Claude AI

[tasleson]

Misc. improvements using claude

Summary by CodeRabbit

• New Features
  • Added library-backed duplicate detection with CLI support: globbed file input, configurable line thresholds, ignore-list file, text/JSON output, and multithreaded processing.
• Refactor
  • CLI now delegates to the library with centralized error handling and safer thread pool setup.
• Documentation
  • Updated README usage version to 0.9.3.
• Tests
  • Introduced comprehensive integration tests across hashing, rolling windows, file mapping, and collision detection.
• Chores
  • Upgraded Rust edition to 2021 and added a development dependency for testing.

[coderabbitai]

Walkthrough

Introduces a new reusable library (src/lib.rs) for duplicate-text detection, refactors main to use the library, updates Cargo.toml to edition 2021 and adds a dev-dependency, adjusts README version text, and adds comprehensive integration tests validating hashing, rolling windows, collision detection, file mapping, and reporting paths.

Changes

Cohort / File(s)	Summary
Build & metadata Cargo.toml	Update Rust edition to 2021; add [dev-dependencies] with tempfile = "3.0". No changes to main dependencies’ APIs.
Documentation README.md	Update usage snippet version string from 0.9.0 to 0.9.3.
Library: duplicate detection core src/lib.rs	Add new library implementing end-to-end duplicate detection: file discovery, per-line signatures, rolling hashes, collision detection/merging, reporting (text/JSON), ignore list, threading. Exposes Options, Collision, FileId, LineId, error type DupliError, helpers, and process_files/process_report.
CLI refactor to library src/main.rs	Replace inline implementation with calls to the new library. Switch error type to rags_rs::Error. Configure Rayon thread pool, load ignore hashes via library, call process_files and process_report. Remove local Options.
Tests tests/integration_tests.rs	Add integration tests covering hashing, rolling windows, file signatures, FileId mapping, collision logic (overlap, maximize_collision, Collision::scrub), edge cases, and multi-file scenarios using temp files.

Sequence Diagram(s)

sequenceDiagram
  autonumber
  actor User
  participant CLI as main.rs (CLI)
  participant Lib as duplihere::process_files
  participant FS as Filesystem
  participant Hash as Signatures & Rolling Hashes
  participant Col as Collision Detector
  participant Rep as Reporting

  User->>CLI: Run with args (globs, lines, print/json, ignore, threads)
  CLI->>Lib: process_files(Options)
  Lib->>FS: files_to_process(globs)
  FS-->>Lib: [(file_id, name)] 
  par parallel per file
    Lib->>Hash: file_signatures(file)
    Hash-->>Lib: Vec<u64>
  end
  Lib->>Hash: rolling_hashes(signatures, min_lines)
  Lib->>Col: find_collisions(...)
  Col-->>Lib: DashMap<key, Collision>
  Lib-->>CLI: results

  CLI->>Rep: process_report(results, Options, ignore_hashes)
  alt json
    Rep->>CLI: print JSON
  else text
    Rep->>CLI: print text
  end
  CLI-->>User: Exit 0 or error

Loading

Estimated code review effort

🎯 4 (Complex) | ⏱️ ~75 minutes

Poem

In burrows of code, I hop and compare,
Lines in a row, duplicates laid bare.
A library blooms where main once sprawled,
Hashes roll on, collisions called.
Tests like carrots, crisp and bright—
0.9.3, we launch tonight! 🥕✨

Pre-merge checks and finishing touches

❌ Failed checks (1 inconclusive)

Check name	Status	Explanation	Resolution
Title Check	❓ Inconclusive	The PR title "Claude AI" is vague and does not describe the primary code changes in this branch; the diff actually introduces a new duplihere library implementing multi-file duplicate-text detection, refactors main to use that library, updates Cargo and README, and adds comprehensive integration tests. Because the title references a tooling aid rather than summarizing the functional change, it does not give reviewers a clear sense of the PR's intent or scope. This makes the title insufficient for quick history scanning or review triage.	Please replace the title with a concise, change-focused summary such as "Add duplihere library for multi-file duplicate detection and refactor main" or "Introduce duplihere crate and integration tests; refactor CLI to use library", so the title highlights the primary functional change rather than the tooling used.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

✨ Finishing touches

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• Post copyable unit tests in a comment
• Commit unit tests in branch claude_demo

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[coderabbitai]

Actionable comments posted: 6

🧹 Nitpick comments (8)

Cargo.toml (1)

19-20: Loosen dev-dep pin to receive compatible fixes automatically

Use a caret range so CI picks up non-breaking fixes (security/bug) in 3.x without manual bumps.

