RailsチュートリアルにてHerokuにプッシュできない問題

Question

環境

cloud9
ruby 2.6.3
rails 5.1.6

Herokuにプッシュするために以下のコマンドを実行するとエラーが発生してしまいます。

ec2-user:~/environment/toy_app (master) $ git push heroku master
Counting objects: 88, done.
Compressing objects: 100% (74/74), done.
Writing objects: 100% (88/88), 20.94 KiB | 1.23 MiB/s, done.
Total 88 (delta 5), reused 0 (delta 0)
remote: Compressing source files... done.
remote: Building source:
remote: 
remote:  !     Warning: Multiple default buildpacks reported the ability to handle this app. The first buildpack in the list below will be used.
remote:                         Detected buildpacks: Ruby,Node.js
remote:                         See https://devcenter.heroku.com/articles/buildpacks#buildpack-detect-order
remote: -----> Ruby app detected
remote: -----> Installing bundler 1.17.3
remote: -----> Removing BUNDLED WITH version in the Gemfile.lock

～一部省略～

0
remote:        Fetching actionview 5.1.7
remote:        Installing actionview 5.1.7
remote:        Fetching actionpack 5.1.7
remote:        Installing actionpack 5.1.7
remote:        Fetching actioncable 5.1.7
remote:        Fetching actionmailer 5.1.7
remote:        Fetching railties 5.1.7
remote:        Installing actioncable 5.1.7
remote:        Installing actionmailer 5.1.7
remote:        Installing railties 5.1.7
remote:        Fetching sprockets-rails 3.2.1
remote:        Installing sprockets-rails 3.2.1
remote:        Fetching coffee-rails 4.2.2
remote:        Fetching rails 5.1.7
remote:        Fetching sass-rails 5.0.7
remote:        Installing rails 5.1.7
remote:        Installing coffee-rails 4.2.2
remote:        Installing sass-rails 5.0.7
remote:        Gem::Ext::BuildError: ERROR: Failed to build gem native extension.
remote:        
remote:        current directory:
remote:        /tmp/build_37a5f20d089ab3c9564f8c001dadab45/vendor/bundle/ruby/2.6.0/gems/sqlite3-1.4.2/ext/sqlite3
remote:        /tmp/build_37a5f20d089ab3c9564f8c001dadab45/vendor/ruby-2.6.5/bin/ruby -I
remote:        /tmp/build_37a5f20d089ab3c9564f8c001dadab45/vendor/ruby-2.6.5/lib/ruby/2.6.0 -r
remote:        ./siteconf20200308-254-1suzju9.rb extconf.rb
remote:        checking for sqlite3.h... no
remote:        sqlite3.h is missing. Try 'brew install sqlite3',
remote:        'yum install sqlite-devel' or 'apt-get install libsqlite3-dev'
remote:        and check your shared library search path (the
remote:        location where your sqlite3 shared library is located).
remote:        *** extconf.rb failed ***
remote:        Could not create Makefile due to some reason, probably lack of necessary
remote:        libraries and/or headers.  Check the mkmf.log file for more details.  You may
remote:        need configuration options.
remote:        
remote:        Provided configuration options:
remote:         --with-opt-dir
remote:         --without-opt-dir
remote:         --with-opt-include
remote:         --without-opt-include=${opt-dir}/include
remote:         --with-opt-lib
remote:         --without-opt-lib=${opt-dir}/lib
remote:         --with-make-prog
remote:         --without-make-prog
remote:         --srcdir=.
remote:         --curdir
remote:        --ruby=/tmp/build_37a5f20d089ab3c9564f8c001dadab45/vendor/ruby-2.6.5/bin/$(RUBY_BASE_NAME)
remote:         --with-sqlcipher
remote:         --without-sqlcipher
remote:         --with-sqlite3-config
remote:         --without-sqlite3-config
remote:         --with-pkg-config
remote:         --without-pkg-config
remote:         --with-sqlcipher
remote:         --without-sqlcipher
remote:         --with-sqlite3-dir
remote:         --without-sqlite3-dir
remote:         --with-sqlite3-include
remote:         --without-sqlite3-include=${sqlite3-dir}/include
remote:         --with-sqlite3-lib
remote:         --without-sqlite3-lib=${sqlite3-dir}/lib
remote:        
remote:        To see why this extension failed to compile, please check the mkmf.log which can
remote:        be found here:
remote:        
remote:        /tmp/build_37a5f20d089ab3c9564f8c001dadab45/vendor/bundle/ruby/2.6.0/extensions/x86_64-linux/2.6.0/sqlite3-1.4.2/mkmf.log
remote:        
remote:        extconf failed, exit code 1
remote:        
remote:        Gem files will remain installed in
remote:        /tmp/build_37a5f20d089ab3c9564f8c001dadab45/vendor/bundle/ruby/2.6.0/gems/sqlite3-1.4.2
remote:        for inspection.
remote:        Results logged to
remote:        /tmp/build_37a5f20d089ab3c9564f8c001dadab45/vendor/bundle/ruby/2.6.0/extensions/x86_64-linux/2.6.0/sqlite3-1.4.2/gem_make.out
remote:        
remote:        An error occurred while installing sqlite3 (1.4.2), and Bundler cannot continue.
remote:        Make sure that `gem install sqlite3 -v '1.4.2' --source 'https://rubygems.org/'`
remote:        succeeds before bundling.
remote:        
remote:        In Gemfile:
remote:          sqlite3
remote: 
remote:  !
remote:  !     Failed to install gems via Bundler.
remote:  !     Detected sqlite3 gem which is not supported on Heroku:
remote:  !     https://devcenter.heroku.com/articles/sqlite3
remote:  !
remote:  !     Push rejected, failed to compile Ruby app.
remote: 
remote:  !     Push failed
remote: Verifying deploy...
remote: 
remote: !       Push rejected to polar-tundra-37862.
remote: 
To https://git.heroku.com/polar-tundra-37862.git
 ! [remote rejected] master -> master (pre-receive hook declined)
error: failed to push some refs to 'https://git.heroku.com/polar-tundra-37862.git'
ec2-user:~/environment/toy_app (master) $ 

