Handle edge case when parsing (#1826)

* Change configuration

* Downgrade solcx

* Handle edge case when parsing

Author: norhh

mythril/ethereum/util.py

@@ -156,7 +156,7 @@ def parse_pragma(solidity_code):
     max_version = Optional(inequality + version)
     pragma = Word("pragma") + Word("solidity") + min_version + Optional(max_version)
     result = pragma.parseString(solidity_code)
-    min_inequality = result[2] if result[2] in [">", "<", ">=", "<="] else ""
+    min_inequality = result[2] if result[2] in [">", "<", ">=", "<=", "="] else ""
     min_carrot = result[2] if result[2] == "^" else ""
     min_version = result[3] if min_carrot != "" or min_inequality != "" else result[2]
     return {

tests/util_tests.py

@@ -5,6 +5,7 @@
 
 test_data = (
     ("pragma solidity 0.5.0\n", ["0.5.0"]),
+    ("pragma solidity =0.5.0\n", ["0.5.0"]),
     ("pragma solidity ^0.4.26\n", ["0.4.26"]),
     ("pragma solidity ^0.6.3;\n", [f"0.6.{x}" for x in range(3, 13)]),
     ("pragma solidity ^0.6.3              ;\n", [f"0.6.{x}" for x in range(3, 13)]),