Add "pre-event" hooks

README.md

@@ -557,6 +557,33 @@ This works for just about everything that has an object-ID in git, and if you fi
 
 See the built-in documentation for a comprehensive list of highlight groups. If your theme doesn't style a particular group, we'll try our best to do a nice job.
 
+## Hooks
+
+Neogit supports hooks for the following actions:
+
+| Hook                 | Description                                      | Hook Data                                                            |
+| -------------------- | ------------------------------------------------ | -------------------------------------------------------------------- |
+| `PreStatusRefreshed` | Before a status is reloaded                      | `{}`                                                                 |
+| `PreCommit`          | Before a commit has been created                 | `{}`                                                                 |
+| `PrePush`            | Before a push is made                            | `{}`                                                                 |
+| `PrePull`            | Before a pull is made                            | `{}`                                                                 |
+| `PreFetch`           | Before a fetch is made                           | `{}`                                                                 |
+| `PreBranchCreate`    | Before a branch is created, starting from `base` | `{ branch_name: string, base: string? }`                             |
+| `PreBranchDelete`    | Before a branch is deleted                       | `{ branch_name: string }`                                            |
+| `PreBranchCheckout`  | Before a branch is checked out                   | `{ branch_name: string }`                                            |
+| `PreBranchReset`     | Before a branch is reset to a commit/branch      | `{ branch_name: string, resetting_to: string }`                      |
+| `PreBranchRename`    | Before a branch is renamed                       | `{ branch_name: string, new_name: string }`                          |
+| `PreRebase`          | Before a rebase is started                       | `{ commit: string }`                                                 |
+| `PreReset`           | Before a branch is reset to a certain commit     | `{ commit: string, mode: "soft"\|"mixed"\|"hard"\|"keep"\|"index" }` |
+| `PreTagCreate`       | Before a tag is placed on a certain commit       | `{ name: string, ref: string }`                                      |
+| `PreTagDelete`       | Before one or more tags are removed              | `{ names: string[] }`                                                |
+| `PreCherryPick`      | Before one or more commits are cherry-picked     | `{ commits: string[] }`                                              |
+| `PreMerge`           | Before a merge is started                        | `{ branch: string, args = string[] }`                                |
+| `PreStash`           | Before a stash is made                           | `{}`                                                                 |
+| `PreRefsRefreshed`   | Before refs are refreshed                        | `{}`                                                                 |
+| `PreDiffLoaded`      | Before a diff is loaded                          | `{?}`                                                                |
+| `PreBisect`          | Before a bisect is started                       | `{ type: string }`                                                   |
+| `PreWorktreeCreate`  | Before a worktree is created                     | `{ ref: string, path: string }`                                      |
 
 ## Events
 

lua/neogit/buffers/refs_view/init.lua

@@ -3,6 +3,7 @@ local config = require("neogit.config")
 local ui = require("neogit.buffers.refs_view.ui")
 local popups = require("neogit.popups")
 local status_maps = require("neogit.config").get_reversed_status_maps()
+local hook = require("neogit.lib.hook")
 local mapping = config.get_reversed_refs_view_maps()
 local CommitViewBuffer = require("neogit.buffers.commit_view")
 local Watcher = require("neogit.watcher")
@@ -327,6 +328,7 @@ function M:open()
 end
 
 function M:redraw()
+  hook.run("PreRefsRefreshed")
   logger.debug("[REFS] Beginning redraw")
   self.buffer.ui:render(unpack(ui.RefsView(git.refs.list_parsed(), self.head)))
 

lua/neogit/buffers/status/init.lua

@@ -7,6 +7,7 @@ local Watcher = require("neogit.watcher")
 local a = require("plenary.async")
 local logger = require("neogit.logger") -- TODO: Add logging
 local event = require("neogit.lib.event")
+local hook = require("neogit.lib.hook")
 