以下エラー部分抜粋です。

remote:  !     Failed to install gems via Bundler.
remote:  !     Detected sqlite3 gem which is not supported on Heroku:
remote:  !     https://devcenter.heroku.com/articles/sqlite3

試したこと

エラー部分メッセージを読む限り、SQLiteが対応してない、ということかと思いましたがRailsチュートリアルの指示通りPostgreSQLと通信ができるようにgemファイルは以下のように編集済みです。

source 'https://rubygems.org'

gem 'rails',        '5.1.6'
gem 'puma',         '3.9.1'
gem 'sass-rails',   '5.0.6'
gem 'uglifier',     '3.2.0'
gem 'coffee-rails', '4.2.2'
gem 'jquery-rails', '4.3.1'
gem 'turbolinks',   '5.0.1'
gem 'jbuilder',     '2.7.0'

group :development, :test do
  gem 'sqlite3', '1.3.13'
  gem 'byebug',  '9.0.6', platform: :mri
end

group :development do
  gem 'web-console',           '3.5.1'
  gem 'listen',                '3.1.5'
  gem 'spring',                '2.0.2'
  gem 'spring-watcher-listen', '2.0.1'
end

group :production do
  gem 'pg', '0.20.0'
end

# Windows環境ではtzinfo-dataというgemを含める必要があります
gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]

そして以下のコマンドも実行済みです

$ bundle install --without production
$ git commit -a -m "Update Gemfile for Heroku"
```

解決方法のご教授願います。

Answer 1

おそらくですが

$ git commit -a -m "Update Gemfile for Heroku"

を先に実行して

$ bundle install --without production

を後に実行していたのが原因でした。