Follow-up: Require Different Reviewers

This plugin previously only supported the Delta reviewer. Thanks to work
from @mrparalon it now supports Diffview also. This MR adjusts the
requirements to account for this, and the README.

It also addresses a small bug in the original implementation regarding
an async file opening action, and applies formatting to the diffview
file consistent with the rest of the project

README.md

@@ -17,11 +17,11 @@ https://github.com/harrisoncramer/gitlab.nvim/assets/32515581/ab5a8597-32fa-4a28
 
 - <a href="https://go.dev/">Go >= v1.19</a>
 - <a href="https://www.gnu.org/software/make/manual/make.html">make (for install)</a>
-- <a href="https://github.com/dandavison/delta">delta</a>
 
 ## Quick Start
 
-1. Install Go and Delta Dependencies
+1. Install Go
+2. Install reviewer: <a href="https://github.com/dandavison/delta">delta</a> or <a href="https://github.com/sindrets/diffview.nvim">diffview</a>
 2. Add configuration (see Installation section)
 3. Checkout your feature branch: `git checkout feature-branch`
 4. Open Neovim
@@ -42,7 +42,7 @@ return {
   },
   build = function () require("gitlab.server").build(true) end, -- Builds the Go binary
   config = function()
-    require("gitlab").setup()
+    require("gitlab").setup() -- Uses delta reviewer by default
   end,
 }
 ```
@@ -87,7 +87,7 @@ Here is the default setup function. All of these values are optional, and if you
 require("gitlab").setup({
   port = 21036, -- The port of the Go server, which runs in the background
   log_path = vim.fn.stdpath("cache") .. "/gitlab.nvim.log", -- Log path for the Go server
-  reviewer = "delta", -- The reviewer type (only delta is currently supported)
+  reviewer = "delta", -- The reviewer type ("delta" or "diffview")
   popup = { -- The popup for comment creation, editing, and replying
     exit = "<Esc>",
     perform_action = "<leader>s", -- Once in normal mode, does action (like saving comment or editing description, etc)
@@ -108,7 +108,7 @@ require("gitlab").setup({
     resolved = '✓', -- Symbol to show next to resolved discussions
     unresolved = '✖', -- Symbol to show next to unresolved discussions
   },
-  review_pane = { -- Specific settings for different reviewers, only delta currently supported
+  review_pane = { -- Specific settings for different reviewers
     delta = {
       added_file = "", -- The symbol to show next to added files
       modified_file = "", -- The symbol to show next to modified files

lua/gitlab/async.lua

@@ -3,6 +3,7 @@
 local server = require("gitlab.server")
 local job    = require("gitlab.job")
 local state  = require("gitlab.state")
+local u      = require("gitlab.utils")
 
 local M      = {}
 

lua/gitlab/init.lua

@@ -20,6 +20,7 @@ return {
     state.setPluginConfiguration() -- Sets configuration from `.gitlab.nvim` file
     state.merge_settings(args)     -- Sets keymaps and other settings from setup function
     reviewer.init()                -- Picks and initializes reviewer (default is Delta)
+    u.has_reviewer(args.reviewer or "delta")
   end,
   -- Global Actions 🌎
   summary            = async.sequence({ info }, summary.summary),

lua/gitlab/reviewer/diffview.lua

@@ -1,71 +1,79 @@
--- This Module contains all of the code specific to the Delta reviewer.
-local state    = require("gitlab.state")
-local u        = require("gitlab.utils")
+-- This Module contains all of the code specific to the Diffview reviewer.
+local state           = require("gitlab.state")
+local async_ok, async = pcall(require, "diffview.async")
 
-local M        = {
-    bufnr = nil,
-    tabnr = nil
+local M               = {
+  bufnr = nil,
+  tabnr = nil
 }
 
 -- Public Functions
 -- These functions are exposed externally and are used
 -- when the reviewer is consumed by other code. They must follow the specification
 -- outlined in the reviewer/init.lua file
-M.open         = function()
-    vim.api.nvim_command(string.format("DiffviewOpen %s", state.INFO.target_branch))
-    M.tabnr = vim.api.nvim_get_current_tabpage()
+M.open                = function()
+  vim.api.nvim_command(string.format("DiffviewOpen %s", state.INFO.target_branch))
+  M.tabnr = vim.api.nvim_get_current_tabpage()
 end
 
-M.jump         = function(file_name, new_line, old_line)
-    if M.tabnr == nil then
-        vim.notify("Can't jump to Diffvew. Is it open?", vim.log.levels.ERROR)
+M.jump                = function(file_name, new_line, old_line)
+  if M.tabnr == nil then
+    vim.notify("Can't jump to Diffvew. Is it open?", vim.log.levels.ERROR)
+    return
+  end
+  vim.api.nvim_set_current_tabpage(M.tabnr)
+  vim.cmd("DiffviewFocusFiles")
+  local view = require("diffview.lib").get_current_view()
+  if view == nil then
+    vim.notify("Could not find Diffview view", vim.log.levels.ERROR)
+    return
