Consensys / python-solidity-parser

An experimental Solidity parser for Python built on top of a robust ANTLR4 grammar 📚
https://pypi.org/project/solidity-parser/
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antlr parser python python3 solidity

python-solidity-parser

An experimental Solidity parser for Python built on top of a robust ANTLR4 grammar.

This is a python3 port of the javascript antlr parser maintained by @federicobond. Interfaces are intentionally following the javascript implementation and are therefore not pep8 compliant.

Install

#> pip3 install solidity_parser
#> python3 -m solidity_parser <parse|outline> <path_to_contract.sol>   # print parse tree or sourceUnit outline

HowTo


import sys
import pprint

from solidity_parser import parser

sourceUnit = parser.parse_file(sys.argv[1], loc=False) # loc=True -> add location information to ast nodes
pprint.pprint(sourceUnit)  
# see output below

output:

{'type': 'SourceUnit',
 'children': [{'type': 'PragmaDirective',
               'name': 'solidity',
               'value': '^0.4.22'},
              {'type': 'ContractDefinition'},
               'baseContracts': [],
               'kind': 'contract',
               'name': 'SimpleAuction',
               'subNodes': [{'initialValue': None,
                             'type': 'StateVariableDeclaration',
                             'variables': [{'expression': None,
                                            'isDeclaredConst': False,
                                            'isIndexed': False,
                                            'isStateVar': True,
                                            'name': 'beneficiary',
                                            'type': 'VariableDeclaration',
                                            'typeName': {'name': 'address',
                                                         'type': 'ElementaryTypeName'},
                                            'visibility': 'public'}]},
...

Nodes

Parse-tree nodes can be accessed both like dictionaries or via object attributes. Nodes always carry a type field to hint the type of AST node. The start node is always of type sourceUnit.

Accessing AST items in an Object Oriented fashion

# ... continuing from previous snippet

# subparse into objects for nicer interfaces:
# create a nested object structure from AST
sourceUnitObject = parser.objectify(sourceUnit)

# access imports, contracts, functions, ...  (see outline example in __main__.py)
sourceUnitObject.imports  # []
sourceUnitObject.pragmas  # []
sourceUnitObject.contracts.keys()  # get all contract names
sourceUnitObject.contracts["contractName"].functions.keys()  # get all functions in contract: "contractName"
sourceUnitObject.contracts["contractName"].functions["myFunction"].visibility  # get "myFunction"s visibility (or stateMutability)

Generate the parser

Update the grammar in ./solidity-antlr4/Solidity.g4 and run the antlr generator script to create the parser classes in solidity_parser/solidity_antlr4.

#> bash script/antlr4.sh