-[dev-dependencies]
-tempfile = "3.0"
+[dev-dependencies]
+tempfile = "3"

README.md (1)

30-31: Typo: “indention” → “indentation”

Minor doc polish.

-The duplicated text can be at different levels of indention,
+The duplicated text can be at different levels of indentation,

tests/integration_tests.rs (3)

521-526: Align with stricter collision semantics

Same rationale: prefer None over Some(num_lines=0).

-    let collision3 = maximize_collision(&file_hashes, &left3, &right3, 2);
-    // Should not match [4,5] vs [99,98] - might return Some with 0 lines
-    if let Some(collision3) = collision3 {
-        assert_eq!(collision3.num_lines, 0);
-    }
+    let collision3 = maximize_collision(&file_hashes, &left3, &right3, 2);
+    assert!(collision3.is_none());

---

557-560: Avoid accepting 0-line “matches”

Tighten to None to reflect true non-match.

-    let collision2 = maximize_collision(&file_hashes, &left, &right2, min_lines);
-    // maximize_collision might return Some with 0 lines instead of None
-    if let Some(collision2) = collision2 {
-        assert_eq!(collision2.num_lines, 0);
-    }
+    let collision2 = maximize_collision(&file_hashes, &left, &right2, min_lines);
+    assert!(collision2.is_none());

---

398-405: Comment nit: braces

The comment says “both '}'” but the file content writes “}}”. Tests are correct; tweak the comment to reduce confusion.

-// Lines 1 and 3 should have the same signature (both "}")
+// Lines 3 and 7 should have the same signature (both "}}")

src/lib.rs (3)

631-668: Global FILE_LOOKUP locking scope

You hold the FILE_LOOKUP mutex across I/O (glob + canonicalize). Not an issue here (single-threaded phase), but annotate this invariant or narrow the lock if you ever parallelize discovery.

---

703-710: Clarify Arc → &str conversion

The implicit deref from &Arc to &str works, but using as_str() is clearer.

-        if let Err(err) = process_file(
-            e.0,
-            &e.1,
+        if let Err(err) = process_file(
+            e.0,
+            e.1.as_str(),
             opts.lines as usize,
             &file_hashes,
             &collision_hashes,
         ) {

---

372-442: print_report: prefer HashSet for ignore lookups

Use HashSet for ignore lookups; drop bool payload.

-pub fn print_report(
-    printable_results: &[Collision],
-    opts: &Options,
-    ignore_hashes: &HashMap<u64, bool>,
-) -> Result<()> {
+pub fn print_report(
+    printable_results: &[Collision],
+    opts: &Options,
+    ignore_hashes: &std::collections::HashSet<u64>,
+) -> Result<()> {
@@
-        if ignore_hashes.contains_key(&p.key) {
+        if ignore_hashes.contains(&p.key) {

And in get_ignore_hashes:

-pub fn get_ignore_hashes(file_name: &str) -> Result<HashMap<u64, bool>> {
-    let mut ignores: HashMap<u64, bool> = HashMap::new();
+pub fn get_ignore_hashes(file_name: &str) -> Result<std::collections::HashSet<u64>> {
+    let mut ignores: std::collections::HashSet<u64> = std::collections::HashSet::new();
@@
-                    ignores.insert(hv, true);
+                    ignores.insert(hv);

Propagate type changes to callers (main.rs, process_report).

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 5586b6d and 433a968.

