Copying a long value from debug watch results in pasting partial value

[da2r-20]

• Version: 1.45.0
• Commit: d69a79b
• Date: 2020-05-07T15:57:33.467Z
• Electron: 7.2.4
• Chrome: 78.0.3904.130
• Node.js: 12.8.1
• V8: 7.8.279.23-electron.0
• OS: Darwin x64 18.7.0

For me it reproduced with C++
But it probably occurs in other languages as well, haven't verified that.

Steps to Reproduce:

1. Start a debugging session
2. add an expression that has a long value to watch
   
3. Copy value
4. paste it somewhere in a text area
5. the pasted text appears is limited and ends with '...'
   

Does this issue occur when all extensions are disabled?: Yes

[isidorn]

Please file this against the C++ extension and mention the following:
VS COde sents the clipboard context when copying. Their extension should set the capability supportsClipboardContext and respect the clipboard context by evaluation the full thing.

[WardenGnaw]

@isidorn
In the EvaluateRequest with clipboard as the context, it seems like the expression is set to the value, not the expression. Is this expected?

{"command":"evaluate",
"arguments":{
"expression":"\"abcdefghijklmnopqrstuvwxyz0abcdefghijklmnopqrstuvwxyz1abcdefghijklmnopqrstuvwxyz2abcdefghijklmnopqrstuvwxyz3abcdefghijklmnopqrstuvwxyz4abcdefghijklmnopqrstuvwxyz5abcdefghijklmnopqrstuvwxyz6abcdefghijk\"...","
   frameId":1000,
   "context":"clipboard"
},
"type":"request",
"seq":25}

[isidorn]

@WardenGnaw yeah this is how we implemented it here

vscode/src/vs/workbench/contrib/debug/browser/watchExpressionsView.ts

Line 192 in 0408068

actions.push(this.instantiationService.createInstance(CopyValueAction, CopyValueAction.ID, CopyValueAction.LABEL, expression.value, 'watch'));

Maybe not the best when you do it on a top level wath expression.
We could fix it to make the CopyValue handle both Variable and Expression. But this might be fine for now.

[WardenGnaw]

Hmm. In the C/C++ debugger, it defaults to displaying up to 200 characters. So the value we would get when stopped, would be the truncated 200 limited value.

I was expecting when a user selects Copy Value, an EvaluateRequest would have its expression field set to the original expression (in the image above it would be "str") so we can re-query the debugger to give the full value.

We would do so by noticing it was a ClipboardContext. Tell the debugger to have unlimited display when evaluating a variable, evaluate a variable, reset the display back to the default and return the full display in the response.

[isidorn]

@WardenGnaw you are correct, I have pushed de3e5a4 to tackle this.
Please try it out with vscode insiders from Tuesday and let us know how it works for you.
I have also created this follow up isse for js-debug microsoft/vscode-js-debug#476

[WardenGnaw]

@isidorn Sorry for the delay, I tested this out and the expression of the evaluate request is what we expect, the variable to evaluate.

Thanks you again!

[isidorn]

@WardenGnaw thanks for letting us know!