Improve function lookup for bytes (#1163)

* Improve function lookup for bytes

* Update dapp test

* black

scripts/ci_test_dapp.sh

@@ -18,7 +18,7 @@ dapp init
 slither . --detect external-function
 
 # TODO: make more elaborate test
-if [ $? -eq 3 ]
+if [ $? -eq 4 ]
 then
     exit 0
 fi

slither/slithir/convert.py

@@ -196,7 +196,7 @@ def _fits_under_byte(val: Union[int, str]) -> List[str]:
         return [f"bytes{size}"]
     # val is a str
     length = len(val.encode("utf-8"))
-    return [f"bytes{f}" for f in range(length, 33)]
+    return [f"bytes{f}" for f in range(length, 33)] + ["bytes"]
 
 
 def _find_function_from_parameter(ir: Call, candidates: List[Function]) -> Optional[Function]:

tests/ast-parsing/bytes_call.sol

@@ -0,0 +1,17 @@
+contract Log{
+    // Check that we can parse string/bytes
+    function f(bytes calldata) external{
+    }
+
+    function f(bytes4) external{
+    }
+}
+
+contract A{
+
+    Log l;
+    function test() internal{
+        l.f("TESTA");
+    }
+}
+

tests/ast-parsing/expected/bytes_call.sol-0.8.12-compact.json

@@ -0,0 +1,9 @@
+{
+  "Log": {
+    "f(bytes)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n}\n",
+    "f(bytes4)": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n}\n"
+  },
+  "A": {
+    "test()": "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

@@ -403,6 +403,7 @@ def make_version(minor: int, patch_min: int, patch_max: int) -> List[str]:
     Test("complex_imports/import_aliases/test.sol", VERSIONS_08),
     # 0.8.9 crashes on our testcase
     Test("user_defined_types.sol", ["0.8.8"] + make_version(8, 10, 12)),
+    Test("bytes_call.sol", ["0.8.12"]),
 ]
 # create the output folder if needed
 try: