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Pull Request check-list

  • Does make -j8 test (UNIX) or vcbuild test nosign (Windows) pass with
    this change (including linting)?
  • Is the commit message formatted according to [CONTRIBUTING.md][0]?
  • If this change fixes a bug (or a performance problem), is a regression
    test (or a benchmark) included?
  • Is a documentation update included (if this change modifies
    existing APIs, or introduces new ones)?

Affected core subsystem(s)

console

Description of change

Based on #3514 discussion, I've removed throw an error in timeEnd() method, if there is no matching label.

if (!stdout || typeof stdout.write !== 'function') {
throw new TypeError('Console expects a writable stream instance');
}
if (!(this instanceof Console)) return new Console(stdout, stderr);
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Please revert these style changes.

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@cjihrig What style guides do you using? Should I revert all the style changes or only this one?

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We have an ESLint setup. But, in general, you should change the bare minimum in your PRs. Otherwise, it makes tools like git blame harder to use.

@ghaiklor
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@cjihrig done

@mscdex mscdex added the console Issues and PRs related to the console subsystem. label Mar 25, 2016
@@ -8,7 +8,8 @@ assert.ok(process.stderr.writable);
assert.equal('number', typeof process.stdout.fd);
assert.equal('number', typeof process.stderr.fd);

assert.throws(function() {
assert.doesNotThrow(function() {
console.time('some label');
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This is unnecessary.

@ghaiklor
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@cjihrig got it, so we can ignore non-existing label.

throw new Error('No such label: ' + label);
}
const time = this._times.get(label);
if (!time) return;
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Can you just replace the old throw with return;. It just needs to be a one line change.

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cjihrig commented Mar 25, 2016

I think so (see #3514 (comment)). What you had before was wrong. It would print something but it had the incorrect times.

@@ -8,10 +8,6 @@ assert.ok(process.stderr.writable);
assert.equal('number', typeof process.stdout.fd);
assert.equal('number', typeof process.stderr.fd);

assert.throws(function() {
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I didn't mean to delete the whole test. Just the one line that I commented on was unnecessary.

@ghaiklor
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@cjihrig here is my code:

var console = require('console');

console.time('test');
console.timeEnd('no such label');
console.timeEnd('test');

Prints only for test label:

./node test.js
test: 0.652ms

The following code:

var console = require('console');
console.timeEnd('no such label');

prints nothing.

}

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Please remove this newly added line.

@cjihrig
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cjihrig commented Mar 25, 2016

LGTM with one comment.

@ghaiklor
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@cjihrig I see now. I must change only lines where it actually needs. Updated.

@cjihrig cjihrig added the semver-major PRs that contain breaking changes and should be released in the next major version. label Mar 25, 2016
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cjihrig commented Mar 25, 2016

@jasnell
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jasnell commented Mar 26, 2016

LGTM

@thefourtheye
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We are doing this so that we would be on par with browsers? It feels like what we are doing is correct. If there is a typo in the name or if the usage is wrong we explicitly throw and let the user know what is wrong.

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jasnell commented Mar 26, 2016

How about a compromise? Don't throw but emit a warning using process.emitWarning.

@ghaiklor
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In case of wrong label you get nothing in the console. That way you will know that you forgot to close console.time(). Looks as expected behaviour for me.

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jasnell commented Apr 18, 2016

@thefourtheye ... do you still object to this or ...?

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Yes, I am still not convinced that this change is better.

To think of it, emitting a warning, as you suggested, would be the right fit here. This is not a serious error, I agree, but there should be some feedback to the user.

if (!time) {
throw new Error('No such label: ' + label);
return;
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@jasnell jasnell Apr 19, 2016

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@ghaiklor ... would it be possible for you to add a ...

process.emitWarning(`No such label: ${label}`);

...before returning here?

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Should we include console.timeEnd somewhere in the message?

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Wouldn't hurt... No such label '${label}' for console.timeEnd() perhaps? Keep in mind, also, that the warning includes a stack trace.

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Ah, then the message is just fine.

@ghaiklor
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@jasnell @thefourtheye yeah, I will update branch in few hours.

@ghaiklor
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Warning doesn't include a stack trace. So I updated message with @jasnell approach.

