Repository navigation
util.inspect() ignores breakLength: Infinity when depth: Infinity is also set in some cases #60475
Description
Version
v25.1.0
Platform
- Windows: Microsoft Windows NT 10.0.26200.0 x64
- macOS: Darwin MacBook-Pro.local 24.6.0 Darwin Kernel Version 24.6.0: Mon Jul 14 11:30:51 PDT 2025; root:xnu-11417.140.69~1/RELEASE_ARM64_T8112 arm64
- Linux: Linux myhost 6.8.0-45-generic #45-Ubuntu SMP PREEMPT_DYNAMIC x86_64 GNU/Linux
Subsystem
util
What steps will reproduce the bug?
When util.inspect() is called with both breakLength: Infinity and depth: Infinity, the output unexpectedly contains line breaks in Node.js v25.x.
In contrast:
- Using only
breakLength: Infinity(with defaultdepth) works correctly and produces a single-line output. - The issue appears only when
depthis explicitly set toInfinity.
This behavior did not occur in Node.js v24.x, so it appears to be a regression.
A minimal reproducible example is provided below.
$ nvm use 24
Now using node v24.11.0 (npm v11.6.1)
$ node
Welcome to Node.js v24.11.0.
Type ".help" for more information.
> const util = require("node:util")
undefined
> util.inspect(util, { breakLength: Infinity })
"{ _errnoException: [Function: _errnoException], _exceptionWithHostPort: [Function: _exceptionWithHostPort], _extend: [Function: deprecated], callbackify: [Function: callbackify], debug: [Function: debuglog], debuglog: [Function: debuglog], deprecate: [Function: deprecate], format: [Function: format], styleText: [Function: styleText], formatWithOptions: [Function: formatWithOptions], getCallSites: [Function: getCallSites], getSystemErrorMap: [Function: getSystemErrorMap], getSystemErrorName: [Function: getSystemErrorName], getSystemErrorMessage: [Function: getSystemErrorMessage], inherits: [Function: inherits], inspect: [Function: inspect] { custom: Symbol(nodejs.util.inspect.custom), colors: [Object: null prototype] { reset: [Array], bold: [Array], dim: [Array], italic: [Array], underline: [Array], blink: [Array], inverse: [Array], hidden: [Array], strikethrough: [Array], doubleunderline: [Array], black: [Array], red: [Array], green: [Array], yellow: [Array], blue: [Array], magenta: [Array], cyan: [Array], white: [Array], bgBlack: [Array], bgRed: [Array], bgGreen: [Array], bgYellow: [Array], bgBlue: [Array], bgMagenta: [Array], bgCyan: [Array], bgWhite: [Array], framed: [Array], overlined: [Array], gray: [Array], redBright: [Array], greenBright: [Array], yellowBright: [Array], blueBright: [Array], magentaBright: [Array], cyanBright: [Array], whiteBright: [Array], bgGray: [Array], bgRedBright: [Array], bgGreenBright: [Array], bgYellowBright: [Array], bgBlueBright: [Array], bgMagentaBright: [Array], bgCyanBright: [Array], bgWhiteBright: [Array] }, styles: [Object: null prototype] { special: 'cyan', number: 'yellow', bigint: 'yellow', boolean: 'yellow', undefined: 'grey', null: 'bold', string: 'green', symbol: 'green', date: 'magenta', regexp: 'red', module: 'underline' }, replDefaults: [Getter/Setter] }, isArray: [Function: deprecated], isDeepStrictEqual: [Function: isDeepStrictEqual], promisify: [Function: promisify] { custom: Symbol(nodejs.util.promisify.custom) }, stripVTControlCharacters: [Function: stripVTControlCharacters], toUSVString: [Function: toUSVString], transferableAbortSignal: [Getter], transferableAbortController: [Getter], aborted: [Getter], types: { isArgumentsObject: [Function (anonymous)], isArrayBuffer: [Function (anonymous)], isAsyncFunction: [Function (anonymous)], isBigIntObject: [Function (anonymous)], isBooleanObject: [Function (anonymous)], isDataView: [Function (anonymous)], isDate: [Function (anonymous)], isExternal: [Function (anonymous)], isGeneratorFunction: [Function (anonymous)], isGeneratorObject: [Function (anonymous)], isMap: [Function (anonymous)], isMapIterator: [Function (anonymous)], isModuleNamespaceObject: [Function (anonymous)], isNativeError: [Function (anonymous)], isNumberObject: [Function (anonymous)], isPromise: [Function (anonymous)], isProxy: [Function (anonymous)], isRegExp: [Function (anonymous)], isSet: [Function (anonymous)], isSetIterator: [Function (anonymous)], isSharedArrayBuffer: [Function (anonymous)], isStringObject: [Function (anonymous)], isSymbolObject: [Function (anonymous)], isWeakMap: [Function (anonymous)], isWeakSet: [Function (anonymous)], isAnyArrayBuffer: [Function (anonymous)], isBoxedPrimitive: [Function (anonymous)], isArrayBufferView: [Function: isView], isTypedArray: [Function: isTypedArray], isUint8Array: [Function: isUint8Array], isUint8ClampedArray: [Function: isUint8ClampedArray], isUint16Array: [Function: isUint16Array], isUint32Array: [Function: isUint32Array], isInt8Array: [Function: isInt8Array], isInt16Array: [Function: isInt16Array], isInt32Array: [Function: isInt32Array], isFloat16Array: [Function: isFloat16Array], isFloat32Array: [Function: isFloat32Array], isFloat64Array: [Function: isFloat64Array], isBigInt64Array: [Function: isBigInt64Array], isBigUint64Array: [Function: isBigUint64Array], isKeyObject: [Function: value], isCryptoKey: [Function: value] }, parseEnv: [Function: parseEnv], parseArgs: [Function: parseArgs], TextDecoder: [class TextDecoder], TextEncoder: [class TextEncoder], MIMEType: [class MIMEType], MIMEParams: [class MIMEParams], diff: [Function: diff], setTraceSigInt: [Function: setTraceSigInt] }"
> util.inspect(util, { breakLength: Infinity, depth: Infinity })
"{ _errnoException: [Function: _errnoException], _exceptionWithHostPort: [Function: _exceptionWithHostPort], _extend: [Function: deprecated], callbackify: [Function: callbackify], debug: [Function: debuglog], debuglog: [Function: debuglog], deprecate: [Function: deprecate], format: [Function: format], styleText: [Function: styleText], formatWithOptions: [Function: formatWithOptions], getCallSites: [Function: getCallSites], getSystemErrorMap: [Function: getSystemErrorMap], getSystemErrorName: [Function: getSystemErrorName], getSystemErrorMessage: [Function: getSystemErrorMessage], inherits: [Function: inherits], inspect: [Function: inspect] { custom: Symbol(nodejs.util.inspect.custom), colors: [Object: null prototype] { reset: [ 0, 0 ], bold: [ 1, 22 ], dim: [ 2, 22 ], italic: [ 3, 23 ], underline: [ 4, 24 ], blink: [ 5, 25 ], inverse: [ 7, 27 ], hidden: [ 8, 28 ], strikethrough: [ 9, 29 ], doubleunderline: [ 21, 24 ], black: [ 30, 39 ], red: [ 31, 39 ], green: [ 32, 39 ], yellow: [ 33, 39 ], blue: [ 34, 39 ], magenta: [ 35, 39 ], cyan: [ 36, 39 ], white: [ 37, 39 ], bgBlack: [ 40, 49 ], bgRed: [ 41, 49 ], bgGreen: [ 42, 49 ], bgYellow: [ 43, 49 ], bgBlue: [ 44, 49 ], bgMagenta: [ 45, 49 ], bgCyan: [ 46, 49 ], bgWhite: [ 47, 49 ], framed: [ 51, 54 ], overlined: [ 53, 55 ], gray: [ 90, 39 ], redBright: [ 91, 39 ], greenBright: [ 92, 39 ], yellowBright: [ 93, 39 ], blueBright: [ 94, 39 ], magentaBright: [ 95, 39 ], cyanBright: [ 96, 39 ], whiteBright: [ 97, 39 ], bgGray: [ 100, 49 ], bgRedBright: [ 101, 49 ], bgGreenBright: [ 102, 49 ], bgYellowBright: [ 103, 49 ], bgBlueBright: [ 104, 49 ], bgMagentaBright: [ 105, 49 ], bgCyanBright: [ 106, 49 ], bgWhiteBright: [ 107, 49 ] }, styles: [Object: null prototype] { special: 'cyan', number: 'yellow', bigint: 'yellow', boolean: 'yellow', undefined: 'grey', null: 'bold', string: 'green', symbol: 'green', date: 'magenta', regexp: 'red', module: 'underline' }, replDefaults: [Getter/Setter] }, isArray: [Function: deprecated], isDeepStrictEqual: [Function: isDeepStrictEqual], promisify: [Function: promisify] { custom: Symbol(nodejs.util.promisify.custom) }, stripVTControlCharacters: [Function: stripVTControlCharacters], toUSVString: [Function: toUSVString], transferableAbortSignal: [Getter], transferableAbortController: [Getter], aborted: [Getter], types: { isArgumentsObject: [Function (anonymous)], isArrayBuffer: [Function (anonymous)], isAsyncFunction: [Function (anonymous)], isBigIntObject: [Function (anonymous)], isBooleanObject: [Function (anonymous)], isDataView: [Function (anonymous)], isDate: [Function (anonymous)], isExternal: [Function (anonymous)], isGeneratorFunction: [Function (anonymous)], isGeneratorObject: [Function (anonymous)], isMap: [Function (anonymous)], isMapIterator: [Function (anonymous)], isModuleNamespaceObject: [Function (anonymous)], isNativeError: [Function (anonymous)], isNumberObject: [Function (anonymous)], isPromise: [Function (anonymous)], isProxy: [Function (anonymous)], isRegExp: [Function (anonymous)], isSet: [Function (anonymous)], isSetIterator: [Function (anonymous)], isSharedArrayBuffer: [Function (anonymous)], isStringObject: [Function (anonymous)], isSymbolObject: [Function (anonymous)], isWeakMap: [Function (anonymous)], isWeakSet: [Function (anonymous)], isAnyArrayBuffer: [Function (anonymous)], isBoxedPrimitive: [Function (anonymous)], isArrayBufferView: [Function: isView], isTypedArray: [Function: isTypedArray], isUint8Array: [Function: isUint8Array], isUint8ClampedArray: [Function: isUint8ClampedArray], isUint16Array: [Function: isUint16Array], isUint32Array: [Function: isUint32Array], isInt8Array: [Function: isInt8Array], isInt16Array: [Function: isInt16Array], isInt32Array: [Function: isInt32Array], isFloat16Array: [Function: isFloat16Array], isFloat32Array: [Function: isFloat32Array], isFloat64Array: [Function: isFloat64Array], isBigInt64Array: [Function: isBigInt64Array], isBigUint64Array: [Function: isBigUint64Array], isKeyObject: [Function: value], isCryptoKey: [Function: value] }, parseEnv: [Function: parseEnv], parseArgs: [Function: parseArgs], TextDecoder: [class TextDecoder], TextEncoder: [class TextEncoder], MIMEType: [class MIMEType], MIMEParams: [class MIMEParams], diff: [Function: diff], setTraceSigInt: [Function: setTraceSigInt] }"
>
$ nvm use 25
Now using node v25.1.0 (npm v11.6.2)
$ node
Welcome to Node.js v25.1.0.
Type ".help" for more information.
