extmarks/bufhl: reimplement using new marktree data structure

Add new "splice" interface for tracking buffer changes at the byte
level. This will later be reused for byte-resolution buffer updates.
(Implementation has been started, but using undocumented "_on_bytes"
option now as interface hasn't been finalized).

Use this interface to improve many edge cases of extmark adjustment.
Changed tests indicate previously incorrect behavior. Adding tests for
more edge cases will be follow-up work (overlaps on_bytes tests)

Don't consider creation/deletion of marks an undoable event by itself.
This behavior was never documented, and imposes  complexity for little gain.

Add nvim__buf_add_decoration temporary API for direct access to the new
implementation. This should be refactored into a proper API for
decorations, probably involving a huge dict.

fixes #11598

1 files changed, 13 insertions, 1 deletions

diff --git a/src/nvim/map.h b/src/nvim/map.h
index fec91ac0c2..761938776d 100644
--- a/src/nvim/map.h
+++ b/src/nvim/map.h
@@ -4,9 +4,9 @@
 #include <stdbool.h>
 
 #include "nvim/map_defs.h"
+#include "nvim/mark_extended_defs.h"
 #include "nvim/api/private/defs.h"
 #include "nvim/api/private/dispatch.h"
-#include "nvim/bufhl_defs.h"
 #include "nvim/highlight_defs.h"
 
 #if defined(__NetBSD__)
@@ -38,6 +38,18 @@ MAP_DECLS(int, int)
 MAP_DECLS(cstr_t, ptr_t)
 MAP_DECLS(ptr_t, ptr_t)
 MAP_DECLS(uint64_t, ptr_t)
+MAP_DECLS(uint64_t, ssize_t)
+MAP_DECLS(uint64_t, uint64_t)
+
+// NB: this is the only way to define a struct both containing and contained
+// in a map...
+typedef struct ExtmarkNs {  // For namespacing extmarks
+  Map(uint64_t, uint64_t) *map;  // For fast lookup
+  uint64_t free_id;         // For automatically assigning id's
+} ExtmarkNs;
+
+MAP_DECLS(uint64_t, ExtmarkNs)
+MAP_DECLS(uint64_t, ExtmarkItem)
 MAP_DECLS(handle_T, ptr_t)
 MAP_DECLS(String, MsgpackRpcRequestHandler)
 MAP_DECLS(HlEntry, int)