UBUNTU: [Packaging] annotations: Check validity of FLAVOUR_DEP

FLAVOUR_DEP is used to map flavors from the main annotations file to
flavors from includes. Currently, there is no check that any of the
listed flavors exists or is valid so the resulting behavior is
(probably) undefined/unexpected. Add a sanity check to verify the
FLAVOUR_DEP flavors.

Signed-off-by: Juerg Haefliger <juerg.haefliger@canonical.com>
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>

debian/scripts/misc/kconfig/annotations.py

@@ -57,8 +57,17 @@ class Annotation(Config):
             line = re.sub(r' +', ' ', line)
             line = line.strip()
 
-            # Ignore empty lines and comments
-            if not line or line.startswith('#'):
+            # Ignore empty lines
+            if not line:
+                continue
+
+            # Catpure flavors of included files
+            if line.startswith('# FLAVOUR: '):
+                self.include_flavour += line.split(' ')[2:]
+                continue
+
+            # Ignore comments
+            if line.startswith('#'):
                 continue
 
             # Handle includes (recursively)
@@ -112,6 +121,7 @@ class Annotation(Config):
         self.flavour_dep = {}
         self.include = []
         self.header = ''
+        self.include_flavour = []
 
         # Parse header (only main header will considered, headers in includes
         # will be treated as comments)
@@ -133,6 +143,13 @@ class Annotation(Config):
         # Parse body (handle includes recursively)
         self._parse_body(data)
 
+        # Sanity check: Verify that all FLAVOUR_DEP flavors are valid
+        for src, tgt in self.flavour_dep.items():
+            if src not in self.flavour:
+                raise Exception(f'Invalid source flavour in FLAVOUR_DEP: {src}')
+            if tgt not in self.include_flavour:
+                raise Exception(f'Invalid target flavour in FLAVOUR_DEP: {tgt}')
+
     def _remove_entry(self, config: str):
         if self.config[config]:
             del self.config[config]