This reproduces the symptoms of bug report
id:
20150422065630.6330.90536@hoothoot
--- /dev/null
+#!/usr/bin/env bash
+test_description="parsing of bad dates"
+. ./test-lib.sh || exit 1
+
+add_message [date]='"()"'
+
+test_begin_subtest 'Bad dates translate to a date after the Unix epoch'
+test_subtest_known_broken
+cat <<EOF >EXPECTED
+thread:0000000000000001 1970-01-01 [1/1] Notmuch Test Suite; Test message #1 (inbox unread)
+EOF
+notmuch search '*' > OUTPUT
+test_expect_equal_file EXPECTED OUTPUT
+
+test_done