Parser: Found error node parsing function while using user-defined functions

[Gijsreyn]

Prerequisites

• Write a descriptive title.
• Make sure you are able to repro it on the latest version
• Search the existing issues.

Summary

While writing the reference documentation for #1135, the following example throws an error:

$in = @'
$schema: https://aka.ms/dsc/schemas/v3/bundled/config/document.json
functions:
- namespace: Environment
  members:
    getEnvironmentConfig:
      parameters:
      - name: isProduction
        type: bool
      output:
        type: object
        value: "[if(parameters('isProduction'), 
                   createObject('logLevel', 'error', 'debugMode', false()),
                   createObject('logLevel', 'debug', 'debugMode', true()))]"

resources:
- name: Echo production config
  type: Microsoft.DSC.Debug/Echo
  properties:
    output: "[Environment.getEnvironmentConfig(true())]"
- name: Echo development config
  type: Microsoft.DSC.Debug/Echo
  properties:
    output: "[Environment.getEnvironmentConfig(false())]"
'@
dsc config get --input $in

Steps to reproduce

Run the above code snippet from the description

Expected behavior

results:
- name: Echo production config
  type: Microsoft.DSC.Debug/Echo
  result:
    actualState:
      output:
        logLevel: error
        debugMode: false
- name: Echo development config
  type: Microsoft.DSC.Debug/Echo
  result:
    actualState:
      output:
        logLevel: debug
        debugMode: true
messages: []
hadErrors: false

Actual behavior

2025-09-26T04:52:27.274014Z TRACE dsc_lib::configure: 997: Invoke property expression for output: "[Environment.getEnvironmentConfig(true())]"
2025-09-26T04:52:27.274361Z DEBUG dsc_lib::parser: 48: Parsing statement: [Environment.getEnvironmentConfig(true())]
2025-09-26T04:52:27.274706Z DEBUG dsc_lib::parser: 89: Parsing expression
2025-09-26T04:52:27.275003Z DEBUG dsc_lib::parser::expressions: 43: Parsing function '{Node function (0, 1) - (0, 40)}'
2025-09-26T04:52:27.275529Z ERROR dsc::subcommand: 76: Parser: Found error node parsing function

Error details

Environment data

Name                           Value
----                           -----
PSVersion                      7.5.3
PSEdition                      Core
GitCommitId                    7.5.3
OS                             Microsoft Windows 10.0.26100
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Version

dsc 3.2.0-preview.5

Visuals

No response

[SteveL-MSFT]

The problem seems to be that the grammar doesn't handle true() as it expects true (as a boolean). Will work on a fix.