Improve assignment of sections and tags

This allows to assign an existing instance, which comes handy for
example when assigning a sliced Section.

Signed-off-by: Nikola Forró <[email protected]>

Author: nforro

specfile/sections.py

@@ -143,7 +143,10 @@ def __setattr__(self, name: str, value: List[str]) -> None:
         if name.split()[0].lower() not in SECTION_NAMES:
             return super().__setattr__(name, value)
         try:
-            self.data[self.find(name)].data = value
+            if isinstance(value, Section):
+                self.data[self.find(name)] = value
+            else:
+                self.data[self.find(name)].data = value
         except ValueError:
             raise AttributeError(name)
 

specfile/tags.py

@@ -577,7 +577,10 @@ def __setattr__(self, name: str, value: str) -> None:
         if name.capitalize().rstrip("0123456789") not in TAG_NAMES:
             return super().__setattr__(name, value)
         try:
-            self.data[self.find(name)].value = value
+            if isinstance(value, Tag):
+                self.data[self.find(name)] = value
+            else:
+                self.data[self.find(name)].value = value
         except ValueError:
             raise AttributeError(name)