Variable substitution in launch.json object keys stopped working in 1.99

[zobo]

Does this issue occur when all extensions are disabled?: N/A

Version: 1.99.0 (user setup)
Commit: 4437686
Date: 2025-04-02T21:35:19.530Z
Electron: 34.3.2
ElectronBuildId: 11161073
Chromium: 132.0.6834.210
Node.js: 20.18.3
V8: 13.2.152.41-electron.0
OS: Windows_NT x64 10.0.26100

After upgrading to 1.99 the way variable substitution is performed in launch.json changed. Variables are not resolved anymore in array keys. I'm working with xdebug.php-debug extension.

This is the source launch.json:

    {
      "name": "Listen for Xdebug",
      "type": "php",
      "request": "launch",
      "port": 9003,
      "pathMappings": {
        "${workspaceFolder}": "${workspaceFolder}"
      }
    }

I have verified that this corresponds to what resolveDebugConfiguration sees:

After variable substitution, this is what resolveDebugConfigurationWithSubstitutedVariables and later the debug adapter sees:

    {
      "name": "Listen for Xdebug",
      "type": "php",
      "request": "launch",
      "port": 9003,
      "pathMappings": {
        "${workspaceFolder}": "C:\\workspace_folder\\..."
      }
    }

In previous version, 1.98.2, both the pathMappings object key and value got replaced.

Previous version

Version: 1.98.2 (user setup) Commit: ddc367e Date: 2025-03-12T13:32:45.399Z Electron: 34.2.0 ElectronBuildId: 11161602 Chromium: 132.0.6834.196 Node.js: 20.18.2 V8: 13.2.152.36-electron.0 OS: Windows_NT x64 10.0.26100

Labels: new release, debugger

Ref: xdebug/vscode-php-debug#1004

[zobo]

This has probably something to do with this: c22175d#diff-e482f7894e136562bb05760b6da7f5d40e4721aa06b1432c753cdec530d23850R68-R86

const expr = ConfigurationResolverExpression.parse(config);

The new code does not resolve variables in object keys:

vscode/src/vs/workbench/services/configurationResolver/common/configurationResolverExpression.ts

Line 172 in 0bc678a

this.parseString(obj, key, value);

whereas the old one did:

vscode/src/vs/workbench/services/configurationResolver/common/variableResolver.ts

Lines 147 to 148 in 85be6c3

	const replaced = await this.resolveString(environment, folderUri, key, commandValueMapping, resolvedVariables);
	return [replaced, await this.recursiveResolve(environment, folderUri, value[key], commandValueMapping, resolvedVariables)] as const;

[jusid]

I am also having this issue in 1.99.0.

[OneTone]

Would you please take a look at #245662 as well? @connor4312

[Caffe1neAdd1ct]

Thanks very much for fixing already, great to see a PR already 👍 was starting to look into this regression today.

Would be really great to see the substitution of already selected variables to be shown when selecting the next variable, should be a simple change, but most likely out of scope for this bugfix, will look to raise a PR for this separately.

[samysadi]

This is partially solved in 1.100.
More specifically, while the above substitution in launch.json is running fine, substitutions in tasks using ${input:...} is still failing.

For instance:

"tasks": [ {"label": "My Debug Task", "command": "${input:launchMyDebugConfig}" ],
"inputs": [ { "id": "launchMyDebugConfig", "type": "command", "command": "workbench.action.debug.start", "args": [ "My Debug Config Name" ] } ]

would yield: The terminal process failed to launch: Path to shell executable "${input:launchMyDebugConfig}" does not exist.

This was working in 1.98.

[Caffe1neAdd1ct]

Seems to still have a regression on 1.100/1.99.* compared with 1.98.

Picked variables are no longer substituted in environment variables listed in the launch and potentially other areas, still investigating:

{
        "name": "My Debug Launch",
        "request": "launch",
        
        "env": {
          "THING": "${input:thing}",
        },
        ],
      },


...

    "inputs": [
      {
        "id": "thing",
        "description": "Thing to dynamically drive env variable THING.",
        "type": "pickString",
        "options": [
          {
            "label": "Option1",
            "value": "option-1"
          },
          {
            "label": "Option1",
            "value": "option-2"
          },
          {
            "label": "Option1",
            "value": "option-3"
          }
        ]
      },

(possibly) Caused by the following line change:

public resolveWithEnvironment(environment: IProcessEnvironment, root: IWorkspaceFolder | undefined, value: string): Promise<string> {
		return this.recursiveResolve({ env: this.prepareEnv(environment), userHome: undefined }, root ? root.uri : undefined, value);
	}

src/vs/workbench/services/configurationResolver/common/variableResolver.ts

[connor4312]

Seems to still have a regression on 1.100/1.99.* compared with 1.98.

I do not reproduce

This specific issue (not resolving variables in keys) was fixed a while back. Please open issues with repro's if you find other issues.