Remove magit-libgit.el

This is just a proof-of-concept.  Until that changes its dead weight
that should not be packaged.  Removing it from version control is the
only way to prevent it from getting packaged anyway.

8 files changed, 7 insertions, 158 deletions

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 6f3c7f1..01d105e 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -1,7 +1,5 @@
 name: Test
 on: [push, pull_request]
-env:
-  BUILD_MAGIT_LIBGIT: "false"
 jobs:
   test:
     name: Test
diff --git a/default.mk b/default.mk
index 6a50e28..2c3cc37 100644
--- a/default.mk
+++ b/default.mk
@@ -40,8 +40,6 @@ GITSTATS_DIR  ?= $(TOP)docs/stats
 GITSTATS_ARGS ?= -c style=https://magit.vc/assets/stats.css \
                  -c max_authors=180 -c graph_max_authors=7
 
-BUILD_MAGIT_LIBGIT ?= false
-
 ## Files #############################################################
 
 PKG       = magit
@@ -57,9 +55,6 @@ EPUBFILES = $(addsuffix .epub,$(filter-out git-commit,$(PACKAGES)))
 ELS  = git-commit.el
 ELS += magit-section.el
 ELS += magit-base.el
-ifeq "$(BUILD_MAGIT_LIBGIT)" "true"
-ELS += magit-libgit.el
-endif
 ELS += magit-git.el
 ELS += magit-mode.el
 ELS += magit-margin.el
@@ -171,13 +166,6 @@ ifeq "$(DASH_DIR)" ""
   DASH_DIR = $(TOP)../dash
 endif
 
-LIBGIT_DIR ?= $(shell \
-  find -L $(ELPA_DIR) -maxdepth 1 -regex '.*/libgit-[.0-9]*' 2> /dev/null | \
-  sort | tail -n 1)
-ifeq "$(LIBGIT_DIR)" ""
-  LIBGIT_DIR = $(TOP)../libgit
-endif
-
 SEQ_DIR ?= $(shell \
   find -L $(ELPA_DIR) -maxdepth 1 -regex '.*/seq-[.0-9]*' 2> /dev/null | \
   sort | tail -n 1)
@@ -218,7 +206,6 @@ LOAD_PATH = -L $(TOP)lisp
 ifdef CYGPATH
   LOAD_PATH += -L $(shell cygpath --mixed $(COMPAT_DIR))
   LOAD_PATH += -L $(shell cygpath --mixed $(DASH_DIR))
-  LOAD_PATH += -L $(shell cygpath --mixed $(LIBGIT_DIR))
   LOAD_PATH += -L $(shell cygpath --mixed $(SEQ_DIR))
   LOAD_PATH += -L $(shell cygpath --mixed $(TRANSIENT_DIR))
   LOAD_PATH += -L $(shell cygpath --mixed $(WITH_EDITOR_DIR))
@@ -228,7 +215,6 @@ ifdef CYGPATH
 else
   LOAD_PATH += -L $(COMPAT_DIR)
   LOAD_PATH += -L $(DASH_DIR)
-  LOAD_PATH += -L $(LIBGIT_DIR)
   LOAD_PATH += -L $(SEQ_DIR)
   LOAD_PATH += -L $(TRANSIENT_DIR)
   LOAD_PATH += -L $(WITH_EDITOR_DIR)
diff --git a/lisp/Makefile b/lisp/Makefile
index 0f7f52d..9a16e39 100644
--- a/lisp/Makefile
+++ b/lisp/Makefile
@@ -12,12 +12,7 @@ all: lisp
 git-commit.elc:
 magit-section.elc:
 magit-base.elc:            magit-section.elc
-ifeq "$(BUILD_MAGIT_LIBGIT)" "true"
-magit-libgit.elc:
-magit-git.elc:             magit-base.elc magit-libgit.elc
-else
 magit-git.elc:             magit-base.elc
-endif
 magit-mode.elc:            magit-base.elc magit-git.elc
 magit-margin.elc:          magit-base.elc magit-mode.elc
 magit-process.elc:         magit-base.elc magit-git.elc magit-mode.elc
diff --git a/lisp/magit-base.el b/lisp/magit-base.el
index 7c71870..c7bc75c 100644
--- a/lisp/magit-base.el
+++ b/lisp/magit-base.el
@@ -861,16 +861,12 @@ See info node `(magit)Debugging Tools' for more information."
                    (delete-dups
                     (cl-mapcan
                      (lambda (lib)
-                       (let ((path (locate-library lib)))
-                         (cond
-                          (path
-                           (list (file-name-directory path)))
-                          ((not (equal lib "libgit"))
-                           (error "Cannot find mandatory dependency %s" lib)))))
+                       (if-let ((path (locate-library lib)))
+                           (list (file-name-directory path))
+                         (error "Cannot find mandatory dependency %s" lib)))
                      '(;; Like `LOAD_PATH' in `default.mk'.
                        "compat"
                        "dash"
-                       "libgit"
                        "transient"
                        "with-editor"
                        ;; Obviously `magit' itself is needed too.
diff --git a/lisp/magit-core.el b/lisp/magit-core.el
index ff15486..57b08f4 100644
--- a/lisp/magit-core.el
+++ b/lisp/magit-core.el
@@ -37,15 +37,6 @@
 (require 'magit-transient)
 (require 'magit-autorevert)
 
