Project setup script

Question

It's a pretty simple script really. I just want to know if there is a way to improve it.

#!/bin/env sh

set -o nounset
set -o errexit

if [[ "$#" -ne 3 ]] && [[ "$#" -ne 2 ]];
then
    echo "Usage: ./project.sh [NAME] [GENERATOR] [MAKEFILES]"
    exit 1
fi


mkdir $HOME/Dev/$1
mkdir $HOME/Dev/$1/src/
mkdir $HOME/Dev/$1/build/
cp $HOME/ProjectSetup/CMakeLists.txt $HOME/Dev/$1/

sed -i "s/set(CMAKE_PROJECT_NAME placeholder/set(CMAKE_PROJECT_NAME $1/" $HOME/Dev/$1/CMakeLists.txt

git init $HOME/Dev/$1/
cat > $HOME/Dev/$1/.gitignore << EOL
build/
compile_commands.json
.vscode/
EOL

touch $HOME/Dev/$1/src/main.cpp
cat > $HOME/Dev/$1/src/main.cpp << EOL 

int main(int argc, const char* argv[])
{
    
    return 0;
}
EOL

if [[ "$#" -eq 3 ]];
then
    cmake -G "$2 - $3" -S $HOME/Dev/$1 -B $HOME/Dev/$1/build/ -DCMAKE_EXPORT_COMPILE_COMMANDS=1
else
    cmake -G "$2" -S $HOME/Dev/$1 -B $HOME/Dev/$1/build/ -DCMAKE_EXPORT_COMPILE_COMMANDS=1
fi
ln -s $HOME/Dev/$1/build/compile_commands.json $HOME/Dev/$1/

Answer 1

Variables

It is a good practice to give meaningful names to the built-in option variables ($1, etc.):

if [[ "$#" -ne 3 ]] && [[ "$#" -ne 2 ]];
then
    echo "Usage: ./project.sh [NAME] [GENERATOR] [MAKEFILES]"
    exit 1
fi

name=$1
generator=$2

When they are used later in the code, you don't have to remember what the option order on the command line was.

DRY

$HOME/Dev/$1 is repeated numerous times in the code. Create a new variable and use that everywhere:

dev_dir=$HOME/Dev/$name

There is no need for 3 mkdir commands if you use the -p option to automatically create parent directories:

mkdir -p $dev_dir/src
mkdir -p $dev_dir/build

You can even do it all with one command using shell wildcard expansion:

mkdir -p $dev_dir/{build,src}

Although, that is arguably less readable than the 2 commands.

Simpler

The touch command should not be necessary since the cat with output redirect will create the main.cpp file if it does not exist.

Style

Usually, the trailing / can be omitted from directory paths, such as:

git init $HOME/Dev/$1/

It is cleaner like:

git init $HOME/Dev/$1