> console.timeEnd('no label');
> (node:51305) Warning: No such label 'no label' for console.timeEnd()

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jasnell commented Apr 19, 2016

@ghaiklor. It does, it's just suppressed in the default output. If you use the --trace-warnings flag it will print the stack trace. And if you watch for warnings using process.on('warning', function(warn) { /** ... **/ });, the warn object will have a stack property that returns the stack trace.

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jasnell commented Apr 19, 2016

one additional suggestion: in the test case, you can add a check to make sure the warning is issued appropriately... something like...

process.on('warning', common.mustCall((warning) => {
  assert(/No such label 'no label' for console.timeEnd\(\)/.test(warning.message));
}));

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jasnell commented Apr 19, 2016

LGTM with a suggestion.

@ghaiklor
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I've added check for warning event in the test case.

@thefourtheye
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LGTM

console.timeEnd('no such label');

process.nextTick(() => process.removeListener('warning', onWarning));
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just use process.once('warning', onWarning) above and this isn't necessary.

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jasnell commented Apr 20, 2016

couple more nits after adding the warning check

assert.throws(function() {
assert.doesNotThrow(function() {
const message = /No such label 'no such label' for console\.timeEnd\(\)/;
const onWarning = common.mustCall(warning => assert(message.test(warning.message)));
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Does this pass linting?

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It shouldn't. We added a rule where parens are explicitly required I though

@cjihrig
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cjihrig commented Apr 20, 2016

Yea, still LGTM once the comments are addressed.

@ghaiklor
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@cjihrig updated and fixed conflicts with master branch.

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cjihrig commented Apr 21, 2016

It would probably be simpler to use assert.strictEqual() instead of a regular expression in your test, but I don't think it needs to hold this us. Could you squash your changes down to a single commit?

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@cjihrig yes, I can, but I'm not sure if I can push them with force flag. As I understand, I need to do:

git rebase -i master

Squash all commits in one and then

git push --force origin fix/3514

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cjihrig commented Apr 21, 2016

It's fine to force push your own branch. No one else is using it.

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@cjihrig done

const message = /No such label 'no such label' for console\.timeEnd\(\)/;
const onWarning = (warning) => assert(message.test(warning.message));
process.once('warning', common.mustCall(onWarning));

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this could likely be rewritten and simplified to just:

process.once('warning', common.mustCall((warning) => {
  assert(/no such label/.test(warning.message);
});

There's likely very little need to test the entire warning message. You just want to verify that the warning is being issued.

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jasnell commented Apr 21, 2016

Just one last nit while I was looking it back over :-) Looking good!

When timeEnd() provided with label that doesn't exists
it emits warning in the console, so developer get know about it.
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@jasnell done.

BTW, why do I need squash commits by myself if it can be done when merging into master (after rebase)?

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jasnell commented Apr 21, 2016

@ghaiklor ... while it's possible for the person landing the PR to squash everything, it's often easier for those of us who do the landing to have the author of the PR squash them down (typically because it saves time). I personally don't mind squashing commits when I land things.

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jasnell commented Apr 21, 2016

New CI: https://ci.nodejs.org/job/node-test-pull-request/2359/
LGTM if CI is green

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@jasnell I see, thanks for explanation 😃
CI is green, my first contribution ^^

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jasnell commented Apr 21, 2016

Awesome! Thank you for the contribution and for the patience! @cjihrig ... does this LGTY?

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cjihrig commented Apr 21, 2016

:shipit: (yes, LGTM)

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jasnell commented Apr 21, 2016

Awesome. Given that this is a semver-major, let's give time for one more round of last call comments from @nodejs/ctc. If there are no objections by Monday I'll get this landed.

@jasnell jasnell added this to the 6.0.0 milestone Apr 22, 2016
jasnell pushed a commit that referenced this pull request Apr 25, 2016
When timeEnd() provided with label that doesn't exists
it emits warning in the console, so developer get know about it.

PR-URL: #5901
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Sakthipriyan Vairamani <[email protected]>
@jasnell
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jasnell commented Apr 25, 2016

Landed in 1c84579

@jasnell jasnell closed this Apr 25, 2016
joelostrowski pushed a commit to joelostrowski/node that referenced this pull request Apr 25, 2016
When timeEnd() provided with label that doesn't exists
it emits warning in the console, so developer get know about it.

PR-URL: nodejs#5901
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Sakthipriyan Vairamani <[email protected]>
@ghaiklor ghaiklor deleted the fix/3514 branch April 25, 2016 17:37
jasnell pushed a commit that referenced this pull request Apr 26, 2016
When timeEnd() provided with label that doesn't exists
it emits warning in the console, so developer get know about it.

