util.getCallSites

History

util.getCallSites(frameCount?, options?): Object[]

Stability: 1.1Active development

Attributes

frameCount?:integer

Optional number of frames to capture as call site objects. Default: 10. Allowable range is between 1 and 200.

options:Object

Optional

sourceMap:boolean

Reconstruct the original location in the stacktrace from the source-map. Enabled by default with the flag --enable-source-maps.

Returns:Object[]

An array of call site objects

functionName:string

Returns the name of the function associated with this call site.

scriptName:string

Returns the name of the resource that contains the script for the function for this call site.

scriptId:string

Returns the unique id of the script, as in Chrome DevTools protocol Runtime.ScriptId.

lineNumber:number

Returns the JavaScript script line number (1-based).

columnNumber:number

Returns the JavaScript script column number (1-based).

Returns an array of call site objects containing the stack of the caller function.

Unlike accessing an error.stack, the result returned from this API is not interfered with Error.prepareStackTrace.

import { getCallSites } from 'node:util';

function exampleFunction() {
  const callSites = getCallSites();

  console.log('Call Sites:');
  callSites.forEach((callSite, index) => {
    console.log(`CallSite ${index + 1}:`);
    console.log(`Function Name: ${callSite.functionName}`);
    console.log(`Script Name: ${callSite.scriptName}`);
    console.log(`Line Number: ${callSite.lineNumber}`);
    console.log(`Column Number: ${callSite.columnNumber}`);
  });
  // CallSite 1:
  // Function Name: exampleFunction
  // Script Name: /home/example.js
  // Line Number: 5
  // Column Number: 26

  // CallSite 2:
  // Function Name: anotherFunction
  // Script Name: /home/example.js
  // Line Number: 22
  // Column Number: 3

  // ...
}

// A function to simulate another stack layer
function anotherFunction() {
  exampleFunction();
}

anotherFunction();

JavaScript

const { getCallSites } = require('node:util');

function exampleFunction() {
  const callSites = getCallSites();

  console.log('Call Sites:');
  callSites.forEach((callSite, index) => {
    console.log(`CallSite ${index + 1}:`);
    console.log(`Function Name: ${callSite.functionName}`);
    console.log(`Script Name: ${callSite.scriptName}`);
    console.log(`Line Number: ${callSite.lineNumber}`);
    console.log(`Column Number: ${callSite.columnNumber}`);
  });
  // CallSite 1:
  // Function Name: exampleFunction
  // Script Name: /home/example.js
  // Line Number: 5
  // Column Number: 26

  // CallSite 2:
  // Function Name: anotherFunction
  // Script Name: /home/example.js
  // Line Number: 22
  // Column Number: 3

  // ...
}

// A function to simulate another stack layer
function anotherFunction() {
  exampleFunction();
}

anotherFunction();

JavaScript

It is possible to reconstruct the original locations by setting the option sourceMap to true. If the source map is not available, the original location will be the same as the current location. When the --enable-source-maps flag is enabled,sourceMap will be true by default.

import { getCallSites } from 'node:util';

interface Foo {
  foo: string;
}

const callSites = getCallSites({ sourceMap: true });

// With sourceMap:
// Function Name: ''
// Script Name: example.js
// Line Number: 7
// Column Number: 26

// Without sourceMap:
// Function Name: ''
// Script Name: example.js
// Line Number: 2
// Column Number: 26

TypeScript

const { getCallSites } = require('node:util');

const callSites = getCallSites({ sourceMap: true });

// With sourceMap:
// Function Name: ''
// Script Name: example.js
// Line Number: 7
// Column Number: 26

// Without sourceMap:
// Function Name: ''
// Script Name: example.js
// Line Number: 2
// Column Number: 26

JavaScript