Request type "undefined" is not supported

[sallyur]

Environment

• Operating System: Windows and Mac
• JDK version: JDK 8
• Visual Studio Code version: 1.26.1
• Java extension version: 0.29.0
• Java Debugger extension version: 0.11.0
• Build: 297

Steps To Reproduce

1. Open file Main.java in folder 21.single-file
2. Press ctrl+F5 to start without debugging

Result

Error: Request type "undefined" is not supported. Only "launch" and "attach" are supported.

[Eskibear]

Just took an investigation, the issue must have been there for a long time. The test plan doesn't cover "Start without debugging" , so it has never been discovered.

Background

/**
* Resolves a [debug configuration](#DebugConfiguration) by filling in missing values or by adding/changing/removing attributes.
* If more than one debug configuration provider is registered for the same type, the resolveDebugConfiguration calls are chained
* in arbitrary order and the initial debug configuration is piped through the chain.
* Returning the value 'undefined' prevents the debug session from starting.
*
* @param folder The workspace folder from which the configuration originates from or undefined for a folderless setup.
* @param debugConfiguration The [debug configuration](#DebugConfiguration) to resolve.
* @param token A cancellation token.
* @return The resolved debug configuration or undefined.
*/
resolveDebugConfiguration?(folder: WorkspaceFolder | undefined, debugConfiguration: DebugConfiguration, token?: CancellationToken): ProviderResult<DebugConfiguration>;

When there's no existing launch configuration, "start with/without debugging" calls above API resolveDebugConfiguration with different debugConfiguration .

• F5 : debugConfiguration = { }
• Ctrl+F5 : debugConfiguration = { noDebug: true }

Root cause

Take a look at the following piece of code, it judges the case using Object.keys(config).length === 0. Obviously it doesn't work for the Ctrl+F5 case.
https://github.com/Microsoft/vscode-java-debug/blob/ae23fcb02e252b3ff2b5e2fab8023ea89c812e71/src/configurationProvider.ts#L100-L112

Possible fix

For any DebugConfiguration, request is required (the value should be either "launch" or "attach" for the moment). In case there are new candidates for the request field in the future, I suggest to simply change the conditional Object.keys(config).length === 0 to !config.request .

[Eskibear]

fixed. Could you verify build 299?

[sallyur]

Test passed.

Vscode version: 1.26.1
Build: 299

Now the behavior is:

1. Pressing Ctrl+F5 for a single file it start without debugging
2. Pressing Ctrl+F5 for a first-time-opened project, it will generate a launch.json file. Pressing Ctrl+F5 again it start without debugging