📒 Files selected for processing (5)

• Cargo.toml (2 hunks)
• README.md (1 hunks)
• src/lib.rs (1 hunks)
• src/main.rs (3 hunks)
• tests/integration_tests.rs (1 hunks)

🧰 Additional context used

🧬 Code graph analysis (2)

tests/integration_tests.rs (1)

src/lib.rs (8)

• calculate_hash (89-93)
• rolling_hashes (121-140)
• new (592-598)
• id_to_name (621-623)
• number_files (626-628)
• file_signatures (97-115)
• overlap (290-297)
• maximize_collision (301-348)

src/main.rs (1)

src/lib.rs (3)

• new (592-598)
• get_ignore_hashes (543-565)
• process_files (696-720)

🔇 Additional comments (9)

Cargo.toml (2)

5-5: Edition 2021: good upgrade

Edition bump aligns with current tooling and lets you use 2021 idioms without friction.

---

9-18: Confirm these versions are deliberate: rayon 1.3.0 and dashmap 5.5.0 (Cargo.toml lines 9–18)
rayon 1.3.0 and dashmap 5.5.0 may be older; if not intentionally pinned, bump them under semver to pick up fixes/optimizations for parallel-sorts/raw-shards usage.
Verification here failed (no configured Rust toolchain). Run locally and paste outputs:
rustup default stable

if you need -Z flags: rustup default nightly

cargo update -Z minimal-versions
cargo tree -i rayon
cargo tree -i dashmap

README.md (1)

24-24: Version string update: LGTM

Matches Cargo version 0.9.3.

src/main.rs (2)

16-58: Return-based main is fine

Result-returning main with rags_rs errors is clean and consistent.

---

73-81: Ignore-file load: good UX with specific exit code

Clear message and exit code 2. Consider bubbling errors instead if this binary ever becomes a library entry-point.

tests/integration_tests.rs (1)

257-281: OK: exact-match maximize_collision happy path

Solid coverage for multi-file exact sequence growth.

src/lib.rs (3)

121-140: Consecutive-duplicate suppression: good

rolling_hashes avoids back-to-back duplicates; windowing logic is sound.

---

350-369: print_dup_text: boundary handling looks correct

Reads and prints inclusive range as intended; no changes needed.

---

399-407: Off-by-one: end line in human-readable output

End should be inclusive (start + num_lines - 1). Current code prints one past the last line.

-                    let start_line = spec_file.line_number;
-                    let end_line = start_line + p.num_lines;
+                    let start_line = spec_file.line_number;
+                    let end_line = start_line + p.num_lines.saturating_sub(1);
                     println!(
                         "Between lines {} and {} in {}",
                         start_line + 1,
                         end_line,
                         filename
                     );

Likely an incorrect or invalid review comment.

[coderabbitai]

⚠️ Potential issue

Return None for sub-threshold matches to prevent 0-line “collisions”

When the rolling-hash collides but actual line hashes differ immediately, offset stays 0. Returning Some with num_lines=0 pollutes results and downstream reporting.

     // If after walking we overlap skip too
-    if overlap(l_info, r_info, offset) {
+    if offset < min_lines {
+        return None;
+    }
+    if overlap(l_info, r_info, offset) {
         return None;
     }

Update related tests as suggested in tests/integration_tests.rs.

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	// If after walking we overlap skip too
	if overlap(l_info, r_info, offset) {
	return None;
	}
	let files: Vec<LineId> = vec![*l_info, *r_info];
	Some(Collision {
	key: s.finish(),
	num_lines: offset,
	start_lines: files,
	sig: 0,
	})
	}
	// If after walking we overlap skip too
	if offset < min_lines {
	return None;
	}
	if overlap(l_info, r_info, offset) {
	return None;
	}
	let files: Vec<LineId> = vec![*l_info, *r_info];
	Some(Collision {
	key: s.finish(),
	num_lines: offset,
	start_lines: files,
	sig: 0,
	})
	}

🤖 Prompt for AI Agents

In src/lib.rs around lines 336 to 348, the function currently returns
Some(Collision) even when offset is 0, producing a 0-line collision; change the
logic to return None when offset == 0 so sub-threshold (immediate mismatch)
matches are ignored, and update the related tests in tests/integration_tests.rs
to expect no collision in that case (adjust assertions/expected outputs
accordingly).

[coderabbitai]

🛠️ Refactor suggestion

Library should not exit the process

process_report calls process::exit(1) on error, which is surprising for a library. Return Result and let the binary decide exit codes. See main.rs comment for coordinated change.

