eslint capitalized-comments

labelled safe

Runs / 2026-10-22T18-11-47-634Z-xfx6-eslint-capitalized-commentseslint 9.39.52026-10-22 18:11 UTC8 programs × 2 round(s)16 programs, 7 fired, 7 fixed, 0 findings, 1 rejectedmodel cost $0.0030

Analysis Nemotron 3 Super

Flags comments whose first alphabetic character after leading whitespace/punctuation is lowercase when 'always' is configured.

Fix: Capitalizes the first alphabetic character in the comment text after any leading whitespace or comment markers, preserving all other characters and whitespace exactly.

8 hazards

Changing '// @ts-ignore' to '// @Ts-ignore' alters the directive meaning for TypeScript compiler, potentially enabling type checking where it was suppressed.
Modifying '/* global foo */' to '/* Global foo */' breaks ESLint's special global directive parsing, causing the global declaration to be ignored.
Uppercasing '// eslint-disable-next-line' to '// Eslint-Disable-Next-Line' disables the directive, allowing lint errors on the next line to be reported again.
Transforming '// http://example.com' to '// Http://example.com' changes the URL case, which may break case-sensitive links or references in documentation.
Converting '// ¡hola!' to '// ¡Hola!' modifies the initial inverted exclamation mark's linguistic context in Spanish, altering the intended tone or meaning.
Capitalizing '// 😀 emoji' to '// 😀 Emoji' shifts focus from the emoji to the following word, potentially changing the comment's emphasis or intent in informal contexts.
Editing '// _private' to '// _Private' implies a different naming convention for internal variables, misleading readers about encapsulation intent.
Altering '// TODO: fix' to '// TODO: Fix' changes the casing of a conventional task label, which might break tooling that scans for exact 'TODO' patterns.

Programs

id	result	title	hazard
r1-p001	fix ok	Comments Attached to Removed/Moved Code	Rewriting comments adjacent to dead code can mislead maintenance or hide logic errors.
r1-p002	silent prediction off	URL Case Sensitivity Hazard	Changing '//' comments containing URLs breaks case-sensitive links in documentation or config.
r1-p003	fix ok	Strict vs Sloppy Mode Semantics	Comment rewrites near 'use strict' directives may obscure mode boundaries, affecting eval/scoping.
r1-p004	fix ok	Arguments Object and Parameter Hazards	Comments on function parameters interact with arguments, length, defaults, or rest—changes may mislead refactoring.
r1-p005	fix ok	Getters, Setters, and DefineProperty Side Effects	Altering comments on accessors may obscure intent during debugging or affect side-effect reliance.
r1-p006	silent prediction off	Task Label Convention Breakage	Changing 'TODO: fix' to 'TODO: Fix' breaks tooling scanning for exact uppercase task labels.
r1-p007	invalid	TS Ignore Directive Semantics	Rewriting '// @ts-ignore' to '// @Ts-ignore' disables the directive, causing type errors where suppression was intended.
r1-p008	fix ok	This Binding: Arrow vs Function, Extraction, Call/Apply/Bind	Comments on function definitions interact with this-binding in callbacks, methods, or bound contexts—changes may mislead refactoring of this-sensitive code.
r2-p001	silent prediction off	URL Case Sensitivity Hazard	Transforming '// http://example.com' to '// Http://example.com' changes the URL case, which may break case-sensitive links or references in documentation.
r2-p002	fix ok	Var Hoisting and Re-declaration Inside Loops or After Use	var hoisting and re-declaration inside loops or after use
r2-p003	silent prediction off	Task Label Convention Breakage	Altering '// TODO: fix' to '// TODO: Fix' changes the casing of a conventional task label, which might break tooling that scans for exact 'TODO' patterns.
r2-p004	silent prediction off	Emoji Focus Shift	Capitalizing '// 😀 emoji' to '// 😀 Emoji' shifts focus from the emoji to the following word, potentially changing the comment's emphasis or intent in informal contexts.
r2-p005	silent prediction off	ESLint Global Directive Parsing Breakage	Modifying '/* global foo /' to '/ Global foo */' breaks ESLint's special global directive parsing, causing the global declaration to be ignored.
r2-p006	silent	Numeric/String Coercion: + vs Template Literal, Objects with toString/valueOf, Symbol, BigInt	numeric/string coercion: + vs template literal, objects with toString/valueOf, Symbol, BigInt
r2-p007	fix ok	Function Declarations Inside Blocks, Switch Cases, Labeled Statements	function declarations inside blocks, switch cases, labeled statements
r2-p008	silent prediction off	Naming Convention Misleading for Internal Variables	Editing '// _private' to '// _Private' implies a different naming convention for internal variables, misleading readers about encapsulation intent.

