1 files changed, 89 insertions, 0 deletions
diff --git a/importer_bundler_extensions.rb b/importer_bundler_extensions.rb
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+++ b/importer_bundler_extensions.rb
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+#!/usr/bin/env ruby
+#
+# Extensions to Bundler library which allow using it in importers.
+#
+# Copyright (C) 2014  Codethink Limited
+#
+# This program 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; version 2 of the License.
+#
+# This program 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 this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+require 'bundler'
+
+class << Bundler
+  def default_gemfile
+    # This is a hack to make things not crash when there's no Gemfile
+    Pathname.new('.')
+  end
+end
+
+module Importer
+  module BundlerExtensions
+    def create_bundler_definition_for_gemspec(gem_name)
+      # Using the real Gemfile doesn't get great results, because people can put
+      # lots of stuff in there that is handy for developers to have but
+      # irrelevant if you just want to produce a .gem. Also, there is only one
+      # Gemfile per repo, but a repo may include multiple .gemspecs that we want
+      # to process individually. Also, some projects don't use Bundler and may
+      # not have a Gemfile at all.
+      #
+      # Instead of reading the real Gemfile, invent one that simply includes the
+      # chosen .gemspec. If present, the Gemfile.lock will be honoured.
+      fake_gemfile = Bundler::Dsl.new
+      fake_gemfile.source('https://rubygems.org')
+      begin
+        fake_gemfile.gemspec({:name => gem_name})
+      rescue Bundler::InvalidOption
+        error "Did not find #{gem_name}.gemspec in current directory."
+        exit 1
+      end
+
+      fake_gemfile.to_definition('Gemfile.lock', true)
+    end
+
+    def get_spec_for_gem(specs, gem_name)
+      found = specs[gem_name].select {|s| Gem::Platform.match(s.platform)}
+      if found.empty?
+        raise Exception,
+          "No Gemspecs found matching '#{gem_name}'"
+      elsif found.length != 1
+        raise Exception,
+          "Unsure which Gem to use for #{gem_name}, got #{found}"
+      end
+      found[0]
+    end
+
+    def spec_is_from_current_source_tree(spec, source_dir)
+      Dir.chdir(source_dir) do
+        spec.source.instance_of? Bundler::Source::Path and
+          File.identical?(spec.source.path, '.')
+      end
+    end
+
+    def validate_spec(spec, source_dir_name, expected_version)
+      if not spec_is_from_current_source_tree(spec, source_dir_name)
+        error "Specified gem '#{spec.name}' doesn't live in the source in " +
+              "'#{source_dir_name}'"
+        log.debug "SPEC: #{spec.inspect} #{spec.source}"
+        exit 1
+      end
+
+      if expected_version != nil && spec.version != expected_version
+        # This check is brought to you by Coderay, which changes its version
+        # number based on an environment variable. Other Gems may do this too.
+        error "Source in #{source_dir_name} produces #{spec.full_name}, but " +
+              "the expected version was #{expected_version}."
+        exit 1
+      end
+    end
+  end
+end