
272                return 1;
273            }
274            println!("✅ HEAD moved back; working tree preserved; index reset: {target_commit}");
275            0
276        }
277        "3" => {
278            println!("🔥 Discarding tracked changes. Running: git reset --hard {target_commit}");
279            println!("⚠️  This overwrites tracked files in working tree + index.");
280            println!("ℹ️  Untracked files are NOT removed by reset --hard.");
281            if !confirm_or_abort("❓ Are you absolutely sure? [y/N] ") {
282                return 1;
283            }
284            let code = git_status(&["reset", "--hard", &target_commit]).unwrap_or(1);
285            if code != 0 {
286                println!("❌ Hard reset failed.");
287                return 1;
288            }
289            println!("✅ Repository reset back to previous HEAD: {target_commit}");
290            0
291        }
292        _ => {
293            println!("🚫 Aborted");
294            1
295        }
296    }
297}
298
299fn back_head() -> i32 {
300    let prev_head = match git_stdout_trimmed(&["rev-parse", "HEAD@{1}"]).and_then(non_empty) {
301        Some(value) => value,
302        None => {
303            println!("❌ Cannot find previous HEAD in reflog.");
304            return 1;
305        }
306    };
307
308    println!("⏪ This will move HEAD back to the previous position (HEAD@{{1}}):");
309    if let Some(oneline) = git_stdout_trimmed(&["log", "--oneline", "-1", &prev_head]) {
310        println!("🔁 {oneline}");
311    }
312    if !confirm_or_abort("❓ Proceed with 'git checkout HEAD@{1}'? [y/N] ") {
313        return 1;
314    }
315
316    let code = git_status(&["checkout", "HEAD@{1}"]).unwrap_or(1);
317    if code != 0 {
318        println!("❌ Checkout failed (likely due to local changes or invalid reflog state).");
319        return 1;
320    }
321
322    println!("✅ Restored to previous HEAD (HEAD@{{1}}): {prev_head}");
323    0
324}
325
326fn back_checkout() -> i32 {
327    let current_branch =
328        match git_stdout_trimmed(&["rev-parse", "--abbrev-ref", "HEAD"]).and_then(non_empty) {
329            Some(value) => value,
330            None => {
331                println!("❌ Cannot determine current branch.");
332                return 1;
333            }
334        };
335
336    if current_branch == "HEAD" {
337        println!(
338            "❌ You are in a detached HEAD state. This function targets branch-to-branch checkouts."
339        );
340        println!(
341            "🧠 Tip: Use `git reflog` to find the branch/commit you want, then `git checkout <branch>`."
342        );
343        return 1;
344    }
345
346    let from_branch = match find_previous_checkout(&current_branch) {
347        Some(value) => value,
348        None => {
349            println!("❌ Could not find a previous checkout that switched to {current_branch}.");
350            return 1;
351        }
352    };
353
354    if from_branch.len() >= 7
355        && from_branch.len() <= 40
356        && from_branch.chars().all(|c| c.is_ascii_hexdigit())
357    {
358        println!(
359            "❌ Previous 'from' looks like a commit SHA ({from_branch}). Refusing to checkout to avoid detached HEAD."
360        );
361        println!("🧠 Use `git reflog` to choose the correct branch explicitly.");
362        return 1;
363    }
364
365    if !git_success(&[
366        "show-ref",
367        "--verify",
368        "--quiet",
369        &format!("refs/heads/{from_branch}"),
370    ]) {
371        println!("❌ '{from_branch}' is not an existing local branch.");
372        println!("🧠 If it's a remote branch, try: git checkout -t origin/{from_branch}");
373        return 1;
374    }
375
376    println!("⏪ This will move HEAD back to previous branch: {from_branch}");
377    if !confirm_or_abort(&format!(
378        "❓ Proceed with 'git checkout {from_branch}'? [y/N] "
379    )) {
380        return 1;
381    }
382
383    let code = git_status(&["checkout", &from_branch]).unwrap_or(1);
384    if code != 0 {
385        println!("❌ Checkout failed (likely due to local changes or conflicts).");
386        return 1;
387    }
388
389    println!("✅ Restored to previous branch: {from_branch}");
390    0
391}
392
393fn reset_remote(args: &[String]) -> i32 {
394    let mut want_help = false;
395    let mut want_yes = false;
396    let mut want_fetch = true;
397    let mut want_prune = false;
398    let mut want_clean = false;
399    let mut want_set_upstream = false;
400    let mut remote_arg: Option<String> = None;
401    let mut branch_arg: Option<String> = None;
402    let mut ref_arg: Option<String> = None;
403
404    let mut i = 0usize;
405    while i < args.len() {
406        let arg = args[i].as_str();