PR-URL: #5901
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Sakthipriyan Vairamani <[email protected]>
antonPiPx pushed a commit to antonPiPx/node that referenced this pull request Aug 7, 2025
# Console

<!--introduced_in=v0.10.13-->

> Stability: 2 - Stable

<!-- source_link=lib/console.js -->

The `node:console` module provides a simple debugging console that is similar to
the JavaScript console mechanism provided by web browsers.

The module exports two specific components:

* A `Console` class with methods such as `console.log()`, `console.error()`, and
  `console.warn()` that can be used to write to any Node.js stream.
* A global `console` instance configured to write to [`process.stdout`][] and
  [`process.stderr`][]. The global `console` can be used without calling
  `require('node:console')`.

_**Warning**_: The global console object's methods are neither consistently
synchronous like the browser APIs they resemble, nor are they consistently
asynchronous like all other Node.js streams. Programs that desire to depend
on the synchronous / asynchronous behavior of the console functions should
first figure out the nature of console's backing stream. This is because the
stream is dependent on the underlying platform and standard stream
configuration of the current process. See the [note on process I/O][] for
more information.

Example using the global `console`:

```js
console.log('hello world');
// Prints: hello world, to stdout
console.log('hello %s', 'world');
// Prints: hello world, to stdout
console.error(new Error('Whoops, something bad happened'));
// Prints error message and stack trace to stderr:
//   Error: Whoops, something bad happened
//     at [eval]:5:15
//     at Script.runInThisContext (node:vm:132:18)
//     at Object.runInThisContext (node:vm:309:38)
//     at node:internal/process/execution:77:19
//     at [eval]-wrapper:6:22
//     at evalScript (node:internal/process/execution:76:60)
//     at node:internal/main/eval_string:23:3

const name = 'Will Robinson';
console.warn(`Danger ${name}! Danger!`);
// Prints: Danger Will Robinson! Danger!, to stderr
```

Example using the `Console` class:

```js
const out = getStreamSomehow();
const err = getStreamSomehow();
const myConsole = new console.Console(out, err);

myConsole.log('hello world');
// Prints: hello world, to out
myConsole.log('hello %s', 'world');
// Prints: hello world, to out
myConsole.error(new Error('Whoops, something bad happened'));
// Prints: [Error: Whoops, something bad happened], to err

const name = 'Will Robinson';
myConsole.warn(`Danger ${name}! Danger!`);
// Prints: Danger Will Robinson! Danger!, to err
```

## Class: `Console`

<!-- YAML
changes:
  - version: v8.0.0
    pr-url: nodejs#9744
    description: Errors that occur while writing to the underlying streams
                 will now be ignored by default.
-->

<!--type=class-->

The `Console` class can be used to create a simple logger with configurable
output streams and can be accessed using either `require('node:console').Console`
or `console.Console` (or their destructured counterparts):

```mjs
import { Console } from 'node:console';
```

```cjs
const { Console } = require('node:console');
```

```js
const { Console } = console;
```

### `new Console(stdout[, stderr][, ignoreErrors])`

### `new Console(options)`

<!-- YAML
changes:
  - version:
     - v14.2.0
     - v12.17.0
    pr-url: nodejs#32964
    description: The `groupIndentation` option was introduced.
  - version: v11.7.0
    pr-url: nodejs#24978
    description: The `inspectOptions` option is introduced.
  - version: v10.0.0
    pr-url: nodejs#19372
    description: The `Console` constructor now supports an `options` argument,
                 and the `colorMode` option was introduced.
  - version: v8.0.0
    pr-url: nodejs#9744
    description: The `ignoreErrors` option was introduced.
-->

* `options` {Object}
  * `stdout` {stream.Writable}
  * `stderr` {stream.Writable}
  * `ignoreErrors` {boolean} Ignore errors when writing to the underlying
    streams. **Default:** `true`.
  * `colorMode` {boolean|string} Set color support for this `Console` instance.
    Setting to `true` enables coloring while inspecting values. Setting to
    `false` disables coloring while inspecting values. Setting to
    `'auto'` makes color support depend on the value of the `isTTY` property
    and the value returned by `getColorDepth()` on the respective stream. This
    option can not be used, if `inspectOptions.colors` is set as well.
    **Default:** `'auto'`.
  * `inspectOptions` {Object} Specifies options that are passed along to
    [`util.inspect()`][].
  * `groupIndentation` {number} Set group indentation.
    **Default:** `2`.