 ---@class Semaphore
 ---@field permits number
@@ -319,6 +320,7 @@ function M:refresh(partial, reason)
     source = "status",
     partial = partial,
     callback = function()
+      hook.run("PreStatusRefreshed")
       self:redraw(cursor, view)
       event.send("StatusRefreshed")
       logger.info("[STATUS] Refresh complete")

lua/neogit/buffers/status/ui.lua

@@ -6,6 +6,7 @@ local config = require("neogit.config")
 local a = require("plenary.async")
 local state = require("neogit.lib.state")
 local event = require("neogit.lib.event")
+local hook = require("neogit.lib.hook")
 
 local col = Ui.col
 local row = Ui.row
@@ -238,6 +239,7 @@ local SectionItemFile = function(section, config)
           end
         end
 
+        hook.run("PreDiffLoaded", { diff = diff }) -- TODO: what should the data be?
         ui.buf:with_locked_viewport(function()
           this:append(DiffHunks(diff))
           ui:update()

lua/neogit/config.lua

@@ -323,6 +323,29 @@ end
 ---| "author-date"
 ---| "date"
 
+---@alias NeogitHook
+---| "PreStatusRefreshed"
+---| "PreCommit"
+---| "PrePush"
+---| "PrePull"
+---| "PreFetch"
+---| "PreBranchCreate"
+---| "PreBranchDelete"
+---| "PreBranchCheckout"
+---| "PreBranchReset"
+---| "PreBranchRename"
+---| "PreRebase"
+---| "PreReset"
+---| "PreTagCreate"
+---| "PreTagDelete"
+---| "PreCherryPick"
+---| "PreMerge"
+---| "PreStash"
+---| "PreRefsRefreshed"
+---| "PreDiffLoaded"
+---| "PreBisect"
+---| "PreWorktreeCreate"
+
 ---@class NeogitConfigStatusOptions
 ---@field recent_commit_count? integer The number of recent commits to display
 ---@field mode_padding? integer The amount of padding to add to the right of the mode column
@@ -401,6 +424,7 @@ end
 ---@field treesitter_diff_highlight? boolean Apply syntax highlighting to diff hunks via treesitter
 ---@field word_diff_highlight? boolean Apply word-diff highlighting to diff hunks
 ---@field builders? { [string]: fun(builder: PopupBuilder) }
+---@field hooks? { [NeogitHook]: fun(data: table?) }
 
 ---Returns the default Neogit configuration
 ---@return NeogitConfig
@@ -419,6 +443,7 @@ function M.get_default_values()
     log_date_format = nil,
     log_pager = nil,
     process_spinner = false,
+    hooks = {},
     filewatcher = {
       enabled = true,
     },

lua/neogit/lib/git/bisect.lua

@@ -1,5 +1,6 @@
 local git = require("neogit.lib.git")
 local event = require("neogit.lib.event")
+local hook = require("neogit.lib.hook")
 
 ---@class NeogitGitBisect
 local M = {}
@@ -25,6 +26,7 @@ end
 ---@param good_revision string
 ---@param args? table
 function M.start(bad_revision, good_revision, args)
+  hook.run("PreBisect", { type = "start" })
   local result =
     git.cli.bisect.args("start").arg_list(args).args(bad_revision, good_revision).call { long = true }
 

lua/neogit/lib/git/cherry_pick.lua

@@ -3,6 +3,7 @@ local notification = require("neogit.lib.notification")
 local util = require("neogit.lib.util")
 local client = require("neogit.client")
 local event = require("neogit.lib.event")
+local hook = require("neogit.lib.hook")
 
 ---@class NeogitGitCherryPick
 local M = {}
@@ -13,6 +14,7 @@ local M = {}
 function M.pick(commits, args)
   local cmd = git.cli["cherry-pick"].arg_list(util.merge(args, commits))
 
+  hook.run("PreCherryPick", { commits = commits })
   local result
   if vim.tbl_contains(args, "--edit") then
     result = cmd.env(client.get_envs_git_editor()).call { pty = true }
@@ -36,6 +38,7 @@ function M.apply(commits, args)
     end
   end)
 
+  hook.run("PreCherryPick", { commits = commits })
   local result = git.cli["cherry-pick"].no_commit.arg_list(util.merge(args, commits)).call { await = true }
   if result:failure() then
     notification.error("Cherry Pick failed. Resolve conflicts before continuing")

lua/neogit/lib/git/fetch.lua

@@ -1,4 +1,5 @@
 local git = require("neogit.lib.git")
+local hook = require("neogit.lib.hook")
 
