Improve slither-flat (#1125)

* Improve slither-flat
- Better support of multiple compilation unit
- Better support if there are multiple contracts with the same name
- Better support of top level object (partially fix #955). The support
for the local import strategy is missing

slither/core/declarations/contract.py

@@ -75,7 +75,7 @@ class Contract(SourceMapping):  # pylint: disable=too-many-public-methods
         self._custom_errors: Dict[str, "CustomErrorContract"] = {}
 
         # The only str is "*"
-        self._using_for: Dict[Union[str, Type], List[str]] = {}
+        self._using_for: Dict[Union[str, Type], List[Type]] = {}
         self._kind: Optional[str] = None
         self._is_interface: bool = False
 
@@ -245,7 +245,7 @@ class Contract(SourceMapping):  # pylint: disable=too-many-public-methods
     ###################################################################################
 
     @property
-    def using_for(self) -> Dict[Union[str, Type], List[str]]:
+    def using_for(self) -> Dict[Union[str, Type], List[Type]]:
         return self._using_for
 
     # endregion

slither/solc_parsing/solidity_types/type_parsing.py

@@ -198,7 +198,7 @@ def _find_from_type_name(  # pylint: disable=too-many-locals,too-many-branches,t
 def parse_type(
     t: Union[Dict, UnknownType],
     caller_context: Union[CallerContextExpression, "SlitherCompilationUnitSolc"],
-):
+) -> Type:
     """
     caller_context can be a SlitherCompilationUnitSolc because we recursively call the function
     and go up in the context's scope. If we are really lost we just go over the SlitherCompilationUnitSolc

slither/tools/flattening/__main__.py

@@ -104,8 +104,11 @@ def main():
     args = parse_args()
 
     slither = Slither(args.filename, **vars(args))
+
+    for compilation_unit in slither.compilation_units:
+
         flat = Flattening(
-        slither,
+            compilation_unit,
             external_to_public=args.convert_external,
             remove_assert=args.remove_assert,
             private_to_internal=args.convert_private,

slither/tools/flattening/flattening.py

@@ -1,17 +1,21 @@
 import logging
 import re
+import uuid
 from collections import namedtuple
 from enum import Enum as PythonEnum
 from pathlib import Path
 from typing import List, Set, Dict, Optional
 
+from slither.core.compilation_unit import SlitherCompilationUnit
 from slither.core.declarations import SolidityFunction, EnumContract, StructureContract
 from slither.core.declarations.contract import Contract
-from slither.core.slither_core import SlitherCore
+from slither.core.declarations.function_top_level import FunctionTopLevel
+from slither.core.declarations.top_level import TopLevel
 from slither.core.solidity_types import MappingType, ArrayType
+from slither.core.solidity_types.type import Type
 from slither.core.solidity_types.user_defined_type import UserDefinedType
 from slither.exceptions import SlitherException
-from slither.slithir.operations import NewContract, TypeConversion, SolidityCall
+from slither.slithir.operations import NewContract, TypeConversion, SolidityCall, InternalCall
 from slither.tools.flattening.export.export import (
     Export,
     export_as_json,
@@ -44,7 +48,7 @@ class Flattening:
     # pylint: disable=too-many-instance-attributes,too-many-arguments,too-many-locals,too-few-public-methods
     def __init__(
         self,
-        slither: SlitherCore,
+        compilation_unit: SlitherCompilationUnit,
         external_to_public=False,
         remove_assert=False,
         private_to_internal=False,
@@ -52,7 +56,8 @@ class Flattening:
         pragma_solidity: Optional[str] = None,
     ):
         self._source_codes: Dict[Contract, str] = {}
-        self._slither: SlitherCore = slither
+        self._source_codes_top_level: Dict[TopLevel, str] = {}
+        self._compilation_unit: SlitherCompilationUnit = compilation_unit
         self._external_to_public = external_to_public
         self._remove_assert = remove_assert
         self._use_abi_encoder_v2 = False
@@ -63,17 +68,29 @@ class Flattening:
 
         self._check_abi_encoder_v2()
 
-        for contract in slither.contracts:
+        for contract in compilation_unit.contracts:
             self._get_source_code(contract)
 
