- **f-vdiff**/dibu: port the DELETE/INSERT collapsing from [](8752aca1b7187d39) into the ncurses unified diff view.


# Maybe (and Maybe Not) TODO

- **Undo** support.

- **BOMs**. Fossil's diff APIs internally convert their inputs to UTF8 and strip the BOM (if any) from them. libf does not do that. On the one hand i'm hesitant to do so because these blobs can be anything at all (not necessarily SCM controlled). On other other, for annotate's sake it might make sense to do so automatically because the user is passing in artifact IDs instead of file content. On the other other hand, the fossil routine for doing that (blob_to_utf8_no_bom()) is far, far more involved that simply stripping a BOM. i'm torn on whether that's the library's job or not, and really dislike having to either mutate the original inputs or reallocate them to make that conversion. OTOH, fossil does so.
- **BOMs**. Fossil's diff APIs internally convert their inputs to UTF8 and strip the BOM (if any) from them. libf does not do that. On the one hand i'm hesitant to do so because these blobs can be anything at all (not necessarily SCM controlled). On the other hand, for annotate's sake it might make sense to do so automatically because the user is passing in artifact IDs instead of file content. On the other other hand, the fossil routine for doing that (blob_to_utf8_no_bom()) is far, far more involved that simply stripping a BOM. i'm torn on whether that's the library's job or not, and really dislike having to either mutate the original inputs or reallocate them to make that conversion. OTOH, fossil does so.

- **Symlinks**. i have always strongly disagreed with the addition of symlink support into fossil: platform-specific constructs simply have no place in the core of any SCM (with the "effectively necessary," as well as unobtrusive, exception of the executable bit). For platforms which don't support symlinks, fossil stores/manages them as plain text files with a single line holding the name of the referenced file. This is *very likely* the only route the library will take to supporting symlinks, especially since the hassles symlink handling caused fossil in late 2020 (long story). Probably the only way the library will support proper symlinks is if someone who uses that feature adds and maintains it.

- **Backlinks**. Crosslinking "should" update the internal list of backlinks from certain text fields, but doing so requires parsing wiki/markdown-format text. See [`backlink.c` in the fossil tree](https://fossil-scm.org/home/file?name=src/backlink.c&ci=trunk) for the details. On the other hand, backlinks support only requires parsing wiki links, not the full grammar, so it might not be as painful as it initially sounds... though somewhat more for markdown, where we're required to do a multi-pass scan to handle its linking model. (We'd also need to handle verbatim blocks to avoid parsing links inside those blocks.)

- **Ticket support**. Ticket handling is surprisingly complicated, due largely to the customizability of the ticket database schema. If fossil-compatible ticket supports gets added to libfossil, it will very likely be because someone other than myself adds it! The core artifact data structure supports tickets, so the bits required for adding it are in place. Fossil, however, also uses the TH1 scripting engine in its ticket handling and that's an aspect the library-level API should arguably avoid.