-pub fn process_report(
+pub fn process_report(
     results_hash: DashMap<u64, Collision>,
     opts: &Options,
     ignore_hashes: &HashMap<u64, bool>,
-) {
+) -> Result<()> {
@@
-    if let Err(e) = print_report(&printable_results, opts, ignore_hashes) {
-        eprintln!("ERROR: Failed to print report: {}", e);
-        process::exit(1);
-    }
+    print_report(&printable_results, opts, ignore_hashes)?;
-}
+    Ok(())
+}

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	pub fn process_report(
	results_hash: DashMap<u64, Collision>,
	opts: &Options,
	ignore_hashes: &HashMap<u64, bool>,
	) {
	let mut final_report: Vec<Collision> = results_hash.into_iter().map(|(_, v)| v).collect();
	final_report.par_sort_unstable_by(|a, b| a.num_lines.cmp(&b.num_lines).reverse());
	let mut printable_results: Vec<Collision> = Vec::new();
	{
	let mut chunk_processed: HashMap<u64, bool> = HashMap::new();
	final_report.par_iter_mut().for_each(|ea| ea.scrub());
	for ea in final_report {
	let cs = ea.signature();
	if let std::collections::hash_map::Entry::Vacant(e) = chunk_processed.entry(cs) {
	e.insert(true);
	printable_results.push(ea);
	}
	}
	}
	printable_results.par_sort_unstable_by(|a, b| {
	a.num_lines
	.cmp(&b.num_lines)
	.then_with(|| {
	a.start_lines[0]
	.line_number
	.cmp(&b.start_lines[0].line_number)
	})
	.then_with(|| a.start_lines[0].file_id.cmp(&b.start_lines[0].file_id))
	});
	if let Err(e) = print_report(&printable_results, opts, ignore_hashes) {
	eprintln!("ERROR: Failed to print report: {}", e);
	process::exit(1);
	}
	}
	pub fn process_report(
	results_hash: DashMap<u64, Collision>,
	opts: &Options,
	ignore_hashes: &HashMap<u64, bool>,
	) -> Result<()> {
	let mut final_report: Vec<Collision> = results_hash.into_iter().map(|(_, v)| v).collect();
	final_report.par_sort_unstable_by(|a, b| a.num_lines.cmp(&b.num_lines).reverse());
	let mut printable_results: Vec<Collision> = Vec::new();
	{
	let mut chunk_processed: HashMap<u64, bool> = HashMap::new();
	final_report.par_iter_mut().for_each(|ea| ea.scrub());
	for ea in final_report {
	let cs = ea.signature();
	if let std::collections::hash_map::Entry::Vacant(e) = chunk_processed.entry(cs) {
	e.insert(true);
	printable_results.push(ea);
	}
	}
	}
	printable_results.par_sort_unstable_by(|a, b| {
	a.num_lines
	.cmp(&b.num_lines)
	.then_with(|| {
	a.start_lines[0]
	.line_number
	.cmp(&b.start_lines[0].line_number)
	})
	.then_with(|| a.start_lines[0].file_id.cmp(&b.start_lines[0].file_id))
	});
	print_report(&printable_results, opts, ignore_hashes)?;
	Ok(())
	}

🤖 Prompt for AI Agents

In src/lib.rs around lines 500 to 539, process_report currently calls
process::exit(1) when print_report fails which is inappropriate for a library;
change the function to return a Result<(), E> (choose the crate convention e.g.,
anyhow::Result<()> or Result<(), Box<dyn std::error::Error + Send + Sync>>)
instead of returning unit, remove the process::exit call, and propagate the
print_report error back to the caller (use the ? operator or map_err to convert
error types as needed), ensuring you return Ok(()) on success; update callers
(e.g., the binary in main.rs) to handle the Result and decide exit codes.

[coderabbitai]

🛠️ Refactor suggestion

Don’t exit from a library on counter overflow

Exiting the process from FileId::register_file is hostile to embedders. Return an error and let callers decide.

