[rubygems/rubygems] Feature: accept pull request URLs as github source

Very often github source is used to temporarily use a modified gem
while a PR upstream is being reviewed.

So for instance https://github.com/ruby/bigdecimal/pull/211 will look like:

```ruby
gem "bigdecimal", github: "casperisfine/bigdecimal", branch: "git-gem" # https://github.com/ruby/bigdecimal/pull/200
```

It's annoying because you have to fiddle with the branch name, which is copied as `casperisfine:git-gem`, etc etc.

If I could simply use the PR URL like this:

```
gem "bigdecimal", github: "https://github.com/ruby/bigdecimal/pull/211"
```

It would make a very common task for me so much simpler.

https://github.com/rubygems/rubygems/commit/517c527751

27 files changed, 77 insertions, 28 deletions

diff --git a/lib/bundler/dsl.rb b/lib/bundler/dsl.rb
index ed7b3e2d6b..1108fc3b78 100644
--- a/lib/bundler/dsl.rb
+++ b/lib/bundler/dsl.rb
@@ -18,6 +18,8 @@ module Bundler
     VALID_KEYS = %w[group groups git path glob name branch ref tag require submodules
                     platform platforms type source install_if gemfile].freeze
 
+    GITHUB_PULL_REQUEST_URL = %r{\Ahttps://github\.com/([A-Za-z0-9_\-\.]+/[A-Za-z0-9_\-\.]+)/pull/(\d+)\z}.freeze
+
     attr_reader :gemspecs
     attr_accessor :dependencies
 
@@ -278,8 +280,17 @@ module Bundler
         warn_deprecated_git_source(:github, <<-'RUBY'.strip, 'Change any "reponame" :github sources to "username/reponame".')
 "https://github.com/#{repo_name}.git"
         RUBY
-        repo_name = "#{repo_name}/#{repo_name}" unless repo_name.include?("/")
-        "https://github.com/#{repo_name}.git"
+        if repo_name =~ GITHUB_PULL_REQUEST_URL
+          {
+            "git" => "https://github.com/#{$1}.git",
+            "branch" => "refs/pull/#{$2}/head",
+            "ref" => nil,
+            "tag" => nil,
+          }
+        else
+          repo_name = "#{repo_name}/#{repo_name}" unless repo_name.include?("/")
+          "https://github.com/#{repo_name}.git"
+        end
       end
 
       git_source(:gist) do |repo_name|
@@ -365,7 +376,11 @@ repo_name ||= user_name
 
       git_name = (git_names & opts.keys).last
       if @git_sources[git_name]
-        opts["git"] = @git_sources[git_name].call(opts[git_name])
+        git_opts = @git_sources[git_name].call(opts[git_name])
+        git_opts = { "git" => git_opts } if git_opts.is_a?(String)
+        opts.merge!(git_opts) do |key, _gemfile_value, _git_source_value|
+          raise GemfileError, %(The :#{key} option can't be used with `#{git_name}: #{opts[git_name].inspect}`)
+        end
       end
 
