Improve import alias support (#1133)

* Improve import alias
- Fix #962
- Fix #1106
- Fix #1067

slither/core/declarations/import_directive.py

@@ -1,5 +1,5 @@
 from pathlib import Path
-from typing import Optional, TYPE_CHECKING
+from typing import Optional, TYPE_CHECKING, Dict
 
 from slither.core.source_mapping.source_mapping import SourceMapping
 
@@ -13,6 +13,8 @@ class Import(SourceMapping):
         self._filename: Path = filename
         self._alias: Optional[str] = None
         self.scope: "FileScope" = scope
+        # Map local name -> original name
+        self.renaming: Dict[str, str] = {}
 
     @property
     def filename(self) -> str:

slither/core/scope/scope.py

@@ -39,6 +39,11 @@ class FileScope:
         self.structures: Dict[str, StructureTopLevel] = {}
         self.variables: Dict[str, TopLevelVariable] = {}
 
+        # Renamed created by import
+        # import A as B
+        # local name -> original name (A -> B)
+        self.renaming: Dict[str, str] = {}
+
     def add_accesible_scopes(self) -> bool:
         """
         Add information from accessible scopes. Return true if new information was obtained
@@ -74,6 +79,9 @@ class FileScope:
             if not _dict_contain(new_scope.variables, self.variables):
                 self.variables.update(new_scope.variables)
                 learn_something = True
+            if not _dict_contain(new_scope.renaming, self.renaming):
+                self.renaming.update(new_scope.renaming)
+                learn_something = True
 
         return learn_something
 

slither/solc_parsing/expressions/find_variable.py

@@ -334,6 +334,9 @@ def find_variable(
     # Because functions are copied between contracts, two functions can have the same ref
     # So we need to first look with respect to the direct context
 
+    if var_name in current_scope.renaming:
+        var_name = current_scope.renaming[var_name]
+
     # Use ret0/ret1 to help mypy
     ret0 = _find_variable_from_ref_declaration(
         referenced_declaration, direct_contracts, direct_functions

slither/solc_parsing/slither_compilation_unit_solc.py

@@ -14,6 +14,7 @@ from slither.core.declarations.function_top_level import FunctionTopLevel
 from slither.core.declarations.import_directive import Import
 from slither.core.declarations.pragma_directive import Pragma
 from slither.core.declarations.structure_top_level import StructureTopLevel
+from slither.core.scope.scope import FileScope
 from slither.core.variables.top_level_variable import TopLevelVariable
 from slither.exceptions import SlitherException
 from slither.solc_parsing.declarations.contract import ContractSolc
@@ -28,6 +29,33 @@ logger = logging.getLogger("SlitherSolcParsing")
 logger.setLevel(logging.INFO)
 
 
+def _handle_import_aliases(
+    symbol_aliases: Dict, import_directive: Import, scope: FileScope
+) -> None:
+    """
+    Handle the parsing of import aliases
+
+    Args:
+        symbol_aliases (Dict): json dict from solc
+        import_directive (Import): current import directive
+        scope (FileScope): current file scape
+
+    Returns:
+
+    """
+    for symbol_alias in symbol_aliases:
+        if (
+            "foreign" in symbol_alias
+            and "name" in symbol_alias["foreign"]
+            and "local" in symbol_alias
+        ):
+            original_name = symbol_alias["foreign"]["name"]
+            local_name = symbol_alias["local"]
+            import_directive.renaming[local_name] = original_name
+            # Assuming that two imports cannot collide in renaming
+            scope.renaming[local_name] = original_name
+
+
 class SlitherCompilationUnitSolc:
     # pylint: disable=no-self-use,too-many-instance-attributes
     def __init__(self, compilation_unit: SlitherCompilationUnit):
@@ -204,6 +232,9 @@ class SlitherCompilationUnitSolc:
                     # TODO investigate unitAlias in version < 0.7 and legacy ast
                     if "unitAlias" in top_level_data:
                         import_directive.alias = top_level_data["unitAlias"]
+                    if "symbolAliases" in top_level_data:
+                        symbol_aliases = top_level_data["symbolAliases"]
+                        _handle_import_aliases(symbol_aliases, import_directive, scope)
                 else:
                     import_directive = Import(
                         Path(
@@ -356,12 +387,16 @@ Please rename it, this name is reserved for Slither's internals"""
 
