From 40691aec3e0d3ec1c18a8b9630d57f11d633597f Mon Sep 17 00:00:00 2001
From: Kentaro Hayashi <kenhys@gmail.com>
Date: Wed, 31 Mar 2021 13:50:07 +0900
Subject: [PATCH] Follow depended gem version by fluent-plugin-generate

In the previous versions, generated .gemspec doesn't follow
depended gem version which is used in fluentd.gemspec at all.

Instead, it is changed to retrieve depended gem version from
Gemfile.lock to sync with it.

Before:

  spec.add_development_dependency "bundler", "~> 1.14"
  spec.add_development_dependency "rake", "~> 12.0"
  spec.add_development_dependency "test-unit", "~> 3.0"

It is required to update manually.

After:

  spec.add_development_dependency "bundler", "~> 2.2.15"
  spec.add_development_dependency "rake", "~> 13.0"
  spec.add_development_dependency "test-unit", "~> 3.3"

Above depended version is replaced by <%= %> in template.
No need to update manually.

Signed-off-by: Kentaro Hayashi <kenhys@gmail.com>
---
 lib/fluent/command/plugin_generator.rb      | 30 +++++++++++++++++++++
 templates/new_gem/fluent-plugin.gemspec.erb |  6 ++---
 2 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/lib/fluent/command/plugin_generator.rb b/lib/fluent/command/plugin_generator.rb
index 177431054b..725749e990 100644
--- a/lib/fluent/command/plugin_generator.rb
+++ b/lib/fluent/command/plugin_generator.rb
@@ -151,6 +151,36 @@ def plugin_name
     underscore_name
   end
 
+  def gem_file_path
+    File.expand_path(File.join(File.dirname(__FILE__),
+                               "../../../",
+                               "Gemfile"))
+  end
+
+  def lock_file_path
+    File.expand_path(File.join(File.dirname(__FILE__),
+                               "../../../",
+                               "Gemfile.lock"))
+  end
+
+  def locked_gem_version(gem_name)
+    d = Bundler::Definition.build(gem_file_path, lock_file_path, false)
+    d.locked_gems.dependencies[gem_name].requirement.requirements.first.last.version
+  end
+
+  def rake_version
+    locked_gem_version("rake")
+  end
+
+  def test_unit_version
+    locked_gem_version("test-unit")
+  end
+
+  def bundler_version
+    d = Bundler::Definition.build(gem_file_path, lock_file_path, false)
+    d.locked_gems.bundler_version.version
+  end
+
   def class_name
     "#{capitalized_name}#{type.capitalize}"
   end
diff --git a/templates/new_gem/fluent-plugin.gemspec.erb b/templates/new_gem/fluent-plugin.gemspec.erb
index c2cb616b42..6eb8a54bfc 100644
--- a/templates/new_gem/fluent-plugin.gemspec.erb
+++ b/templates/new_gem/fluent-plugin.gemspec.erb
@@ -20,8 +20,8 @@ Gem::Specification.new do |spec|
   spec.test_files    = test_files
   spec.require_paths = ["lib"]
 
-  spec.add_development_dependency "bundler", "~> 1.14"
-  spec.add_development_dependency "rake", "~> 12.0"
-  spec.add_development_dependency "test-unit", "~> 3.0"
+  spec.add_development_dependency "bundler", "~> <%= bundler_version %>"
+  spec.add_development_dependency "rake", "~> <%= rake_version %>"
+  spec.add_development_dependency "test-unit", "~> <%= test_unit_version %>"
   spec.add_runtime_dependency "fluentd", [">= 0.14.10", "< 2"]
 end