407        match arg {
408            "-h" | "--help" => {
409                want_help = true;
410            }
411            "-y" | "--yes" => {
412                want_yes = true;
413            }
414            "-r" | "--remote" => {
415                let Some(value) = args.get(i + 1) else {
416                    return 2;
417                };
418                remote_arg = Some(value.to_string());
419                i += 1;
420            }
421            "-b" | "--branch" => {
422                let Some(value) = args.get(i + 1) else {
423                    return 2;
424                };
425                branch_arg = Some(value.to_string());
426                i += 1;
427            }
428            "--ref" => {
429                let Some(value) = args.get(i + 1) else {
430                    return 2;
431                };
432                ref_arg = Some(value.to_string());
433                i += 1;
434            }
435            "--no-fetch" => {
436                want_fetch = false;
437            }
438            "--prune" => {
439                want_prune = true;
440            }
441            "--clean" => {
442                want_clean = true;
443            }
444            "--set-upstream" => {
445                want_set_upstream = true;
446            }
447            _ => {}
448        }
449        i += 1;
450    }
451
452    if want_help {
453        print_reset_remote_help();
454        return 0;
455    }
456
457    let mut remote = remote_arg.clone().unwrap_or_default();
458    let mut remote_branch = branch_arg.clone().unwrap_or_default();
459
460    if let Some(reference) = ref_arg {
461        let Some((remote_ref, branch_ref)) = reference.split_once('/') else {
462            eprintln!("❌ --ref must look like '<remote>/<branch>' (got: {reference})");
463            return 2;
464        };
465        remote = remote_ref.to_string();
466        remote_branch = branch_ref.to_string();
467    }
468
469    if !git_success(&["rev-parse", "--git-dir"]) {
470        eprintln!("❌ Not inside a Git repository.");
471        return 1;
472    }
473
474    let current_branch = match git_stdout_trimmed(&["symbolic-ref", "--quiet", "--short", "HEAD"])
475        .and_then(non_empty)
476    {
477        Some(value) => value,
478        None => {
479            eprintln!("❌ Detached HEAD. Switch to a branch first.");
480            return 1;
481        }
482    };
483
484    let upstream =
485        git_stdout_trimmed(&["rev-parse", "--abbrev-ref", "--symbolic-full-name", "@{u}"])
486            .unwrap_or_default();
487
488    if remote.is_empty()
489        && let Some((remote_ref, _)) = upstream.split_once('/')
490    {
491        remote = remote_ref.to_string();
492    }
493    if remote.is_empty() {
494        remote = "origin".to_string();
495    }
496
497    if remote_branch.is_empty() {
498        if let Some((_, branch_ref)) = upstream.split_once('/')
499            && branch_ref != "HEAD"
500        {
501            remote_branch = branch_ref.to_string();
502        }
503        if remote_branch.is_empty() {
504            remote_branch = current_branch.clone();
505        }
506    }
507
508    let target_ref = format!("{remote}/{remote_branch}");
509
510    if want_fetch {
511        let fetch_args = if want_prune {
512            vec!["fetch", "--prune", "--", &remote]
513        } else {
514            vec!["fetch", "--", &remote]
515        };
516        let code = git_status(&fetch_args).unwrap_or(1);
517        if code != 0 {
518            return code;
519        }
520    }
521
522    if !git_success(&[
523        "show-ref",
524        "--verify",
525        "--quiet",
526        &format!("refs/remotes/{remote}/{remote_branch}"),
527    ]) {
528        eprintln!("❌ Remote-tracking branch not found: {target_ref}");
529        eprintln!("   Try: git fetch --prune -- {remote}");
530        eprintln!("   Or verify: git branch -r | rg -n -- \"^\\\\s*{remote}/{remote_branch}$\"");
531        return 1;
532    }
533
534    let status_porcelain = git_stdout_raw(&["status", "--porcelain"]).unwrap_or_default();
535    if !want_yes {
536        println!("⚠️  This will OVERWRITE local branch '{current_branch}' with '{target_ref}'.");
537        if !status_porcelain.trim().is_empty() {
538            println!("🔥 Tracked staged/unstaged changes will be DISCARDED by --hard.");
539            println!("🧹 Untracked files will be kept (use --clean to remove).");
540        }
541        if !confirm_or_abort(&format!(
542            "❓ Proceed with: git reset --hard {target_ref} ? [y/N] "
543        )) {
544            return 1;
545        }
546    }
547
548    let code = git_status(&["reset", "--hard", &target_ref]).unwrap_or(1);
