feat(lsp): add 'above' codelens position and setup config

lua/lsp/codelens.lua

@@ -6,9 +6,11 @@ local REFRESH_DEBOUNCE_MS = 200
 
 local M = {}
 
----@type "eol" | "right_align" | "inline"
-M.virt_text_pos = "eol"
-M.separator = " | "
+---@alias ow.lsp.codelens.Position "eol" | "right_align" | "inline" | "above"
+
+---@type ow.lsp.codelens.Position
+local position = "above"
+local separator = " | "
 
 ---@type table<integer, ow.lsp.codelens.State>
 local state_by_buf = {}
@@ -69,12 +71,38 @@ function Row:render(buf)
     for i, lens in ipairs(self.ready) do
         table.insert(parts, { lens.command.title, "LspCodeLens" })
         if i < #self.ready then
-            table.insert(parts, { M.separator, "LspCodeLensSeparator" })
+            table.insert(parts, { separator, "LspCodeLensSeparator" })
         end
     end
-    local col = M.virt_text_pos == "inline"
-            and self.ready[1].range.start.character
-        or 0
+
+    local col, opts
+    if position == "above" then
+        local line = vim.api.nvim_buf_get_lines(
+            buf,
+            self.row,
+            self.row + 1,
+            false
+        )[1] or ""
+        local indent = line:match("^%s*") or ""
+        local chunks = parts
+        if indent ~= "" then
+            chunks = { { indent, "LspCodeLensSeparator" } }
+            vim.list_extend(chunks, parts)
+        end
+        col = 0
+        opts = {
+            virt_lines = { chunks },
+            virt_lines_above = true,
+            hl_mode = "combine",
+        }
+    else
+        col = position == "inline" and self.ready[1].range.start.character or 0
+        opts = {
+            virt_text = parts,
+            virt_text_pos = position,
+            hl_mode = "combine",
+        }
+    end
 
     -- One extmark per row. Extmarks auto-shift with edits, so multiple from
     -- prior refreshes can end up on the same row; pick the first and drop
@@ -95,22 +123,21 @@ function Row:render(buf)
         end
     end
 
-    if
-        primary
-        and primary.col == col
-        and primary.details
-        and primary.details.virt_text_pos == M.virt_text_pos
-        and vim.deep_equal(primary.details.virt_text, parts)
-    then
-        return
+    if primary and primary.col == col and primary.details then
+        local d = primary.details --[[@as vim.api.keyset.extmark_details]]
+        local same = opts.virt_lines
+                and vim.deep_equal(d.virt_lines, opts.virt_lines)
+                and d.virt_lines_above == opts.virt_lines_above
+            or not opts.virt_lines
+                and d.virt_text_pos == opts.virt_text_pos
+                and vim.deep_equal(d.virt_text, opts.virt_text)
+        if same then
+            return
+        end
     end
 
-    vim.api.nvim_buf_set_extmark(buf, NS, self.row, col, {
-        id = primary and primary.id or nil,
-        virt_text = parts,
-        virt_text_pos = M.virt_text_pos,
-        hl_mode = "combine",
-    })
+    opts.id = primary and primary.id or nil
+    vim.api.nvim_buf_set_extmark(buf, NS, self.row, col, opts)
 end
 
 ---@class ow.lsp.codelens.State
@@ -292,7 +319,20 @@ function M.toggle(buf)
     get_state(buf):toggle()
 end
 
-function M.setup()
+---@class ow.lsp.codelens.SetupOpts
+---@field position? ow.lsp.codelens.Position
+---@field separator? string
+
+---@param opts? ow.lsp.codelens.SetupOpts
+function M.setup(opts)
+    opts = opts or {}
+    if opts.position ~= nil then
+        position = opts.position
+    end
+    if opts.separator ~= nil then
+        separator = opts.separator
+    end
+
     vim.api.nvim_create_autocmd({ "BufEnter", "LspAttach" }, {
         group = GROUP,
         callback = function(ev)