Line wrapping in console results in duplicate problems

[joelspadin]

Issue Type: Bug

When I run a task in a split terminal such that long warning/error messages wrap to multiple lines, I get two problems for every message that wraps. The first problem only contains the text on the first line, while the second problem contains the entire warning/error message. I specifically see this problem when building a C file with GCC and using the $gcc problem matcher. I do not know if the issue is specific to that problem matcher or if it is an issue with problem matchers in general.

I use waf.io to manage my build, which has many files, but I believe the problem can be reproduced using just GCC and a single C file. I am using GCC version 6.4.0. My tasks.json looks like this:

{
  "tasks": [
    {
      "label": "build",
      "type": "process",
      "command": "python",
      "args": ["waf.py"], // gcc.exe -Wdeprecated-declarations (plus other options not relevant to this issue)
      "group": {
        "kind": "build",
        "isDefault": true
      },
      "problemMatcher": [
        { 
          "base": "$gcc",
          "fileLocation": ["autoDetect", "${workspaceFolder}/build"]
        }
      ]
    }
  ]
}

Then I have a file which generates a long warning message:

// ./compiler.h
#if defined(__GNUC__)
    #define DEPRECATED(func)    __attribute__ ((deprecated)) func
#else
    // implementations for other compilers would go here.
    #define DEPRECATED(func)    func
#endif

// ./some/really/long/path/to/header.h
#include "compiler.h"

// This used to do something, but now it isn't necessary.
static DEPRECATED( __inline int old_function(void) )
{
    return 1;
}

// ./some/really/long/path/to/source.c
#include "header.h"

int main(void)
{
    if (old_function())
    {
        // do something
    }
}

Compiling this results in a warning which looks something like:

..\some\really\long\path\to\source.c:6:8: warning: 'old_function' is deprecated[-Wdeprecated-declarations]
     if (old_function())
         ^~~~~~~~~~~~
In file included from ..\some\really\long\path\to\header.h:2
                      ..\some\really\long\path\to\source.c:2:
C:\projects\example\some\really\long\path\to\header.h:4:51 note: declared here
 static DEPRECATED( __inline void old_function(void) )
                                  ^  
C:\projects\example\compiler.h note: in definition of macro 'DEPRECATED'
 #define DEPRECATED(func)    __attribute__ ((deprecated)) func
                                                          ^~~~

If I am running the build task in a split terminal, that first line tends to get wrapped to something like this:

..\some\really\long\path\to\source.c:5:8: warning: 'old_function' is deprecated[-Wd
eprecated-declarations]

And then in the problems pane I will get two problems:

source.c some\really\long\path\to (2)
    'old_function' is deprecated [-Wd gcc [6, 8]
    'old_function' is deprecated [-Wdeprecated-declarations] gcc [6, 8]

If I run the build task in a terminal that is wide enough that the warning does not get wrapped, then only one problem appears, as I would expect.

VS Code version: Code 1.36.1 (2213894, 2019-07-08T22:59:35.033Z)
OS version: Windows_NT x64 6.1.7601

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz (8 x 3392)
GPU Status	2d_canvas: enabled flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled multiple_raster_threads: enabled_on native_gpu_memory_buffers: disabled_software oop_rasterization: unavailable_off protected_video_decode: unavailable_off rasterization: unavailable_off skia_deferred_display_list: disabled_off skia_renderer: disabled_off surface_synchronization: enabled_on video_decode: unavailable_off viz_display_compositor: disabled_off webgl: enabled webgl2: enabled
Load (avg)	undefined
Memory (System)	31.96GB (13.88GB free)
Process Argv	-n
Screen Reader	no
VM	0%

Extensions

Extension	Author (truncated)	Version
gitignore	cod	0.6.0
arm	dan	0.5.0
xml	Dot	2.5.0
gitlens	eam	9.8.5
tsl-problem-matcher	eam	0.0.4
EditorConfig	Edi	0.13.0
vscode-npm-script	eg2	0.3.8
json-tools	eri	1.0.2
bitbake	Eug	1.1.2
gc-excelviewer	Gra	2.1.32
tabsanity	jed	0.0.11
nearley	kar	1.0.3
rainbow-csv	mec	1.1.1
python	ms-	2019.6.24221
cpptools	ms-	0.24.0
vscode-typescript-tslint-plugin	ms-	1.2.2
autodocstring	njp	0.3.0
rewrap	stk	1.9.1
vscode-icons	vsc	8.8.0
better-align	wwm	1.1.6

[roblourens]

I'm not able to repro this in stable. @alexr00 is there a way that I can verify it with TS or some dummy task?

[roblourens]

In 1.37 I have a task that just echos that data, and uses the same problem matcher, and it looks ok:

[joelspadin]

Are you running Windows 10? I was seeing the issue on Windows 7, so it's possible this only occurs on Windows 7 or when terminal.integrated.windowsEnableConpty is false.

[roblourens]

I was using macOS, but I tried windows, and there I can't even get the problem to show up at all

[alexr00]

Sorry about that, it's a Windows specific issue and it happens regardless of the Windows version. The repro is to make your terminal very narrow then run a task that causes problems.