VM: options.columnOffset has no effect on column number in stack trace output

Version: v10.3.0 and v10.15.2
Platform: Linux ip-172-30-3-105 4.14.42-52.37.amzn1.x86_64
Subsystem: vm

In vm.runInNewContext (and maybe other versions of "run", too), the options.columnOffset has no effect. I've tried a couple of intentionally-caused errors with various columnOffset values (ranging from -5 to 5), but the character position reported in the stack trace (via e.stack) is always the same. Note that lineOffset works as expected.

I can't reproduce this in 10.15.3

> vm.runInNewContext('throw new Error();', {}, { columnOffset: 20 })
evalmachine.<anonymous>:1
throw new Error();
^

Error
    at evalmachine.<anonymous>:1:27

@devsnek

@devsnek : Yes, I get the same results with your example, but it appears to only work when the VM code is a single line. I've created a stripped-down version of my code that shows the one change that makes it work or not:

In this example, columnOffset is ignored:

let code = `
throw new Error();
`;
vm.runInNewContext(code, {}, {columnOffset: 20});

// RESULT (truncated):
evalmachine.<anonymous>:2
throw new Error();
^

Error
    at evalmachine.<anonymous>:2:7

But in this example, it works:

let code = `throw new Error();`;
vm.runInNewContext(code, {}, {columnOffset: 20});

// RESULT (truncated):
evalmachine.<anonymous>:1
throw new Error();
^

Error
    at evalmachine.<anonymous>:1:27

Note that the only difference is whether code has an extra newline. In my real code, the source JS is loaded from a file, and typically contains many newlines, but this example (using either a template as show or a simple string with \n characters) shows the difference. That's why it was never working for me (I hadn't tried a simple one-line code test).

PS - The "line" difference between the two examples is expected, and this is easily adjusted using lineOffiset, which works fine in both cases.

The column offset only affects the first line. The reason column offset exists is for script tags in html:

<body>
  <script>maybe code
code
code
code
  </script>
</body>

Every line that isn't the first script tag line has a correct column no matter what, because they start fromt the 1st column. But the source of the js in the first line is offset by 10 (" <script>"), so in order to display the correctly attribute an error to the location of the code within an html document, the offset is used here.

Hmmm. OK. I guess that explains what I'm seeing. If it's only supposed to affect the first line, then maybe this is just a documentation update.

Marking this as a good first issue doc update.

@jasnell

@jasnell Can I do this?

Please feel free!

@jasnell

@jasnell I am adding Note beside columnOffset definition
here https://nodejs.org/api/vm.html#vm_vm_runinnewcontext_code_contextobject_options
Is it correct? Please correct me if I am wrong!!

@jasnell

Hi @jasnell , I don't known if this doc issue update was already made, but, if not, could I give it a shot?

sorry, just saw the notification on this. It appears that this is still up for someone to take on!

doc: clarify that columnOffset applies only to the first line

Navigation Menu

VM: options.columnOffset has no effect on column number in stack trace output #26780

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

VM: options.columnOffset has no effect on column number in stack trace output #26780

Description

Activity

devsnek commented on Mar 19, 2019

Eric24 commented on Mar 19, 2019

devsnek commented on Mar 19, 2019

Eric24 commented on Mar 19, 2019

jasnell commented on Jun 19, 2020

harshilparmar commented on Aug 4, 2020

jasnell commented on Aug 4, 2020

harshilparmar commented on Aug 5, 2020

swallville commented on Dec 3, 2020

jasnell commented on Dec 31, 2020

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

Issue actions