Merge pull request #2365 from crytic/dev-fix-event-parsing

Fix parsing of events

slither/core/scope/scope.py

@@ -36,11 +36,11 @@ class FileScope:
         # So we simplify the logic and have the scope fields all populated
         self.custom_errors: Set[CustomErrorTopLevel] = set()
         self.enums: Dict[str, EnumTopLevel] = {}
-        self.events: Dict[str, EventTopLevel] = {}
         # Functions is a list instead of a dict
         # Because we parse the function signature later on
         # So we simplify the logic and have the scope fields all populated
         self.functions: Set[FunctionTopLevel] = set()
+        self.events: Set[EventTopLevel] = set()
         self.using_for_directives: Set[UsingForTopLevel] = set()
         self.imports: Set[Import] = set()
         self.pragmas: Set[Pragma] = set()
@@ -76,8 +76,8 @@ class FileScope:
             if not _dict_contain(new_scope.enums, self.enums):
                 self.enums.update(new_scope.enums)
                 learn_something = True
-            if not _dict_contain(new_scope.events, self.events):
+            if not new_scope.events.issubset(self.events):
-                self.events.update(new_scope.events)
+                self.events |= new_scope.events
                 learn_something = True
             if not new_scope.functions.issubset(self.functions):
                 self.functions |= new_scope.functions

slither/solc_parsing/declarations/contract.py

@@ -16,7 +16,7 @@ from slither.core.solidity_types import ElementaryType, TypeAliasContract
 from slither.core.variables.state_variable import StateVariable
 from slither.solc_parsing.declarations.caller_context import CallerContextExpression
 from slither.solc_parsing.declarations.custom_error import CustomErrorSolc
-from slither.solc_parsing.declarations.event import EventSolc
+from slither.solc_parsing.declarations.event_contract import EventContractSolc
 from slither.solc_parsing.declarations.function import FunctionSolc
 from slither.solc_parsing.declarations.modifier import ModifierSolc
 from slither.solc_parsing.declarations.structure_contract import StructureContractSolc
@@ -751,7 +751,7 @@ class ContractSolc(CallerContextExpression):
                 event.set_contract(self._contract)
                 event.set_offset(event_to_parse["src"], self._contract.compilation_unit)
 
-                event_parser = EventSolc(event, event_to_parse, self._slither_parser)  # type: ignore
+                event_parser = EventContractSolc(event, event_to_parse, self)  # type: ignore
                 event_parser.analyze()  # type: ignore
                 self._contract.events_as_dict[event.full_name] = event
         except (VariableNotFound, KeyError) as e:

slither/solc_parsing/declarations/event_contract.py

@@ -1,27 +1,27 @@
 """
-    Event module
+    EventContract module
 """
 from typing import TYPE_CHECKING, Dict
 
 from slither.core.variables.event_variable import EventVariable
 from slither.solc_parsing.variables.event_variable import EventVariableSolc
-from slither.core.declarations.event import Event
+from slither.core.declarations.event_contract import EventContract
 
 if TYPE_CHECKING:
-    from slither.solc_parsing.slither_compilation_unit_solc import SlitherCompilationUnitSolc
+    from slither.solc_parsing.declarations.contract import ContractSolc
 
 
-class EventSolc:
+class EventContractSolc:
     """
-    Event class
+    EventContract class
     """
 
     def __init__(
-        self, event: Event, event_data: Dict, slither_parser: "SlitherCompilationUnitSolc"
+        self, event: EventContract, event_data: Dict, contract_parser: "ContractSolc"
     ) -> None:
 
         self._event = event
-        self._slither_parser = slither_parser
+        self._contract_parser = contract_parser
 
         if self.is_compact_ast:
             self._event.name = event_data["name"]
@@ -42,16 +42,16 @@ class EventSolc:
 
     @property
     def is_compact_ast(self) -> bool:
-        return self._slither_parser.is_compact_ast
+        return self._contract_parser.is_compact_ast
 
     def analyze(self) -> None:
         for elem_to_parse in self._elemsNotParsed:
             elem = EventVariable()
             # Todo: check if the source offset is always here
             if "src" in elem_to_parse:
-                elem.set_offset(elem_to_parse["src"], self._slither_parser.compilation_unit)
+                elem.set_offset(elem_to_parse["src"], self._contract_parser.compilation_unit)
             elem_parser = EventVariableSolc(elem, elem_to_parse)
-            elem_parser.analyze(self._slither_parser)
+            elem_parser.analyze(self._contract_parser)
 
             self._event.elems.append(elem)
 

