src/nmutil/toolchain.py

   1 import os
   2 import shutil
   3
   4
   5 __all__ = ["ToolNotFound", "tool_env_var", "has_tool", "require_tool"]
   6
   7
   8 class ToolNotFound(Exception):
   9     pass
  10
  11
  12 def tool_env_var(name):
  13     return name.upper().replace("-", "_").replace("+", "X")
  14
  15
  16 def _get_tool(name):
  17     return os.environ.get(tool_env_var(name), name)
  18
  19
  20 def has_tool(name):
  21     return shutil.which(_get_tool(name)) is not None
  22
  23
  24 def require_tool(name):
  25     env_var = tool_env_var(name)
  26     path = _get_tool(name)
  27     if shutil.which(path) is None:
  28         if env_var in os.environ:
  29             raise ToolNotFound("Could not find required tool {} in {} as "
  30                                "specified via the {} environment variable".
  31                                format(name, path, env_var))
  32         else:
  33             raise ToolNotFound("Could not find required tool {} in PATH. Place "
  34                                "it directly in PATH or specify path explicitly "
  35                                "via the {} environment variable".
  36                                format(name, env_var))
  37     return path