feat: Implement mercurial (hg) adapter

doc/diffview.txt

@@ -179,75 +179,120 @@ COMMANDS                                        *diffview-commands*
             :'<,'>DiffviewFileHistory
 <
 
-    Options: ~
+    What options are available will be determined by what type of repository
+    you're targeting. You will find the available options for the supported
+    VCS tools below. The command completion will do it's best to suggest the
+    appropriate options.
+
+    Git Options: ~
         --base={git-rev}
-                        Specify a base git rev from which the right side of
-                        the diff will be created. Use the special value
-                        `LOCAL` to use the local version of the file.
+                Specify a base git rev from which the right side of the diff
+                will be created. Use the special value `LOCAL` to use the
+                local version of the file.
 
         --range={git-rev}
-                        Show only commits in the specified revision range.
+                Show only commits in the specified revision range.
 
-        -C{path}        Run as if git was started in {path} instead of the
-                        current working directory.
+        -C{path}
+                Run as if git was started in {path} instead of the current
+                working directory.
 
         NOTE: All following options are described in far more detail in the
         man page for git-log. See `:Man git-log(1)` for more information.
 
-        --follow        Follow renames (only for single file).
+        --follow
+                Follow renames (only for single file).
 
-        --first-parent  Follow only the first parent upon seeing a merge
-                        commit.
+        --first-parent
+                Follow only the first parent upon seeing a merge commit.
 
-        --show-pulls    Show merge commits that are not TREESAME to its first
-                        parent, but are to a later parent.
+        --show-pulls
+                Show merge commits that are not TREESAME to its first parent,
+                but are to a later parent.
 
-        --reflog        Include all reachable objects mentioned by reflogs.
+        --reflog
+                Include all reachable objects mentioned by reflogs.
 
-        --all           Include all refs.
+        --all   Include all refs.
 
-        --merges        List only merge commits.
+        --merges
+                List only merge commits.
 
-        --no-merges     List no merge commits.
+        --no-merges
+                List no merge commits.
 
-        --reverse       List commits in reverse order.
+        --reverse
+                List commits in reverse order.
 
         -n{n}, --max-count={n}
-                        Limit the number of commits.
+                Limit the number of commits.
 
         -L{start},{end}:{file}, -L:{funcname}:{file}
-                        Trace the evolution of the line range given by
-                        {start},{end}, or by the function name regex
-                        {funcname}, within the {file}. You can specify this
-                        option more than once.
+                Trace the evolution of the line range given by {start},{end},
+                or by the function name regex {funcname}, within the {file}.
+                You can specify this option more than once.
 
         --diff-merges={value}
-                        Determines how merge commits are treated. {value} can
-                        be one of:
-                            • `off`
-                            • `on`
-                            • `first-parent`
-                            • `separate`
-                            • `combined`
-                            • `dense-combined`
-                            • `remerge`
+                Determines how merge commits are treated. {value} can
+                be one of:
+                    • `off`
+                    • `on`
+                    • `first-parent`
+                    • `separate`
+                    • `combined`
+                    • `dense-combined`
+                    • `remerge`
 
         --author={pattern}
-                        Limit the commits output to ones with author/committer
-                        header lines that match the specified {pattern}
-                        (regular expression).
+                Limit the commits output to ones with author/committer header
+                lines that match the specified {pattern} (regular expression).
 
         --grep={pattern}
-                        Limit the commits output to ones with log message that
-                        matches the specified {pattern} (regular expression).
+                Limit the commits output to ones with log message that matches
+                the specified {pattern} (regular expression).
 
-        -G{pattern}     Look for differences whose patch text contains
-                        added/removed lines that match {pattern} (extended
-                        regular expression).
+        -G{pattern}
+                Look for differences whose patch text contains added/removed
+                lines that match {pattern} (extended regular expression).
 
-        -S{pattern}     Look for differences that change the number of
-                        occurences of the specified {pattern} (extended
-                        regular expression) in a file.
+        -S{pattern}
+                Look for differences that change the number of occurences of
+                the specified {pattern} (extended regular expression) in a
+                file.
+
+    Mercurial Options: ~
+
+        --rev={rev}
+                Show only commits for the specified revset {rev}.
+                See `hg help revsets` for the full list of keywords and
+                constructs.
+
+        -f, --follow
+                Follow renames (only for single file).
+
+        -l{n}, --limit={n}
+                Limit the number of commits.
+
+        -M, --no-merges
+                Do not list merge commits.
+
+        --user={text}
+                Limit the commits to ones with user as specified.
+
+        --keyword={text}
+                Limit commits to ones matching the {text} in the log message.
+
+        --branch={text}
+                Limit commits to a specified branch.
+
+        --bookmark={text}
+                Limit commits to a specified bookmark
+
+        --include={pattern}
+                Include commits touching files as specified in the {pattern}.
+
+        --exclude={pattern}
+                Exclude commits touching files as specified in the {pattern}.
 
