Parsing a + b to hold_keys(a, b) (#392)

inputremapper/injection/macros/parse.py

@@ -328,28 +328,20 @@ def _parse_recurse(code, context, macro_instance=None, depth=0):
 
 
 def handle_plus_syntax(macro):
-    """transform a + b + c to modify(a,modify(b,modify(c,hold())))"""
+    """transform a + b + c to hold_keys(a,b,c)"""
     if "+" not in macro:
         return macro
 
     if "(" in macro or ")" in macro:
-        raise ValueError(
-            f'Mixing "+" and macros is unsupported: "{ macro}"'
-        )  # TODO: MacroParsingError
+        # TODO: MacroParsingError
+        raise ValueError(f'Mixing "+" and macros is unsupported: "{ macro}"')
 
     chunks = [chunk.strip() for chunk in macro.split("+")]
-    output = ""
-    depth = 0
-    for chunk in chunks:
-        if chunk == "":
-            # invalid syntax
-            raise ValueError(f'Invalid syntax for "{macro}"')
-
-        depth += 1
-        output += f"modify({chunk},"
-
-    output += "hold()"
-    output += depth * ")"
+
+    if "" in chunks:
+        raise ValueError(f'Invalid syntax for "{macro}"')
+
+    output = f"hold_keys({','.join(chunks)})"
 
     logger.debug('Transformed "%s" to "%s"', macro, output)
     return output

tests/unit/test_macros.py

@@ -266,16 +266,13 @@ def test_is_this_a_macro(self):
         self.assertTrue(is_this_a_macro("a + b + c"))
 
     def test_handle_plus_syntax(self):
-        self.assertEqual(handle_plus_syntax("a + b"), "modify(a,modify(b,hold()))")
-        self.assertEqual(
-            handle_plus_syntax("a + b + c"), "modify(a,modify(b,modify(c,hold())))"
-        )
-        self.assertEqual(
-            handle_plus_syntax(" a+b+c "), "modify(a,modify(b,modify(c,hold())))"
-        )
+        self.assertEqual(handle_plus_syntax("a + b"), "hold_keys(a,b)")
+        self.assertEqual(handle_plus_syntax("a + b + c"), "hold_keys(a,b,c)")
+        self.assertEqual(handle_plus_syntax(" a+b+c "), "hold_keys(a,b,c)")
 
-        # invalid
-        strings = ["+", "a+", "+b", "key(a + b)"]
+        # invalid. The last one with `key` should not have been a parameter
+        # of this function to begin with.
+        strings = ["+", "a+", "+b", "a\n+\n+\nb", "key(a + b)"]
         for string in strings:
             with self.assertRaises(ValueError):
                 logger.info(f'testing "%s"', string)
@@ -287,7 +284,7 @@ def test_handle_plus_syntax(self):
 
     def test_parse_plus_syntax(self):
         macro = parse("a + b")
-        self.assertEqual(macro.code, "modify(a,modify(b,hold()))")
+        self.assertEqual(macro.code, "hold_keys(a,b)")
 
         # this is not erroneously recognized as "plus" syntax
         macro = parse("key(a) # a + b")