source_bat.bash is used to retrieve environmental variable changes from batch files when using Git Bash on windows. This is necessary to use Git Bash with batch files like vcvarsall.bat for MSVC and setup.bat for ROS.
To install, copy source_bat.bash to a directory contained in $PATH. Optionally a bash alias can be configured.
alias source_bat="source source_bat.bash"
Example usage in Git Bash to initialize for use with MSVC compilers:
source source_bat.bash c:/Program\ Files\ \(x86\)/Microsoft\ Visual\ Studio/2019/Community/VC/Auxiliary/Build/vcvars64.bat