Add more test cases to test_implicit_returns.py

tests/unit/slithir/test_implicit_returns.py

@@ -10,7 +10,7 @@ from slither.slithir.operations import (
 )
 
 
-def test_named_return_with_explicit_return(slither_from_source) -> None:
+def test_with_explicit_return(slither_from_source) -> None:
     source = """
         contract Contract {
             function foo(int x) public returns (int y) {
@@ -40,6 +40,72 @@ def test_named_return_with_explicit_return(slither_from_source) -> None:
         assert node_ret.irs[0].values[0] == f.get_local_variable_from_name("y")
 
 
+def test_return_multiple_with_struct(slither_from_source) -> None:
+    source = """
+        struct St {
+            uint256 value;
+        }
+        
+        contract Contract {
+            function foo(St memory x) public returns (St memory y, uint256 z) {
+                z = x.value;
+                y = St({value: z + 1});
+            }
+        }
+        """
+    with slither_from_source(source) as slither:
+        c: Contract = slither.get_contract_from_name("Contract")[0]
+        f: Function = c.functions[0]
+        assert len(f.nodes) == 4
+        node = f.nodes[3]
+        assert node.type == NodeType.RETURN
+        assert isinstance(node_true.irs[0], Return)
+        assert node_true.irs[0].values[0] == f.get_local_variable_from_name("y")
+        assert node_true.irs[0].values[1] == f.get_local_variable_from_name("z")
+
+
+def test_nested_ifs_with_loop(slither_from_source) -> None:
+    source = """
+        contract Contract {
+            function foo(uint a) public returns (uint x) {
+                x = a;
+                if(a == 1) {
+                    return a;
+                } else {
+                    for (uint i = 0; i < 10; i++) {
+                        if (x > 10) {
+                            if (a < 0) {
+                                x = 10 * x;
+                            } else {
+                                throw;
+                            }
+                        } else {
+                            x++;
+                        }
+                    }
+                }
+            }
+        }
+        """
+    with slither_from_source(source) as slither:
+        c: Contract = slither.get_contract_from_name("Contract")[0]
+        f: Function = c.functions[0]
+        node_if = f.nodes[2]
+        assert node_if.son_true.type == NodeType.RETURN
+        node_explicit = node_if.son_true
+        assert isinstance(node_explicit.irs[0], Return)
+        assert node_explicit.irs[0].values[0] == f.get_local_variable_from_name("a")
+        node_end_if = f.nodes[16]
+        assert node_end_if.type == NodeType.ENDIF
+        assert node_end_if.sons[0].type == NodeType.RETURN
+        node_implicit = node_end_if.sons[0]
+        assert isinstance(node_implicit.irs[0], Return)
+        assert node_implicit.irs[0].values[0] == f.get_local_variable_from_name("x")
+        node_throw = f.nodes[11]
+        assert node_throw.type == NodeType.THROW
+        assert len(node_throw.sons) == 0
+
+
 def test_issue_1846_ternary_in_ternary(slither_from_source):
     source = """
         contract Contract {