       %w[git path].each do |type|
diff --git a/lib/bundler/man/bundle-add.1 b/lib/bundler/man/bundle-add.1
index 1d1e32e2e5..a94467e25f 100644
--- a/lib/bundler/man/bundle-add.1
+++ b/lib/bundler/man/bundle-add.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-ADD" "1" "November 2021" "" ""
+.TH "BUNDLE\-ADD" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-add\fR \- Add gem to the Gemfile and run bundle install
diff --git a/lib/bundler/man/bundle-binstubs.1 b/lib/bundler/man/bundle-binstubs.1
index 1447c03448..6d1b1d4247 100644
--- a/lib/bundler/man/bundle-binstubs.1
+++ b/lib/bundler/man/bundle-binstubs.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-BINSTUBS" "1" "November 2021" "" ""
+.TH "BUNDLE\-BINSTUBS" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-binstubs\fR \- Install the binstubs of the listed gems
diff --git a/lib/bundler/man/bundle-cache.1 b/lib/bundler/man/bundle-cache.1
index b774bfd39b..acbdae0df2 100644
--- a/lib/bundler/man/bundle-cache.1
+++ b/lib/bundler/man/bundle-cache.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-CACHE" "1" "November 2021" "" ""
+.TH "BUNDLE\-CACHE" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-cache\fR \- Package your needed \fB\.gem\fR files into your application
diff --git a/lib/bundler/man/bundle-check.1 b/lib/bundler/man/bundle-check.1
index 1d490ca2ba..e555c9b399 100644
--- a/lib/bundler/man/bundle-check.1
+++ b/lib/bundler/man/bundle-check.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-CHECK" "1" "November 2021" "" ""
+.TH "BUNDLE\-CHECK" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-check\fR \- Verifies if dependencies are satisfied by installed gems
diff --git a/lib/bundler/man/bundle-clean.1 b/lib/bundler/man/bundle-clean.1
index db13ad2bf5..d403247524 100644
--- a/lib/bundler/man/bundle-clean.1
+++ b/lib/bundler/man/bundle-clean.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-CLEAN" "1" "November 2021" "" ""
+.TH "BUNDLE\-CLEAN" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-clean\fR \- Cleans up unused gems in your bundler directory
diff --git a/lib/bundler/man/bundle-config.1 b/lib/bundler/man/bundle-config.1
index 94f7b98d9a..5c07e227fd 100644
--- a/lib/bundler/man/bundle-config.1
+++ b/lib/bundler/man/bundle-config.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-CONFIG" "1" "November 2021" "" ""
+.TH "BUNDLE\-CONFIG" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-config\fR \- Set bundler configuration options
diff --git a/lib/bundler/man/bundle-doctor.1 b/lib/bundler/man/bundle-doctor.1
index 64ae8d1164..87a7fe5f2f 100644
--- a/lib/bundler/man/bundle-doctor.1
+++ b/lib/bundler/man/bundle-doctor.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-DOCTOR" "1" "November 2021" "" ""
+.TH "BUNDLE\-DOCTOR" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-doctor\fR \- Checks the bundle for common problems
diff --git a/lib/bundler/man/bundle-exec.1 b/lib/bundler/man/bundle-exec.1
index 61b9833c35..69adfa7c92 100644
--- a/lib/bundler/man/bundle-exec.1
+++ b/lib/bundler/man/bundle-exec.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-EXEC" "1" "November 2021" "" ""
+.TH "BUNDLE\-EXEC" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-exec\fR \- Execute a command in the context of the bundle
diff --git a/lib/bundler/man/bundle-gem.1 b/lib/bundler/man/bundle-gem.1
index 42875fc189..fae5c34e7e 100644
--- a/lib/bundler/man/bundle-gem.1
+++ b/lib/bundler/man/bundle-gem.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-GEM" "1" "November 2021" "" ""
+.TH "BUNDLE\-GEM" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-gem\fR \- Generate a project skeleton for creating a rubygem
diff --git a/lib/bundler/man/bundle-info.1 b/lib/bundler/man/bundle-info.1
index 0804534c3e..9e1400ec56 100644
--- a/lib/bundler/man/bundle-info.1