Creates a new `Console` with one or two writable stream instances. `stdout` is a
writable stream to print log or info output. `stderr` is used for warning or
error output. If `stderr` is not provided, `stdout` is used for `stderr`.

```mjs
import { createWriteStream } from 'node:fs';
import { Console } from 'node:console';
// Alternatively
// const { Console } = console;

const output = createWriteStream('./stdout.log');
const errorOutput = createWriteStream('./stderr.log');
// Custom simple logger
const logger = new Console({ stdout: output, stderr: errorOutput });
// use it like console
const count = 5;
logger.log('count: %d', count);
// In stdout.log: count 5
```

```cjs
const fs = require('node:fs');
const { Console } = require('node:console');
// Alternatively
// const { Console } = console;

const output = fs.createWriteStream('./stdout.log');
const errorOutput = fs.createWriteStream('./stderr.log');
// Custom simple logger
const logger = new Console({ stdout: output, stderr: errorOutput });
// use it like console
const count = 5;
logger.log('count: %d', count);
// In stdout.log: count 5
```

The global `console` is a special `Console` whose output is sent to
[`process.stdout`][] and [`process.stderr`][]. It is equivalent to calling:

```js
new Console({ stdout: process.stdout, stderr: process.stderr });
```

### `console.assert(value[, ...message])`

<!-- YAML
added: v0.1.101
changes:
  - version: v10.0.0
    pr-url: nodejs#17706
    description: The implementation is now spec compliant and does not throw
                 anymore.
-->

* `value` {any} The value tested for being truthy.
* `...message` {any} All arguments besides `value` are used as error message.

`console.assert()` writes a message if `value` is [falsy][] or omitted. It only
writes a message and does not otherwise affect execution. The output always
starts with `"Assertion failed"`. If provided, `message` is formatted using
[`util.format()`][].

If `value` is [truthy][], nothing happens.

```js
console.assert(true, 'does nothing');

console.assert(false, 'Whoops %s work', 'didn\'t');
// Assertion failed: Whoops didn't work

console.assert();
// Assertion failed
```

### `console.clear()`

<!-- YAML
added: v8.3.0
-->

When `stdout` is a TTY, calling `console.clear()` will attempt to clear the
TTY. When `stdout` is not a TTY, this method does nothing.

The specific operation of `console.clear()` can vary across operating systems
and terminal types. For most Linux operating systems, `console.clear()`
operates similarly to the `clear` shell command. On Windows, `console.clear()`
will clear only the output in the current terminal viewport for the Node.js
binary.

### `console.count([label])`

<!-- YAML
added: v8.3.0
-->

* `label` {string} The display label for the counter. **Default:** `'default'`.

Maintains an internal counter specific to `label` and outputs to `stdout` the
number of times `console.count()` has been called with the given `label`.

<!-- eslint-skip -->

```js
> console.count()
default: 1
undefined
> console.count('default')
default: 2
undefined
> console.count('abc')
abc: 1
undefined
> console.count('xyz')
xyz: 1
undefined
> console.count('abc')
abc: 2
undefined
> console.count()
default: 3
undefined
>
```

### `console.countReset([label])`

<!-- YAML
added: v8.3.0
-->

* `label` {string} The display label for the counter. **Default:** `'default'`.

Resets the internal counter specific to `label`.

<!-- eslint-skip -->

```js
> console.count('abc');
abc: 1
undefined
> console.countReset('abc');
undefined
> console.count('abc');
abc: 1
undefined
>
```

### `console.debug(data[, ...args])`

<!-- YAML
added: v8.0.0
changes:
  - version: v8.10.0
    pr-url: nodejs#17033
    description: "`console.debug` is now an alias for `console.log`."
-->

* `data` {any}
* `...args` {any}

The `console.debug()` function is an alias for [`console.log()`][].

### `console.dir(obj[, options])`

<!-- YAML
added: v0.1.101
-->

* `obj` {any}
* `options` {Object}
  * `showHidden` {boolean} If `true` then the object's non-enumerable and symbol
    properties will be shown too. **Default:** `false`.
  * `depth` {number} Tells [`util.inspect()`][] how many times to recurse while
    formatting the object. This is useful for inspecting large complicated
    objects. To make it recurse indefinitely, pass `null`. **Default:** `2`.
  * `colors` {boolean} If `true`, then the output will be styled with ANSI color
    codes. Colors are customizable;
    see [customizing `util.inspect()` colors][]. **Default:** `false`.

