add argument for custom python path

Author: Jelmerro

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2024-2025 Jelmer van Arnhem
+Copyright (c) 2024-2026 Jelmer van Arnhem
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

tppr

@@ -1,15 +1,16 @@
 #!/usr/bin/env bash
 # name=tppr
-# version=0.1.0
+# version=0.2.0
 # description=Tiny Portable Python Runner for hassle-free venv and dep handling
 # url=https://github.com/Jelmerro/tppr
 # author=Jelmer van Arnhem
 # license=MIT
 
 # parse args
 show_help=0
-arg_as_cmd=0
 show_msg=0
+systempython="python"
+arg_as_cmd=0
 show_install=0
 force_reinstall=0
 show_version=0
@@ -20,6 +21,9 @@ while [ -n "$arg" ];do
         break
     elif [[ "$arg" == "-m" || "$arg" == "--show-msg" ]];then
         show_msg=1
+    elif [[ "$arg" == "-p" || "$arg" == "--python" ]];then
+        shift
+        systempython=$1
     elif [[ "$arg" == "-c" || "$arg" == "--cmd" ]];then
         arg_as_cmd=1
     elif [[ "$arg" == "-i" || "$arg" == "--show-install" ]];then
@@ -28,7 +32,6 @@ while [ -n "$arg" ];do
         force_reinstall=1
     elif [[ "$arg" == "-v" || "$arg" == "--version" ]];then
         show_version=1
-        break
     elif [[ "$arg" == "-"* ]];then
         if [[ "$arg" == "--"* ]];then
             echo "x Invalid arg '$arg', see -h or --help for info"
@@ -40,17 +43,16 @@ while [ -n "$arg" ];do
             elif [[ "$char" == "h" ]];then
                 show_help=1
                 break 2
-            elif [[ "$char" == "c" ]];then
-                arg_as_cmd=1
             elif [[ "$char" == "m" ]];then
                 show_msg=1
+            elif [[ "$char" == "c" ]];then
+                arg_as_cmd=1
             elif [[ "$char" == "i" ]];then
                 show_install=1
             elif [[ "$char" == "r" ]];then
                 force_reinstall=1
             elif [[ "$char" == "v" ]];then
                 show_version=1
-                break 2
             else
                 echo "x Invalid short arg '$char', see -h or --help for info"
                 exit 1
@@ -64,6 +66,21 @@ while [ -n "$arg" ];do
 done
 shift
 
+# get version from python path, command or system python, otherwise exit
+if ! command -v "$systempython" >/dev/null 2>&1;then
+    systempython=$(realpath -q "$systempython")
+    if [ ! -f "$systempython" ];then
+        echo "x Invalid python path '$systempython', file not found"
+        exit 1
+    fi
+fi
+full_version=$("$systempython" -c "import platform;print(platform.python_version())" 2>/dev/null)
+if [ -z "$full_version" ] || [ "$full_version" == "" ];then
+    echo "x Invalid python path '$systempython', not a valid python binary"
+    exit 1
+fi
+version=${full_version%.*}
+
 # echo helper to only show messages if enabled
 msg() {
     if [ "$show_msg" == 1 ];then
@@ -73,7 +90,8 @@ msg() {
 
 # early exit paths
 if [ "$show_version" == 1 ];then
-    echo "This is tppr version 0.1.0"
+    echo "This is tppr version 0.2.0"
+    echo "Python version currently used is $full_version"
     echo "The Tiny Portable Python Runner for hassle-free venv and dep handling"
     echo "Please see https://github.com/Jelmerro/tppr for updates and info"
     exit
@@ -88,17 +106,18 @@ if [ "$show_help" == 1 ];then
     echo "  ...   Any arguments meant for the python script go here"
     echo
     echo "options:"
-    echo "  -h, --help          Show this help message and exit"
-    echo "  -c, --cmd           File arg is passed to Python's -c as cmd instead"
-    echo "  -m, --show-msg      Print tppr info messages while preparing to run"
-    echo "  -i, --show-install  Print pip requirements installation output"
-    echo "  -r, --reinstall     Reinstall regardless of a correctly versioned venv"
-    echo "  -v, --version       Show program version info and exit"
+    echo "  -h, --help           Show this help message and exit"
+    echo "  -c, --cmd            File arg is passed to Python's -c as cmd instead"
+    echo "  -m, --show-msg       Print tppr info messages while preparing to run"
+    echo "  -i, --show-install   Print pip requirements installation output"
+    echo "  -r, --reinstall      Reinstall regardless of a correctly versioned venv"
+    echo "  -p <p>, --python <p> Set the python binary location to <p>"
+    echo "  -v, --version        Show program version info and exit"
     exit
 fi
 if [ -z "$arg" ] || [ "$arg" == "" ];then
     msg "> no file provided, starting interactive system python"
-    python
+    "$systempython"
     exit
 fi
 file=$(realpath "$arg")
@@ -116,17 +135,15 @@ if [[ "$dir" == "/" ]];then
     msg "> project dir not found, running with system python"
     if [ "$arg_as_cmd" == 1 ];then
         msg "> pass argument as cmd instead of filename"
-        python -c "$arg" "$@"
+        "$systempython" -c "$arg" "$@"
     else
-        python "$file" "$@"
+        "$systempython" "$file" "$@"
     fi
     exit
 fi
 msg "> project dir detected as $dir"
 
-# find latest python version and latest executable paths
-full_version=$(python -c "import platform;print(platform.python_version())")
-version=${full_version%.*}
+# minimal required executable paths inside the venv
 python="$dir/venv/bin/python$version"
 pip="$dir/venv/bin/pip$version"
 activate="$dir/venv/bin/activate"
@@ -145,7 +162,7 @@ fi
 # create new venv and install deps, then source it
 if [ ! -f "$python" ] || [ ! -f "$pip" ] || [ ! -f "$activate" ];then
     msg "> creating venv"
-    "python$version" -m venv "$dir/venv"
+    "$systempython" -m venv "$dir/venv"
     source "$activate"
     stdout="/dev/stdout"
     stderr="/dev/stderr"