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Add Support For Showing a Custom Type View via TypeCustomDebugDataView or Annotations

Open psxvoid opened this issue 2 years ago • 3 comments

Hi,

It seems currently vscode-java-debug doesn't support a way to have different representations of a type during debug in inline view, "variables" and "watch" windows.

Environment
  • Operating System: Windows 10 19043.1645 (x64)
  • JDK version: Java 11 (Oracle JDK 16)
  • Visual Studio Code version: 1.66.2
  • Java extension version: 1.6.0
  • Java Debugger extension version: 0.40.1
Steps To Reproduce
  1. Start a debugging session in vscode for any java file.
  2. See how class variables are represented in inline-view, "variables" and "watch" windows.
Current Result

For example, here is how it looks like during debug - inline view (extension version v0.40.1): current-inline-view

and here is overridden toString method in the Point class: point-ovirridden

notice, I have the following options in .vscode/settings.json:

{
  "java.debug.settings.showQualifiedNames": false,
  "java.debug.settings.showToString": true,
  "java.debug.settings.showLogicalStructure": true
}

also, when I expand an array in the variable view, the nested types are not showing until I click(...): array-list-expanded-view

It seems there are no ways to enable a custom data view for a particular types, right?

Expected Result

It would be cool to have something like that: inline-view-expected

It seems like it can be done using either:

  1. Adding an option to enable displaying a result of overridden toString method, e.g. java.debug.settings.showToStringInlineView: true
  2. Add "Java Type Renderer" to support custom data views similar to IntellijIdea "debugger -> Customize Data Views -> Java Type Renderer" (see link #1 in Additional Informations)
  3. Add something like DebuggerDisplay annotation similar to C# DebuggerDisplayAttribute (see link #2 in Additional Informatins)

For me the second way seems more appealing because it may allow setting custom debug views even for Java internal classes like java.utils.ArrayList

Additional Informations

For example, here are some StackOverflow questions that illustrate the problem:

  1. IntelliJ change toString for debug mode (variables view) | StackOverflow
  2. Display custom string in debugger variables | StackOverflow

psxvoid avatar May 10 '22 04:05 psxvoid

The latest VS Code 1.67 version introduces a new setting debug.autoExpandLazyVariables to allow you to expand the variable toString value by default. Could you have a try to see if it meets your requirement?

testforstephen avatar May 10 '22 05:05 testforstephen

Thanks! It works, and it's definitely better than nothing.

However, having a custom debug view for variables in the inline view is still can provide a lot of value (separately from expanding toString).

psxvoid avatar May 10 '22 05:05 psxvoid

I think the answer is no, but is there a way to write a custom visualizer extension similar to how Visual Studio supports?

terryaney avatar Mar 08 '23 03:03 terryaney