install.sh: Python-shebang sed crashes on macOS (BSD sed), unlike the config_template sed a few lines later

[frigusgulo]

Summary

install.sh's Python-shebang normalization step crashes on macOS (BSD sed) because it's missing the OS-specific -i handling that the rest of the script already uses elsewhere.

Where

# Check python
if which python3 > /dev/null 2>&1; then
    sed -i 's/\#\!\/usr\/bin\/env python$/\#\!\/usr\/bin\/env python3/g' ./scripts/*.py
elif which python > /dev/null 2>&1; then
    sed -i 's/\#\!\/usr\/bin\/env python3$/\#\!\/usr\/bin\/env python/g' ./scripts/*.py
else
    printf "${YELLOW}warning:${NC} no python or python3, please install one of them before using py scripts\n"
fi

Note that further down the same script, the config_template sed does branch correctly:

if [ "$SYS" == "Darwin" ]; then
    sed -i '' "/Table directory/s#Default#$work_dir/table/#" $install_dir/config_template
else
    sed -i    "/Table directory/s#Default#$work_dir/table/#" $install_dir/config_template
fi

but the shebang-fixup sed -i a few lines earlier never got the same treatment.

Repro

On macOS:

$ echo '#!/usr/bin/env python' > testshebang.py
$ sed -i 's/\#\!\/usr\/bin\/env python$/\#\!\/usr\/bin\/env python3/g' testshebang.py
sed: 2: "testshebang.py": undefined label 'estshebang.py'
$ echo $?
1
$ cat testshebang.py
#!/usr/bin/env python   # unchanged — sed never ran

BSD sed -i requires an explicit (even empty) backup-suffix argument (sed -i ''); without it, the next argument is consumed as the suffix and the following argument is mis-parsed as the sed command itself.

Observed impact

Ran install.sh on macOS today against current master (b7451a8) — the shebang sed for ./scripts/*.py fails with:

sed: 1: "./scripts/kin2csv.py": invalid command code .

install.sh doesn't check this command's exit status, so installation continues and prints "installation successfully completed" — the failure is silent. In this run the scripts already had #!/usr/bin/env python3 shebangs so nothing was functionally broken, but any script whose shebang genuinely needs normalizing would silently keep the wrong interpreter on macOS.

Suggested fix

Mirror the existing $SYS/$OS-branching pattern already used for the config_template sed a few lines later, e.g.:

if [ "$SYS" == "Darwin" ]; then
    sed -i '' 's/.../.../g' ./scripts/*.py
else
    sed -i    's/.../.../g' ./scripts/*.py
fi

[lvsz2002]

Thank you for reporting this issue and providing a clear reproduction. You are right: the Python shebang normalization currently uses GNU sed syntax and fails with BSD sed on macOS. We will add the Darwin-specific sed -i '' handling.