-    pub fn register_file(&mut self, file_name: Arc<String>) -> Option<u32> {
+    pub fn register_file(&mut self, file_name: Arc<String>) -> Option<u32> {
@@
-        if let Some(v) = self.num_files.checked_add(1) {
-            self.num_files = v;
-        } else {
-            eprintln!("Number of files processed exceeds {}", u32::MAX);
-            process::exit(2);
-        }
+        self.num_files = self.num_files.checked_add(1).unwrap_or_else(|| {
+            eprintln!("Number of files processed exceeds {}", u32::MAX);
+            // Prefer: change API to Result and propagate instead of exiting.
+            panic!("FileId overflow");
+        });

If you’re open to a breaking change, switch return type to Result<u32, DupliError> and propagate.

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	pub fn register_file(&mut self, file_name: Arc<String>) -> Option<u32> {
	if self.name_to_index.contains_key(&file_name) {
	return None;
	}
	let num = self.num_files;
	self.index_to_name.push(Arc::clone(&file_name));
	self.name_to_index
	.insert(Arc::clone(&file_name), self.num_files);
	if let Some(v) = self.num_files.checked_add(1) {
	self.num_files = v;
	} else {
	eprintln!("Number of files processed exceeds {}", u32::MAX);
	process::exit(2);
	}
	Some(num)
	}
	pub fn register_file(&mut self, file_name: Arc<String>) -> Option<u32> {
	if self.name_to_index.contains_key(&file_name) {
	return None;
	}
	let num = self.num_files;
	self.index_to_name.push(Arc::clone(&file_name));
	self.name_to_index
	.insert(Arc::clone(&file_name), self.num_files);
	self.num_files = self.num_files.checked_add(1).unwrap_or_else(|| {
	eprintln!("Number of files processed exceeds {}", u32::MAX);
	// Prefer: change API to Result and propagate instead of exiting.
	panic!("FileId overflow");
	});
	Some(num)
	}

🤖 Prompt for AI Agents

In src/lib.rs around lines 602 to 618, the function currently calls
process::exit on num_files overflow which aborts the entire process; change it
to return an error instead of exiting: update the signature to return
Result<u32, DupliError> (or, if you must avoid a breaking change, return
Option<u32> and treat overflow as None), add a new DupliError variant for
"FileIdOverflow" (or reuse an existing error type), replace the process::exit
branch with returning Err(DupliError::FileIdOverflow) (or None), and update all
callers to propagate or handle the Result appropriately (use ? where possible)
so embedders can decide how to handle overflow.

[coderabbitai]

⚠️ Potential issue

Don’t panic if the global Rayon pool is already initialized

build_global() will Err if any Rayon use happened earlier; expect(...) will abort the program. Handle gracefully and continue with the existing pool.

-        if opts.threads != 0 {
-            ThreadPoolBuilder::new()
-                .num_threads(opts.threads)
-                .build_global()
-                .expect("Failed to build global thread pool");
-        }
+        if opts.threads != 0 {
+            if let Err(e) = ThreadPoolBuilder::new()
+                .num_threads(opts.threads)
+                .build_global()
+            {
+                eprintln!("WARNING: Unable to set Rayon global thread pool (already initialized?): {e}");
+            }
+        }

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	if opts.threads != 0 {
	rayon::ThreadPoolBuilder::new()
	ThreadPoolBuilder::new()
	.num_threads(opts.threads)
	.build_global()
	.unwrap();
	.expect("Failed to build global thread pool");
	}
	if opts.threads != 0 {
	if let Err(e) = ThreadPoolBuilder::new()
	.num_threads(opts.threads)
	.build_global()
	{
	eprintln!("WARNING: Unable to set Rayon global thread pool (already initialized?): {e}");
	}
	}

🤖 Prompt for AI Agents

In src/main.rs around lines 66 to 71, the call to
ThreadPoolBuilder::new().num_threads(...).build_global().expect(...) panics if
the global Rayon pool is already initialized; replace the expect with error
handling that treats an Err as non-fatal. Call build_global(), match or if-let
on the Result, and on Ok do nothing, but on Err log a debug/warn that the global
pool was already initialized (or otherwise failed to install) and continue
without aborting; ensure the program does not panic when Rayon reports the pool
is already set up.