549    if code != 0 {
550        return code;
551    }
552
553    if want_clean {
554        if !want_yes {
555            println!("⚠️  Next: git clean -fd (removes untracked files/dirs)");
556            let ok = prompt::confirm("❓ Proceed with: git clean -fd ? [y/N] ").unwrap_or_default();
557            if !ok {
558                println!("ℹ️  Skipped git clean -fd");
559                want_clean = false;
560            }
561        }
562        if want_clean {
563            let code = git_status(&["clean", "-fd"]).unwrap_or(1);
564            if code != 0 {
565                return code;
566            }
567        }
568    }
569
570    if want_set_upstream || upstream.is_empty() {
571        let _ = git_status(&["branch", "--set-upstream-to", &target_ref, &current_branch]);
572    }
573
574    println!("✅ Done. '{current_branch}' now matches '{target_ref}'.");
575    0
576}
577
578fn parse_positive_int(raw: &str) -> Option<i64> {
579    if raw.is_empty() || !raw.chars().all(|c| c.is_ascii_digit()) {
580        return None;
581    }
582    let value = raw.parse::<i64>().ok()?;
583    if value <= 0 { None } else { Some(value) }
584}
585
586fn detect_in_progress_ops() -> Vec<String> {
587    let mut warnings = Vec::new();
588    if git_path_exists("MERGE_HEAD", true) {
589        warnings.push("merge in progress (suggest: git merge --abort)".to_string());
590    }
591    if git_path_exists("rebase-apply", false) || git_path_exists("rebase-merge", false) {
592        warnings.push("rebase in progress (suggest: git rebase --abort)".to_string());
593    }
594    if git_path_exists("CHERRY_PICK_HEAD", true) {
595        warnings.push("cherry-pick in progress (suggest: git cherry-pick --abort)".to_string());
596    }
597    if git_path_exists("REVERT_HEAD", true) {
598        warnings.push("revert in progress (suggest: git revert --abort)".to_string());
599    }
600    if git_path_exists("BISECT_LOG", true) {
601        warnings.push("bisect in progress (suggest: git bisect reset)".to_string());
602    }
603    warnings
604}
605
606fn git_path_exists(name: &str, is_file: bool) -> bool {
607    let output = git_stdout_trimmed(&["rev-parse", "--git-path", name]);
608    let Some(path) = output else {
609        return false;
610    };
611    let path = std::path::Path::new(&path);
612    if is_file {
613        path.is_file()
614    } else {
615        path.is_dir()
616    }
617}
618
619fn reflog_show_line(index: usize, pretty: &str) -> Option<String> {
620    let output = git_stdout_raw(&[
621        "reflog",
622        "show",
623        "-2",
624        &format!("--pretty={pretty}"),
625        "HEAD",
626    ])?;
627    output.lines().nth(index - 1).map(|line| line.to_string())
628}
629
630fn find_previous_checkout(current_branch: &str) -> Option<String> {
631    let output = git_stdout_raw(&["reflog", "--format=%gs"])?;
632    for line in output.lines() {
633        if !line.starts_with("checkout: moving from ") {
634            continue;
635        }
636        if !line.ends_with(&format!(" to {current_branch}")) {
637            continue;
638        }
639        let mut value = line.trim_start_matches("checkout: moving from ");
640        value = value.trim_end_matches(&format!(" to {current_branch}"));
641        return Some(value.to_string());
642    }
643    None
644}
645
646fn confirm_or_abort(prompt: &str) -> bool {
647    prompt::confirm_or_abort(prompt).is_ok()
648}
649
650fn read_line(prompt: &str) -> io::Result<String> {
651    let mut output = io::stdout();
652    output.write_all(prompt.as_bytes())?;
653    output.flush()?;
654    let mut input = String::new();
655    io::stdin().lock().read_line(&mut input)?;
656    Ok(input.trim_end_matches(['\n', '\r']).to_string())
657}
658
659fn git_output(args: &[&str]) -> Option<Output> {
660    common_git::run_output(args).ok()
661}
662
663fn git_status(args: &[&str]) -> Option<i32> {
664    common_git::run_status_inherit(args)
665        .ok()
666        .map(|status| status.code().unwrap_or(1))
667}
668
669fn git_success(args: &[&str]) -> bool {
670    matches!(git_output(args), Some(output) if output.status.success())
671}
672
673fn git_stdout_trimmed(args: &[&str]) -> Option<String> {
674    let output = git_output(args)?;
675    if !output.status.success() {
676        return None;
677    }
678    Some(trim_trailing_newlines(&String::from_utf8_lossy(
679        &output.stdout,
680    )))
681}
682
683fn git_stdout_raw(args: &[&str]) -> Option<String> {
684    let output = git_output(args)?;
685    if !output.status.success() {
686        return None;
687    }
688    Some(String::from_utf8_lossy(&output.stdout).to_string())
689}
690
691fn trim_trailing_newlines(input: &str) -> String {
