remove empty entries and do not report them as found

paper/bib.py

@@ -235,10 +235,15 @@ def generate_entry(block):
                         output += '  {:15}= {},\n'.format(s,'{}')
                 else:
                     c = block['sections'].pop(idx)[1]
-                    diagnostic(Green('field found:'.ljust(17)) + s.ljust(13) + c)
-                    if s == 'author':
-                        c = authors(c)
-                    output += '  {:15}= {},\n'.format(s,c)
+                    if c == '' or c == '{}':
+                        diagnostic(Red('field not found:'.ljust(17)) + s)
+                        if i != 1 or config['extend']:
+                            output += '  {:15}= {},\n'.format(s,'{}')
+                    else:
+                        diagnostic(Green('field found:'.ljust(17)) + s.ljust(13) + c)
+                        if s == 'author':
+                            c = authors(c)
+                        output += '  {:15}= {},\n'.format(s,c)
 
         if len(block['sections']) > 0:
             block['sections'].sort(key=lambda a : a[0])

paper/collection.bib

@@ -78,6 +78,7 @@
 
 @book{Abrial:1996:BAP:236705,
   author         = {Jean-Raymond Abrial},
+  editor         = {},
   title          = {The B-book: Assigning Programs to Meanings},
   publisher      = {Cambridge University Press},
   year           = {1996},
@@ -386,7 +387,6 @@
 
 @misc{coq-faq,
 
-  author         = {},
   title          = {{The Coq Proof Assistant} -- {Frequently Asked Questions}},
   note           = {\url{https://coq.inria.fr/faq}},
 }
@@ -462,7 +462,6 @@
 
 @misc{things-that-use-curve25519,
 
-  author         = {},
   title          = {Things that use Curve25519},
   note           = {\url{https://ianix.com/pub/curve25519-deployment.html}},