-(when (and (not magit-inhibit-libgit)
-           (magit--libgit-available-p))
-  (condition-case err
-      (require 'magit-libgit)
-    (error
-     (setq magit-inhibit-libgit 'error)
-     (message "Error while loading `magit-libgit': %S" err)
-     (message "That is not fatal.  The `libegit2' module just won't be used."))))
-
 ;;; Options
 
 (defgroup magit nil
diff --git a/lisp/magit-git.el b/lisp/magit-git.el
index 16c8b22..d1785d7 100644
--- a/lisp/magit-git.el
+++ b/lisp/magit-git.el
@@ -65,41 +65,6 @@
   (cl-pushnew 'orig-rev eieio--known-slot-names)
   (cl-pushnew 'number eieio--known-slot-names))
 
-;;; Git implementations
-
-(defvar magit-inhibit-libgit t
-  "Whether to inhibit the use of libgit.
-Use of libgit is inhibited by default because support for libgit
-in magit is only a stub for now.  There is no benefit in using
-it.")
-
-(defvar magit--libgit-available-p 'unknown
-  "Whether libgit is available.
-Use the function by the same name instead of this variable.")
-
-(defun magit--libgit-available-p ()
-  (if (eq magit--libgit-available-p 'unknown)
-      (setq magit--libgit-available-p
-            (and module-file-suffix
-                 (let ((libgit (locate-library "libgit")))
-                   (and libgit
-                        (or (locate-library "libegit2")
-                            (let ((load-path
-                                   (cons (expand-file-name
-                                          (convert-standard-filename "build")
-                                          (file-name-directory libgit))
-                                         load-path)))
-                              (locate-library "libegit2")))))))
-    magit--libgit-available-p))
-
-(defun magit-gitimpl ()
-  "Return the Git implementation used in this repository."
-  (if (and (not magit-inhibit-libgit)
-           (not (file-remote-p default-directory))
-           (magit--libgit-available-p))
-      'libgit
-    'git))
-
 ;;; Options
 
