Blanks on the left are removed (in the markdown portion) when exporting .py to .ipynb (jupyter)

[dem108]

Environment data

• VS Code version: 1.30.2
• Extension version (available under the Extensions sidebar): 2018.12.1
• OS and version: Windows_NT x64 10.0.17134
• Python version (& distribution if applicable, e.g. Anaconda): 3.6.8
• Type of virtual environment used (N/A | venv | virtualenv | conda | ...): conda
• Relevant/affected Python packages and their versions: none

Expected behaviour

When I export a .py file (which is imported from an .ipynb) to a .ipynb, the new Jupyter notebook should be the same as the original. Especially the markdown portion should not break.

Actual behaviour

Markdown portion breaks because the blanks on the left of each line are removed when exporting .py to .ipynb.

Steps to reproduce:

1. import a notebook from vscode. Import is okay.

{
  "cells": [
    {
      "metadata": {
        "collapsed": true
      },
      "cell_type": "markdown",
      "source": "# Simple Notebook to replicate the issue\n\n## Issue\nWhen export .py with #%% markdown blocks, blanks on the left of each line are removed, breaking the intended markdown format.\n"
    },
    {
      "metadata": {},
      "cell_type": "markdown",
      "source": "## Block of Interest\n\n### Take a look\n\n\n  1. Item 1\n\n    - Item 1-a\n      1. Item 1-a-1\n         - Item 1-a-1-a\n         - Item 1-a-1-b\n      2. Item 1-a-2\n         - Item 1-a-2-a\n         - Item 1-a-2-b\n      3. Item 1-a-3\n         - Item 1-a-3-a\n         - Item 1-a-3-b\n         - Item 1-a-3-c\n\n  2. Item 2"
    }
  ],
  "metadata": {
    "kernelspec": {
      "name": "python36",
      "display_name": "Python 3.6",
      "language": "python"
    },
    "language_info": {
      "mimetype": "text/x-python",
      "nbconvert_exporter": "python",
      "name": "python",
      "pygments_lexer": "ipython3",
      "version": "3.6.6",
      "file_extension": ".py",
      "codemirror_mode": {
        "version": 3,
        "name": "ipython"
      }
    }
  },
  "nbformat": 4,
  "nbformat_minor": 2
}

2. Export the imported .py to .ipynb. The blanks are removed on the left of each line, breaking the intended format.

Logs

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

You can try exporting below Python script for replication.

#%% [markdown]
# # Simple Notebook to replicate the issue
# 
# ## Issue
# When export .py with #%% markdown blocks, blanks on the left of each line are removed, breaking the intended markdown format.
# 
#%% [markdown]
# ## Block of Interest
# 
# ### Take a look
# 
# 
#   1. Item 1
# 
#     - Item 1-a
#       1. Item 1-a-1
#          - Item 1-a-1-a
#          - Item 1-a-1-b
#       2. Item 1-a-2
#          - Item 1-a-2-a
#          - Item 1-a-2-b
#       3. Item 1-a-3
#          - Item 1-a-3-a
#          - Item 1-a-3-b
#          - Item 1-a-3-c
# 
#   2. Item 2

Output from Console under the Developer Tools panel (toggle Developer Tools on under Help; turn on source maps to make any tracebacks be useful by running Enable source map support for extension debugging)

N/A