             for i in contract_parser.linearized_base_contracts[1:]:
                 if i in contract_parser.remapping:
-                    ancestors.append(
-                        contract_parser.underlying_contract.file_scope.get_contract_from_name(
-                            contract_parser.remapping[i]
-                        )
-                        # self._compilation_unit.get_contract_from_name(contract_parser.remapping[i])
+                    contract_name = contract_parser.remapping[i]
+                    if contract_name in contract_parser.underlying_contract.file_scope.renaming:
+                        contract_name = contract_parser.underlying_contract.file_scope.renaming[
+                            contract_name
+                        ]
+                    target = contract_parser.underlying_contract.file_scope.get_contract_from_name(
+                        contract_name
                     )
+                    assert target
+                    ancestors.append(target)
                 elif i in self._contracts_by_id:
                     ancestors.append(self._contracts_by_id[i])
                 else:

slither/solc_parsing/solidity_types/type_parsing.py

@@ -223,6 +223,7 @@ def parse_type(
     from slither.solc_parsing.variables.top_level_variable import TopLevelVariableSolc
 
     sl: "SlitherCompilationUnit"
+    renaming: Dict[str, str]
     # Note: for convenicence top level functions use the same parser than function in contract
     # but contract_parser is set to None
     if isinstance(caller_context, SlitherCompilationUnitSolc) or (
@@ -232,10 +233,12 @@ def parse_type(
         if isinstance(caller_context, SlitherCompilationUnitSolc):
             sl = caller_context.compilation_unit
             next_context = caller_context
+            renaming = {}
         else:
             assert isinstance(caller_context, FunctionSolc)
             sl = caller_context.underlying_function.compilation_unit
             next_context = caller_context.slither_parser
+            renaming = caller_context.underlying_function.file_scope.renaming
         structures_direct_access = sl.structures_top_level
         all_structuress = [c.structures for c in sl.contracts]
         all_structures = [item for sublist in all_structuress for item in sublist]
@@ -269,6 +272,8 @@ def parse_type(
         all_enums = scope.enums.values()
         contracts = scope.contracts.values()
         functions = list(scope.functions)
+
+        renaming = scope.renaming
     elif isinstance(caller_context, (ContractSolc, FunctionSolc)):
         if isinstance(caller_context, FunctionSolc):
             underlying_func = caller_context.underlying_function
@@ -277,9 +282,11 @@ def parse_type(
             assert isinstance(underlying_func, FunctionContract)
             contract = underlying_func.contract
             next_context = caller_context.contract_parser
+            scope = caller_context.underlying_function.file_scope
         else:
             contract = caller_context.underlying_contract
             next_context = caller_context
+            scope = caller_context.underlying_contract.file_scope
 
         structures_direct_access = contract.structures
         structures_direct_access += contract.file_scope.structures.values()
@@ -293,6 +300,8 @@ def parse_type(
         all_enums += contract.file_scope.enums.values()
         contracts = contract.file_scope.contracts.values()
         functions = contract.functions + contract.modifiers
+
+        renaming = scope.renaming
     else:
         raise ParsingError(f"Incorrect caller context: {type(caller_context)}")
 
@@ -303,8 +312,11 @@ def parse_type(
         key = "name"
 
     if isinstance(t, UnknownType):
+        name = t.name
+        if name in renaming:
+            name = renaming[name]
         return _find_from_type_name(
-            t.name,
+            name,
             functions,
             contracts,
             structures_direct_access,
@@ -320,8 +332,11 @@ def parse_type(
 
     if t[key] == "UserDefinedTypeName":
         if is_compact_ast:
+            name = t["typeDescriptions"]["typeString"]
+            if name in renaming:
+                name = renaming[name]
             return _find_from_type_name(
-                t["typeDescriptions"]["typeString"],
+                name,
                 functions,
                 contracts,
                 structures_direct_access,
@@ -332,8 +347,12 @@ def parse_type(
 
