Debug console: '\n' not shown as new line for evaluation returning a variablesReference

[yzhang-gh]

Issue Type: Bug

Type these code in the debug console

import numpy as np

np.random.rand(5, 5)

---

VS Code version: Code 1.33.1 (51b0b28, 2019-04-11T08:27:14.102Z)
OS version: Windows_NT x64 10.0.18898

System Info

Item	Value
CPUs	Intel(R) Core(TM) i5-6200U CPU @ 2.30GHz (4 x 2400)
GPU Status	2d_canvas: enabled checker_imaging: disabled_off flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled multiple_raster_threads: enabled_on native_gpu_memory_buffers: disabled_software rasterization: enabled surface_synchronization: enabled_on video_decode: enabled webgl: enabled webgl2: enabled
Memory (System)	7.90GB (3.58GB free)
Process Argv	D:\Workspace\vscode-test
Screen Reader	no
VM	0%

Extensions (20)

Extension	Author (truncated)	Version
spellright	ban	3.0.38
vscode-custom-css	be5	3.0.4
log-wrapper-for-vscode	chr	1.0.2
vsc-material-theme	Equ	2.8.2
vsc-material-theme-icons	equ	0.12.0
vscode-commands	fab	1.2.5
vscode-github-notifications-bell	fab	2.1.5
vscode-highlight	fab	1.3.4
vscode-open-in-application	fab	1.0.5
latex-workshop	Jam	6.5.1
vscode-fix-checksums	leh	1.1.0
rainbow-csv	mec	1.0.0
git-graph	mhu	1.5.0
python	ms-	2019.4.12954
vscode-sort-json	ric	1.13.0
code-settings-sync	Sha	3.2.9
dictionary-completion	yzh	0.8.2
find-word-at-cursor	yzh	0.1.1
markdown-all-in-one	yzh	2.3.1
vscode-jupyter	yzh	1.2.3

[crock]

This is not an issue with VSCode. You have a new line inside a Python list. If you want each item in the list on a new line you need to use a loop and print out each line followed by the new line character.

[yzhang-gh]

I don't get the point. It is a numpy ndarray (not Python list).

>>> import numpy as np
>>> a = np.arange(15).reshape(3, 5)
>>> a
array([[ 0,  1,  2,  3,  4],
       [ 5,  6,  7,  8,  9],
       [10, 11, 12, 13, 14]])

[roblourens]

Possibly an issue for the Python extension?

[vscodebot]

This issue is caused by an extension, please file it with the repository (or contact) the extension has linked in its overview in VS Code or the marketplace for VS Code. See also our issue reporting guidelines.

Happy Coding!

[fabioz]

What seems to be happening is that in the case where an expression is evaluated and returns a variablesReference, the variablesReference is shown the same way it's shown in the variables view (where new lines are changed for a \n representation).

Some more info from the debugger backend:

Given the following Python code (not using numpy to make it simpler):

class Foo(object):

    def __repr__(self):
        return 'aa\nbb\ncc'
    __str__ = __repr__

foo = Foo()
print('add breakpoint here')

Pausing at the breakpoint and sending foo to the repl (by typing foo in the Debug Console) the request sent to the debugger is:

{
    "arguments": {
        "context": "repl",
        "expression": "foo",
        "format": {},
        "frameId": 22
    },
    "command": "evaluate",
    "seq": 1000000016,
    "type": "request"
}

and the response is:

{
    "type": "response", 
    "request_seq": 1000000016, 
    "success": true, 
    "command": "evaluate", 
    "body": {
        "result": "aa\nbb\ncc", 
        "variablesReference": 4, 
        "type": "Foo", 
        "presentationHint": {}
    }, 
    "seq": 42
}

So, you can see that the result has proper new lines and VSCode chose to show it in a single line and not expanded in the debug console (so, there's not much to be done on the extension as it seems to be doing the proper thing).

So, this would be a request (and not a bug since it seems it's deliberately doing the same thing done in the variables view) for VSCode to show new lines expanded in the debug console for a given variablesReference.

As a note, if print(foo) is done, the result is shown expanded -- it'll actually return a variablesReference to None in that case as that's the return of print(foo) but then the representation will be printed as a string afterwards with proper new lines.

[fabioz]

A better title for this issue is probably:

Debug console: '\n' not shown as new line for evaluation returning a variablesReference.

-- note that if variablesReference==0 in the return then the Debug Console properly shows the result expanded.