Uses [`util.inspect()`][] on `obj` and prints the resulting string to `stdout`.
This function bypasses any custom `inspect()` function defined on `obj`.

### `console.dirxml(...data)`

<!-- YAML
added: v8.0.0
changes:
  - version: v9.3.0
    pr-url: nodejs#17152
    description: "`console.dirxml` now calls `console.log` for its arguments."
-->

* `...data` {any}

This method calls `console.log()` passing it the arguments received.
This method does not produce any XML formatting.

### `console.error([data][, ...args])`

<!-- YAML
added: v0.1.100
-->

* `data` {any}
* `...args` {any}

Prints to `stderr` with newline. Multiple arguments can be passed, with the
first used as the primary message and all additional used as substitution
values similar to printf(3) (the arguments are all passed to
[`util.format()`][]).

```js
const code = 5;
console.error('error #%d', code);
// Prints: error nodejs#5, to stderr
console.error('error', code);
// Prints: error 5, to stderr
```

If formatting elements (e.g. `%d`) are not found in the first string then
[`util.inspect()`][] is called on each argument and the resulting string
values are concatenated. See [`util.format()`][] for more information.

### `console.group([...label])`

<!-- YAML
added: v8.5.0
-->

* `...label` {any}

Increases indentation of subsequent lines by spaces for `groupIndentation`
length.

If one or more `label`s are provided, those are printed first without the
additional indentation.

### `console.groupCollapsed()`

<!-- YAML
  added: v8.5.0
-->

An alias for [`console.group()`][].

### `console.groupEnd()`

<!-- YAML
added: v8.5.0
-->

Decreases indentation of subsequent lines by spaces for `groupIndentation`
length.

### `console.info([data][, ...args])`

<!-- YAML
added: v0.1.100
-->

* `data` {any}
* `...args` {any}

The `console.info()` function is an alias for [`console.log()`][].

### `console.log([data][, ...args])`

<!-- YAML
added: v0.1.100
-->

* `data` {any}
* `...args` {any}

Prints to `stdout` with newline. Multiple arguments can be passed, with the
first used as the primary message and all additional used as substitution
values similar to printf(3) (the arguments are all passed to
[`util.format()`][]).

```js
const count = 5;
console.log('count: %d', count);
// Prints: count: 5, to stdout
console.log('count:', count);
// Prints: count: 5, to stdout
```

See [`util.format()`][] for more information.

### `console.table(tabularData[, properties])`

<!-- YAML
added: v10.0.0
-->

* `tabularData` {any}
* `properties` {string\[]} Alternate properties for constructing the table.

Try to construct a table with the columns of the properties of `tabularData`
(or use `properties`) and rows of `tabularData` and log it. Falls back to just
logging the argument if it can't be parsed as tabular.

```js
// These can't be parsed as tabular data
console.table(Symbol());
// Symbol()

console.table(undefined);
// undefined

console.table([{ a: 1, b: 'Y' }, { a: 'Z', b: 2 }]);
// ┌─────────┬─────┬─────┐
// │ (index) │ a   │ b   │
// ├─────────┼─────┼─────┤
// │ 0       │ 1   │ 'Y' │
// │ 1       │ 'Z' │ 2   │
// └─────────┴─────┴─────┘

console.table([{ a: 1, b: 'Y' }, { a: 'Z', b: 2 }], ['a']);
// ┌─────────┬─────┐
// │ (index) │ a   │
// ├─────────┼─────┤
// │ 0       │ 1   │
// │ 1       │ 'Z' │
// └─────────┴─────┘
```

### `console.time([label])`

<!-- YAML
added: v0.1.104
-->

* `label` {string} **Default:** `'default'`

Starts a timer that can be used to compute the duration of an operation. Timers
are identified by a unique `label`. Use the same `label` when calling
[`console.timeEnd()`][] to stop the timer and output the elapsed time in
suitable time units to `stdout`. For example, if the elapsed
time is 3869ms, `console.timeEnd()` displays "3.869s".

