I am using python package py-solc-x for compiling the smart contract.


Gives path where my test contract exits. 'D:\\new.sol'

Then i use compile_files to compile the contract compile_files([os.path.abspath("D:/new.sol")]) , it gives KeyError.

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Users\Muvi\AppData\Local\Programs\Python\Python36-32\lib\site-packages\solcx\main.py", line 137, in compile_files
    contracts = _parse_compiler_output(stdoutdata)
  File "C:\Users\Muvi\AppData\Local\Programs\Python\Python36-32\lib\site-packages\solcx\main.py", line 73, in _parse_compiler_output
    data['ast'] = sources[source.split(':')[0]]['AST']
KeyError: 'D'

How can i solve this problem?

1 Answer 1


Looks like you've found a bug in py-solc-x.

As far as I can tell, the issue is specific to Windows paths that are given absolutely. I was able to compile successfully by using a path that did not include a drive letter.

I am the maintainer of py-solc-x, I will push a new version with a fix as soon as possible. In the short term try running the script from the same folder as new.sol and compile with solcx.compile_files(['new.sol']).

  • omg.. Thanks a lot sir.. I'm very pleased that i am able to contribute something. ☺ Jul 12, 2019 at 8:53
  • 1
    I've just pushed a new version to pypi (v0.4.1) - this issue should now be fixed. Jul 14, 2019 at 8:28

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