git-branchless: backport support for libgit2 1.7

Signed-off-by: Michael Cho <michael@michaelcho.dev>

Author: cho-m

Formula/g/git-branchless.rb

@@ -1,14 +1,21 @@
 class GitBranchless < Formula
   desc "High-velocity, monorepo-scale workflow for Git"
   homepage "https://github.com/arxanas/git-branchless"
-  # TODO: check if we can use unversioned `libgit2` at version bump.
-  # See comments below for details.
-  url "https://github.com/arxanas/git-branchless/archive/refs/tags/v0.8.0.tar.gz"
-  sha256 "f9e13d9a3de960b32fb684a59492defd812bb0785df48facc964478f675f0355"
   license any_of: ["Apache-2.0", "MIT"]
   revision 1
   head "https://github.com/arxanas/git-branchless.git", branch: "master"
 
+  stable do
+    url "https://github.com/arxanas/git-branchless/archive/refs/tags/v0.8.0.tar.gz"
+    sha256 "f9e13d9a3de960b32fb684a59492defd812bb0785df48facc964478f675f0355"
+
+    # Backport support for libgit2 1.7
+    patch do
+      url "https://github.com/arxanas/git-branchless/commit/5b3d67b20e7fb910be46ea3ee9d0642d11932681.patch?full_index=1"
+      sha256 "ff81ca9c921fc6b8254a75fecec3fc606f168215f66eb658803097b6bb2fcdb8"
+    end
+  end
+
   # Upstream appears to use GitHub releases to indicate that a version is
   # released (and some tagged versions don't end up as a release), so it's
   # necessary to check release versions instead of tags.
@@ -29,15 +36,10 @@ class GitBranchless < Formula
 
   depends_on "pkg-config" => :build
   depends_on "rust" => :build
-  # To check for `libgit2` version:
-  # 1. Search for `libgit2-sys` version at https://github.com/arxanas/git-branchless/blob/v#{version}/Cargo.lock
-  # 2. If the version suffix of `libgit2-sys` is newer than +1.6.*, then:
-  #    - Migrate to the corresponding `libgit2` formula.
-  #    - Change the `LIBGIT2_SYS_USE_PKG_CONFIG` env var below to `LIBGIT2_NO_VENDOR`.
-  #      See: https://github.com/rust-lang/git2-rs/commit/59a81cac9ada22b5ea6ca2841f5bd1229f1dd659.
-  depends_on "libgit2@1.6"
+  depends_on "libgit2"
 
   def install
+    ENV["LIBGIT2_NO_VENDOR"] = "1"
     # make sure git can find git-branchless
     ENV.prepend_path "PATH", bin
 
@@ -58,7 +60,7 @@ def install
     linkage_with_libgit2 = (bin/"git-branchless").dynamically_linked_libraries.any? do |dll|
       next false unless dll.start_with?(HOMEBREW_PREFIX.to_s)
 
-      File.realpath(dll) == (Formula["libgit2@1.6"].opt_lib/shared_library("libgit2")).realpath.to_s
+      File.realpath(dll) == (Formula["libgit2"].opt_lib/shared_library("libgit2")).realpath.to_s
     end
 
     assert linkage_with_libgit2, "No linkage with libgit2! Cargo is likely using a vendored version."