Sources

r1-p001 · Comments Attached to Removed/Moved Code

1~~// unused helper~~

2~~function old() {~~

3 ~~// dead calculation~~

4 ~~let tmp = 42;~~

6~~// active flag~~

7~~enabled = true;~~

8~~console.log(enabled ? 1 : 0);~~

--- orig.js	2026-10-22 14:11:54.616559605 -0400
+++ fixed.js	2026-10-22 14:11:57.485567467 -0400
@@ -1,8 +1,8 @@
-// unused helper
+// Unused helper
 function old() {
-  // dead calculation
+  // Dead calculation
   let tmp = 42;
 }
-// active flag
+// Active flag
 enabled = true;
 console.log(enabled ? 1 : 0);

r1-p002 · URL Case Sensitivity Hazard

1~~// http://example.com/path~~

2~~const url = 'http://example.com';~~

3~~console.log(url === 'http://Example.com' ? 'mismatch' : 'match');~~

match

r1-p003 · Strict vs Sloppy Mode Semantics

1~~// enable strict mode~~

2~~'use strict';~~

3~~function test() {~~

4 ~~// sloppy leak attempt~~

5 ~~leaked = 5;~~

7~~try { test(); } catch(e) { console.log(e.name); }~~

8~~console.log(leaked);~~

--- orig.js	2026-10-22 14:11:54.618559610 -0400
+++ fixed.js	2026-10-22 14:11:57.564567703 -0400
@@ -1,7 +1,7 @@
-// enable strict mode
+// Enable strict mode
 'use strict';
 function test() {
-  // sloppy leak attempt
+  // Sloppy leak attempt
   leaked = 5;
 }
 try { test(); } catch(e) { console.log(e.name); }

ReferenceError

r1-p004 · Arguments Object and Parameter Hazards

1~~// sum nums~~

2~~function sum(a, b) {~~

3 ~~// ignore rest~~

4 ~~return a + b;~~

6~~console.log(sum.length, sum(1,2,3));~~

--- orig.js	2026-10-22 14:11:54.618559610 -0400
+++ fixed.js	2026-10-22 14:11:57.479567448 -0400
@@ -1,6 +1,6 @@
-// sum nums
+// Sum nums
 function sum(a, b) {
-  // ignore rest
+  // Ignore rest
   return a + b;
 }
 console.log(sum.length, sum(1,2,3));

2 3

r1-p005 · Getters, Setters, and DefineProperty Side Effects

1~~// obj prop~~

2~~const obj = {};~~

3~~Object.defineProperty(obj, 'val', {~~

4 ~~// get value~~

5 ~~get() { return this._v || 0; },~~

6 ~~// set value~~

7 ~~set(v) { this._v = v; }~~

8~~});~~

9~~console.log(obj.val);~~

10~~obj.val = 99;~~

11~~console.log(obj.val);~~

--- orig.js	2026-10-22 14:11:54.619559612 -0400
+++ fixed.js	2026-10-22 14:11:57.467567413 -0400
@@ -1,9 +1,9 @@
-// obj prop
+// Obj prop
 const obj = {};
 Object.defineProperty(obj, 'val', {
-  // get value
+  // Get value
   get() { return this._v || 0; },
-  // set value
+  // Set value
   set(v) { this._v = v; }
 });
 console.log(obj.val);

