Parser: Assertion failed: buffer->have_positions == source->have_positions || !buffer->len || !source->len), function hb_buffer_append, file hb-buffer.cc, line 2036

[marcoroth]

Reported by @miharekar

just tried 0.8.2 and it crashes my rails server instantly

[f3113fc1-ece5-4311-8c33-88e544483232] [::1]   Roaster Load (0.8ms)  SELECT "roasters".* FROM "roasters" WHERE "roasters"."id" IN ('8bd14c50-217d-422f-be44-2434cc258d9a', '9d6f731a-3312-4b49-98f4-2581bd35930b', 'e05a1278-aab4-49e8-b9a3-d7a0951b48bb', '41b933f2-a932-4588-abc4-e59b565db154', 'e7c11557-af97-4174-b744-5b5837380c4e', '60bab676-5929-41d2-801b-f49541a163c7') /*action='index',application='Visualizer',controller='shots'*/
[f3113fc1-ece5-4311-8c33-88e544483232] [::1]   ↳ app/controllers/concerns/cursor_paginatable.rb:4:in 'CursorPaginatable#paginate_with_cursor'
[f3113fc1-ece5-4311-8c33-88e544483232] [::1]   Rendering layout layouts/application.html.erb
[f3113fc1-ece5-4311-8c33-88e544483232] [::1]   Rendering shots/index.html.erb within layouts/application
Assertion failed: (buffer->have_positions == source->have_positions || !buffer->len || !source->len), function hb_buffer_append, file hb-buffer.cc, line 2036.
zsh: abort      rails s

Looks like our hb_buffer_append gets shadowed by libharfbuzz:
https://github.com/harfbuzz/harfbuzz/blob/3129b36c04a35428e5350945861d04e3697d2bf9/src/hb-buffer.cc#L2029 in this case 🤔

Similar case to #534

[marcoroth]

Resolved via #906