> const util = require("node:util")
undefined
> util.inspect(util, { breakLength: Infinity })
"{ _errnoException: [Function: _errnoException], _exceptionWithHostPort: [Function: _exceptionWithHostPort], _extend: [Function: deprecated], callbackify: [Function: callbackify], debug: [Function: debuglog], debuglog: [Function: debuglog], deprecate: [Function: deprecate], format: [Function: format], styleText: [Function: styleText], formatWithOptions: [Function: formatWithOptions], getCallSites: [Function: getCallSites], getSystemErrorMap: [Function: getSystemErrorMap], getSystemErrorName: [Function: getSystemErrorName], getSystemErrorMessage: [Function: getSystemErrorMessage], inherits: [Function: inherits], inspect: [Function: inspect] { custom: Symbol(nodejs.util.inspect.custom), colors: [Object: null prototype] { reset: [Array], bold: [Array], dim: [Array], italic: [Array], underline: [Array], blink: [Array], inverse: [Array], hidden: [Array], strikethrough: [Array], doubleunderline: [Array], black: [Array], red: [Array], green: [Array], yellow: [Array], blue: [Array], magenta: [Array], cyan: [Array], white: [Array], bgBlack: [Array], bgRed: [Array], bgGreen: [Array], bgYellow: [Array], bgBlue: [Array], bgMagenta: [Array], bgCyan: [Array], bgWhite: [Array], framed: [Array], overlined: [Array], gray: [Array], redBright: [Array], greenBright: [Array], yellowBright: [Array], blueBright: [Array], magentaBright: [Array], cyanBright: [Array], whiteBright: [Array], bgGray: [Array], bgRedBright: [Array], bgGreenBright: [Array], bgYellowBright: [Array], bgBlueBright: [Array], bgMagentaBright: [Array], bgCyanBright: [Array], bgWhiteBright: [Array] }, styles: [Object: null prototype] { special: 'cyan', number: 'yellow', bigint: 'yellow', boolean: 'yellow', undefined: 'grey', null: 'bold', string: 'green', symbol: 'green', date: 'magenta', regexp: [Function], module: 'underline' }, replDefaults: [Getter/Setter] }, isArray: [Function: deprecated], isDeepStrictEqual: [Function: isDeepStrictEqual], promisify: [Function: promisify] { custom: Symbol(nodejs.util.promisify.custom) }, stripVTControlCharacters: [Function: stripVTControlCharacters], toUSVString: [Function: toUSVString], transferableAbortSignal: [Getter], transferableAbortController: [Getter], aborted: [Getter], types: { isArgumentsObject: [Function (anonymous)], isArrayBuffer: [Function (anonymous)], isAsyncFunction: [Function (anonymous)], isBigIntObject: [Function (anonymous)], isBooleanObject: [Function (anonymous)], isDataView: [Function (anonymous)], isDate: [Function (anonymous)], isExternal: [Function (anonymous)], isGeneratorFunction: [Function (anonymous)], isGeneratorObject: [Function (anonymous)], isMap: [Function (anonymous)], isMapIterator: [Function (anonymous)], isModuleNamespaceObject: [Function (anonymous)], isNativeError: [Function (anonymous)], isNumberObject: [Function (anonymous)], isPromise: [Function (anonymous)], isProxy: [Function (anonymous)], isRegExp: [Function (anonymous)], isSet: [Function (anonymous)], isSetIterator: [Function (anonymous)], isSharedArrayBuffer: [Function (anonymous)], isStringObject: [Function (anonymous)], isSymbolObject: [Function (anonymous)], isWeakMap: [Function (anonymous)], isWeakSet: [Function (anonymous)], isAnyArrayBuffer: [Function (anonymous)], isBoxedPrimitive: [Function (anonymous)], isArrayBufferView: [Function: isView], isTypedArray: [Function: isTypedArray], isUint8Array: [Function: isUint8Array], isUint8ClampedArray: [Function: isUint8ClampedArray], isUint16Array: [Function: isUint16Array], isUint32Array: [Function: isUint32Array], isInt8Array: [Function: isInt8Array], isInt16Array: [Function: isInt16Array], isInt32Array: [Function: isInt32Array], isFloat16Array: [Function: isFloat16Array], isFloat32Array: [Function: isFloat32Array], isFloat64Array: [Function: isFloat64Array], isBigInt64Array: [Function: isBigInt64Array], isBigUint64Array: [Function: isBigUint64Array], isKeyObject: [Function: value], isCryptoKey: [Function: value] }, parseEnv: [Function: parseEnv], parseArgs: [Function: parseArgs], TextDecoder: [class TextDecoder], TextEncoder: [class TextEncoder], MIMEType: [class MIMEType], MIMEParams: [class MIMEParams], diff: [Function: diff], setTraceSigInt: [Function: setTraceSigInt] }"
