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Get v8 stack traces as an array of CallSite objects.
npm install stack-trace
The stack-trace module makes it easy for you to capture the current stack:
var stackTrace = require('stack-trace'); var trace = stackTrace.get(); require('assert').strictEqual(trace.getFileName(), __filename);
However, sometimes you have already popped the stack you are interested in,
and all you have left is an
Error object. This module can help:
var stackTrace = require('stack-trace'); var err = new Error('something went wrong'); var trace = stackTrace.parse(err); require('assert').strictEqual(trace.getFileName(), __filename);
Please note that parsing the
Error#stack property is not perfect, only
certain properties can be retrieved with it as noted in the API docs below.
stack-trace works great with long-stack-traces, when parsing an
that has crossed the event loop boundary, a
CallSite object returning
getFileName() is created.
All other methods of the event loop boundary call site return
Returns an array of
CallSite objects, where element
0 is the current call
When passing a function on the current stack as the
belowFn parameter, the
returned array will only include
CallSite objects below this function.
err.stack property of an
Error object into an array compatible
with those returned by
stackTrace.get(). However, only the following methods
are implemented on the returned
getFunctionName(), all of the above methods return exactly the
same values as you would get from
is sometimes a little different, but still useful.
The official v8 CallSite object API can be found here. A quick excerpt:
A CallSite object defines the following methods:
- getThis: returns the value of this
- getTypeName: returns the type of this as a string. This is the name of the function stored in the constructor field of this, if available, otherwise the object's [[Class]] internal property.
- getFunction: returns the current function
- getFunctionName: returns the name of the current function, typically its name property. If a name property is not available an attempt will be made to try to infer a name from the function's context.
- getMethodName: returns the name of the property of this or one of its prototypes that holds the current function
- getFileName: if this function was defined in a script returns the name of the script
- getLineNumber: if this function was defined in a script returns the current line number
- getColumnNumber: if this function was defined in a script returns the current column number
- getEvalOrigin: if this function was created using a call to eval returns a CallSite object representing the location where eval was called
- isToplevel: is this a toplevel invocation, that is, is this the global object?
- isEval: does this call take place in code defined by a call to eval?
- isNative: is this call in native V8 code?
- isConstructor: is this a constructor call?
stack-trace is licensed under the MIT license.