function arguments, return value type added

Author: priyankabose

slither/analyses/data_dependency/data_dependency.py

@@ -293,33 +293,39 @@ def get_all_dependencies_ssa(
     return context.context[KEY_SSA]
 
 
-def get_must_depends_on(x):
-    must_dependencies = compute_must_dependencies(x)
+def get_must_depends_on(variable: SUPPORTED_TYPES) -> SUPPORTED_TYPES | None:
+    """
+    Return must dependency of a variable if exist otherwise return None.
+
+    :param variable: target variable whose must dependency needs to be computed
+    :return: Variable | None
+    """
+    must_dependencies = compute_must_dependencies(variable)
     if len(must_dependencies) > 1 or len(must_dependencies) == 0:
         return None
     return list(must_dependencies)[0]
 
 
-def compute_must_dependencies(x):
-    if isinstance(x, (SolidityVariableComposed, Constant)) or (
-        x.function.visibility in ["public", "external"] and x in x.function.parameters
+def compute_must_dependencies(v:SUPPORTED_TYPES) -> Set[Variable]:
+    if isinstance(v, (SolidityVariableComposed, Constant)) or (
+        v.function.visibility in ["public", "external"] and v in v.function.parameters
     ):
-        return set([x])
+        return set([v])
 
     function_dependencies = {}
     function_dependencies["context"] = {}
     lvalues = []
 
-    for node in x.function.nodes:
+    for node in v.function.nodes:
         for ir in node.irs_ssa:
             if isinstance(ir, OperationWithLValue) and ir.lvalue:
                 if isinstance(ir.lvalue, LocalIRVariable) and ir.lvalue.is_storage:
                     continue
                 if isinstance(ir.lvalue, ReferenceVariable):
                     lvalue = ir.lvalue.points_to
                     if lvalue:
-                        lvalues.append((lvalue, x.function, ir))
-                lvalues.append((ir.lvalue, x.function, ir))
+                        lvalues.append((lvalue, v.function, ir))
+                lvalues.append((ir.lvalue, v.function, ir))
 
     for lvalue_details in lvalues:
         lvalue = lvalue_details[0]
@@ -335,14 +341,14 @@ def compute_must_dependencies(x):
             read = ir.function.return_values_ssa
         else:
             read = ir.read
-        for v in read:
-            # if not isinstance(v, Constant):
-            function_dependencies["context"][lvalue].add(v)
+        for variable in read:
+            # if not isinstance(variable, Constant):
+            function_dependencies["context"][lvalue].add(variable)
     function_dependencies["context"] = convert_to_non_ssa(function_dependencies["context"])
 
     must_dependencies = set()
     data_dependencies = (
-        list(function_dependencies["context"][x])
+        list(function_dependencies["context"][v])
         if function_dependencies["context"] is not None
         else []
     )
@@ -354,7 +360,6 @@ def compute_must_dependencies(x):
             must_dependencies = must_dependencies.union(result)
     return must_dependencies
 
-
 # endregion
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