removes comments from lambda (#998)

* removes comments from lambda

* include comments in lambda test

* pylint no else return

esphome/core.py

@@ -230,10 +230,23 @@ class Lambda:
         self._parts = None
         self._requires_ids = None
 
+    # https://stackoverflow.com/a/241506/229052
+    def comment_remover(self, text):
+        def replacer(match):
+            s = match.group(0)
+            if s.startswith('/'):
+                return " "  # note: a space and not an empty string
+            return s
+        pattern = re.compile(
+            r'//.*?$|/\*.*?\*/|\'(?:\\.|[^\\\'])*\'|"(?:\\.|[^\\"])*"',
+            re.DOTALL | re.MULTILINE
+        )
+        return re.sub(pattern, replacer, text)
+
     @property
     def parts(self):
         if self._parts is None:
-            self._parts = re.split(LAMBDA_PROG, self._value)
+            self._parts = re.split(LAMBDA_PROG, self.comment_remover(self._value))
         return self._parts
 
     @property

tests/unit_tests/test_core.py

@@ -211,6 +211,10 @@ class TestTimePeriod:
 SAMPLE_LAMBDA = """
 it.strftime(64, 0, id(my_font), TextAlign::TOP_CENTER, "%H:%M:%S", id(esptime).now());
 it.printf(64, 16, id(my_font2), TextAlign::TOP_CENTER, "%.1f°C (%.1f%%)", id( office_tmp ).state, id(office_hmd).state);
+//id(my_commented_id)
+int x = 4;/* id(my_commented_id2)
+id(my_commented_id3)
+*/
 """
 
 
@@ -246,7 +250,7 @@ class TestLambda:
             "state, ",
             "office_hmd",
             ".",
-            "state);"
+            "state);\n \nint x = 4; "
         ]
 
     def test_requires_ids(self):