 ;; For now this is shared between `magit-process' and `magit-git'.
diff --git a/lisp/magit-libgit.el b/lisp/magit-libgit.el
deleted file mode 100644
index 6db1094..0000000
--- a/lisp/magit-libgit.el
+++ /dev/null
@@ -1,81 +0,0 @@
-;;; magit-libgit.el --- (POC) Teach Magit to use Libgit2  -*- lexical-binding:t -*-
-
-;; Copyright (C) 2008-2024 The Magit Project Contributors
-
-;; Author: Jonas Bernoulli <emacs.magit@jonas.bernoulli.dev>
-;; Maintainer: Jonas Bernoulli <emacs.magit@jonas.bernoulli.dev>
-
-;; SPDX-License-Identifier: GPL-3.0-or-later
-
-;; Magit is free software: you can redistribute it and/or modify
-;; it under the terms of the GNU General Public License as published
-;; by the Free Software Foundation, either version 3 of the License,
-;; or (at your option) any later version.
-;;
-;; Magit is distributed in the hope that it will be useful,
-;; but WITHOUT ANY WARRANTY; without even the implied warranty of
-;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-;; GNU General Public License for more details.
-;;
-;; You should have received a copy of the GNU General Public License
-;; along with Magit.  If not, see <https://www.gnu.org/licenses/>.
-
-;; You should have received a copy of the AUTHORS.md file, which
-;; lists all contributors.  If not, see https://magit.vc/authors.
-
-;;; Commentary:
-
-;; This library is not used by default and it is highly experimental.
-;; It only implements a single method.  Do not use this.
-
-;; This library teaches Magit to use functions provided by the
-;; `libegit2' module to perform certain tasks.  That module used the
-;; Libgit2 implementation of the Git core methods and is implemented
-;; in the `libgit' package.
-
-;; The hope is that using a C module instead of calling out to `git'
-;; all the time increases performance; especially on Windows where
-;; starting a process is unreasonably slow.
-
-;;; Code:
-
-(require 'cl-lib)
-(require 'compat)
-(require 'dash)
-(require 'eieio)
-(require 'subr-x)
-
-(when (and (featurep 'seq)
-           (not (fboundp 'seq-keep)))
-  (unload-feature 'seq 'force))
-(require 'seq)
-
-(require 'magit-git)
-
-(require 'libgit)
-
-;;; Utilities
-
-(defun magit-libgit-repo (&optional directory)
-  "Return an object for the repository in DIRECTORY.
-If optional DIRECTORY is nil, then use `default-directory'."
-  (and-let* ((default-directory
-              (let ((magit-inhibit-libgit t))
-                (magit-gitdir directory))))
-    (magit--with-refresh-cache
-        (cons default-directory 'magit-libgit-repo)
-      (libgit-repository-open default-directory))))
-
-;;; Methods
-
-(cl-defmethod magit-bare-repo-p
-  (&context ((magit-gitimpl) (eql libgit)) &optional noerror)
-  (and (magit--assert-default-directory noerror)
-       (if-let ((repo (magit-libgit-repo)))
-           (libgit-repository-bare-p repo)
-         (unless noerror
-           (signal 'magit-outside-git-repo default-directory)))))
-
-;;; _
-(provide 'magit-libgit)
-;;; magit-libgit.el ends here
diff --git a/lisp/magit-mode.el b/lisp/magit-mode.el
index 4c4465e..2547505 100644
--- a/lisp/magit-mode.el
+++ b/lisp/magit-mode.el
@@ -1412,9 +1412,9 @@ repositories."
   "Zap caches for the current repository.
 
 Remove the repository's entry from `magit-repository-local-cache',
-remove the host's entry from `magit--host-git-version-cache', set
-`magit-section-visibility-cache' to nil for all Magit buffers of
-the repository and set `magit--libgit-available-p' to `unknown'.
+remove the host's entry from `magit--host-git-version-cache', and
+set `magit-section-visibility-cache' to nil for all Magit buffers
+of the repository.
 
 With a prefix argument or if optional ALL is non-nil, discard the
 mentioned caches completely."
@@ -1438,8 +1438,7 @@ mentioned caches completely."
                             :key #'car :test #'equal)))
          (dolist (buffer (magit-mode-get-buffers))
            (with-current-buffer buffer
-             (setq magit-section-visibility-cache nil)))))
-  (setq magit--libgit-available-p 'unknown))
+             (setq magit-section-visibility-cache nil))))))
 
 ;;; Utilities