tests: Do not let LibreOffice hang on the large test set

Some of the files in our large test set can make LibreOffice hang. We
do not have a proper solution for this yet, but we can at least make
the tests timeout quickly, so that they can finish at some point.

Refs #878

tests/test_large_set.py

@@ -75,7 +75,12 @@ def run_doc_test(self, doc: Path, tmp_path: Path) -> None:
             stdout=subprocess.PIPE,
             stderr=subprocess.STDOUT,
         )
-        out, _ = p.communicate()
+        try:
+            # Set a global timeout of 30 minutes for the processing of a document.
+            # This is necessary due to https://github.com/freedomofpress/dangerzone/issues/878
+            out, _ = p.communicate(timeout=30 * 60)
+        except subprocess.TimeoutExpired:
+            print(f"*** TIMEOUT EXCEEDED FOR DOCUMENT '{doc}' ***")
         from strip_ansi import strip_ansi
 
         print(strip_ansi(out.decode()))