refact: use Python's Enum for KIND

Author: boriel

src/api/constants.py

@@ -197,31 +197,24 @@ def to_string(scope: 'SCOPE'):
         return scope.value
 
 
-class KIND:
+@enum.unique
+class KIND(str, enum.Enum):
     """ Enum kind
     """
-    unknown = None
+    unknown = 'unknown'
     var = 'var'
     function = 'function'
     sub = 'sub'
-    type_ = 'type'
-
-    _NAMES = {
-        unknown: '(unknown)',
-        var: 'variable',
-        function: 'function',
-        sub: 'subroutine',
-        type_: 'type'
-    }
+    type = 'type'
 
-    @classmethod
-    def is_valid(cls, kind):
-        return cls._NAMES.get(kind, None) is not None
+    @staticmethod
+    def is_valid(kind: Union[str, 'KIND']):
+        return kind in set(KIND)
 
-    @classmethod
-    def to_string(cls, kind):
-        assert cls.is_valid(kind)
-        return cls._NAMES.get(kind)
+    @staticmethod
+    def to_string(kind: 'KIND'):
+        assert KIND.is_valid(kind)
+        return kind.value
 
 
 class CONVENTION:

src/api/errmsg.py

@@ -270,7 +270,7 @@ def syntax_error_cant_convert_to_type(lineno: int, expr_str: str, type_: str):
 # Syntax error: is a SUB not a FUNCTION
 # ----------------------------------------
 def syntax_error_is_a_sub_not_a_func(lineno: int, name: str):
-    error(lineno, "'%s' is SUBROUTINE not a FUNCTION" % name)
+    error(lineno, "'%s' is a SUB not a FUNCTION" % name)
 
 
 # ----------------------------------------

tests/functional/test_errmsg.txt

@@ -15,9 +15,9 @@ doloop2.bas:4: warning: Variable 'a' is never used
 dowhile1.bas:1: warning: Condition is always True
 dowhile1.bas:1: warning: Empty loop
 >>> process_file('subcall1.bas')
-subcall1.bas:6: error: 'test' is SUBROUTINE not a FUNCTION
+subcall1.bas:6: error: 'test' is a SUB not a FUNCTION
 >>> process_file('subcall2.bas')
-subcall2.bas:6: error: 'test' is a SUBROUTINE, not a FUNCTION
+subcall2.bas:6: error: 'test' is a SUB, not a FUNCTION
 >>> process_file('prepro05.bi')
 prepro05.bi:2: warning: [W510] "test" redefined (previous definition at prepro05.bi:2)
 >>> process_file('prepro07.bi')
@@ -86,7 +86,7 @@ strict.bas:4: error: strict mode: missing type declaration for 'a'
 >>> process_file('errletfunc.bas')
 errletfunc.bas:5: error: Cannot assign a value to 'x'. It's not a variable
 >>> process_file('read0.bas')
-read0.bas:12: error: 'x' is SUBROUTINE not a FUNCTION
+read0.bas:12: error: 'x' is a SUB not a FUNCTION
 >>> process_file('read1.bas')
 read1.bas:11: error: Cannot read 'x'. It's an array
 >>> process_file('read3.bas')