Unexplained error messages when not all required packages installed

[PokhodenkoSA]

As a developer I have installed numba-dppy: python setup.py develop. It works without errors.
When I start tests python -m unuttest numba_dppy.tests -v I see strange fails:

======================================================================
ERROR: test_arg_with_accessor (numba_dppy.tests.test_arg_accessor.TestDPPYArgAccessorGPU)
----------------------------------------------------------------------
Traceback (most recent call last):
 File "C:\Users\spokhode\dev\numba-dppy\numba_dppy\tests\test_arg_accessor.py", line 58, in test_arg_with_accessor
 A, B, C, sum_with_accessor)
 File "C:\Users\spokhode\dev\numba-dppy\numba_dppy\tests\test_arg_accessor.py", line 23, in call_kernel
 func[global_size, dppy.DEFAULT_LOCAL_SIZE](A, B, C)
 File "C:\Users\spokhode\dev\numba-dppy\numba_dppy\compiler.py", line 511, in __call__
 kernel = self.specialize(*args)
 File "C:\Users\spokhode\dev\numba-dppy\numba_dppy\compiler.py", line 534, in specialize
 self.access_types)
 File "C:\Users\spokhode\dev\numba-dppy\numba_dppy\compiler.py", line 137, in compile_kernel
 ordered_arg_access_types=access_types)
 File "C:\Users\spokhode\dev\numba-dppy\numba_dppy\compiler.py", line 356, in __init__
 self.spirv_bc = spirv_generator.llvm_to_spirv(self.context, self.binary)
 File "C:\Users\spokhode\dev\numba-dppy\numba_dppy\spirv_generator.py", line 174, in llvm_to_spirv
 return mod.finalize()
 File "C:\Users\spokhode\dev\numba-dppy\numba_dppy\spirv_generator.py", line 126, in finalize
 self._cmd.generate(ipath=self._llvmfile, opath=spirv_path)
 File "C:\Users\spokhode\dev\numba-dppy\numba_dppy\spirv_generator.py", line 63, in generate
 check_call(["opt","-O1","-o",ipath+'.bc',ipath])
 File "C:\Users\spokhode\dev\numba-dppy\numba_dppy\spirv_generator.py", line 24, in check_call
 return _real_check_call(*args, **kwargs)
 File "c:\Miniconda3\envs\spokhode-numba-dppy-dev\lib\subprocess.py", line 358, in check_call
 retcode = call(*popenargs, **kwargs)
 File "c:\Miniconda3\envs\spokhode-numba-dppy-dev\lib\subprocess.py", line 339, in call
 with Popen(*popenargs, **kwargs) as p:
 File "c:\Miniconda3\envs\spokhode-numba-dppy-dev\lib\subprocess.py", line 800, in __init__
 restore_signals, start_new_session)
 File "c:\Miniconda3\envs\spokhode-numba-dppy-dev\lib\subprocess.py", line 1207, in _execute_child
 startupinfo)
FileNotFoundError: [WinError 2] The system cannot find the file specified

As an experienced user I know that it is because not all packages are installed. Then I go to see README with list of packages I need to install: llvm-spirv, llvmdev, spirv-tools.

But I do not know how new developers will understand the root cause of the problem.

[diptorupd]

The development environment setup for numba-dpex has improved significantly since this issue was opened. We now offer better README and getting started guides, environment.yml files, docker and improved build system setup.
Moreover all requirements are now fulfill-able via wheels and conda packages.

Specific to the posted error back trace, the issue can still occur but user will be prompted that dpcpp-llvm-spirv package is missing.