### `console.timeEnd([label])`

<!-- YAML
added: v0.1.104
changes:
  - version: v13.0.0
    pr-url: nodejs#29251
    description: The elapsed time is displayed with a suitable time unit.
  - version: v6.0.0
    pr-url: nodejs#5901
    description: This method no longer supports multiple calls that don't map
                 to individual `console.time()` calls; see below for details.
-->

* `label` {string} **Default:** `'default'`

Stops a timer that was previously started by calling [`console.time()`][] and
prints the result to `stdout`:

```js
console.time('bunch-of-stuff');
// Do a bunch of stuff.
console.timeEnd('bunch-of-stuff');
// Prints: bunch-of-stuff: 225.438ms
```

### `console.timeLog([label][, ...data])`

<!-- YAML
added: v10.7.0
-->

* `label` {string} **Default:** `'default'`
* `...data` {any}

For a timer that was previously started by calling [`console.time()`][], prints
the elapsed time and other `data` arguments to `stdout`:

```js
console.time('process');
const value = expensiveProcess1(); // Returns 42
console.timeLog('process', value);
// Prints "process: 365.227ms 42".
doExpensiveProcess2(value);
console.timeEnd('process');
```

### `console.trace([message][, ...args])`

<!-- YAML
added: v0.1.104
-->

* `message` {any}
* `...args` {any}

Prints to `stderr` the string `'Trace: '`, followed by the [`util.format()`][]
formatted message and stack trace to the current position in the code.

```js
console.trace('Show me');
// Prints: (stack trace will vary based on where trace is called)
//  Trace: Show me
//    at repl:2:9
//    at REPLServer.defaultEval (repl.js:248:27)
//    at bound (domain.js:287:14)
//    at REPLServer.runBound [as eval] (domain.js:300:12)
//    at REPLServer.<anonymous> (repl.js:412:12)
//    at emitOne (events.js:82:20)
//    at REPLServer.emit (events.js:169:7)
//    at REPLServer.Interface._onLine (readline.js:210:10)
//    at REPLServer.Interface._line (readline.js:549:8)
//    at REPLServer.Interface._ttyWrite (readline.js:826:14)
```

### `console.warn([data][, ...args])`

<!-- YAML
added: v0.1.100
-->

* `data` {any}
* `...args` {any}

The `console.warn()` function is an alias for [`console.error()`][].

## Inspector only methods

The following methods are exposed by the V8 engine in the general API but do
not display anything unless used in conjunction with the [inspector][]
(`--inspect` flag).

### `console.profile([label])`

<!-- YAML
added: v8.0.0
-->

* `label` {string}

This method does not display anything unless used in the inspector. The
`console.profile()` method starts a JavaScript CPU profile with an optional
label until [`console.profileEnd()`][] is called. The profile is then added to
the **Profile** panel of the inspector.

```js
console.profile('MyLabel');
// Some code
console.profileEnd('MyLabel');
// Adds the profile 'MyLabel' to the Profiles panel of the inspector.
```

### `console.profileEnd([label])`

<!-- YAML
added: v8.0.0
-->

* `label` {string}

This method does not display anything unless used in the inspector. Stops the
current JavaScript CPU profiling session if one has been started and prints
the report to the **Profiles** panel of the inspector. See
[`console.profile()`][] for an example.

If this method is called without a label, the most recently started profile is
stopped.

### `console.timeStamp([label])`

<!-- YAML
added: v8.0.0
-->

* `label` {string}

This method does not display anything unless used in the inspector. The
`console.timeStamp()` method adds an event with the label `'label'` to the
**Timeline** panel of the inspector.

[`console.error()`]: #consoleerrordata-args
[`console.group()`]: #consolegrouplabel
[`console.log()`]: #consolelogdata-args
[`console.profile()`]: #consoleprofilelabel
[`console.profileEnd()`]: #consoleprofileendlabel
[`console.time()`]: #consoletimelabel
[`console.timeEnd()`]: #consoletimeendlabel
[`process.stderr`]: process.md#processstderr
[`process.stdout`]: process.md#processstdout
[`util.format()`]: util.md#utilformatformat-args
[`util.inspect()`]: util.md#utilinspectobject-options
[customizing `util.inspect()` colors]: util.md#customizing-utilinspect-colors
[falsy]: https://developer.mozilla.org/en-US/docs/Glossary/Falsy
[inspector]: debugger.md
[note on process I/O]: process.md#a-note-on-process-io
[truthy]: https://developer.mozilla.org/en-US/docs/Glossary/Truthy
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