slither/solc_parsing/declarations/event_top_level.py

@@ -0,0 +1,75 @@
+"""
+    EventTopLevel module
+"""
+from typing import TYPE_CHECKING, Dict
+
+from slither.core.declarations.event_top_level import EventTopLevel
+from slither.core.variables.event_variable import EventVariable
+from slither.core.compilation_unit import SlitherCompilationUnit
+from slither.solc_parsing.variables.event_variable import EventVariableSolc
+from slither.solc_parsing.declarations.caller_context import CallerContextExpression
+
+if TYPE_CHECKING:
+    from slither.solc_parsing.slither_compilation_unit_solc import SlitherCompilationUnitSolc
+
+
+class EventTopLevelSolc(CallerContextExpression):
+    """
+    EventTopLevel class
+    """
+
+    def __init__(
+        self, event: EventTopLevel, event_data: Dict, slither_parser: "SlitherCompilationUnitSolc"
+    ) -> None:
+
+        self._event = event
+        self._slither_parser = slither_parser
+
+        if self.is_compact_ast:
+            self._event.name = event_data["name"]
+            elems = event_data["parameters"]
+            assert elems["nodeType"] == "ParameterList"
+            self._elemsNotParsed = elems["parameters"]
+        else:
+            self._event.name = event_data["attributes"]["name"]
+            for elem in event_data["children"]:
+                # From Solidity 0.6.3 to 0.6.10 (included)
+                # Comment above a event might be added in the children
+                # of an event for the legacy ast
+                if elem["name"] == "ParameterList":
+                    if "children" in elem:
+                        self._elemsNotParsed = elem["children"]
+                    else:
+                        self._elemsNotParsed = []
+
+    def analyze(self) -> None:
+        for elem_to_parse in self._elemsNotParsed:
+            elem = EventVariable()
+            # Todo: check if the source offset is always here
+            if "src" in elem_to_parse:
+                elem.set_offset(elem_to_parse["src"], self._slither_parser.compilation_unit)
+            elem_parser = EventVariableSolc(elem, elem_to_parse)
+            elem_parser.analyze(self)
+
+            self._event.elems.append(elem)
+
+        self._elemsNotParsed = []
+
+    @property
+    def is_compact_ast(self) -> bool:
+        return self._slither_parser.is_compact_ast
+
+    @property
+    def compilation_unit(self) -> SlitherCompilationUnit:
+        return self._slither_parser.compilation_unit
+
+    def get_key(self) -> str:
+        return self._slither_parser.get_key()
+
+    @property
+    def slither_parser(self) -> "SlitherCompilationUnitSolc":
+        return self._slither_parser
+
+    @property
+    def underlying_event(self) -> EventTopLevel:
+        return self._event

slither/solc_parsing/expressions/find_variable.py

@@ -134,8 +134,9 @@ def find_top_level(
     if var_name in scope.enums:
         return scope.enums[var_name], False
 
-    if var_name in scope.events:
+    for event in scope.events:
-        return scope.events[var_name], False
+        if var_name == event.full_name:
+            return event, False
 
     for import_directive in scope.imports:
         if import_directive.alias == var_name:
@@ -268,6 +269,7 @@ def _find_variable_init(
     from slither.solc_parsing.declarations.function import FunctionSolc
     from slither.solc_parsing.declarations.structure_top_level import StructureTopLevelSolc
     from slither.solc_parsing.variables.top_level_variable import TopLevelVariableSolc
+    from slither.solc_parsing.declarations.event_top_level import EventTopLevelSolc
     from slither.solc_parsing.declarations.custom_error import CustomErrorSolc
 
     direct_contracts: List[Contract]
@@ -311,6 +313,10 @@ def _find_variable_init(
         direct_contracts = []
         direct_functions_parser = []
         scope = caller_context.underlying_variable.file_scope
+    elif isinstance(caller_context, EventTopLevelSolc):
+        direct_contracts = []
+        direct_functions_parser = []
+        scope = caller_context.underlying_event.file_scope
     elif isinstance(caller_context, CustomErrorSolc):
         if caller_context.contract_parser:
             direct_contracts = [caller_context.contract_parser.underlying_contract]

slither/solc_parsing/slither_compilation_unit_solc.py

@@ -24,7 +24,7 @@ from slither.solc_parsing.declarations.caller_context import CallerContextExpres
 from slither.solc_parsing.declarations.contract import ContractSolc
 from slither.solc_parsing.declarations.custom_error import CustomErrorSolc
 from slither.solc_parsing.declarations.function import FunctionSolc
-from slither.solc_parsing.declarations.event import EventSolc
+from slither.solc_parsing.declarations.event_top_level import EventTopLevelSolc
 from slither.solc_parsing.declarations.structure_top_level import StructureTopLevelSolc
 from slither.solc_parsing.declarations.using_for_top_level import UsingForTopLevelSolc
 from slither.solc_parsing.exceptions import VariableNotFound
@@ -90,6 +90,7 @@ class SlitherCompilationUnitSolc(CallerContextExpression):
         self._variables_top_level_parser: List[TopLevelVariableSolc] = []
         self._functions_top_level_parser: List[FunctionSolc] = []
         self._using_for_top_level_parser: List[UsingForTopLevelSolc] = []
+        self._events_top_level_parser: List[EventTopLevelSolc] = []
         self._all_functions_and_modifier_parser: List[FunctionSolc] = []
 
         self._top_level_contracts_counter = 0
@@ -353,9 +354,9 @@ class SlitherCompilationUnitSolc(CallerContextExpression):
                 event = EventTopLevel(scope)
                 event.set_offset(top_level_data["src"], self._compilation_unit)
 
-                event_parser = EventSolc(event, top_level_data, self)  # type: ignore
+                event_parser = EventTopLevelSolc(event, top_level_data, self)  # type: ignore
-                event_parser.analyze()  # type: ignore
+                self._events_top_level_parser.append(event_parser)
-                scope.events[event.full_name] = event
+                scope.events.add(event)
                 self._compilation_unit.events_top_level.append(event)
 
             else:
@@ -612,6 +613,7 @@ Please rename it, this name is reserved for Slither's internals"""
 
         self._analyze_top_level_variables()
         self._analyze_top_level_structures()
+        self._analyze_top_level_events()
 
         # Start with the contracts without inheritance
         # Analyze a contract only if all its fathers
@@ -722,6 +724,13 @@ Please rename it, this name is reserved for Slither's internals"""
         except (VariableNotFound, KeyError) as e:
             raise SlitherException(f"Missing {e} during variable analyze") from e
 
+    def _analyze_top_level_events(self) -> None:
+        try:
+            for event in self._events_top_level_parser:
+                event.analyze()
+        except (VariableNotFound, KeyError) as e:
+            raise SlitherException(f"Missing event {e} during top level event analyze") from e
+
     def _analyze_params_top_level_function(self) -> None:
         for func_parser in self._functions_top_level_parser:
             func_parser.analyze_params()

slither/solc_parsing/solidity_types/type_parsing.py

@@ -232,6 +232,7 @@ def parse_type(
     from slither.solc_parsing.declarations.structure_top_level import StructureTopLevelSolc
     from slither.solc_parsing.slither_compilation_unit_solc import SlitherCompilationUnitSolc
     from slither.solc_parsing.variables.top_level_variable import TopLevelVariableSolc
+    from slither.solc_parsing.declarations.event_top_level import EventTopLevelSolc
 
     sl: "SlitherCompilationUnit"
     renaming: Dict[str, str]
@@ -266,7 +267,13 @@ def parse_type(
         functions = []
     elif isinstance(
         caller_context,
-        (StructureTopLevelSolc, CustomErrorSolc, TopLevelVariableSolc, UsingForTopLevelSolc),
+        (
+            StructureTopLevelSolc,
+            CustomErrorSolc,
+            TopLevelVariableSolc,
+            UsingForTopLevelSolc,
+            EventTopLevelSolc,
+        ),
     ):
         if isinstance(caller_context, StructureTopLevelSolc):
             scope = caller_context.underlying_structure.file_scope
@@ -274,6 +281,8 @@ def parse_type(
             scope = caller_context.underlying_variable.file_scope
         elif isinstance(caller_context, UsingForTopLevelSolc):
             scope = caller_context.underlying_using_for.file_scope
+        elif isinstance(caller_context, EventTopLevelSolc):
+            scope = caller_context.underlying_event.file_scope
         else:
             assert isinstance(caller_context, CustomErrorSolc)
             custom_error = caller_context.underlying_custom_error

tests/e2e/solc_parsing/test_data/event-top-level.sol

@@ -1,7 +1,17 @@
 event MyEvent(uint256 a);
 
+uint256 constant A = 3;
+event MyEvent2(uint8[A]);
+
 contract T {
+  type MyType is uint256;
+  event MyCustomEvent(MyType mytype);
+
   function a() public {
     emit MyEvent(2);
   }
+
+  function b() public {
+    emit MyEvent2([1,2,3]);
+  }
 }

tests/e2e/solc_parsing/test_data/expected/event-top-level.sol-0.8.22-compact.json

@@ -1,5 +1,6 @@
 {
   "T": {
-    "a()": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
+    "a()": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n",
+    "b()": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: EXPRESSION 1\n\"];\n}\n"
   }
 }