+  end
+  local files = view.panel:ordered_file_list()
+  local layout = view.cur_layout
+  for _, file in ipairs(files) do
+    if file.path == file_name then
+      if not async_ok then
+        vim.notify("Could not load Diffview async", vim.log.levels.ERROR)
         return
+      end
+      async.await(view:set_file(file))
+      if new_line ~= nil then
+        layout.b:focus()
+        vim.api.nvim_win_set_cursor(0, { tonumber(new_line), 0 })
+      elseif old_line ~= nil then
+        layout.a:focus()
+        vim.api.nvim_win_set_cursor(0, { tonumber(old_line), 0 })
+      end
+      break
     end
-    vim.api.nvim_set_current_tabpage(M.tabnr)
-    vim.cmd("DiffviewFocusFiles")
-    local view = require("diffview.lib").get_current_view()
-    if view == nil then
-        vim.notify("Could not find Diffview view", vim.log.levels.ERROR)
-        return
-    end
-    local files = view.panel:ordered_file_list()
-    local layout = view.cur_layout
-    for _, file in ipairs(files) do
-        if file.path == file_name then
-            view:set_file(file)
-            if new_line ~= nil then
-                layout.b:focus()
-                vim.api.nvim_win_set_cursor(0, { tonumber(new_line), 0 })
-            elseif old_line ~= nil then
-                layout.a:focus()
-                vim.api.nvim_win_set_cursor(0, { tonumber(old_line), 0 })
-            end
-            break
-        end
-    end
+  end
 end
 
-M.get_location = function()
-    if M.tabnr == nil then return nil, nil, "Diffview reviewer must be initialized first" end
-    local bufnr = vim.api.nvim_get_current_buf()
-    -- check if we are in the diffview tab
-    local tabnr = vim.api.nvim_get_current_tabpage()
-    if tabnr ~= M.tabnr then return nil, nil, "Line location can only be determined within reviewer window" end
-    -- check if we are in the diffview buffer
-    local view = require("diffview.lib").get_current_view()
-    local layout = view.cur_layout
-    local file_name = nil
-    local current_line_changes = nil
-    if layout.a.file.bufnr == bufnr then
-        file_name = layout.a.file.path
-        current_line_changes = { new_line = nil, old_line = vim.api.nvim_win_get_cursor(0)[1] }
-        return file_name, current_line_changes
-    elseif layout.b.file.bufnr == bufnr then
-        file_name = layout.b.file.path
-        current_line_changes = { new_line = vim.api.nvim_win_get_cursor(0)[1], old_line = nil }
-        return file_name, current_line_changes
-    end
-    return nil, nil, "Line location can only be determined within reviewer window"
+M.get_location        = function()
+  if M.tabnr == nil then return nil, nil, "Diffview reviewer must be initialized first" end
+  local bufnr = vim.api.nvim_get_current_buf()
+  -- check if we are in the diffview tab
+  local tabnr = vim.api.nvim_get_current_tabpage()
+  if tabnr ~= M.tabnr then return nil, nil, "Line location can only be determined within reviewer window" end
+  -- check if we are in the diffview buffer
+  local view = require("diffview.lib").get_current_view()
+  if view == nil then
+    vim.notify("Could not find Diffview view", vim.log.levels.ERROR)
+    return
+  end
+  local layout = view.cur_layout
+  local file_name = nil
+  local current_line_changes = nil
+  if layout.a.file.bufnr == bufnr then
+    file_name = layout.a.file.path
+    current_line_changes = { new_line = nil, old_line = vim.api.nvim_win_get_cursor(0)[1] }
+    return file_name, current_line_changes
+  elseif layout.b.file.bufnr == bufnr then
+    file_name = layout.b.file.path
+    current_line_changes = { new_line = vim.api.nvim_win_get_cursor(0)[1], old_line = nil }
+    return file_name, current_line_changes
+  end
+  return nil, nil, "Line location can only be determined within reviewer window"
 end
 
 return M

lua/gitlab/server.lua

@@ -43,11 +43,6 @@ end
 
 -- Builds the Go binary
 M.build = function(override)
-  if not u.has_delta() then
-    vim.notify("Please install delta to use gitlab.nvim!", vim.log.levels.ERROR)
-    return
-  end
-
   local file_path = u.current_file_path()
   local parent_dir = vim.fn.fnamemodify(file_path, ":h:h:h:h")
   state.settings.bin_path = parent_dir

lua/gitlab/utils/init.lua

@@ -4,8 +4,19 @@ M.get_current_line_number = function()
   return vim.api.nvim_call_function('line', { '.' })
 end
 
-M.has_delta = function()
-  return vim.fn.executable("delta") == 1
+M.has_reviewer = function(reviewer)
+  local has_reviewer = false
+  if reviewer == "diffview" then
+    has_reviewer = vim.fn.exists(":DiffviewOpen") ~= 0
+  else
+    has_reviewer = vim.fn.executable("delta") == 1
+  end
+
+  if not has_reviewer then
+    error(string.format("Please install %s or change your reviewer", reviewer))
+  end
+
+  return has_reviewer
 end
 
 M.P = function(...)