add support for char constants

Author: andreax79

README.md

@@ -129,6 +129,8 @@ Different enum styles are supported in struct/union definitions.
 enum Type_A a;  // externally defined using CEnum
 enum Type_B {A, B, C} b;
 enum {A, B, C} c;
+enum Type_D : short {A, B, C} d; // specify the underlying type
+enum Direction { left = 'l', right = 'r' };
 ```
 
 ### Nested structs/unions
@@ -334,3 +336,6 @@ Output example:
 000001f0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 55 aa  |..............U.|
 ```
 
+Links
+-----
+* [C/C++ reference](https://en.cppreference.com/)

cstruct/c_expr.py

@@ -58,6 +58,8 @@ def c_eval(expr: str) -> Union[int, float]:
     try:
         expr = expr.replace("!", " not ").replace("&&", " and ").replace("||", " or ")
         return eval_node(ast.parse(expr.strip()).body[0])
+    except EvalError:
+        raise
     except Exception:
         raise EvalError
 
@@ -67,6 +69,11 @@ def eval_node(node: ast.stmt) -> Union[int, float]:
     result = handler(node)
     if isinstance(result, bool):  # convert bool to int
         return 1 if result else 0
+    elif isinstance(result, str):  # convert char to int
+        if len(result) != 1:
+            raise EvalError("Multi-character constant")
+        else:
+            return ord(result)
     return result
 
 

tests/test_c_expr.py

@@ -78,3 +78,8 @@ def test_c_expr_compare():
     assert c_eval("3 <= 30") == 1
     define("A10", 10)
     assert c_eval("((A10 < 6) || (A10>10))") == 0
+
+
+def test_c_expr_char():
+    assert c_eval("'A'") == 65
+    assert c_eval("'B'") == 66

tests/test_cenum.py

@@ -104,3 +104,9 @@ def test_type():
     color = cstruct.parse("enum Color : unsigned short { red, green, blue };")
     assert color.__size__ == 2
     assert cstruct.sizeof("enum Color") == 2
+
+
+def test_char():
+    direction = cstruct.parse("enum Direction { left = 'l', right = 'r' };")
+    assert direction.__size__ == 4
+    assert cstruct.sizeof("enum Direction") == 4