+        self._get_source_code_top_level(compilation_unit.structures_top_level)
+        self._get_source_code_top_level(compilation_unit.enums_top_level)
+        self._get_source_code_top_level(compilation_unit.variables_top_level)
+        self._get_source_code_top_level(compilation_unit.functions_top_level)
+
+    def _get_source_code_top_level(self, elems: List[TopLevel]) -> None:
+        for elem in elems:
+            src_mapping = elem.source_mapping
+            content = self._compilation_unit.core.source_code[src_mapping["filename_absolute"]]
+            start = src_mapping["start"]
+            end = src_mapping["start"] + src_mapping["length"]
+            self._source_codes_top_level[elem] = content[start:end]
+
     def _check_abi_encoder_v2(self):
         """
         Check if ABIEncoderV2 is required
         Set _use_abi_encorder_v2
         :return:
         """
-        for compilation_unit in self._slither.compilation_units:
+        for p in self._compilation_unit.pragma_directives:
-            for p in compilation_unit.pragma_directives:
             if "ABIEncoderV2" in str(p.directive):
                 self._use_abi_encoder_v2 = True
                 return
@@ -88,7 +105,7 @@ class Flattening:
         :return:
         """
         src_mapping = contract.source_mapping
-        content = self._slither.source_code[src_mapping["filename_absolute"]]
+        content = self._compilation_unit.core.source_code[src_mapping["filename_absolute"]]
         start = src_mapping["start"]
         end = src_mapping["start"] + src_mapping["length"]
 
@@ -132,11 +149,9 @@ class Flattening:
         if self._private_to_internal:
             for variable in contract.state_variables_declared:
                 if variable.visibility == "private":
-                    print(variable.source_mapping)
                     attributes_start = variable.source_mapping["start"]
                     attributes_end = attributes_start + variable.source_mapping["length"]
                     attributes = content[attributes_start:attributes_end]
-                    print(attributes)
                     regex = re.search(r" private ", attributes)
                     if regex:
                         to_patch.append(
@@ -191,35 +206,54 @@ class Flattening:
             ret += f"pragma solidity {self._pragma_solidity};\n"
         else:
             # TODO support multiple compiler version
-            ret += f"pragma solidity {list(self._slither.crytic_compile.compilation_units.values())[0].compiler_version.version};\n"
+            ret += f"pragma solidity {list(self._compilation_unit.crytic_compile.compilation_units.values())[0].compiler_version.version};\n"
 
         if self._use_abi_encoder_v2:
             ret += "pragma experimental ABIEncoderV2;\n"
         return ret
 
-    def _export_from_type(self, t, contract, exported, list_contract):
+    def _export_from_type(
+        self,
+        t: Type,
+        contract: Contract,
+        exported: Set[str],
+        list_contract: List[Contract],
+        list_top_level: List[TopLevel],
+    ):
         if isinstance(t, UserDefinedType):
-            if isinstance(t.type, (EnumContract, StructureContract)):
+            t_type = t.type
-                if t.type.contract != contract and t.type.contract not in exported:
+            if isinstance(t_type, (EnumContract, StructureContract)):
-                    self._export_list_used_contracts(t.type.contract, exported, list_contract)
+                if t_type.contract != contract and t_type.contract not in exported:
+                    self._export_list_used_contracts(
+                        t_type.contract, exported, list_contract, list_top_level
+                    )
             else:
                 assert isinstance(t.type, Contract)
                 if t.type != contract and t.type not in exported:
-                    self._export_list_used_contracts(t.type, exported, list_contract)
+                    self._export_list_used_contracts(
+                        t.type, exported, list_contract, list_top_level
+                    )
         elif isinstance(t, MappingType):
-            self._export_from_type(t.type_from, contract, exported, list_contract)
+            self._export_from_type(t.type_from, contract, exported, list_contract, list_top_level)
-            self._export_from_type(t.type_to, contract, exported, list_contract)
+            self._export_from_type(t.type_to, contract, exported, list_contract, list_top_level)
         elif isinstance(t, ArrayType):
-            self._export_from_type(t.type, contract, exported, list_contract)
+            self._export_from_type(t.type, contract, exported, list_contract, list_top_level)
 
     def _export_list_used_contracts(  # pylint: disable=too-many-branches
-        self, contract: Contract, exported: Set[str], list_contract: List[Contract]
+        self,
+        contract: Contract,
+        exported: Set[str],
+        list_contract: List[Contract],
+        list_top_level: List[TopLevel],
     ):
+        # TODO: investigate why this happen
+        if not isinstance(contract, Contract):
+            return
         if contract.name in exported:
             return
         exported.add(contract.name)
         for inherited in contract.inheritance:
-            self._export_list_used_contracts(inherited, exported, list_contract)
+            self._export_list_used_contracts(inherited, exported, list_contract, list_top_level)
 
         # Find all the external contracts called
         externals = contract.all_library_calls + contract.all_high_level_calls
@@ -228,7 +262,16 @@ class Flattening:
         externals = list({e[0] for e in externals if e[0] != contract})
 
         for inherited in externals:
-            self._export_list_used_contracts(inherited, exported, list_contract)
+            self._export_list_used_contracts(inherited, exported, list_contract, list_top_level)
+
+        for list_libs in contract.using_for.values():
+            for lib_candidate_type in list_libs:
+                if isinstance(lib_candidate_type, UserDefinedType):
+                    lib_candidate = lib_candidate_type.type
+                    if isinstance(lib_candidate, Contract):
+                        self._export_list_used_contracts(
+                            lib_candidate, exported, list_contract, list_top_level
+                        )
 
