feat(blame): show commit's hunk in the line popup

lua/git/core/popup.lua

@@ -0,0 +1,82 @@
+local M = {}
+
+---@param win integer
+---@return boolean
+local function has_border(win)
+    local b = vim.api.nvim_win_get_config(win).border
+    if not b or b == "none" or b == "" then
+        return false
+    end
+    if type(b) == "table" and #b == 0 then
+        return false
+    end
+    return true
+end
+
+---@param lines string[]
+---@param opts? { min_width?: integer, padding?: integer }
+---@return integer width
+---@return integer height
+function M.size_for(lines, opts)
+    opts = opts or {}
+    local width = 1
+    for _, l in ipairs(lines) do
+        local w = vim.api.nvim_strwidth(l)
+        if w > width then
+            width = w
+        end
+    end
+    width = math.min(
+        math.max(width + (opts.padding or 1), opts.min_width or 30),
+        100,
+        vim.o.columns - 4
+    )
+    local height =
+        math.min(math.max(#lines, 1), 20, math.floor(vim.o.lines / 2))
+    return width, height
+end
+
+---@param pbuf integer
+---@param win integer
+---@param ns integer
+function M.paint_overflow(pbuf, win, ns)
+    vim.schedule(function()
+        if
+            not vim.api.nvim_buf_is_valid(pbuf)
+            or not vim.api.nvim_win_is_valid(win)
+        then
+            return
+        end
+        vim.api.nvim_buf_clear_namespace(pbuf, ns, 0, -1)
+        local total = vim.api.nvim_buf_line_count(pbuf)
+        local top, bottom = unpack(vim.api.nvim_win_call(win, function()
+            return { vim.fn.line("w0"), vim.fn.line("w$") }
+        end)) ---@cast top integer
+        ---@cast bottom integer
+        local needs_top = top > 1
+        local needs_bottom = bottom < total
+        if has_border(win) then
+            pcall(vim.api.nvim_win_set_config, win, {
+                title = needs_top and { { "▲ ", "FloatBorder" } } or "",
+                title_pos = needs_top and "right" or nil,
+                footer = needs_bottom and { { "▼ ", "FloatBorder" } } or "",
+                footer_pos = needs_bottom and "right" or nil,
+            })
+            return
+        end
+        if needs_top then
+            pcall(vim.api.nvim_buf_set_extmark, pbuf, ns, top - 1, 0, {
+                virt_text = { { "▲ ", "GitPopupEnd" } },
+                virt_text_pos = "right_align",
+            })
+        end
+        if needs_bottom then
+            pcall(vim.api.nvim_buf_set_extmark, pbuf, ns, bottom - 1, 0, {
+                virt_text = { { "▼ ", "GitPopupEnd" } },
+                virt_text_pos = "right_align",
+            })
+        end
+    end)
+end
+
+return M

lua/git/core/util.lua

@@ -120,6 +120,34 @@ function M.split_lines(content)
     return lines
 end
 
+---@param buf integer
+---@param ns integer
+---@param lines string[]
+---@param start_row integer  0-indexed row of the first line in `lines`
+function M.paint_diff_lines(buf, ns, lines, start_row)
+    for i, line in ipairs(lines) do
+        local hl ---@type string?
+        local prefix = line:sub(1, 1)
+        if prefix == "+" then
+            hl = "GitHunkAdded"
+        elseif prefix == "-" then
+            hl = "GitHunkRemoved"
+        elseif vim.startswith(line, "@@") then
+            hl = "GitHunkHeader"
+        end
+        if hl then
+            pcall(
+                vim.api.nvim_buf_set_extmark,
+                buf,
+                ns,
+                start_row + i - 1,
+                0,
+                { line_hl_group = hl }
+            )
+        end
+    end
+end
+
 ---@class ow.Git.Util.DebounceHandle
 ---@field cancel fun()
 ---@field flush fun()