fix: Correctly update unmodified stage buffers when index changes

(fixes #280)

Author: sindrets

lua/diffview/scene/file_entry.lua

@@ -137,26 +137,31 @@ function FileEntry:validate_stage_buffers(adapter, stat)
     if not cached_stat or cached_stat.mtime < stat.mtime.sec then
       for _, f in ipairs(self.layout:files()) do
         if f.rev.type == RevType.STAGE and f:is_valid() then
-          if f.rev.stage == 0 then
+          if f.rev.stage > 0 then
+            -- We only care about stage 0 here
+            f:dispose_buffer()
+          else
             local is_modified = vim.bo[f.bufnr].modified
 
             if f.blob_hash then
               local new_hash = f.adapter:file_blob_hash(f.path)
-              if new_hash and new_hash ~= f.blob_hash and is_modified then
-                utils.warn((
-                  "A file was changed in the index since you started editing it!"
-                  .. " Be careful not to lose any staged changes when writing to this buffer: %s"
-                ):format(api.nvim_buf_get_name(f.bufnr)))
+
+              if new_hash and new_hash ~= f.blob_hash then
+                if is_modified then
+                  utils.warn((
+                    "A file was changed in the index since you started editing it!"
+                    .. " Be careful not to lose any staged changes when writing to this buffer: %s"
+                  ):format(api.nvim_buf_get_name(f.bufnr)))
+                else
+                  f:dispose_buffer()
+                end
               end
             elseif not is_modified then
               -- Should be very rare that we don't have an index-buffer's blob
               -- hash. But in that case, we can't warn the user when a file
               -- changes in the index while they're editing its index buffer.
               f:dispose_buffer()
             end
-
-          else
-            f:dispose_buffer()
           end
         end
       end

lua/diffview/vcs/adapters/git/init.lua

@@ -1081,11 +1081,12 @@ function GitAdapter:file_blob_hash(path, rev_arg)
     "rev-parse",
     "--revs-only",
     ("%s:%s"):format(rev_arg or "", path)
-  }, self.ctx.toplevel)
+  }, {
+    cwd = self.ctx.toplevel,
+    retry_on_empty = 2,
+  })
 
-  if code ~= 0 then
-    return
-  end
+  if code ~= 0 then return end
 
   return vim.trim(out[1])
 end