 ---@class NeogitGitFetch
 local M = {}
@@ -9,13 +10,15 @@ local M = {}
 ---@param args string[]
 ---@return ProcessResult
 function M.fetch_interactive(remote, branch, args)
+  hook.run("PreFetch")
   return git.cli.fetch.args(remote or "", branch or "").arg_list(args).call { pty = true }
 end
 
 ---@param remote string
 ---@param branch string
 ---@return ProcessResult
 function M.fetch(remote, branch)
+  hook.run("PreFetch")
   return git.cli.fetch.args(remote, branch).call { ignore_error = true }
 end
 

lua/neogit/lib/git/merge.lua

@@ -2,6 +2,7 @@ local client = require("neogit.client")
 local git = require("neogit.lib.git")
 local notification = require("neogit.lib.notification")
 local event = require("neogit.lib.event")
+local hook = require("neogit.lib.hook")
 
 ---@class NeogitGitMerge
 local M = {}
@@ -11,6 +12,7 @@ local function merge_command(cmd)
 end
 
 function M.merge(branch, args)
+  hook.run("PreMerge", { branch = branch, args = args })
   local result = merge_command(git.cli.merge.args(branch).arg_list(args))
   if result:failure() then
     notification.error("Merging failed. Resolve conflicts before continuing")

lua/neogit/lib/git/pull.lua

@@ -1,12 +1,14 @@
 local git = require("neogit.lib.git")
 local util = require("neogit.lib.util")
+local hook = require("neogit.lib.hook")
 
 ---@class NeogitGitPull
 local M = {}
 
 function M.pull_interactive(remote, branch, args)
   local client = require("neogit.client")
   local envs = client.get_envs_git_editor()
+  hook.run("PrePull")
   return git.cli.pull.env(envs).args(remote or "", branch or "").arg_list(args).call { pty = true }
 end
 

lua/neogit/lib/git/push.lua

@@ -1,5 +1,6 @@
 local git = require("neogit.lib.git")
 local util = require("neogit.lib.util")
+local hook = require("neogit.lib.hook")
 
 ---@class NeogitGitPush
 local M = {}
@@ -10,6 +11,7 @@ local M = {}
 ---@param args string[]
 ---@return ProcessResult
 function M.push_interactive(remote, branch, args)
+  hook.run("PrePush")
   return git.cli.push.args(remote or "", branch or "").arg_list(args).call { pty = true }
 end
 

lua/neogit/lib/git/rebase.lua

@@ -3,6 +3,7 @@ local git = require("neogit.lib.git")
 local client = require("neogit.client")
 local notification = require("neogit.lib.notification")
 local event = require("neogit.lib.event")
+local hook = require("neogit.lib.hook")
 
 ---@class NeogitGitRebase
 local M = {}
@@ -16,6 +17,7 @@ end
 ---@param args? string[] list of arguments to pass to git rebase
 ---@return ProcessResult
 function M.instantly(commit, args)
+  hook.run("PreRebase", { commit = commit })
   local result = git.cli.rebase.interactive.autostash.autosquash
     .commit(commit)
     .env({ GIT_SEQUENCE_EDITOR = ":", GIT_EDITOR = ":" })
@@ -36,6 +38,7 @@ function M.rebase_interactive(commit, args)
     commit = ""
   end
 
+  hook.run("PreRebase", { commit = commit })
   local result = rebase_command(git.cli.rebase.interactive.arg_list(args).args(commit))
   if result:failure() then
     if result.stdout[1]:match("^hint: Waiting for your editor to close the file%.%.%. error") then
@@ -52,6 +55,7 @@ function M.rebase_interactive(commit, args)
 end
 
 function M.onto_branch(branch, args)
+  hook.run("PreRebase", { commit = branch })
   local result = rebase_command(git.cli.rebase.args(branch).arg_list(args))
   if result:failure() then
     notification.error("Rebasing failed. Resolve conflicts before continuing")
@@ -67,6 +71,7 @@ function M.onto(start, newbase, args)
     start = ""
   end
 
