feat(file-history): Added --walk-reflogs (#413)

Author: sindrets

USAGE.md

@@ -81,6 +81,17 @@ from the PR branch.
 
 ![file history cherry pick demo](https://user-images.githubusercontent.com/2786478/229853402-f45280ee-f6e2-4325-8a39-ce25b9c5221e.png)
 
+## Inspecting Diffs for Stashes
+
+The latest Git stash is always stored in the reference `refs/stash`. We can
+find all the stashes by traversing the reflog for this reference. This can be
+achieved with the flag option `--walk-reflogs` (or it's short form `-g`). The
+following command will list all stashes in the file history panel:
+
+```vim
+:DiffviewFileHistory -g --range=stash
+```
+
 ## Committing
 
 Creating commits from within nvim is a solved problem, and as such diffview.nvim

doc/diffview.txt

@@ -56,17 +56,32 @@ COMMANDS                                        *diffview-commands*
         {paths...} may be provided to narrow down what files are shown. If the
         `-C` flag is not defined, the git top-level is determined from the
         current buffer when possible. Otherwise it's determined from the cwd.
-        Examples:
->vim
+
+        Examples: >vim
+
+            " Diff the working tree against the index:
             :DiffviewOpen
+
+            " Diff the working tree against a specific commit:
             :DiffviewOpen HEAD~2
-            :DiffviewOpen HEAD~4..HEAD~2
             :DiffviewOpen d4a7b0d
-            :DiffviewOpen d4a7b0d^!
+
+            " Diff a commit range:
+            :DiffviewOpen HEAD~4..HEAD~2
             :DiffviewOpen d4a7b0d..519b30e
+
+            " Diff the changes introduced by a specific commit (kind of like
+            " `git show d4a7b0d`):
+            :DiffviewOpen d4a7b0d^!
+
+            " Diff HEAD against it's merge base in origin/main:
             :DiffviewOpen origin/main...HEAD
+
+            " Limit the scope to the given paths:
             :DiffviewOpen HEAD~2 -- lua/diffview plugin
-            :DiffviewOpen d4a7b0d -uno
+
+            " Hide untracked files:
+            :DiffviewOpen -uno
 <
 
                                                 *diffview-staging*
@@ -170,25 +185,44 @@ COMMANDS                                        *diffview-commands*
         <Tab>, or by using the mappings that are shown directly in the panel,
         preceding the flags' descriptions.
 
-        NOTE: Commits are only listed if git-log is able to show its file
-        stats given your currently configured log options. As such pay
-        attention to the value of `--diff-merges`, as this controls how
-        git-log treats merge commits and subsequently it's willingness to show
-        stats for these commits. Setting `--diff-merges=off` will tell git-log
-        to never compare merge commits, and as such they won't show up in the
-        file history view.
+                                                *diffview-inspect-stash*
+        The latest Git stash is always stored in the reference `refs/stash`.
+        We can find all the stashes by traversing the reflog for this
+        reference. This can be achieved with the flag option `--walk-reflogs`
+        (or it's short form `-g`). The following command will list all stashes
+        in the file history panel: >
+                :DiffviewFileHistory -g --range=stash
+<
+
+        Examples: >vim
 
-        Examples:
->vim
+            " History for the current branch:
             :DiffviewFileHistory
+
+            " History for the current file:
             :DiffviewFileHistory %
+
+            " History for a specific file:
             :DiffviewFileHistory path/to/some/file.txt
+
+            " History for a specific directory:
             :DiffviewFileHistory path/to/some/directory
+
+            " History for multiple paths:
             :DiffviewFileHistory multiple/paths foo/bar baz/qux
+
+            " Compare history against a fixed base:
             :DiffviewFileHistory --base=HEAD~4
             :DiffviewFileHistory --base=LOCAL
+
+            " History for a specific rev range:
             :DiffviewFileHistory --range=origin..HEAD
             :DiffviewFileHistory --range=feat/some-branch
+
+            " Inspect diffs for Git stashes:
+            :DiffviewFileHistory -g --range=stash
+
+            " Trace the line evolution for the current visual selection:
             :'<,'>DiffviewFileHistory
 <
 
@@ -226,6 +260,9 @@ COMMANDS                                        *diffview-commands*
         --reflog
                 Include all reachable objects mentioned by reflogs.
 
+        -g, --walk-reflogs
+                Walk reflogs instead of the commit ancestry chain.
+
         --all   Include all refs.
 
         --merges
@@ -344,7 +381,7 @@ COMMANDS                                        *diffview-commands*
                         current Diffview.
 
                                                 *:DiffviewLog*
-:DiffviewLog            Open the log.
+:DiffviewLog            Open the debug log.
 
 ==============================================================================
 
@@ -1539,6 +1576,9 @@ LogOptions                                      *diffview.git.LogOptions*
             {reflog} (boolean)
                 Include all reachable objects mentioned by reflogs.
 