         # Find all the external contracts use as a base type
         local_vars = []
@@ -236,11 +279,11 @@ class Flattening:
             local_vars += f.variables
 
         for v in contract.variables + local_vars:
-            self._export_from_type(v.type, contract, exported, list_contract)
+            self._export_from_type(v.type, contract, exported, list_contract, list_top_level)
 
         for s in contract.structures:
             for elem in s.elems.values():
-                self._export_from_type(elem.type, contract, exported, list_contract)
+                self._export_from_type(elem.type, contract, exported, list_contract, list_top_level)
 
         # Find all convert and "new" operation that can lead to use an external contract
         for f in contract.functions_declared:
@@ -248,21 +291,38 @@ class Flattening:
                 if isinstance(ir, NewContract):
                     if ir.contract_created != contract and not ir.contract_created in exported:
                         self._export_list_used_contracts(
-                            ir.contract_created, exported, list_contract
+                            ir.contract_created, exported, list_contract, list_top_level
                         )
                 if isinstance(ir, TypeConversion):
-                    self._export_from_type(ir.type, contract, exported, list_contract)
+                    self._export_from_type(
+                        ir.type, contract, exported, list_contract, list_top_level
+                    )
+
+                for read in ir.read:
+                    if isinstance(read, TopLevel):
+                        if read not in list_top_level:
+                            list_top_level.append(read)
+                if isinstance(ir, InternalCall):
+                    function_called = ir.function
+                    if isinstance(function_called, FunctionTopLevel):
+                        list_top_level.append(function_called)
+
         if contract not in list_contract:
             list_contract.append(contract)
 
     def _export_contract_with_inheritance(self, contract) -> Export:
         list_contracts: List[Contract] = []  # will contain contract itself
-        self._export_list_used_contracts(contract, set(), list_contracts)
+        list_top_level: List[TopLevel] = []
-        path = Path(self._export_path, f"{contract.name}.sol")
+        self._export_list_used_contracts(contract, set(), list_contracts, list_top_level)
+        path = Path(self._export_path, f"{contract.name}_{uuid.uuid4()}.sol")
 
         content = ""
         content += self._pragmas()
 
+        for listed_top_level in list_top_level:
+            content += self._source_codes_top_level[listed_top_level]
+            content += "\n"
+
         for listed_contract in list_contracts:
             content += self._source_codes[listed_contract]
             content += "\n"
@@ -271,7 +331,7 @@ class Flattening:
 
     def _export_most_derived(self) -> List[Export]:
         ret: List[Export] = []
-        for contract in self._slither.contracts_derived:
+        for contract in self._compilation_unit.contracts_derived:
             ret.append(self._export_contract_with_inheritance(contract))
         return ret
 
@@ -281,8 +341,13 @@ class Flattening:
         content = ""
         content += self._pragmas()
 
+        for top_level_content in self._source_codes_top_level.values():
+            content += "\n"
+            content += top_level_content
+            content += "\n"
+
         contract_seen = set()
-        contract_to_explore = list(self._slither.contracts)
+        contract_to_explore = list(self._compilation_unit.contracts)
 
         # We only need the inheritance order here, as solc can compile
         # a contract that use another contract type (ex: state variable) that he has not seen yet
@@ -303,9 +368,17 @@ class Flattening:
 
     def _export_with_import(self) -> List[Export]:
         exports: List[Export] = []
-        for contract in self._slither.contracts:
+        for contract in self._compilation_unit.contracts:
             list_contracts: List[Contract] = []  # will contain contract itself
-            self._export_list_used_contracts(contract, set(), list_contracts)
+            list_top_level: List[TopLevel] = []
+            self._export_list_used_contracts(contract, set(), list_contracts, list_top_level)
+
+            if list_top_level:
+                logger.info(
+                    "Top level objects are not yet supported with the local import flattening"
+                )
+                for elem in list_top_level:
+                    logger.info(f"Missing {elem} for {contract.name}")
 
             path = Path(self._export_path, f"{contract.name}.sol")
 
@@ -341,12 +414,13 @@ class Flattening:
             elif strategy == Strategy.LocalImport:
                 exports = self._export_with_import()
         else:
-            contracts = self._slither.get_contract_from_name(target)
+            contracts = self._compilation_unit.get_contract_from_name(target)
-            if len(contracts) != 1:
+            if len(contracts) == 0:
                 logger.error(f"{target} not found")
                 return
-            contract = contracts[0]
+            exports = []
-            exports = [self._export_contract_with_inheritance(contract)]
+            for contract in contracts:
+                exports.append(self._export_contract_with_inheritance(contract))
 
         if json:
             export_as_json(exports, json)