fix: cancel debug launch when ESC is pressed on input variable dialog

[na3shkw]

Fixes #248716

When a user cancels a pickString (or other input variable) dialog by pressing ESC during a debug launch, the launch incorrectly continues with the unresolved ${input:...} string instead of aborting.

Root Cause

resolveWithInteractionReplace was ignoring the return value of resolveWithInteraction, which returns undefined when the user cancels the input. As a result, even after cancellation, parsed.toObject() was called and returned the config with the raw ${input:...} placeholder string, causing the launch to proceed.

Changes

• baseConfigurationResolverService.ts: Check the return value of resolveWithInteraction in resolveWithInteractionReplace. If it returns undefined (user canceled), propagate undefined instead of calling parsed.toObject().
• debugger.ts: Update the return type of substituteVariables to Promise<IConfig | undefined> to reflect that variable resolution can be canceled.
• configurationResolverService.test.ts: Add a test that verifies resolveWithInteractionReplace returns undefined when the user cancels input.

After this fix, pressing ESC on the pickString dialog correctly aborts the launch:

[na3shkw]

@microsoft-github-policy-service agree