+            {walk_reflogs} (boolean)
+                Walk reflogs instead of the commit ancestry chain.
+
             {all} (boolean)
                 Include all refs.
 

lua/diffview/config.lua

@@ -257,6 +257,7 @@ M._config = M.defaults
 ---@field first_parent boolean
 ---@field show_pulls boolean
 ---@field reflog boolean
+---@field walk_reflogs boolean
 ---@field all boolean
 ---@field merges boolean
 ---@field no_merges boolean
@@ -299,6 +300,7 @@ M.log_option_defaults = {
     first_parent = false,
     show_pulls = false,
     reflog = false,
+    walk_reflogs = false,
     all = false,
     merges = false,
     no_merges = false,

lua/diffview/hl.lua

@@ -448,7 +448,9 @@ M.hl_links = {
   FilePanelConflicts = "DiagnosticSignWarn",
   FolderName = "Directory",
   FolderSign = "PreProc",
+  Hash = "Identifier",
   Reference = "Function",
+  ReflogSelector = "Special",
   StatusAdded = "diffAdded",
   StatusUntracked = "diffAdded",
   StatusModified = "diffChanged",

lua/diffview/scene/views/file_history/render.lua

@@ -131,7 +131,11 @@ local function render_entries(panel, parent, entries, updating)
     end
 
     if entry.commit.hash then
-      comp:add_text(" " .. entry.commit.hash:sub(1, 8), "DiffviewSecondary")
+      comp:add_text(" " .. entry.commit.hash:sub(1, 8), "DiffviewHash")
+    end
+
+    if (entry.commit --[[@as GitCommit ]]).reflog_selector then
+      comp:add_text((" %s"):format((entry.commit --[[@as GitCommit ]]).reflog_selector), "DiffviewReflogSelector")
     end
 
     if entry.commit.ref_names then

lua/diffview/vcs/adapters/git/commit.lua

@@ -9,11 +9,14 @@ local M = {}
 
 
 ---@class GitCommit : Commit
+---@field reflog_selector? string
 local GitCommit = oop.create_class("GitCommit", Commit.__get())
 
 function GitCommit:init(opt)
   self:super(opt)
 
+  self.reflog_selector = opt.reflog_selector ~= "" and opt.reflog_selector or nil
+
   if opt.time_offset then
     self.time_offset = Commit.parse_time_offset(opt.time_offset)
     self.time = self.time - self.time_offset

lua/diffview/vcs/adapters/git/init.lua

@@ -47,9 +47,11 @@ GitAdapter.bootstrap = {
 GitAdapter.COMMIT_PRETTY_FMT = (
   "%H %P"      -- Commit hash followed by parent hashes
   .. "%n%an"   -- Author name
-  .. "%n%ad"   -- Author date
-  .. "%n%ar"   -- Author date relative
+  .. "%n%at"   -- Author date: UNIX timestamp
+  .. "%n%ai"   -- Author date: ISO (gives us timezone)
+  .. "%n%ar"   -- Author date: relative
   .. "%n..%D"  -- Ref names
+  .. "%n..%gd" -- Reflog selectors
   .. "%n..%s"  -- Subject
   -- The leading dots here are only used for padding to ensure those lines
   -- won't ever be completetely empty. This way the lines will be
@@ -388,6 +390,7 @@ function GitAdapter:prepare_fh_options(log_options, single_file)
       o.first_parent and { "--first-parent" } or nil,
       o.show_pulls and { "--show-pulls" } or nil,
       o.reflog and { "--reflog" } or nil,
+      o.walk_reflogs and { "--walk-reflogs" } or nil,
       o.all and { "--all" } or nil,
       o.merges and { "--merges" } or nil,
       o.no_merges and { "--no-merges" } or nil,
@@ -451,6 +454,7 @@ end
 ---@field time_offset string
 ---@field rel_date string
 ---@field ref_names string
+---@field reflog_selector string
 ---@field subject string
 ---@field namestat string[]
 ---@field numstat string[]
@@ -462,22 +466,23 @@ end
 ---@return GitAdapter.LogData data
 local function structure_fh_data(stat_data, keep_diff)
   local right_hash, left_hash, merge_hash = unpack(utils.str_split(stat_data[1]))
-  local time, time_offset = unpack(utils.str_split(stat_data[3]))
+  local time_offset = utils.str_split(stat_data[4])[3]
 
   ---@type GitAdapter.LogData
   local ret = {
     left_hash = left_hash ~= "" and left_hash or nil,
     right_hash = right_hash,
     merge_hash = merge_hash,
     author = stat_data[2],
-    time = tonumber(time),
+    time = tonumber(stat_data[3]),
     time_offset = time_offset,
-    rel_date = stat_data[4],
-    ref_names = stat_data[5] and stat_data[5]:sub(3) or "",
-    subject = stat_data[6] and stat_data[6]:sub(3) or "",
+    rel_date = stat_data[5],
+    ref_names = stat_data[6] and stat_data[6]:sub(3) or "",
+    reflog_selector = stat_data[7] and stat_data[7]:sub(3) or "",
+    subject = stat_data[8] and stat_data[8]:sub(3) or "",
   }
 