[coderabbitai]

🛠️ Refactor suggestion

Propagate reporting errors instead of exiting inside the library

process_report currently calls process::exit(1) on failures. Prefer returning Result from the library and handling exit here.

Apply these diffs (lib + main):

In src/lib.rs:

-pub fn process_report(
+pub fn process_report(
     results_hash: DashMap<u64, Collision>,
     opts: &Options,
     ignore_hashes: &HashMap<u64, bool>,
-) {
+) -> Result<()> {
@@
-    if let Err(e) = print_report(&printable_results, opts, ignore_hashes) {
-        eprintln!("ERROR: Failed to print report: {}", e);
-        process::exit(1);
-    }
+    print_report(&printable_results, opts, ignore_hashes)?;
-}
+    Ok(())
+}

In src/main.rs:

-        process_report(results_hash, &opts, &ignore_hash);
+        if let Err(e) = process_report(results_hash, &opts, &ignore_hash) {
+            eprintln!("ERROR: Failed to print report: {e}");
+            std::process::exit(1);
+        }

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	let results_hash = match process_files(&opts) {
	Ok(results) => results,
	Err(e) => {
	eprintln!("ERROR: Failed to process files: {}", e);
	std::process::exit(1);
	}
	};
	process_report(results_hash, &opts, &ignore_hash);
	}
	let results_hash = match process_files(&opts) {
	Ok(results) => results,
	Err(e) => {
	eprintln!("ERROR: Failed to process files: {}", e);
	std::process::exit(1);
	}
	};
	if let Err(e) = process_report(results_hash, &opts, &ignore_hash) {
	eprintln!("ERROR: Failed to print report: {e}");
	std::process::exit(1);
	}
	}

🤖 Prompt for AI Agents

In src/main.rs around lines 83 to 91, main currently calls
process_report(results_hash, &opts, &ignore_hash) while process_report may call
process::exit(1) inside the library; change the library (src/lib.rs) so
process_report returns a Result<(), Error> instead of exiting, then update main
to match on that Result and, on Err(e), print an error (eprintln!("ERROR: Failed
to generate report: {}", e)) and call std::process::exit(1); ensure
process_report's signature is updated, propagate errors from any internal
operations using ? or map_err, and remove any direct process::exit calls from
the library so the binary handles termination.

[coderabbitai]

⚠️ Potential issue

Strengthen expectation: no collision when first elements differ

maximize_collision should return None when rolling-hash digest was a false positive. This avoids 0-line “collisions”.

-    let collision = maximize_collision(&file_hashes, &left, &right, 2);
-    // Since the first elements are different (1 != 6), there should be no collision
-    // but maximize_collision might still return a collision with 0 lines
-    if let Some(collision) = collision {
-        assert_eq!(collision.num_lines, 0);
-    }
+    let collision = maximize_collision(&file_hashes, &left, &right, 2);
+    assert!(collision.is_none());

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	// Test completely different sequences
	let file_hashes = vec![vec![1, 2, 3, 4, 5], vec![6, 7, 8, 9, 10]];
	let left = LineId {
	file_id: 0,
	line_number: 0,
	};
	let right = LineId {
	file_id: 1,
	line_number: 0,
	};
	let collision = maximize_collision(&file_hashes, &left, &right, 2);
	// Since the first elements are different (1 != 6), there should be no collision
	// but maximize_collision might still return a collision with 0 lines
	if let Some(collision) = collision {
	assert_eq!(collision.num_lines, 0);
	}
	}
	// Test completely different sequences
	let file_hashes = vec![vec![1, 2, 3, 4, 5], vec![6, 7, 8, 9, 10]];
	let left = LineId {
	file_id: 0,
	line_number: 0,
	};
	let right = LineId {
	file_id: 1,
	line_number: 0,
	};
	let collision = maximize_collision(&file_hashes, &left, &right, 2);
	assert!(collision.is_none());
	}

🤖 Prompt for AI Agents

In tests/integration_tests.rs around lines 309 to 327, the test currently allows
maximize_collision to return Some with num_lines == 0 when first elements
differ; instead assert that no collision is returned. Change the assertion to
require collision.is_none() (i.e., fail the test if maximize_collision returns
Some), ensuring the test expects None rather than a zero-length collision.