Drop bundled libgit2 (#463)

* Drop the bundled libgit2 source code

* github-action: run on all branches

* Update build configuration script

* Remove unused 'src/Makevars_libgit2.in'

* Update cleanup script

* Remove outdated CONTRIBUTING.md

* Remove unused figure/git2r-design.png

* Update README

* Remove unused patches

.Rbuildignore

@@ -2,13 +2,9 @@
 ^LICENSE$
 ^aclocal\.m4$
 ^Makefile$
-^README\.Rmd$
-^figure$
 ^man-roxygen$
-^patches$
 ^revdep$
 ^scripts$
-^CONTRIBUTING.md$
 ^tools/README\.md$
 ^.*\.Rproj$
 ^\.Rproj\.user$

.github/workflows/R-CMD-check.yaml

@@ -1,10 +1,6 @@
 # Workflow derived from https://github.com/r-lib/actions/tree/v2/examples
 # Need help debugging build failures? Start at https://github.com/r-lib/actions#where-to-find-help
-on:
-  push:
-    branches: [main, master]
-  pull_request:
-    branches: [main, master]
+on: [push, pull_request]
 
 name: R-CMD-check
 

DESCRIPTION

@@ -22,12 +22,7 @@ Suggests:
 Type: Package
 Biarch: true
 NeedsCompilation: yes
-SystemRequirements: By default, git2r uses a system installation of
-    the libgit2 headers and library. However, if a system installation
-    is not available, builds and uses a bundled version of the libgit2
-    source. zlib headers and library. OpenSSL headers and library
-    (non-macOS). LibSSH2 (optional on non-Windows) to enable the SSH
-    transport.
+SystemRequirements: libgit2 (>= 0.26)
 Collate:
     'blame.R'
     'blob.R'

Makefile

@@ -113,59 +113,6 @@ test_objects = $(wildcard tests/*.R)
 valgrind:
 	$(foreach var,$(test_objects),R -d "valgrind --tool=memcheck --leak-check=full" --vanilla < $(var);)
 
-# Sync git2r with changes in the libgit2 C-library
-#
-# 1) clone or pull libgit2 to parent directory from
-# https://github.com/libgit/libgit.git
-#
-# 2) run 'make sync_libgit2'. It first removes files and then copy
-# files from libgit2 directory. Next it runs an R script to build
-# Makevars.in and Makevars.win based on source files. Finally it runs
-# a patch command to change some lines in the source code to pass
-# 'R CMD check git2r'
-#
-# 3) Build and check updated package 'make check'
-sync_libgit2:
-	-rm -f src/libgit2/deps/http-parser/*
-	-rm -f src/libgit2/deps/xdiff/*
-	-rm -rf src/libgit2/include
-	-rm -rf src/libgit2/src
-	-cp -f ../libgit2/deps/http-parser/* src/libgit2/deps/http-parser
-	-cp -f ../libgit2/deps/xdiff/* src/libgit2/deps/xdiff
-	-cp -r ../libgit2/include/ src/libgit2/include
-	-rm -f src/libgit2/include/git2/inttypes.h
-	-rm -f src/libgit2/include/git2/stdint.h
-	-cp -r ../libgit2/src/ src/libgit2/src
-	-rm -rf src/libgit2/src/cli
-	-rm -f src/libgit2/deps/http-parser/CMakeLists.txt
-	-rm -f src/libgit2/deps/regex/CMakeLists.txt
-	-rm -f src/libgit2/deps/xdiff/CMakeLists.txt
-	-rm -f src/libgit2/src/README.md
-	-rm -f src/libgit2/src/CMakeLists.txt
-	-rm -f src/libgit2/src/libgit2/CMakeLists.txt
-	-rm -f src/libgit2/src/libgit2/experimental.h.in
-	-rm -f src/libgit2/src/libgit2/git2.rc
-	-rm -f src/libgit2/src/util/CMakeLists.txt
-	-rm -f src/libgit2/src/util/git2_features.h.in
-	-rm -f src/libgit2/src/stransport_stream.c
-	-rm -f src/libgit2/src/util/hash/builtin.c
-	-rm -f src/libgit2/src/util/hash/builtin.h
-	-rm -f src/libgit2/src/util/hash/common_crypto.c
-	-rm -f src/libgit2/src/util/hash/common_crypto.h
-	-rm -f src/libgit2/src/util/hash/sha1/generic.c
-	-rm -f src/libgit2/src/util/hash/sha1/generic.h
-	-rm -f src/libgit2/src/util/hash/mbedtls.c
-	-rm -f src/libgit2/src/util/hash/mbedtls.h
-	-rm -f src/libgit2/src/util/hash/win32.c
-	-rm -f src/libgit2/src/util/hash/win32.h
-	-rm -rf src/libgit2/src/util/hash/rfc6234
-	-rm -f src/libgit2/src/libgit2/transports/auth_negotiate.c
-	-rm -rf src/libgit2/src/util/win32
-	Rscript scripts/build_Makevars.R
-
-Makevars:
-	Rscript scripts/build_Makevars.R
-
 configure: configure.ac
 	autoconf ./configure.ac > ./configure
 	chmod +x ./configure

README.md

@@ -26,19 +26,11 @@ To install the development version of `git2r`, it's easiest to use the
 devtools package:
 
 ```coffee
-# install.packages("devtools")
-library(devtools)
+# install.packages("remotes")
+library(remotes)
 install_github("ropensci/git2r")
 ```
 
-Another alternative is to use `git` and `make`
-
-```coffee
-$ git clone https://github.com/ropensci/git2r.git
-$ cd git2r
-$ make install
-```
-
 ## Usage
 
 ### Repository
@@ -299,20 +291,9 @@ commit(repo, "Commit message")
 #> Summary: Commit message
 ```
 
-# Included software
-
-- The C library [libgit2](https://github.com/libgit2/libgit2). See
-  `inst/AUTHORS` for the authors of libgit2.
-
-- The libgit2 library has been modified, e.g. to use the R printing
-  and error routines, and to use `runif` instead of `rand`.
-
 # License
 
-The `git2r` package is licensed under the GPLv2. See these files for additional details:
-
-- LICENSE      - `git2r` package license (GPLv2)
-- inst/COPYING - Copyright notices for additional included software
+The `git2r` package is licensed under the GPLv2.
 
 ---
 

cleanup

@@ -1,19 +1,7 @@
 #!/bin/sh
 
 rm -f config.*
-rm -f confdefs.h
 rm -f src/Makevars
 rm -rf autom4te.cache
 rm -f src/*.o
 rm -f src/*.so
-rm -f src/libmygit.a
-rm -f src/libgit2/deps/http-parser/*.o
-rm -f src/libgit2/deps/regex/*.o
-rm -f src/libgit2/deps/xdiff/*.o
-rm -f src/libgit2/src/libgit2/*.o
-rm -f src/libgit2/src/libgit2/streams/*.o
-rm -f src/libgit2/src/libgit2/transports/*.o
-rm -f src/libgit2/src/util/*.o
-rm -f src/libgit2/src/util/allocators/*.o
-rm -f src/libgit2/src/util/hash/*.o
-rm -f src/libgit2/src/util/unix/*.o