-  local namestat, numstat = structure_stat_data(stat_data, 7)
+  local namestat, numstat = structure_stat_data(stat_data, 9)
   ret.namestat = namestat
   ret.numstat = numstat
 
@@ -486,26 +491,21 @@ local function structure_fh_data(stat_data, keep_diff)
   end
 
   -- Soft validate the data
-  if (ret.merge_hash and (#namestat == 0 or #numstat == 0)) or #namestat ~= #numstat then
-    -- Merge commits are likely to be missing stat data depending on the value
-    -- of `--diff-merges`.
-    ret.valid = false
-  else
-    ret.valid = #stat_data >= 6 and pcall(
-      vim.validate,
-      {
-        left_hash = { ret.left_hash, "string", true },
-        right_hash = { ret.right_hash, "string" },
-        merge_hash = { ret.merge_hash, "string", true },
-        author = { ret.author, "string" },
-        time = { ret.time, "number" },
-        time_offset = { ret.time_offset, "string" },
-        rel_date = { ret.rel_date, "string" },
-        ref_names = { ret.ref_names, "string" },
-        subject = { ret.subject, "string" },
-      }
-    )
-  end
+  ret.valid = #namestat == #numstat and pcall(
+    vim.validate,
+    {
+      left_hash = { ret.left_hash, "string", true },
+      right_hash = { ret.right_hash, "string" },
+      merge_hash = { ret.merge_hash, "string", true },
+      author = { ret.author, "string" },
+      time = { ret.time, "number" },
+      time_offset = { ret.time_offset, "string" },
+      rel_date = { ret.rel_date, "string" },
+      ref_names = { ret.ref_names, "string" },
+      reflog_selector = { ret.reflog_selector, "string" },
+      subject = { ret.subject, "string" },
+    }
+  )
 
   return ret
 end
@@ -569,7 +569,6 @@ function GitAdapter:stream_fh_data(state)
       "gc.auto=0",
       "log",
       "--pretty=format:%x00%n" .. GitAdapter.COMMIT_PRETTY_FMT,
-      "--date=raw",
       "--numstat",
       "--raw",
       state.prepared_log_opts.flags,
@@ -649,7 +648,6 @@ function GitAdapter:stream_line_trace_data(state)
       "--color=never",
       "--no-ext-diff",
       "--pretty=format:%x00%n" .. GitAdapter.COMMIT_PRETTY_FMT,
-      "--date=raw",
       state.prepared_log_opts.flags,
       state.prepared_log_opts.rev_range,
       "--"
@@ -772,6 +770,7 @@ function GitAdapter:file_history_options(range, paths, argo)
     { "first-parent" },
     { "show-pulls" },
     { "reflog" },
+    { "walk-reflogs", "g" },
     { "all" },
     { "merges" },
     { "no-merges" },
@@ -985,6 +984,7 @@ GitAdapter.file_history_worker = async.void(function(self, out_stream, opt)
       time_offset = new_data.time_offset,
       rel_date = new_data.rel_date,
       ref_names = new_data.ref_names,
+      reflog_selector = new_data.reflog_selector,
       subject = new_data.subject,
       diff = new_data.diff,
     })
@@ -1028,10 +1028,9 @@ GitAdapter.fh_retry_commit = async.wrap(function(self, rev_arg, state, opt, call
       "gc.auto=0",
       "show",
       "--pretty=format:" .. GitAdapter.COMMIT_PRETTY_FMT,
-      "--date=raw",
       "--numstat",
       "--raw",
-      "--diff-merges=" .. (opt.is_merge and "first-parent" or state.log_options.diff_merges),
+      "--diff-merges=" .. state.log_options.diff_merges,
       (state.single_file and state.log_options.follow) and "--follow" or nil,
       rev_arg,
       "--",
@@ -1849,6 +1848,7 @@ GitAdapter.flags = {
     FlagOption("-p", "--first-parent", "Follow only the first parent upon seeing a merge commit"),
     FlagOption("-s", "--show-pulls", "Show merge commits the first introduced a change to a branch"),
     FlagOption("-R", "--reflog", "Include all reachable objects mentioned by reflogs"),
+    FlagOption("-g", "--walk-reflogs", "Walk reflogs instead of the commit ancestry chain"),
     FlagOption("-a", "--all", "Include all refs"),
     FlagOption("-m", "--merges", "List only merge commits"),
     FlagOption("-n", "--no-merges", "List no merge commits"),
@@ -2055,6 +2055,7 @@ function GitAdapter:init_completion()
   self.comp.file_history:put({ "--first-parent" })
   self.comp.file_history:put({ "--show-pulls" })
   self.comp.file_history:put({ "--reflog" })
+  self.comp.file_history:put({ "--walk-reflogs", "-g" })
   self.comp.file_history:put({ "--all" })
   self.comp.file_history:put({ "--merges" })
   self.comp.file_history:put({ "--no-merges" })