ためすう

$ ruby --version
ruby 2.6.3p62 (2019-04-16 revision 67580) [x86_64-darwin17]

$ rails --version
Rails 5.2.4.1

class Book < ApplicationRecord
  belongs_to :auther, class_name: Author
end

Rails.application.configure do
  # 抜粋
  # Do not eager load code on boot.
  config.eager_load = false
end

$ bundle exec rails c
Running via Spring preloader in process 5654
Loading development environment (Rails 5.2.4.1)
irb(main):001:0> Rails.application.eager_load!
Traceback (most recent call last):
        3: from (irb):1
        2: from app/models/book.rb:1:in `<main>'
        1: from app/models/book.rb:3:in `<class:Book>'
NameError (uninitialized constant Book::Author)

$ bundle exec rails runner 'Rails.application.eager_load!'
Running via Spring preloader in process 7687
Please specify a valid ruby command or the path of a script to run.
Run 'bin/rails runner -h' for help.

uninitialized constant Book::Author

$ hugo version
Hugo Static Site Generator v0.53/extended darwin/amd64 BuildDate: unknown

$ brew install hugo

$ hugo new site tech-blog

$ git submodule add https://github.com/qqhann/hugo-primer themes/hugo-primer

$ echo 'theme = "hugo-primer"' >> config.toml

$ hugo new post/my-first-post.md

$ hugo server -D

$ ruby --version
ruby 2.6.3p62 (2019-04-16 revision 67580) [x86_64-darwin17]

$ rails --version
Rails 6.0.3.2

$ rails runner 'puts Rails.env'

Running via Spring preloader in process 37027
development

class Sample
  def self.hello
    puts 'called: hello'
    puts Rails.env
  end
end

Sample.hello

$ rails runner lib/hoge.rb
Running via Spring preloader in process 38718
called: hello
development

<?php

echo 'hoge'

class Sample
  def hoge
    p 'hoge'
  end
end

Sample.new.hoge

$ file a.php
a.php: PHP script text, ASCII text

$ file b.rb
b.rb: Ruby module source text, ASCII text

$ ruby --version
ruby 2.6.3p62 (2019-04-16 revision 67580) [x86_64-darwin17]

$ rails --version
Rails 5.2.3

$ gem list | grep rspec-rails
rspec-rails (3.8.2)

require 'rails_helper'

RSpec.describe Task, type: :model do
  it 'failedケース pendingあり' do
    pending('pending理由を何か書く')

    raise '例外発生1'
  end

  it 'successケース pendingなし' do
    expect(3 + 4).to eq 7
  end

  it 'successケース pendingあり' do
    pending('pending理由を何か書く')
  end
end

$ bundle exec rspec spec/models/task11_spec.rb

Task
  failedケース pendingあり (PENDING: pending理由を何か書く)
  successケース pendingなし
  successケース pendingあり (FAILED - 1)

Pending: (Failures listed here are expected and do not affect your suite's status)

  1) Task failedケース pendingあり
     # pending理由を何か書く
     Failure/Error: raise '例外発生1'

     RuntimeError:
       例外発生1
     # ./spec/models/task11_spec.rb:7:in `block (2 levels) in <top (required)>'

Failures:

  1) Task successケース pendingあり FIXED
     Expected pending 'pending理由を何か書く' to fail. No error was raised.
     # ./spec/models/task11_spec.rb:14

Finished in 0.00317 seconds (files took 1.58 seconds to load)
3 examples, 1 failure, 1 pending

Failed examples:

rspec ./spec/models/task11_spec.rb:14 # Task successケース pendingあり

$ foreman start

$ postgres -D /usr/local/var/postgres

$ bin/rake 'component:convert[select2,4.0.3]'

$ gem unpack public/gems/rails-assets-select2-4.0.3.gem

$ diff -r {1. rails-assets から gem を生成したもの} {2. rails-assets を Gemfile に書いてインストールされたもの}

$ g++ --version
g++ (Homebrew GCC 9.2.0) 9.2.0
Copyright (C) 2019 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

