maybe I’ll get lucky and someone will help me)

I’m trying to make a flutter build using Jenkins.
Before running, the flutter command apparently calls shared.bat, which is located in flutter/bin.

REM Check that git exists and get the revision
  SET git_exists=false
  2>NUL (
    PUSHD "%flutter_root%"
    FOR /f %%r IN ('git rev-parse HEAD') DO (
      SET git_exists=true
      SET revision=%%r
    )
    POPD
  )
  REM If git didn't execute we don't have git. Exit without /B to avoid retrying.
  if %git_exists% == false echo Error: Unable to find git in your PATH. && EXIT 1

I tried to edit this batch file and the git rev-parse HEAD command runs without errors, I also tried to run this command in papeline jenkins, the result is the same. The problem is that the git_exists variable refuses to be set to true. I’ve already racked my brain why it works this way.

here is my pipeline code:

pipeline {
    agent any
    environment {
        BUILD_DIR = 'E:\WORK\me.develop.projects\grand_train_lite'
    }
    stages {
        stage('build') {
            steps {
                script {
                    echo "build..."
                        
                    bat '''
                    chcp 1251
                    SET git_exists=false
  2>NUL (
    PUSHD "%flutter_root%"
    FOR /f %%r IN ('git rev-parse HEAD') DO (
      SET git_exists=true
       echo 'After2 : %git_exists%'
      SET revision=%%r
    )
    POPD
  )
 echo 'After1 : %git_exists%'
                    flutter doctor
                    '''

                    dir(BUILD_DIR) {
                        if (params.BUILD_TYPE == 'debug') {
                            echo "DEBUG"
                            //pubversion build
                            //bat "echo %PATH%"
                            //bat "pubversion build"
                        }


                    }
                }
            }
        }
    }
}

output:

C:ProgramDataJenkins.jenkinsworkspacegrandtrain lite>chcp 1251 
Текущая кодовая страница: 1251

C:ProgramDataJenkins.jenkinsworkspacegrandtrain lite>SET git_exists=false 

C:ProgramDataJenkins.jenkinsworkspacegrandtrain lite>(
PUSHD "C:UserskompoAppDataLocalflutter"  
 FOR /F %r IN ('git rev-parse HEAD') DO (
SET git_exists=true  
 echo 'After2 : false'  
 SET revision=%r 
)  
 POPD
) 2>NUL 

C:ProgramDataJenkins.jenkinsworkspacegrandtrain lite>echo 'After1 : false' 
'After1 : false'

C:ProgramDataJenkins.jenkinsworkspacegrandtrain lite>flutter doctor 
Error: Unable to find git in your PATH.