> util.inspect(util, { breakLength: Infinity, depth: Infinity })
'{\n' +
' _errnoException: [Function: _errnoException],\n' +
' _exceptionWithHostPort: [Function: _exceptionWithHostPort],\n' +
' _extend: [Function: deprecated],\n' +
' callbackify: [Function: callbackify],\n' +
' debug: [Function: debuglog],\n' +
' debuglog: [Function: debuglog],\n' +
' deprecate: [Function: deprecate],\n' +
' format: [Function: format],\n' +
' styleText: [Function: styleText],\n' +
' formatWithOptions: [Function: formatWithOptions],\n' +
' getCallSites: [Function: getCallSites],\n' +
' getSystemErrorMap: [Function: getSystemErrorMap],\n' +
' getSystemErrorName: [Function: getSystemErrorName],\n' +
' getSystemErrorMessage: [Function: getSystemErrorMessage],\n' +
' inherits: [Function: inherits],\n' +
' inspect: [Function: inspect] {\n' +
' custom: Symbol(nodejs.util.inspect.custom),\n' +
' colors: [Object: null prototype] { reset: [ 0, 0 ], bold: [ 1, 22 ], dim: [ 2, 22 ], italic: [ 3, 23 ], underline: [ 4, 24 ], blink: [ 5, 25 ], inverse: [ 7, 27 ], hidden: [ 8, 28 ], strikethrough: [ 9, 29 ], doubleunderline: [ 21, 24 ], black: [ 30, 39 ], red: [ 31, 39 ], green: [ 32, 39 ], yellow: [ 33, 39 ], blue: [ 34, 39 ], magenta: [ 35, 39 ], cyan: [ 36, 39 ], white: [ 37, 39 ], bgBlack: [ 40, 49 ], bgRed: [ 41, 49 ], bgGreen: [ 42, 49 ], bgYellow: [ 43, 49 ], bgBlue: [ 44, 49 ], bgMagenta: [ 45, 49 ], bgCyan: [ 46, 49 ], bgWhite: [ 47, 49 ], framed: [ 51, 54 ], overlined: [ 53, 55 ], gray: [ 90, 39 ], redBright: [ 91, 39 ], greenBright: [ 92, 39 ], yellowBright: [ 93, 39 ], blueBright: [ 94, 39 ], magentaBright: [ 95, 39 ], cyanBright: [ 96, 39 ], whiteBright: [ 97, 39 ], bgGray: [ 100, 49 ], bgRedBright: [ 101, 49 ], bgGreenBright: [ 102, 49 ], bgYellowBright: [ 103, 49 ], bgBlueBright: [ 104, 49 ], bgMagentaBright: [ 105, 49 ], bgCyanBright: [ 106, 49 ], bgWhiteBright: [ 107, 49 ] },\n' +
" styles: [Object: null prototype] { special: 'cyan', number: 'yellow', bigint: 'yellow', boolean: 'yellow', undefined: 'grey', null: 'bold', string: 'green', symbol: 'green', date: 'magenta', regexp: [Function: highlightRegExp] { colors: [ 'green', 'red', 'yellow', 'cyan', 'magenta' ] }, module: 'underline' },\n" +
' replDefaults: [Getter/Setter]\n' +
' },\n' +
' isArray: [Function: deprecated],\n' +
' isDeepStrictEqual: [Function: isDeepStrictEqual],\n' +
' promisify: [Function: promisify] { custom: Symbol(nodejs.util.promisify.custom) },\n' +
' stripVTControlCharacters: [Function: stripVTControlCharacters],\n' +
' toUSVString: [Function: toUSVString],\n' +
' transferableAbortSignal: [Getter],\n' +
' transferableAbortController: [Getter],\n' +
' aborted: [Getter],\n' +
' types: { isArgumentsObject: [Function (anonymous)], isArrayBuffer: [Function (anonymous)], isAsyncFunction: [Function (anonymous)], isBigIntObject: [Function (anonymous)], isBooleanObject: [Function (anonymous)], isDataView: [Function (anonymous)], isDate: [Function (anonymous)], isExternal: [Function (anonymous)], isGeneratorFunction: [Function (anonymous)], isGeneratorObject: [Function (anonymous)], isMap: [Function (anonymous)], isMapIterator: [Function (anonymous)], isModuleNamespaceObject: [Function (anonymous)], isNativeError: [Function (anonymous)], isNumberObject: [Function (anonymous)], isPromise: [Function (anonymous)], isProxy: [Function (anonymous)], isRegExp: [Function (anonymous)], isSet: [Function (anonymous)], isSetIterator: [Function (anonymous)], isSharedArrayBuffer: [Function (anonymous)], isStringObject: [Function (anonymous)], isSymbolObject: [Function (anonymous)], isWeakMap: [Function (anonymous)], isWeakSet: [Function (anonymous)], isAnyArrayBuffer: [Function (anonymous)], isBoxedPrimitive: [Function (anonymous)], isArrayBufferView: [Function: isView], isTypedArray: [Function: isTypedArray], isUint8Array: [Function: isUint8Array], isUint8ClampedArray: [Function: isUint8ClampedArray], isUint16Array: [Function: isUint16Array], isUint32Array: [Function: isUint32Array], isInt8Array: [Function: isInt8Array], isInt16Array: [Function: isInt16Array], isInt32Array: [Function: isInt32Array], isFloat16Array: [Function: isFloat16Array], isFloat32Array: [Function: isFloat32Array], isFloat64Array: [Function: isFloat64Array], isBigInt64Array: [Function: isBigInt64Array], isBigUint64Array: [Function: isBigUint64Array], isKeyObject: [Function: value], isCryptoKey: [Function: value] },\n' +
