newterm.sh - easily spawn new gnome-terminals

newterm.sh

#!/bin/bash
set -euo pipefail
shopt -s inherit_errexit

detectshell() {
  SCRIPT=$(cat <<'EOF'
import os
from shellingham import detect_shell, ShellDetectionFailure

def get_shell():
    try:
        name, path = detect_shell(os.getpid())
    except (RuntimeError, ShellDetectionFailure):
        shell = None

        if os.name == "posix":
            shell = os.environ.get("SHELL")
        elif os.name == "nt":
            shell = os.environ.get("COMSPEC")

        if not shell:
            raise RuntimeError("Unable to detect the current shell.")

        name, path = Path(shell).stem, shell

    return name, path

# name and path are usually the same
name, path = get_shell()
print(path)
EOF
)
  python -c "$SCRIPT"
  return "$?"
}

spawnshell () {
  SCRIPT=$(cat <<'EOF'
# Based off https://github.com/python-poetry/poetry/blob/d2485b8f849f0bbfd8f6933b625ea07f11f80615/poetry/utils/shell.py#L37
import os
import sys
from clikit.utils.terminal import Terminal
import pexpect

cmd = sys.argv[1]
shell = sys.argv[2]
no_pyenv = bool(int(sys.argv[3]))

if no_pyenv:
    for v in os.environ.keys():
        if v.startswith("PYENV_"):
            del os.environ[v]

terminal = Terminal()
c = pexpect.spawn(
    shell, ["-i"], dimensions=(terminal.height, terminal.width)
)

if shell == "zsh":
    c.setecho(False)

c.sendline(cmd)

c.interact(escape_character=None)
c.close()

sys.exit(c.exitstatus)
EOF
)
  python -c "$SCRIPT" "$1" "$SHELL" "$DELETE_PYENV_VARIABLES"
  return "$?"
}
export -f spawnshell

tab () {
  gnome-terminal --tab "--working-directory=$1" -- /bin/bash -c 'spawnshell "$1"' -- "$2" #/bin/bash -c 'spawnshellee "$1"' -- "$1"
}

# The preferred shell. Replace 'SHELL=shell' with 'SHELL=$(detectshell)' to detect the 
#  running shell instead. Must support "-i" argument.
SHELL=$(detectshell)
# Should all PYENV_* variables be deleted by python before spawning the shell.
# The PYENV_* environment variables are set by pyenv when a pyenv python executable 
#  is invoked. These variables are then propagated down to the spawned shell. 
# I use this because my prompt changes if the pyenv version is being overridden by the
#  PYENV_VERSION environment variable.
# No reason to disable if you don't use pyenv, it will simply be a no-op if there are
#  no matching environment variables. 
# 0 = disable, 1 = enable
DELETE_PYENV_VARIABLES=1

export SHELL
export DELETE_PYENV_VARIABLES

if [ $# -le 1 ]; then
  echo newterm.sh - Easily spawn new \`gnome-terminal\`s >&2
  echo "Usage: $0 <working dir> <cmd>" >&2
  echo "with arguments repeated as many times as necessary" >&2
  echo 'Example: newterm.sh . "echo hi" /some/path "echo foo"' >&2
  echo 'Shell is configurable by editing the script.'
  exit 1
fi 

while [[ $# -ge 2 ]]; do
  tab "$1" "$2"
  shift
  shift
done