+++ b/lib/bundler/man/bundle-info.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-INFO" "1" "November 2021" "" ""
+.TH "BUNDLE\-INFO" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-info\fR \- Show information for the given gem in your bundle
diff --git a/lib/bundler/man/bundle-init.1 b/lib/bundler/man/bundle-init.1
index 3171452cff..612d16031c 100644
--- a/lib/bundler/man/bundle-init.1
+++ b/lib/bundler/man/bundle-init.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-INIT" "1" "November 2021" "" ""
+.TH "BUNDLE\-INIT" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-init\fR \- Generates a Gemfile into the current working directory
diff --git a/lib/bundler/man/bundle-inject.1 b/lib/bundler/man/bundle-inject.1
index 647f71a444..ded4d6d64b 100644
--- a/lib/bundler/man/bundle-inject.1
+++ b/lib/bundler/man/bundle-inject.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-INJECT" "1" "November 2021" "" ""
+.TH "BUNDLE\-INJECT" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-inject\fR \- Add named gem(s) with version requirements to Gemfile
diff --git a/lib/bundler/man/bundle-install.1 b/lib/bundler/man/bundle-install.1
index 51d70468f7..6824dea3b0 100644
--- a/lib/bundler/man/bundle-install.1
+++ b/lib/bundler/man/bundle-install.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-INSTALL" "1" "November 2021" "" ""
+.TH "BUNDLE\-INSTALL" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-install\fR \- Install the dependencies specified in your Gemfile
diff --git a/lib/bundler/man/bundle-list.1 b/lib/bundler/man/bundle-list.1
index 3aba56cf0b..a697173af9 100644
--- a/lib/bundler/man/bundle-list.1
+++ b/lib/bundler/man/bundle-list.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-LIST" "1" "November 2021" "" ""
+.TH "BUNDLE\-LIST" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-list\fR \- List all the gems in the bundle
diff --git a/lib/bundler/man/bundle-lock.1 b/lib/bundler/man/bundle-lock.1
index acd4a8b7be..ef515b0337 100644
--- a/lib/bundler/man/bundle-lock.1
+++ b/lib/bundler/man/bundle-lock.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-LOCK" "1" "November 2021" "" ""
+.TH "BUNDLE\-LOCK" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-lock\fR \- Creates / Updates a lockfile without installing
diff --git a/lib/bundler/man/bundle-open.1 b/lib/bundler/man/bundle-open.1
index 1dfa14d4c1..dd28566bdb 100644
--- a/lib/bundler/man/bundle-open.1
+++ b/lib/bundler/man/bundle-open.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-OPEN" "1" "November 2021" "" ""
+.TH "BUNDLE\-OPEN" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-open\fR \- Opens the source directory for a gem in your bundle
diff --git a/lib/bundler/man/bundle-outdated.1 b/lib/bundler/man/bundle-outdated.1
index 1b5bf66853..b9d50a1c71 100644
--- a/lib/bundler/man/bundle-outdated.1
+++ b/lib/bundler/man/bundle-outdated.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-OUTDATED" "1" "November 2021" "" ""
+.TH "BUNDLE\-OUTDATED" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-outdated\fR \- List installed gems with newer versions available
diff --git a/lib/bundler/man/bundle-platform.1 b/lib/bundler/man/bundle-platform.1
index a62091625c..b1c859f64b 100644
--- a/lib/bundler/man/bundle-platform.1
+++ b/lib/bundler/man/bundle-platform.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-PLATFORM" "1" "November 2021" "" ""
+.TH "BUNDLE\-PLATFORM" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-platform\fR \- Displays platform compatibility information
diff --git a/lib/bundler/man/bundle-pristine.1 b/lib/bundler/man/bundle-pristine.1
index 52d5b6a3aa..6e4a028666 100644
--- a/lib/bundler/man/bundle-pristine.1
+++ b/lib/bundler/man/bundle-pristine.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-PRISTINE" "1" "November 2021" "" ""
