feat(nixvim): add AI review workflow

README.md

@@ -88,12 +88,15 @@ home-manager.users.<user>.home.packages = [
 
 ### Git
 
+- `codediff.nix`: Configures a read-only review workflow for working-tree, branch, and commit-history diffs.
 - `jj.nix`: Configures Jujutsu commands and key mappings.
 - `lazygit.nix`: Configures the LazyGit plugin for Git integration.
-- `gitsigns.nix`: Configures the GitSigns plugin for displaying Git diff information.
+- `gitsigns.nix`: Configures GitSigns diff markers, hunk navigation, inline previews, blame, and word diffs.
 
 ### Utils
 
+- `trouble.nix`: Provides persistent diagnostics, quickfix, location-list, and TODO triage views.
+- `overseer.nix`: Runs bounded, repo-aware validation tasks while keeping persistent sessions in cmux.
 - `telescope.nix`: Configures the Telescope plugin for fuzzy finding and picking.
 - `whichkey.nix`: Configures the WhichKey plugin for displaying key mappings.
 - `extra_plugins.nix`: Configures additional plugins.

config/default.nix

@@ -44,11 +44,14 @@ _: {
     ./plugins/lsp/fidget.nix
 
     # Git
+    ./plugins/git/codediff.nix
     ./plugins/git/jj.nix
     ./plugins/git/lazygit.nix
     ./plugins/git/gitsigns.nix
 
     # Utils
+    ./plugins/utils/trouble.nix
+    ./plugins/utils/overseer.nix
     ./plugins/utils/telescope.nix
     ./plugins/utils/whichkey.nix
     ./plugins/utils/extra_plugins.nix

config/plugins/git/codediff.nix

@@ -0,0 +1,143 @@
+{ lib, ... }:
+let
+  reviewLua = # lua
+    ''
+      local function git_root()
+        local name = vim.api.nvim_buf_get_name(0)
+        local start = name ~= "" and vim.fs.dirname(name) or vim.uv.cwd()
+        return (start and vim.fs.root(start, ".git")) or vim.uv.cwd()
+      end
+
+      local function git_ref_exists(root, ref)
+        local result = vim.system(
+          { "git", "rev-parse", "--verify", "--quiet", ref },
+          { cwd = root, text = true }
+        ):wait()
+        return result.code == 0
+      end
+
+      local function review_base()
+        local root = git_root()
+        local result = vim.system(
+          { "git", "symbolic-ref", "--quiet", "--short", "refs/remotes/origin/HEAD" },
+          { cwd = root, text = true }
+        ):wait()
+
+        if result.code == 0 then
+          local ref = vim.trim(result.stdout or "")
+          if ref ~= "" then
+            return ref
+          end
+        end
+
+        for _, ref in ipairs({ "origin/main", "origin/master", "main", "master" }) do
+          if git_ref_exists(root, ref) then
+            return ref
+          end
+        end
+
+        return nil
+      end
+
+      local function with_review_base(callback)
+        local base = review_base()
+        if not base then
+          vim.notify("Could not determine the default review branch", vim.log.levels.ERROR)
+          return
+        end
+        callback(base)
+      end
+
+      vim.api.nvim_create_user_command("CodeReviewBranch", function()
+        with_review_base(function(base)
+          vim.cmd("CodeDiff " .. vim.fn.fnameescape(base .. "...HEAD"))
+        end)
+      end, { desc = "Review branch changes against its merge base" })
+
+      vim.api.nvim_create_user_command("CodeReviewHistory", function()
+        with_review_base(function(base)
+          vim.cmd("CodeDiff history " .. vim.fn.fnameescape(base .. "..HEAD") .. " --reverse")
+        end)
+      end, { desc = "Review branch commits in chronological order" })
+    '';
+in
+{
+  plugins.codediff = {
+    enable = true;
+    settings = {
+      diff = {
+        layout = "side-by-side";
+        compact = true;
+        compact_context_lines = 4;
+        compute_moves = true;
+        cycle_hunks_across_files = true;
+        disable_inlay_hints = true;
+        jump_to_first_change = true;
+      };
+      explorer = {
+        initial_focus = "explorer";
+        view_mode = "tree";
+      };
+      history = {
+        initial_focus = "history";
+        view_mode = "tree";
+      };
+      keymaps = {
+        conflict = {
+          accept_all_both = false;
+          accept_all_current = false;
+          accept_all_incoming = false;
+          accept_both = false;
+          accept_current = false;
+          accept_incoming = false;
+          diffget_current = false;
+          diffget_incoming = false;
+          discard = false;
+          discard_all = false;
+        };
+        view = {
+          diff_get = false;
+          diff_put = false;
+          discard_hunk = false;
+          stage_hunk = false;
+          toggle_stage = false;
+          unstage_hunk = false;
+        };
+        explorer = {
+          restore = false;
+          stage_all = false;
+          unstage_all = false;
+        };
+      };
+    };
+  };
+
+  extraConfigLua = lib.mkAfter reviewLua;
+
+  keymaps = [
+    {
+      mode = "n";
+      key = "<leader>gd";
+      action = "<cmd>CodeDiff<cr>";
+      options = {
+        desc = "Review working tree";
+      };
+    }
+    {
+      mode = "n";
+      key = "<leader>gD";
+      action = "<cmd>CodeReviewBranch<cr>";
+      options = {
+        desc = "Review branch changes";
+      };
+    }
+    {
+      mode = "n";
+      key = "<leader>gH";
+      action = "<cmd>CodeReviewHistory<cr>";
+      options = {
+        desc = "Review branch history";
+      };
+    }
+  ];
+}