#include <bits/stdc++.h>
#include <cassert>
using namespace std;

int main() {
    vector<int> v;
    // 5個の要素を値10で埋める
    v.assign(5, 10);

    for (auto val : v) {
        cout << val << " ";
    }
    cout << endl;

    cout << "---" << endl;
    // 2個の要素に置き換える
    vector<int> before_v = {5, 4, 3, 2, 1};
    v.assign(before_v.begin(), before_v.begin() + 2);
    for (auto val : v) {
        cout << val << " ";
    }
    cout << endl;
}

10 10 10 10 10
---
5 4

$ ruby --version
ruby 2.5.5p157 (2019-03-15 revision 67260) [x86_64-darwin17]

appraise "rails-5.1.0" do
  gem "rails", "5.1.0"
end
​
appraise "rails-5.2.3" do
  gem "rails", "5.2.3"
end
​
appraise "rails-6.0.0" do
  gem "rails", "6.0.0"
end

group :development do
  # 省略...
  gem 'appraisal'
end

$ bundle install

$ bundle exec appraisal install

gemfiles/rails_5.1.0.gemfile
gemfiles/rails_5.2.3.gemfile
gemfiles/rails_6.0.0.gemfile

require 'rails_helper'
​
RSpec.describe User, type: :model do
  it '計算1 should' do
    (1 + 2).should eq 3
  end
​
  it '計算2 expect' do
    expect(3 + 4).to eq 7
  end
end

$ RAILS_ENV=test bundle exec appraisal rspec spec/models/user_spec.rb

>> BUNDLE_GEMFILE=/my-gem/gemfiles/rails_5.1.0.gemfile bundle exec rspec spec/models/user_spec.rb
Run options: include {:focus=>true}
​
All examples were filtered out; ignoring {:focus=>true}
..
​
1 deprecation warning total
​
Finished in 0.21237 seconds (files took 5.08 seconds to load)
2 examples, 0 failures

>> BUNDLE_GEMFILE=/my-gem/gemfiles/rails_5.2.3.gemfile bundle exec rspec spec/models/user_spec.rb
Run options: include {:focus=>true}
​
All examples were filtered out; ignoring {:focus=>true}
..
​
1 deprecation warning total
​
Finished in 0.22129 seconds (files took 5.45 seconds to load)
2 examples, 0 failures

>> BUNDLE_GEMFILE=/my-gem/gemfiles/rails_6.0.0.gemfile bundle exec rspec spec/models/user_spec.rb
Run options: include {:focus=>true}

All examples were filtered out; ignoring {:focus=>true}
..

1 deprecation warning total

Finished in 0.07676 seconds (files took 6.03 seconds to load)
2 examples, 0 failures

$ RAILS_ENV=test bundle exec appraisal rails-5.2.3 rspec spec/models/user_spec.rb

$ g++ --version
g++ (Homebrew GCC 9.2.0) 9.2.0
Copyright (C) 2019 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

#include <bits/stdc++.h>
using namespace std;

int main() {
    // degree -> radian
    double target_degree = 45;
    double radian = target_degree * M_PI / 180.0;
    printf("radian: %.10f\n", radian);

    // radian -> degree
    double degree = radian * 180.0 / M_PI;
    printf("degree: %.10f\n", degree);
}

radian: 0.7853981634
degree: 45.0000000000

$ g++ --version
g++ (Homebrew GCC 9.2.0) 9.2.0
Copyright (C) 2019 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

#include <bits/stdc++.h>
using namespace std;

int main() {
    vector<int> v = {5, 3, 2, 9, 8};

    auto iter = v.begin();
    cout << "begin(): " << *iter << endl;
    iter = next(iter);
    cout << "begin() + next1回: " << *iter << endl;
    iter = next(iter);
    cout << "begin() + next2回: " << *iter << endl;

    iter = prev(iter);
    cout << "begin() + next2回 + prev1回: " << *iter << endl;

    // この指定だと2回進む
    iter++;
    iter += 1;
    cout << "begin() + next2回 + prev1回 + 2回進む " << *iter << endl;
}

begin(): 5
begin() + next1回: 3
begin() + next2回: 2
begin() + next2回 + prev1回: 3
begin() + next2回 + prev1回 + 2回進む 9