diff --git a/tools/generation/lib/template.py b/tools/generation/lib/template.py
index d5fc78d8462a4eb6f9544fc3e879b0adf6dd6c7c..c0a12ccf0253f9ef95a846fd5a4606e134b56024 100644
--- a/tools/generation/lib/template.py
+++ b/tools/generation/lib/template.py
@@ -160,14 +160,14 @@ class Template:
         flags += case_values['meta'].get('flags', [])
         flags += self.attribs['meta'].get('flags', [])
         flags = list(OrderedDict.fromkeys(flags))
-        lines += ['flags: ' + yaml.dump(flags).strip()]
+        lines += ['flags: ' + re.sub('\n\s*', ' ', yaml.dump(flags).strip())]
 
         includes = []
         includes += case_values['meta'].get('includes', [])
         includes += self.attribs['meta'].get('includes', [])
         includes = list(OrderedDict.fromkeys(includes))
         if len(includes):
-            lines += ['includes: ' + yaml.dump(includes).strip()]
+            lines += ['includes: ' + re.sub('\n\s*', ' ', yaml.dump(includes).strip())]
 
         if case_values['meta'].get('negative'):
             if self.attribs['meta'].get('negative'):