Can't set breakpoints in perl modules located in subdirectories of workspace

[J0EK3R]

Hi @richterger, dear Gerald,
many thanks for your great work!

Currently I'm running VSCode with Win11 and Perl in WSL und a proper und current installation of your VSCode extension and your LanguageServer.

In my very simply example I'm setting a first breakpoint in start.pl wich works and stops the debugger as expected.
Then I would like to set a second breakpoint within the function "something" in the module "test.pm" wich is located in the subdirectory "Modules" in the workspace.

When I start debugging the first breakpoint works as expected and the debugger stops.
The second breakpoint-Dot in VSCode is getting gray und the debugger didn't stop.

Here is my example:

Workspace: ~/projects/test/
containing file start.pl
and the subdirectory Modules/
containing test.pm

content of ~/projects/test/start.pl

#!/usr/bin/perl

package main;

use strict;
use warnings;

use lib '.';

# include file test.pm in subdirectoty "Modules"
use Modules::test;

# first working breakpoint in the following line
print "something\n";

# call function "something" in Modules/test.pm
Modules::test->something();

content of ~/projects/test/Modules/test.pm

package Modules::test;

use strict;
use warnings;

sub something 
{
    # I want to set the Breakpoint in the following line
    print "something\n";
}

return 1;

content of ~/projects/test/.vscode/settings.json

{
    "perl.enable": true,
    "perl.perlInc": [
        "~/projects/test/",
        "~/projects/test/Modules/",
    ],
    "perl.useTaintForSyntaxCheck": false,
    "perl.logLevel": 2,
    "perl.disableCache": false,
}

content of ~/projects/test/.vscode/launch.json

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "type": "perl",
            "request": "launch",
            "name": "Perl-Debug",
            "program": "${workspaceFolder}/start.pl",
            "stopOnEntry": true,
            "reloadModules": true
        }
    ]
}

Here is some logging from the Perl Language Server:

The first working breakpoint in start.pl

DA: ---> Request: {
   "command" : "breakpointLocations",
   "type" : "request",
   "seq" : 3,
   "arguments" : {
      "line" : 14,
      "source" : {
         "path" : "/home/jochen/projects/test/start.pl",
         "name" : "start.pl"
      }
   }
}

DAI: <--- To debuggee: {
   "jsonrpc" : "2.0",
   "filename" : "/home/jochen/projects/test/start.pl",
   "command" : "can_break",
   "seq" : 1000000000,
   "end_line" : null,
   "line" : 14
}

DAI: ---> From debuggee: {
   "command" : "di_response",
   "seq" : 1000000000,
   "arguments" : {
      "breakpoints" : [
         {
            "line" : 14
         }
      ]
   },
   "type" : "dbgint"
}

DA: <--- Response: {
   "command" : "breakpointLocations",
   "request_seq" : 3,
   "type" : "response",
   "body" : {
      "breakpoints" : [
         {
            "line" : 14
         }
      ]
   },
   "seq" : 3,
   "success" : true
}

DA: ---> Request: {
   "command" : "setBreakpoints",
   "arguments" : {
      "lines" : [
         14
      ],
      "source" : {
         "path" : "/home/jochen/projects/test/start.pl",
         "name" : "start.pl"
      },
      "breakpoints" : [
         {
            "line" : 14
         }
      ],
      "sourceModified" : false
   },
   "seq" : 5,
   "type" : "request"
}

DA: <--- Response: {
   "body" : {
      "breakpoints" : [
         {
            "verified" : true,
            "line" : 14,
            "message" : null,
            "id" : 0,
            "source" : {
               "path" : "/home/jochen/projects/test/start.pl"
            }
         }
      ]
   },
   "type" : "response",
   "seq" : 5,
   "success" : true,
   "command" : "setBreakpoints",
   "request_seq" : 5
}

The second non-working breakpoint in Modules/test.pm

DA: ---> Request: {
   "command" : "setBreakpoints",
   "arguments" : {
      "breakpoints" : [
         {
            "line" : 9
         }
      ],
      "sourceModified" : false,
      "lines" : [
         9
      ],
      "source" : {
         "path" : "/home/jochen/projects/test/Modules/test.pm",
         "name" : "test.pm"
      }
   },
   "seq" : 6,
   "type" : "request"
}

DAI: <--- To debuggee: {
   "breakpoints" : [
      [
         9,
         null
      ]
   ],
   "seq" : 1000000003,
   "command" : "breakpoint",
   "filename" : "/home/jochen/projects/test/Modules/test.pm",
   "jsonrpc" : "2.0"
}

DAI: ---> From debuggee: {
   "type" : "dbgint",
   "arguments" : {
      "breakpoints" : [
         [
            9,
            null,
            null,
            null,
            null,
            null,
            1
         ]
      ]
   },
   "seq" : 1000000003,
   "command" : "di_response"
}

DA: <--- Response: {
   "command" : "setBreakpoints",
   "request_seq" : 6,
   "success" : true,
   "seq" : 6,
   "type" : "response",
   "body" : {
      "breakpoints" : [
         {
            "message" : null,
            "id" : 1,
            "source" : {
               "path" : null
            },
            "verified" : false,
            "line" : 0
         }
      ]
   }
}

But - after stopping at the first breakpoint in start.pl:
If I step-in (F11) from start.pl into the funtion-call "something", then VSCode opens "Modules/test.pm" in a new readonly page where I'm able to set my desired breakpoint (while debugging) - wich will work.

Noticeable is that the shown path when hovering with the mouse over the pages tab is "Modules/test.pm".
When opening the file by double-clicking from within the workspace-Window of VSCode the full path as mouse-over-info is "~/procests/test/Modules/test.pm".

Here is the logging of successfully setting the breakpoint in test.pm:

DA: ---> Request: {
   "command" : "setBreakpoints",
   "type" : "request",
   "seq" : 32,
   "arguments" : {
      "sourceModified" : false,
      "breakpoints" : [
         {
            "line" : 9
         }
      ],
      "source" : {
         "path" : "Modules/test.pm"
      },
      "lines" : [
         9
      ]
   }
}

DAI: <--- To debuggee: {
   "command" : "breakpoint",
   "filename" : "Modules/test.pm",
   "jsonrpc" : "2.0",
   "breakpoints" : [
      [
         9,
         null
      ]
   ],
   "seq" : 1000000025
}

DAI: ---> From debuggee: {
   "command" : "di_response",
   "arguments" : {
      "breakpoints_set" : 1,
      "breakpoints" : [
         [
            9,
            null,
            1,
            null,
            "9",
            "Modules/test.pm"
         ]
      ]
   },
   "seq" : 1000000025,
   "type" : "dbgint"
}

DA: <--- Response: {
   "seq" : 32,
   "success" : true,
   "type" : "response",
   "body" : {
      "breakpoints" : [
         {
            "message" : null,
            "id" : 0,
            "source" : {
               "path" : "Modules/test.pm"
            },
            "verified" : true,
            "line" : 9
         }
      ]
   },
   "request_seq" : 32,
   "command" : "setBreakpoints"
}

DA: ---> Request: {
   "type" : "request",
   "arguments" : {
      "line" : 9,
      "source" : {
         "path" : "Modules/test.pm"
      }
   },
   "seq" : 33,
   "command" : "breakpointLocations"
}

DAI: <--- To debuggee: {
   "seq" : 1000000026,
   "end_line" : null,
   "line" : 9,
   "jsonrpc" : "2.0",
   "filename" : "Modules/test.pm",
   "command" : "can_break"
}

DAI: ---> From debuggee: {
   "arguments" : {
      "breakpoints" : [
         {
            "line" : 9
         }
      ]
   },
   "seq" : 1000000026,
   "type" : "dbgint",
   "command" : "di_response"
}

DA: <--- Response: {
   "request_seq" : 33,
   "command" : "breakpointLocations",
   "type" : "response",
   "body" : {
      "breakpoints" : [
         {
            "line" : 9
         }
      ]
   },
   "seq" : 33,
   "success" : true
}

Bug or feature - or my fault!? ;)

[J0EK3R]

Setting "cwd" in launch.json and changing "perl.perlInc" to absolute paths in settings.json did not help.
Is it a problem with Win11 and WSL?

[richterger]

I guess the problem is the use lib '.'; . Can you try to replace the dot with an absolute path?

[J0EK3R]

Yes, that solved the "test problem":

#!/usr/bin/perl

package main;

use strict;
use warnings;

# I guess the problem is the use lib '.'; . Can you try to replace the dot with an absolute path?
# use lib '.'; 
use lib '/home/jochen/projects/test';

# include file test.pm in subdirectoty "Modules"
use Modules::test;

# first working breakpoint in the following line
print "something\n";

# call function "something" in Modules/test.pm
Modules::test->something();

Is there a possibility to set the use lib with the absolute path outside my entry main file - perhaps as option like setting the include path "perl.perlInc" in settings.json?

It's my target to debug my perl module for fhem.

Sorry, I'm pretty out of the perl-context at the moment... ;)

[Devirex]

It's my target to debug my perl module for fhem.

Sorry, I'm pretty out of the perl-context at the moment... ;)

Same here, you can set the modpath to the absolute path in your fhem.cfg.
attr global modpath /opt/fhem

Explanation:
Breakpoints are set in vsCode on the absolute path of the file. FHEM loads the files from relative path ('modpath' defaults to '.' ).
if you change the modepath to an absolute path, FHEM start to load them with absolute paths and the breakpoints start to work.

[J0EK3R]

Oh, thank you for the hint!
I'll try it out.

@Devirex did you manage to set breakpoints and debug FHEM in VSCode?

[Devirex]

Oh, thank you for the hint! I'll try it out.

@Devirex did you manage to set breakpoints and debug FHEM in VSCode?

Yes, ensure that you have this in your fhem.cfg as well:
attr global nofork 1

It starts the process as one and don create childs. Then configure a post-debug task that kills the language server to get it working properly.

My setup:
i run a fhem-test container in parallel to my „live“ instance, which is also a container. I connect from my windows PC directly to the docker host (my nas) by ssh publickey authentication. From there i could once pick the running container and now it is visible like a workspace to which i connect like to a vscode dev container.
The image has a modified entry.sh to deactivate the fhem service restart routine, to keep the container running i use:
tail /dev/zero > /dev/null

You have to install the Language server in there and don’t forget to install gcc and g++ as well as the prerequisites from the vscode extension first.

[J0EK3R]

Thank you very much! :)
It's good to know that it's possible.