Diagnostics show empty parentheses if no code specified for error (regression)

[StephenWeatherford]

Issue Type: Bug

Pretty sure this did not happen in 1.36.

1. Install this extension: msazurermtools.azurerm-vscode-tools
2. Open a .json file with these contents:

{
    "$schema": "http://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "location": {
            "type": "string"
        }
    }
}

3. Check issues window
   
   Expected: The second error should not show the parentheses around an empty diagnostic code "()".
   (NOTE: The first error comes from the built-in JSON language server, the second comes from the extension)

The code that's setting the error code is here:
https://github.com/microsoft/vscode-azurearmtools/blob/e4a1b209563e4396b5ca081c6c1931d75c09d599/src/AzureRMTools.ts#L356

NOTE: Previously, if you left diagnostic.code blank, vscode would show "(0)" for the error code. Setting it to empty string seemed to be the only way to keep it from showing. But with 1.37, I've tried 0, "", undefined, null, nothing seems to allow me an empty error code without the confusing "()" showing up.

VS Code version: Code 1.37.0 (036a6b1, 2019-08-08T02:33:50.993Z)
OS version: Windows_NT x64 10.0.18362

System Info

Item	Value
CPUs	Intel(R) Xeon(R) W-2133 CPU @ 3.60GHz (12 x 3600)
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: disabled_off protected_video_decode: unavailable_off rasterization: enabled skia_deferred_display_list: disabled_off skia_renderer: disabled_off surface_synchronization: enabled_on video_decode: enabled viz_display_compositor: disabled_off webgl: enabled webgl2: enabled
Load (avg)	undefined
Memory (System)	31.73GB (17.78GB free)
Process Argv
Screen Reader	no
VM	0%

Extensions (28)

Extension	Author (truncated)	Version
vscode-sqlite	ale	0.8.0
vscode-browser-preview	auc	0.5.9
azure-arm-template-helper	ed-	0.0.17
tslint	eg2	1.0.44
rest-client	hum	0.22.0
vscode-antlr4	mik	2.1.1
azure-pipelines	ms-	1.155.0
vscode-apimanagement	ms-	0.1.1
vscode-azureappservice	ms-	0.15.0
vscode-azurefunctions	ms-	0.17.1
vscode-azurestorage	ms-	0.7.1
vscode-cosmosdb	ms-	0.10.2
vscode-docker	ms-	0.7.0
extension-manifest-editor	ms-	0.1.5
mssql	ms-	1.6.0
python	ms-	2019.8.29288
azure-account	ms-	0.8.4
azurecli	ms-	0.4.6
csharp	ms-	1.21.0
powershell	ms-	2019.5.0
vscode-node-azure-pack	ms-	0.0.9
vscode-typescript-tslint-plugin	ms-	1.2.2
azurerm-vscode-tools	msa	0.6.0
arm-snippets	sam	1.4.17
scope-info	sie	0.2.0
tmcolor	sle	0.0.1
html-preview-vscode	tht	0.2.5
arm-params-generator	wil	0.7.0

[sandy081]

To verify, create an extension that generate an error without code and make sure empty parenthesis are not shown

const diagnosticsCollection = vscode.languages.createDiagnosticCollection('test');
    vscode.window.onDidChangeActiveTextEditor(e => {
        if (e && e.document) {
            const diagnostics: vscode.Diagnostic[] = [];
            const diagnostic = new vscode.Diagnostic(new vscode.Range(new vscode.Position(10, 1), new vscode.Position(10, 10)), 'some error', vscode.DiagnosticSeverity.Error);
            diagnostic.source = 'test';
            diagnostics.push(diagnostic);
            diagnosticsCollection.set(e.document.uri, diagnostics);
        }
    });

[StephenWeatherford]

Thanks!

if (marker.code) {
...

Just want to verify that your intention is to not show anything if the code is set to zero instead of undefined/empty (not sure what the expected is for that).

[sandy081]

Good point, but since code is string value 0 is not ignored. It is ignored only when code is empty or null or undefined.