         # Determine if we have a type node (otherwise we use the name node, as some older solc did not have 'type').
         type_name_key = "type" if "type" in t["attributes"] else key
+
+        name = t["attributes"][type_name_key]
+        if name in renaming:
+            name = renaming[name]
         return _find_from_type_name(
-            t["attributes"][type_name_key],
+            name,
             functions,
             contracts,
             structures_direct_access,
@@ -345,8 +364,11 @@ def parse_type(
     # Introduced with Solidity 0.8
     if t[key] == "IdentifierPath":
         if is_compact_ast:
+            name = t["name"]
+            if name in renaming:
+                name = renaming[name]
             return _find_from_type_name(
-                t["name"],
+                name,
                 functions,
                 contracts,
                 structures_direct_access,

tests/ast-parsing/complex_imports/import_aliases/import.sol

@@ -0,0 +1,14 @@
+contract Test{}
+
+
+struct St{
+    uint v;
+}
+
+uint constant A = 0;
+
+library Lib {
+    struct Data {
+        uint256 version;
+    }
+}

tests/ast-parsing/complex_imports/import_aliases/test.sol

@@ -0,0 +1,10 @@
+import {Test as TestAlias, St as StAlias, A as Aalias, Lib as LibAlias} from "./import.sol";
+
+contract C is TestAlias{
+
+    using LibAlias for LibAlias.Data;
+
+    function f(StAlias storage s) internal{
+        s.v = Aalias;
+    }
+}

tests/ast-parsing/expected/complex_imports/import_aliases/test.sol-0.8.0-compact.json

@@ -0,0 +1,7 @@
+{
+  "Test": {},
+  "Lib": {},
+  "C": {
+    "f(St)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+  }
+}

tests/ast-parsing/expected/complex_imports/import_aliases/test.sol-0.8.1-compact.json

@@ -0,0 +1,7 @@
+{
+  "Test": {},
+  "Lib": {},
+  "C": {
+    "f(St)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+  }
+}

tests/ast-parsing/expected/complex_imports/import_aliases/test.sol-0.8.10-compact.json

@@ -0,0 +1,7 @@
+{
+  "Test": {},
+  "Lib": {},
+  "C": {
+    "f(St)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+  }
+}

tests/ast-parsing/expected/complex_imports/import_aliases/test.sol-0.8.11-compact.json

@@ -0,0 +1,7 @@
+{
+  "Test": {},
+  "Lib": {},
+  "C": {
+    "f(St)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+  }
+}

tests/ast-parsing/expected/complex_imports/import_aliases/test.sol-0.8.12-compact.json

@@ -0,0 +1,7 @@
+{
+  "Test": {},
+  "Lib": {},
+  "C": {
+    "f(St)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+  }
+}

tests/ast-parsing/expected/complex_imports/import_aliases/test.sol-0.8.2-compact.json

@@ -0,0 +1,7 @@
+{
+  "Test": {},
+  "Lib": {},
+  "C": {
+    "f(St)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+  }
+}

tests/ast-parsing/expected/complex_imports/import_aliases/test.sol-0.8.3-compact.json

@@ -0,0 +1,7 @@
+{
+  "Test": {},
+  "Lib": {},
+  "C": {
+    "f(St)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+  }
+}

tests/ast-parsing/expected/complex_imports/import_aliases/test.sol-0.8.4-compact.json

@@ -0,0 +1,7 @@
+{
+  "Test": {},
+  "Lib": {},
+  "C": {
+    "f(St)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+  }
+}

tests/ast-parsing/expected/complex_imports/import_aliases/test.sol-0.8.5-compact.json

@@ -0,0 +1,7 @@
+{
+  "Test": {},
+  "Lib": {},
+  "C": {
+    "f(St)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+  }
+}

tests/ast-parsing/expected/complex_imports/import_aliases/test.sol-0.8.6-compact.json

@@ -0,0 +1,7 @@
+{
+  "Test": {},
+  "Lib": {},
+  "C": {
+    "f(St)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+  }
+}

tests/ast-parsing/expected/complex_imports/import_aliases/test.sol-0.8.7-compact.json

@@ -0,0 +1,7 @@
+{
+  "Test": {},
+  "Lib": {},
+  "C": {
+    "f(St)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+  }
+}

tests/ast-parsing/expected/complex_imports/import_aliases/test.sol-0.8.8-compact.json

@@ -0,0 +1,7 @@
+{
+  "Test": {},
+  "Lib": {},
+  "C": {
+    "f(St)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+  }
+}

tests/ast-parsing/expected/complex_imports/import_aliases/test.sol-0.8.9-compact.json

@@ -0,0 +1,7 @@
+{
+  "Test": {},
+  "Lib": {},
+  "C": {
+    "f(St)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+  }
+}

tests/test_ast_parsing.py

@@ -400,6 +400,7 @@ ALL_TESTS = [
         ["0.8.2"],
     ),
     Test("custom_error_with_state_variable.sol", make_version(8, 4, 12)),
+    Test("complex_imports/import_aliases/test.sol", VERSIONS_08),
 ]
 # create the output folder if needed
 try: