Debugger throws exception before hitting first line of code

[HughGrovesArup]

Environment data

• VS Code version: 1.27.0 (user setup)
• Extension version (available under the Extensions sidebar): 2018.8.0
• OS and version: Windows 10
• Python version (& distribution if applicable, e.g. Anaconda): Anaconda 4.2.0 (64-bit) Python 3.6.1
• Type of virtual environment used (N/A | venv | virtualenv | conda | ...): conda
• Relevant/affected Python packages and their versions: n/a

Actual behavior

Debugger does not start. Given file does run as a python file (no exceptions).

Expected behavior

Debugging session starts

Steps to reproduce:

1. Press F5 to start debugging file on network drive

Logs

Output for Python in the Output panel (View→Output, change the drop-down the upper-right of the Output panel to Python)

PS C:\Users\Hugh.Groves> cd '\\global.arup.com\americas\Jobs\STJ\230000\230597-00(ACDO)\4-04 Engineering\4-04-02 Concrete\02 Calculations\19 Staged Construction\99-Tools\CreateBatches'; ${env:PYTHONIOENCODING}='UTF-8'; ${env:PYTHONUNBUFFNIOENCODING}='UTF-8'; ${env:PYTHONUNBUFFERED}='1'; ${env:PYTHONPATH}='c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd'; & 'C:\Users\Hugh.Groves\AppDthon.exe' '-m' 'ptvsd' '--host' 'localhoata\Local\Continuum\Anaconda3\envs\p3\python.exe' '-m' 'ptvsd' '--host' 'localhost' '--port' '53026' '\\global.arup.com\americas\Jobs\STJ\230000\230597-00(ACDO)\4-04 Engineering\4-04-02 Concrete\02 Calculations\19 Staged Construction\99-Tools\CreateBatches\CreateBatches_02.py'
Traceback (most recent call last):
  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\wrapper.py", line 1254, in done
    fut.result()
  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\futures.py", line 40, in result
    reraise(self._exc_info)
  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\reraise3.py", line 8, in reraise
    raise exc_info[1].with_traceback(exc_info[2])
  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\futures.py", line 155, in callback
    x = it.send(fut.result())
  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\wrapper.py", line 1605, in on_stackTrace
    norm_path = self.path_casing.un_normcase(unquote(str(xframe['file'])))  # noqa
  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\pathutils.py", line 30, in un_normcase
    file_path_to_return = self._get_actual_filename(file_path)
  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\pathutils.py", line 60, in _get_actual_filename
    fragments += ["{}[{}]".format(d[:-1], d[-1])]
IndexError: string index out of range
Traceback (most recent call last):
  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\wrapper.py", line 1254, in donetal\ptvsd\ptvsd\wrapper.py", line 1254, in done
    fut.result()                                                                               tal\ptvsd\ptvsd\futures.py", line 40, in result
  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\futures.py", line 40, in result                                                tal\ptvsd\ptvsd\reraise3.py", line 8, in reraise
    reraise(self._exc_info)
  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\futures.py", line 155, in callbacktal\ptvsd\ptvsd\reraise3.py", line 8, in reraise
    raise exc_info[1].with_traceback(exc_info[2])
  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\futures.py", line 155, in callback    x = it.send(fut.result())
  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\wrapper.py", line 1605, in on_stackTrace
    norm_path = self.path_casing.un_normcase(unquote(str(xframe['file'])))  # noqa  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\pathutils.py", line 30, in un_normcase
    file_path_to_return = self._get_actual_filename(file_path)
  File "c:\Users\Hugh.Groves\.vscode\extensions\ms-python.python-2018.8.0\pythonFiles\experimental\ptvsd\ptvsd\pathutils.py", line 60, in _get_actual_filename    fragments += ["{}[{}]".format(d[:-1], d[-1])]
IndexError: string index out of range

Output from Console under the Developer Tools panel (toggle Developer Tools on under Help)

 INFO no standard startup: not the explorer viewlet
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
309C:\Users\Hugh.Groves\AppData\Local\Programs\Microsoft VS Code\resources\app\node_modules.asar\vscode-textmate\release\main.js:2924 [4] - Grammar is in an endless loop - Grammar is not advancing, nor is it pushing/popping
scanNext @ C:\Users\Hugh.Groves\AppData\Local\Programs\Microsoft VS Code\resources\app\node_modules.asar\vscode-textmate\release\main.js:2924
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
446C:\Users\Hugh.Groves\AppData\Local\Programs\Microsoft VS Code\resources\app\node_modules.asar\vscode-textmate\release\main.js:2924 [4] - Grammar is in an endless loop - Grammar is not advancing, nor is it pushing/popping
scanNext @ C:\Users\Hugh.Groves\AppData\Local\Programs\Microsoft VS Code\resources\app\node_modules.asar\vscode-textmate\release\main.js:2924
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)
t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276
/C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1)

[DonJayamanne]

@HughGrovesArup
The issue has been resolved. Please could you test this against our latest development version of the extension. Instructions for installing the dev version of the extension can be found here https://github.com/Microsoft/vscode-python/blob/master/CONTRIBUTING.md#development-build

Please feel free to re-open the issue if the issue persists, or just ping us here and we'll open it.

[HughGrovesArup]

I've tried the new version and get this error dialog box popup:

Nothing abnormal is displayed in the terminal.

The developer console shows this:

INFO no standard startup: not just one text editor /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1) t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 [Extension Host] ApplicationInsights:Sender Array(1) t.log @ /C:/Users/Hugh.Groves/AppData/Local/Programs/Microsoft VS Code/resources/app/out/vs/workbench/workbench.main.js:276 console.ts:136 [Extension Host] ApplicationInsights:Sender [{…}] t.log @ console.ts:136 t._logExtensionHostMessage @ extensionHost.ts:412 (anonymous) @ extensionHost.ts:224 emitTwo @ events.js:126 emit @ events.js:214 emit @ internal/child_process.js:772 _combinedTickCallback @ internal/process/next_tick.js:141 _tickCallback @ internal/process/next_tick.js:180 console.ts:136 [Extension Host] ApplicationInsights:Sender [{…}] t.log @ console.ts:136 t._logExtensionHostMessage @ extensionHost.ts:412 (anonymous) @ extensionHost.ts:224 emitTwo @ events.js:126 emit @ events.js:214 emit @ internal/child_process.js:772 _combinedTickCallback @ internal/process/next_tick.js:141 _tickCallback @ internal/process/next_tick.js:180

[DonJayamanne]

Please could you try debugging a simple process for with a for loop.
Endure the file is in a folder in your local drive, such a C:\temp.

[HughGrovesArup]

Tried a simple for loop in C:/temp, got the same error.

[DonJayamanne]

This is interesting, that's not the error you received in the past. In the past it was an error in the debugger, now you aren't even able to launch the debugger (i.e. it cannot connect to it due to a socket connection issue).
Has something changed since then, e.g. permissions/firewalls, etc.