' parseEnv: [Function: parseEnv],\n' +
' parseArgs: [Function: parseArgs],\n' +
' TextDecoder: [class TextDecoder],\n' +
' TextEncoder: [class TextEncoder],\n' +
' MIMEType: [class MIMEType],\n' +
' MIMEParams: [class MIMEParams],\n' +
' diff: [Function: diff],\n' +
' setTraceSigInt: [Function: setTraceSigInt]\n' +
'}'How often does it reproduce? Is there a required condition?
Always reproducible when both breakLength and depth are set to Infinity.
What is the expected behavior? Why is that the expected behavior?
According to the Node.js documentation:
breakLength <integer>
The length at which input values are split across multiple lines.
Set toInfinityto format the input as a single line (in combination withcompactset totrueor any number >= 1).
Default: 80.
Therefore, when breakLength is set to Infinity, the output should always be rendered as a single line, regardless of object depth or size.
What do you see instead?
The output contains multiple lines with indentation, even though breakLength is set to Infinity.
This happens only when depth is also set to Infinity.
Additional information
No response
Activity
BridgeAR commentedon Oct 29, 2025
I am currently looking into this. It does not seem to be a recent regression, it is just surfacing due to the presence of something that is handled in a way that it causes line breaks. I did not yet identify where the line break comes from.
[-]`util.inspect()` ignores `breakLength: Infinity` when `depth: Infinity` is also set (regression in v25)[/-][+]`util.inspect()` ignores `breakLength: Infinity` when `depth: Infinity` is also set in some cases[/+]Han5991 commentedon Nov 19, 2025
@BridgeAR I’ve opened PR #60783 to ensure util.inspect() honors breakLength: Infinity when depth is also Infinity. Could you please take a look?
KanishkRanjan commentedon Nov 19, 2025
I was working on this is issue as well 😅 (no strong feelings) and I verify that @Han5991 commit fixes this issue
I have noticed that this issue exists in older Node.js versions as well. When you inspect the module using:
you can see the presence of \n even in older versions.
Also:
util.inspect(util, { breakLength: Infinity, depth: Infinity })shows differences between the two versions because of the introduction of highlightRegExp, which was previously non-enumerable (e.g., 'red') in util code itself (inspect.styles )
I wanted to understand this better.
@Han5991 — could you explain how you figured out the solution? I was stuck trying to understand why making it enumerable causes this error.
Han5991 commentedon Nov 19, 2025
I traced the unwanted newlines back to the two places where we decide whether to wrap output:
groupArrayElements()— this tries to fit array entries into columns based on ctx.breakLength.reduceToSingleString()— this is the “compact” heuristic that keeps properties on one line only if the current depth is within the user’s compact limit.Both paths implicitly assumed that ctx.breakLength was finite. When breakLength is Infinity, those calculations still run and end up inserting newlines once you
inspect a deep enough structure (which is why inspecting http or util recreates the issue even on older releases).
The fix was to short-circuit those heuristics whenever the user explicitly sets both breakLength: Infinity and an “unlimited” depth (depth: Infinity or null). In
that configuration the user is effectively saying “never wrap, never truncate,” so we simply bypass the width calculations. Highlighting being enumerable doesn’t
change that behavior — it just makes the inspected object larger so you hit those wrapping heuristics more easily.
util: honor breakLength Infinity with unlimited depth
util: honor breakLength: Infinity for deep objects and arrays
util: fix breakLength: Infinity for deep objects
util: fix breakLength: Infinity for deep objects