turns out gitsigns is actually very useful

lua/conf/plugins/gitsigns.lua

@@ -0,0 +1,85 @@
+local map = core.misc.map
+
+return { "lewis6991/gitsigns.nvim",
+  lazy = function(load)
+    load:auto({ "BufEnter", "BufNew" }, {
+      callback = function()
+        local paths = vim.fs.find({ ".git", }, { upward = true })
+        if #paths > 0 then
+          load:cleanup()
+        end
+      end
+    })
+    load:cmd("Gitsigns")
+  end,
+  load = function()
+    local gs = require("gitsigns")
+
+    gs.setup {
+      signs = {
+        add          = { text = "│" },
+        change       = { text = "│" },
+        delete       = { text = "-" },
+        topdelete    = { text = "‾" },
+        changedelete = { text = "~" },
+        untracked    = { text = "┆" }
+      },
+
+      signcolumn = true,
+      numhl      = false,
+      linehl     = false,
+      word_diff  = false,
+
+      watch_gitdir = {
+        interval = 1000,
+        follow_files = true
+      },
+
+      attach_to_untracked = true,
+      current_line_blame_formatter = "<author>, <author_time:%Y-%m-%d> - <summary>",
+
+      preview_config = { border = vim.g.border_style },
+
+      on_attach = function(bufnr)
+        local opts = { buffer = bufnr }
+
+        -- Navigation
+        map("n", "]c", function()
+          if vim.wo.diff then
+            return "]c"
+          end
+          vim.schedule(function() gs.next_hunk() end)
+        end, { expr = true, buffer = bufnr })
+
+        map("n", "[c", function()
+          if vim.wo.diff then
+            return "[c"
+          end
+          vim.schedule(function() gs.prev_hunk() end)
+        end, { expr = true, buffer = bufnr })
+
+        -- Actions
+        map("n", "<leader>hs", gs.stage_hunk, opts)
+        map("n", "<leader>hr", gs.reset_hunk, opts)
+        map("v", "<leader>hs", function()
+          gs.stage_hunk { vim.fn.line("."), vim.fn.line("v") }
+        end, opts)
+        map("v", "<leader>hr", function()
+          gs.reset_hunk { vim.fn.line("."), vim.fn.line("v") }
+        end, opts)
+        map("n", "<leader>hS", gs.stage_buffer, opts)
+        map("n", "<leader>hu", gs.undo_stage_hunk, opts)
+        map("n", "<leader>hR", gs.reset_buffer, opts)
+        map("n", "<leader>hp", gs.preview_hunk, opts)
+        map("n", "<leader>hb", function() gs.blame_line { full = true } end, opts)
+        map("n", "<leader>tb", gs.toggle_current_line_blame, opts)
+        map("n", "<leader>hd", gs.diffthis, opts)
+        map("n", "<leader>hD", function() gs.diffthis("~") end, opts)
+        map("n", "<leader>td", gs.toggle_deleted, opts)
+
+        -- Text object
+        map({ "o", "x" }, "ih", ":<C-U>Gitsigns select_hunk<CR>", opts)
+      end
+    }
+  end
+}