                                                 *:DiffviewClose*
 :DiffviewClose          Close the active Diffview.
@@ -285,10 +330,20 @@ enhanced_diff_hl                                *diffview-config-enhanced_diff_h
 git_cmd                                         *diffview-config-git_cmd*
         Type: `string[]`, Default: `{ "git" }`
 
-        This table forms the first part of all git commands used internally in
-        the plugin. The first element should be the git binary. The subsequent
+        This table forms the first part of all Git commands used internally in
+        the plugin. The first element should be the Git binary. The subsequent
         elements are passed as arguments.
 
+hg_cmd                                         *diffview-config-hg_cmd*
+        Type: `string[]`, Default: `{ "hg" }`
+
+        This table forms the first part of all Mercurial commands used
+        internally in the plugin. The first element should be the Mercurial
+        binary. The subsequent elements are passed as arguments.
+
+        If your Mercurial install bundles the `chg` binary, this can be
+        configured here to have a significant performance boost.
+
 view.x.layout                                   *diffview-config-view.x.layout*
         Type: >
             "diff1_plain"

lua/diffview/config.lua

@@ -38,6 +38,7 @@ M.defaults = {
   diff_binaries = false,
   enhanced_diff_hl = false,
   git_cmd = { "git" },
+  hg_cmd = { "hg" },
   use_icons = true,
   show_help_hints = true,
   watch_index = true,
@@ -247,6 +248,13 @@ M._config = M.defaults
 ---@field path_args string[]
 
 ---@class HgLogOptions
+---@field limit integer
+---@field user string
+---@field no_merges boolean
+---@field rev string
+---@field keyword string
+---@field include string
+---@field exclude string
 
 ---@alias LogOptions GitLogOptions|HgLogOptions
 
@@ -273,7 +281,15 @@ M.log_option_defaults = {
     path_args = {},
   },
   ---@type HgLogOptions
-  hg = {},
+  hg = {
+    limit = 256,
+    user = nil,
+    no_merges = false,
+    rev = nil,
+    keyword = nil,
+    include = nil,
+    exclude = nil,
+  },
 }
 
 ---@return DiffviewConfig

lua/diffview/scene/views/diff/diff_view.lua

@@ -17,6 +17,7 @@ local debounce = lazy.require("diffview.debounce") ---@module "diffview.debounce
 local logger = lazy.require("diffview.logger") ---@module "diffview.logger"
 local utils = lazy.require("diffview.utils") ---@module "diffview.utils"
 local vcs_utils = lazy.require("diffview.vcs.utils") ---@module "diffview.vcs.utils"
+local GitAdapter = lazy.access("diffview.vcs.adapters.git", "GitAdapter") ---@type GitAdapter|LazyModule
 
 local api = vim.api
 local M = {}
@@ -125,7 +126,7 @@ function DiffView:post_open()
     name = ("diffview://%s/log/%d/%s"):format(self.adapter.ctx.dir, self.tabpage, "commit_log"),
   })
 
-  if config.get_config().watch_index then
+  if config.get_config().watch_index and self.adapter:instanceof(GitAdapter.__get()) then
     self.watcher = vim.loop.new_fs_poll()
     ---@diagnostic disable-next-line: unused-local
     self.watcher:start(self.adapter.ctx.dir .. "/index", 1000, function(err, prev, cur)

lua/diffview/scene/views/file_history/listeners.lua

@@ -33,7 +33,7 @@ return function(view)
       local log_options = view.panel:get_log_options()
       local cur = view.panel:cur_file()
 
-      if log_options.L[1] and bufnr == cur.layout:get_main_win().file.bufnr then
+      if log_options.L and log_options.L[1] and bufnr == cur.layout:get_main_win().file.bufnr then
         for _, value in ipairs(log_options.L) do
           local l1, lpath = value:match("^(%d+),.*:(.*)")
 

lua/diffview/vcs/adapter.lua

@@ -329,7 +329,7 @@ VCSAdapter.show = async.wrap(function(self, path, rev, callback)
     cwd = self.ctx.toplevel,
     ---@type Job
     on_exit = async.void(function(j)
-      local context = "vcs.utils.show()"
+      local context = "VCSAdapter.show()"
       utils.handle_job(j, {
         fail_on_empty = true,
         context = context,

lua/diffview/vcs/adapters/hg/commit.lua

@@ -0,0 +1,42 @@
+local lazy = require("diffview.lazy")
+local oop = require('diffview.oop')
+local utils = require("diffview.utils")
+local Commit = require('diffview.vcs.commit').Commit
+
+local M = {}
+
+---@class HgCommit : Commit
+local HgCommit = oop.create_class('HgCommit', Commit)
+
+function HgCommit:init(opt)
+  HgCommit:super().init(self, opt)
+
+  if opt.time_offset then
+    self.time_offset = HgCommit.parse_time_offset(opt.time_offset)
+    self.time = self.time - self.time_offset
+  else
+    self.time_offset = 0
+  end
+
+  self.iso_date = Commit.time_to_iso(self.time, self.time_offset)
+end
+
+---@param iso_date string?
+function HgCommit.parse_time_offset(iso_date)
+  if not iso_date or iso_date == "" then
+    return 0
+  end
+
+  local sign, offset = vim.trim(iso_date):match("([+-])(%d+)")
+
+  offset = tonumber(offset)
+
+  if sign == "-" then
+    offset = -offset
+  end
+
+  return offset
+end
+
+M.HgCommit = HgCommit
+return M