+  hook.run("PreRebase", { commit = newbase })
   local result = rebase_command(git.cli.rebase.onto.args(newbase, start).arg_list(args))
   if result:failure() then
     notification.error("Rebasing failed. Resolve conflicts before continuing")
@@ -80,6 +85,7 @@ end
 ---@param commit string rev name of the commit to reword
 ---@return ProcessResult|nil
 function M.reword(commit)
+  hook.run("PreCommit")
   local message = table.concat(git.log.full_message(commit), "\n")
   local status = client.wrap(
     git.cli.commit.only.allow_empty.edit.with_message(("amend! %s\n\n%s"):format(commit, message)),
@@ -99,6 +105,7 @@ end
 function M.modify(commit)
   local short_commit = git.rev_parse.abbreviate_commit(commit)
   local editor = "nvim -c '%s/^pick \\(" .. short_commit .. ".*\\)/edit \\1/' -c 'wq'"
+  hook.run("PreRebase", { commit = commit })
   local result = git.cli.rebase.interactive.autosquash.autostash
     .commit(commit)
     .in_pty(true)
@@ -113,6 +120,7 @@ end
 function M.drop(commit)
   local short_commit = git.rev_parse.abbreviate_commit(commit)
   local editor = "nvim -c '%s/^pick \\(" .. short_commit .. ".*\\)/drop \\1/' -c 'wq'"
+  hook.run("PreRebase", { commit = commit })
   local result = git.cli.rebase.interactive.autosquash.autostash
     .commit(commit)
     .in_pty(true)

lua/neogit/lib/git/stash.lua

@@ -3,6 +3,7 @@ local input = require("neogit.lib.input")
 local util = require("neogit.lib.util")
 local config = require("neogit.config")
 local event = require("neogit.lib.event")
+local hook = require("neogit.lib.hook")
 
 ---@class NeogitGitStash
 local M = {}
@@ -18,28 +19,33 @@ end
 
 ---@param args string[]
 function M.stash_all(args)
+  hook.run("PreStash")
   local result = git.cli.stash.push.files(".").arg_list(args).call()
   event.send("Stash", { success = result:success() })
 end
 
 function M.stash_index()
+  hook.run("PreStash")
   local result = git.cli.stash.staged.call()
   event.send("Stash", { success = result:success() })
 end
 
 function M.stash_keep_index()
+  hook.run("PreStash")
   local result = git.cli.stash.keep_index.files(".").call()
   event.send("Stash", { success = result:success() })
 end
 
 ---@param args string[]
 ---@param files string[]
 function M.push(args, files)
+  hook.run("PreStash")
   local result = git.cli.stash.push.arg_list(args).files(unpack(files)).call()
   event.send("Stash", { success = result:success() })
 end
 
 function M.pop(stash)
+  hook.run("PreStash")
   local result = git.cli.stash.apply.index.args(stash).call()
 
   if result:success() then
@@ -52,6 +58,7 @@ function M.pop(stash)
 end
 
 function M.apply(stash)
+  hook.run("PreStash")
   local result = git.cli.stash.apply.index.args(stash).call()
 
   if result:failure() then
@@ -62,6 +69,7 @@ function M.apply(stash)
 end
 
 function M.drop(stash)
+  hook.run("PreStash")
   local result = git.cli.stash.drop.args(stash).call()
   event.send("Stash", { success = result:success() })
 end

lua/neogit/lib/git/worktree.lua

@@ -1,6 +1,7 @@
 local git = require("neogit.lib.git")
 local util = require("neogit.lib.util")
 local Path = require("plenary.path")
+local hook = require("neogit.lib.hook")
 
 ---@class NeogitGitWorktree
 local M = {}
@@ -10,6 +11,7 @@ local M = {}
 ---@param path string absolute path
 ---@return boolean, string
 function M.add(ref, path, params)
+  hook.run("PreWorktreeCreate", { ref = ref, path = path })
   local result = git.cli.worktree.add.arg_list(params or {}).args(path, ref).call()
   if result:success() then
     return true, ""

lua/neogit/lib/hook.lua

@@ -0,0 +1,15 @@
+local M = {}
+
+local config = require("neogit.config")
+
+---@param name NeogitHook
+---@param data table?
+function M.run(name, data)
+  assert(name, "hook must have name")
+
+  if config.values.hooks[name] then
+    config.values.hooks[name](data)
+  end
+end
+
+return M