+.TH "BUNDLE\-PRISTINE" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-pristine\fR \- Restores installed gems to their pristine condition
diff --git a/lib/bundler/man/bundle-remove.1 b/lib/bundler/man/bundle-remove.1
index 1b960fe429..0b4edd1414 100644
--- a/lib/bundler/man/bundle-remove.1
+++ b/lib/bundler/man/bundle-remove.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-REMOVE" "1" "November 2021" "" ""
+.TH "BUNDLE\-REMOVE" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-remove\fR \- Removes gems from the Gemfile
diff --git a/lib/bundler/man/bundle-show.1 b/lib/bundler/man/bundle-show.1
index 733161318f..375699ddf0 100644
--- a/lib/bundler/man/bundle-show.1
+++ b/lib/bundler/man/bundle-show.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-SHOW" "1" "November 2021" "" ""
+.TH "BUNDLE\-SHOW" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-show\fR \- Shows all the gems in your bundle, or the path to a gem
diff --git a/lib/bundler/man/bundle-update.1 b/lib/bundler/man/bundle-update.1
index 85916e9a9e..f5a79fe24e 100644
--- a/lib/bundler/man/bundle-update.1
+++ b/lib/bundler/man/bundle-update.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-UPDATE" "1" "November 2021" "" ""
+.TH "BUNDLE\-UPDATE" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-update\fR \- Update your gems to the latest available versions
diff --git a/lib/bundler/man/bundle-viz.1 b/lib/bundler/man/bundle-viz.1
index 742d30cd31..f792aa6346 100644
--- a/lib/bundler/man/bundle-viz.1
+++ b/lib/bundler/man/bundle-viz.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-VIZ" "1" "November 2021" "" ""
+.TH "BUNDLE\-VIZ" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\-viz\fR \- Generates a visual dependency graph for your Gemfile
diff --git a/lib/bundler/man/bundle.1 b/lib/bundler/man/bundle.1
index 4f4bf6b0b9..b1458bf57b 100644
--- a/lib/bundler/man/bundle.1
+++ b/lib/bundler/man/bundle.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE" "1" "November 2021" "" ""
+.TH "BUNDLE" "1" "December 2021" "" ""
 .
 .SH "NAME"
 \fBbundle\fR \- Ruby Dependency Management
diff --git a/lib/bundler/man/gemfile.5 b/lib/bundler/man/gemfile.5
index 90fb67a3c7..1ac003a780 100644
--- a/lib/bundler/man/gemfile.5
+++ b/lib/bundler/man/gemfile.5
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "GEMFILE" "5" "November 2021" "" ""
+.TH "GEMFILE" "5" "December 2021" "" ""
 .
 .SH "NAME"
 \fBGemfile\fR \- A format for describing gem dependencies for Ruby programs
@@ -506,6 +506,32 @@ gem "rails", :git => "git://github\.com/rails/rails\.git"
 .P
 Since the \fBgithub\fR method is a specialization of \fBgit_source\fR, it accepts a \fB:branch\fR named argument\.
 .
+.P
+You can also directly pass a pull request URL:
+.
+.IP "" 4
+.
+.nf
+
+gem "rails", :github => "https://github\.com/rails/rails/pull/43753"
+.
+.fi
+.
+.IP "" 0
+.
+.P
+Which is equivalent to:
+.
+.IP "" 4
+.
+.nf
+
+gem "rails", :github => "rails/rails", branch: "refs/pull/43753/head"
+.
+.fi
+.
+.IP "" 0
+.
 .SS "GIST"
 If the git repository you want to use is hosted as a GitHub Gist and is public, you can use the :gist shorthand to specify the gist identifier (without the trailing "\.git")\.
 .
diff --git a/lib/bundler/man/gemfile.5.ronn b/lib/bundler/man/gemfile.5.ronn
index ea7cf40e63..0feaf58246 100644
--- a/lib/bundler/man/gemfile.5.ronn
+++ b/lib/bundler/man/gemfile.5.ronn
@@ -372,6 +372,14 @@ Are both equivalent to
 
 Since the `github` method is a specialization of `git_source`, it accepts a `:branch` named argument.
 
+You can also directly pass a pull request URL:
+
+    gem "rails", :github => "https://github.com/rails/rails/pull/43753"
+
+Which is equivalent to:
+
+    gem "rails", :github => "rails/rails", branch: "refs/pull/43753/head"
+
 ### GIST
 
 If the git repository you want to use is hosted as a GitHub Gist and is public, you can use