692    input.trim_end_matches(['\n', '\r']).to_string()
693}
694
695fn non_empty(value: String) -> Option<String> {
696    if value.is_empty() { None } else { Some(value) }
697}
698
699fn emit_output(output: &Output) {
700    let _ = io::stdout().write_all(&output.stdout);
701    let _ = io::stderr().write_all(&output.stderr);
702}
703
704fn exit_code(output: &Output) -> i32 {
705    output.status.code().unwrap_or(1)
706}
707
708fn print_reset_remote_help() {
709    println!(
710        "git-reset-remote: overwrite current local branch with a remote-tracking branch (DANGEROUS)"
711    );
712    println!();
713    println!("Usage:");
714    println!("  git-reset-remote  # reset current branch to its upstream (or origin/<branch>)");
715    println!("  git-reset-remote --ref origin/main");
716    println!("  git-reset-remote -r origin -b main");
717    println!();
718    println!("Options:");
719    println!("  -r, --remote <name>        Remote name (default: from upstream, else origin)");
720    println!(
721        "  -b, --branch <name>        Remote branch name (default: from upstream, else current branch)"
722    );
723    println!("      --ref <remote/branch>  Shortcut for --remote/--branch");
724    println!("      --no-fetch             Skip 'git fetch' (uses existing remote-tracking refs)");
725    println!("      --prune                Use 'git fetch --prune'");
726    println!("      --set-upstream         Set upstream of current branch to <remote>/<branch>");
727    println!(
728        "      --clean                After reset, optionally run 'git clean -fd' (removes untracked)"
729    );
730    println!("  -y, --yes                  Skip confirmations");
731}
732
733#[cfg(test)]
734mod tests {
735    use super::{dispatch, non_empty, parse_positive_int, trim_trailing_newlines};
736    use nils_test_support::{CwdGuard, GlobalStateLock};
737    use pretty_assertions::assert_eq;
738
739    #[test]
740    fn dispatch_returns_none_for_unknown_subcommand() {
741        assert_eq!(dispatch("unknown", &[]), None);
742    }
743
744    #[test]
745    fn parse_positive_int_accepts_digits_only() {
746        assert_eq!(parse_positive_int("1"), Some(1));
747        assert_eq!(parse_positive_int("42"), Some(42));
748        assert_eq!(parse_positive_int("001"), Some(1));
749    }
750
751    #[test]
752    fn parse_positive_int_rejects_invalid_values() {
753        assert_eq!(parse_positive_int(""), None);
754        assert_eq!(parse_positive_int("0"), None);
755        assert_eq!(parse_positive_int("-1"), None);
756        assert_eq!(parse_positive_int("1.0"), None);
757        assert_eq!(parse_positive_int("abc"), None);
758    }
759
760    #[test]
761    fn trim_trailing_newlines_only_removes_line_endings() {
762        assert_eq!(trim_trailing_newlines("line\n"), "line");
763        assert_eq!(trim_trailing_newlines("line\r\n"), "line");
764        assert_eq!(trim_trailing_newlines("line  "), "line  ");
765    }
766
767    #[test]
768    fn non_empty_returns_none_for_empty_string() {
769        assert_eq!(non_empty(String::new()), None);
770        assert_eq!(non_empty("value".to_string()), Some("value".to_string()));
771    }
772
773    #[test]
774    fn reset_by_count_modes_return_usage_errors_for_invalid_arguments() {
775        let lock = GlobalStateLock::new();
776        let dir = tempfile::TempDir::new().expect("tempdir");
777        let _cwd = CwdGuard::set(&lock, dir.path()).expect("cwd");
778
779        let args = vec!["1".to_string(), "2".to_string()];
780        assert_eq!(dispatch("soft", &args), Some(2));
781        assert_eq!(dispatch("mixed", &args), Some(2));
782        assert_eq!(dispatch("hard", &args), Some(2));
783
784        let args = vec!["abc".to_string()];
785        assert_eq!(dispatch("soft", &args), Some(2));
786    }
787
788    #[test]
789    fn reset_by_count_returns_runtime_error_when_target_commit_missing() {
790        let lock = GlobalStateLock::new();
791        let dir = tempfile::TempDir::new().expect("tempdir");
792        let _cwd = CwdGuard::set(&lock, dir.path()).expect("cwd");
793        let args = vec!["999999".to_string()];
794        assert_eq!(dispatch("soft", &args), Some(1));
795    }
796
797    #[test]
798    fn reset_remote_argument_parsing_covers_help_and_usage_failures() {
799        let help_args = vec!["--help".to_string()];
800        assert_eq!(dispatch("remote", &help_args), Some(0));
801
802        let bad_ref_args = vec!["--ref".to_string(), "invalid".to_string()];
803        assert_eq!(dispatch("remote", &bad_ref_args), Some(2));
804
805        let missing_remote_value = vec!["--remote".to_string()];
806        assert_eq!(dispatch("remote", &missing_remote_value), Some(2));
807    }
808}