config/plugins/git/gitsigns.nix

@@ -1,7 +1,10 @@
-_: {
+{
   plugins.gitsigns = {
     enable = true;
     settings = {
+      preview_config = {
+        border = "rounded";
+      };
       signs = {
         add = {
           text = " ";
@@ -22,6 +25,50 @@ _: {
           text = "󱂧 ";
         };
       };
+      word_diff = false;
     };
   };
+
+  keymaps = [
+    {
+      mode = "n";
+      key = "]h";
+      action = "<cmd>Gitsigns nav_hunk next<cr>";
+      options = {
+        desc = "Next Git hunk";
+      };
+    }
+    {
+      mode = "n";
+      key = "[h";
+      action = "<cmd>Gitsigns nav_hunk prev<cr>";
+      options = {
+        desc = "Previous Git hunk";
+      };
+    }
+    {
+      mode = "n";
+      key = "<leader>ghp";
+      action = "<cmd>Gitsigns preview_hunk_inline<cr>";
+      options = {
+        desc = "Preview Git hunk inline";
+      };
+    }
+    {
+      mode = "n";
+      key = "<leader>ghb";
+      action = "<cmd>Gitsigns blame_line<cr>";
+      options = {
+        desc = "Blame Git line";
+      };
+    }
+    {
+      mode = "n";
+      key = "<leader>gW";
+      action = "<cmd>Gitsigns toggle_word_diff<cr>";
+      options = {
+        desc = "Toggle Git word diff";
+      };
+    }
+  ];
 }

config/plugins/git/jj.nix

@@ -5,6 +5,7 @@
       cmd.describe.editor = {
         type = "buffer";
       };
+      diff.backend = "codediff";
     };
   };
 

config/plugins/utils/overseer.nix

@@ -0,0 +1,147 @@
+{ lib, ... }:
+let
+  projectTasksLua = # lua
+    ''
+      local overseer = require("overseer")
+
+      local function find_root(marker, start, kind)
+        local opts = {
+          upward = true,
+          path = start,
+        }
+        if kind then
+          opts.type = kind
+        end
+
+        local match = vim.fs.find(marker, opts)[1]
+        return match and vim.fs.dirname(match) or nil
+      end
+
+      local function validation_task(name, description, command, cwd)
+        return {
+          name = name,
+          desc = description,
+          tags = { overseer.TAG.TEST },
+          builder = function()
+            return {
+              cmd = command,
+              cwd = cwd,
+              components = {
+                {
+                  "on_output_quickfix",
+                  items_only = true,
+                  open = false,
+                  set_diagnostics = true,
+                },
+                "default",
+              },
+            }
+          end,
+        }
+      end
+
+      overseer.register_template({
+        name = "project checks",
+        generator = function(search)
+          local tasks = {}
+
+          local flake_root = find_root("flake.nix", search.dir, "file")
+          if flake_root and vim.fn.executable("nix") == 1 then
+            table.insert(tasks, validation_task(
+              "project: nix flake check",
+              "Run flake checks, including untracked files, without changing flake.lock",
+              { "nix", "flake", "check", "path:.", "--no-write-lock-file" },
+              flake_root
+            ))
+          end
+
+          local go_root = find_root("go.mod", search.dir, "file")
+          if go_root and vim.fn.executable("go") == 1 then
+            table.insert(tasks, validation_task(
+              "project: go test ./...",
+              "Run all Go tests in the nearest module",
+              { "go", "test", "./..." },
+              go_root
+            ))
+          end
+
+          local git_root = find_root(".git", search.dir)
+          if git_root and vim.fn.executable("git") == 1 then
+            table.insert(tasks, validation_task(
+              "project: git diff --check",
+              "Check the working tree for whitespace errors",
+              { "git", "diff", "--check" },
+              git_root
+            ))
+          end
+
+          if vim.tbl_isempty(tasks) then
+            return "No supported project checks found"
+          end
+          return tasks
+        end,
+      })
+
+      vim.api.nvim_create_user_command("OverseerRestartLast", function()
+        local task_list = require("overseer.task_list")
+        local tasks = overseer.list_tasks({
+          status = {
+            overseer.STATUS.SUCCESS,
+            overseer.STATUS.FAILURE,
+            overseer.STATUS.CANCELED,
+          },
+          sort = task_list.sort_finished_recently,
+        })
+
+        if vim.tbl_isempty(tasks) then
+          vim.notify("No completed tasks found", vim.log.levels.WARN)
+          return
+        end
+        overseer.run_action(tasks[1], "restart")
+      end, { desc = "Restart the most recently completed task" })
+    '';
+in
+{
+  plugins.overseer = {
+    enable = true;
+    settings = {
+      dap = false;
+      templates = [ "builtin" ];
+      task_list = {
+        default_detail = 1;
+        direction = "bottom";
+        min_height = 10;
+        max_height = 20;
+      };
+    };
+  };
+
+  extraConfigLua = lib.mkAfter projectTasksLua;
+
+  keymaps = [
+    {
+      mode = "n";
+      key = "<leader>or";
+      action = "<cmd>OverseerRun<cr>";
+      options.desc = "Run project task";
+    }
+    {
+      mode = "n";
+      key = "<leader>ot";
+      action = "<cmd>OverseerToggle<cr>";
+      options.desc = "Toggle task list";
+    }
+    {
+      mode = "n";
+      key = "<leader>oa";
+      action = "<cmd>OverseerTaskAction<cr>";
+      options.desc = "Task action";
+    }
+    {
+      mode = "n";
+      key = "<leader>ol";
+      action = "<cmd>OverseerRestartLast<cr>";
+      options.desc = "Restart last task";
+    }
+  ];
+}