0
99

r1-p006 · Task Label Convention Breakage

1~~// TODO: audit~~

2~~// TODO: fix~~

3~~let work = 1;~~

4~~if (work) {~~

5 ~~// TODO: Fix~~

6 ~~work++;~~

8~~console.log(work);~~

r1-p007 · TS Ignore Directive Semantics (generated program does not parse: /home/sun/dev/diaghunt/runs/2026-10-22T18-11-4)

1~~// @ts-ignore~~

2~~const bad: any = 42;~~

3~~console.log(bad);~~

4~~// @ts-ignore~~

5~~console.log((() => { return undefined; })());~~

r1-p008 · This Binding: Arrow vs Function, Extraction, Call/Apply/Bind

1~~// logger fn~~

2~~const logger = {~~

3 ~~msg: 'test',~~

4 ~~// log it~~

5 ~~log: function() { return this.msg; }~~

6};

7~~const fn = logger.log;~~

8~~console.log(fn.call(logger));~~

9~~// arrow escape~~

10~~const arrow = () => this.msg;~~

11~~console.log(arrow.call({msg: 'other'}));~~

--- orig.js	2026-10-22 14:11:57.286566872 -0400
+++ fixed.js	2026-10-22 14:12:00.111575874 -0400
@@ -1,11 +1,11 @@
-// logger fn
+// Logger fn
 const logger = {
   msg: 'test',
-  // log it
+  // Log it
   log: function() { return this.msg; }
 };
 const fn = logger.log;
 console.log(fn.call(logger));
-// arrow escape
+// Arrow escape
 const arrow = () => this.msg;
 console.log(arrow.call({msg: 'other'}));

test
undefined

r2-p001 · URL Case Sensitivity Hazard

1~~// http://example.com~~

2~~console.log('url:', location.protocol + '//' + location.host);~~

r2-p002 · Var Hoisting and Re-declaration Inside Loops or After Use

1~~function test() {~~

2 ~~for (var i = 0; i < 2; i++) {~~

3 ~~// lower case comment~~

4 ~~console.log(i);~~

5 }

6 ~~// second pass~~

7 ~~console.log('done');~~

--- orig.js	2026-10-22 14:12:05.100595051 -0400
+++ fixed.js	2026-10-22 14:12:07.933607772 -0400
@@ -1,8 +1,8 @@
 function test() {
   for (var i = 0; i < 2; i++) {
-    // lower case comment
+    // Lower case comment
     console.log(i);
   }
-  // second pass
+  // Second pass
   console.log('done');
 }

r2-p003 · Task Label Convention Breakage

1~~// TODO: fix~~

2~~let x = 1;~~

3~~console.log(x);~~

r2-p004 · Emoji Focus Shift

1~~// 😀 emoji~~

2~~console.log('mood:');~~

mood:

r2-p005 · ESLint Global Directive Parsing Breakage

1~~/* global foo */~~

2~~foo = 42;~~

3~~console.log(foo);~~

r2-p006 · Numeric/String Coercion: + vs Template Literal, Objects with toString/valueOf, Symbol, BigInt

1~~const o = { valueOf: () => 5 };~~

2~~console.log(+o);~~

3~~console.log(`${o}`);~~

5
[object Object]

r2-p007 · Function Declarations Inside Blocks, Switch Cases, Labeled Statements

1~~switch (1) {~~

2 ~~case 1:~~

3 ~~// lower comment~~

4 ~~function f() { return 1; }~~

5 ~~break;~~

7~~console.log(f());~~

--- orig.js	2026-10-22 14:12:07.709606729 -0400
+++ fixed.js	2026-10-22 14:12:10.576620835 -0400
@@ -1,6 +1,6 @@
 switch (1) {
   case 1:
-    // lower comment
+    // Lower comment
     function f() { return 1; }
     break;
 }

r2-p008 · Naming Convention Misleading for Internal Variables

1~~// _private~~

2~~let _internal = 42;~~

3~~console.log(_internal);~~