Add acceptance test suite

This change adds an acceptance test suite. These tests don't have great
failure messages currently and could likely stand to be broken into
smaller pieces.

Changes:
- Split up `spec` task to run all unittests before the acceptance tests.

Rakefile

@@ -6,6 +6,18 @@ namespace :dummy do
   Dummy::Application.load_tasks
 end
 
-RSpec::Core::RakeTask.new(:spec)
+task(:spec).clear
+desc "Run specs other than spec/acceptance"
+RSpec::Core::RakeTask.new("spec") do |task|
+  task.exclude_pattern = "spec/acceptance/**/*_spec.rb"
+  task.verbose = false
+end
+
+desc "Run acceptance specs in spec/acceptance"
+RSpec::Core::RakeTask.new("spec:acceptance") do |task|
+  task.pattern = "spec/acceptance/**/*_spec.rb"
+  task.verbose = false
+end
 
-task default: :spec
+desc "Run the specs and acceptance tests"
+task default: %w(spec spec:acceptance)

spec/acceptance/user_manages_functions_spec.rb

@@ -0,0 +1,47 @@
+require "acceptance_helper"
+
+describe "User manages functions" do
+  it "handles simple functions" do
+    successfully "rails generate fx:function test"
+    write_definition "test_v01", <<~EOS
+      CREATE OR REPLACE FUNCTION test() RETURNS text AS $$
+      BEGIN
+          RETURN 'test';
+      END;
+      $$ LANGUAGE plpgsql;
+    EOS
+    successfully "rake db:migrate"
+
+    result = execute("SELECT * FROM test() AS result")
+    expect(result).to eq("result" => "test")
+
+    successfully "rails generate fx:function test"
+    write_definition "test_v02", <<~EOS
+      CREATE OR REPLACE FUNCTION test() RETURNS text AS $$
+      BEGIN
+          RETURN 'testest';
+      END;
+      $$ LANGUAGE plpgsql;
+    EOS
+    successfully "rake db:migrate"
+
+    result = execute("SELECT * FROM test() AS result")
+    expect(result).to eq("result" => "testest")
+  end
+
+  def successfully(command)
+    `RAILS_ENV=test #{command}`
+    expect($?.exitstatus).to eq(0), "'#{command}' was unsuccessful"
+  end
+
+  def write_definition(file, contents)
+    File.open("db/functions/#{file}.sql", File::WRONLY) do |definition|
+      definition.truncate(0)
+      definition.write(contents)
+    end
+  end
+
+  def execute(command)
+    ActiveRecord::Base.connection.execute(command).first
+  end
+end

spec/acceptance_helper.rb

@@ -0,0 +1,33 @@
+require "bundler"
+
+ENV["RAILS_ENV"] = "test"
+
+RSpec.configure do |config|
+  config.around(:each) do |example|
+    Dir.chdir("spec/dummy") do
+      example.run
+    end
+  end
+
+  config.before(:suite) do
+    Dir.chdir("spec/dummy") do
+      system <<-CMD
+        git init 1>/dev/null &&
+        git add -A &&
+        git commit --no-gpg-sign --message 'initial' 1>/dev/null
+      CMD
+    end
+  end
+
+  config.after(:suite) do
+    Dir.chdir("spec/dummy") do
+      ActiveRecord::Base.connection.disconnect!
+      system <<-CMD
+        rake db:drop db:create &&
+        git add -A &&
+        git reset --hard HEAD 1>/dev/null &&
+        rm -rf .git/ 1>/dev/null
+      CMD
+    end
+  end
+end