Add RSpec

Gemfile.lock

@@ -1,23 +1,38 @@
 PATH
   remote: .
   specs:
-    singed (0.0.1)
-      colorize (~> 0.8.1)
+    singed (0.1.1)
+      colorize
       stackprof
 
 GEM
   remote: https://rubygems.org/
   specs:
     colorize (0.8.1)
+    diff-lcs (1.5.0)
     rake (13.0.6)
+    rspec (3.12.0)
+      rspec-core (~> 3.12.0)
+      rspec-expectations (~> 3.12.0)
+      rspec-mocks (~> 3.12.0)
+    rspec-core (3.12.1)
+      rspec-support (~> 3.12.0)
+    rspec-expectations (3.12.2)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.12.0)
+    rspec-mocks (3.12.4)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.12.0)
+    rspec-support (3.12.0)
     stackprof (0.2.17)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
   rake (~> 13.0)
+  rspec
   singed!
 
 BUNDLED WITH
-   2.2.30
+   2.4.4

README.md

@@ -32,7 +32,7 @@ Singed.output_directory = "tmp/slowness-exploration"
 If you are calling it in a loop, or with different variations, you can include a label on the filename:
 
 ```ruby
-flamegraph(label: "rspec") {
+flamegraph("rspec") {
   # your code here
 }
 ```

bin/rspec

@@ -0,0 +1,27 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'rspec' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../Gemfile", __dir__)
+
+bundle_binstub = File.expand_path("bundle", __dir__)
+
+if File.file?(bundle_binstub)
+  if File.read(bundle_binstub, 300).include?("This file was generated by Bundler")
+    load(bundle_binstub)
+  else
+    abort("Your `bin/bundle` was not generated by Bundler, so this binstub cannot run.
+Replace `bin/bundle` by running `bundle binstubs bundler --force`, then run this command again.")
+  end
+end
+
+require "rubygems"
+require "bundler/setup"
+
+load Gem.bin_path("rspec-core", "rspec")

lib/singed/kernel_ext.rb

@@ -1,15 +1,15 @@
 module Kernel
-  def flamegraph(label = nil, open: true, ignore_gc: false, interval: 1000, &block)
+  def flamegraph(label = nil, open: true, ignore_gc: false, interval: 1000, io: $stdout, &block)
     fg = Singed::Flamegraph.new(label: label, ignore_gc: ignore_gc, interval: interval)
     result = fg.record(&block)
     fg.save
 
     if open
       # use npx, so we don't have to add it as a dependency
-      puts "🔥📈 #{'Captured flamegraph, opening with'.colorize(:bold).colorize(:red)}: #{fg.open_command}"
+      io.puts "🔥📈 #{'Captured flamegraph, opening with'.colorize(:bold).colorize(:red)}: #{fg.open_command}"
       fg.open
     else
-      puts "🔥📈 #{'Captured flamegraph to file'.colorize(:bold).colorize(:red)}: #{fg.filename}"
+      io.puts "🔥📈 #{'Captured flamegraph to file'.colorize(:bold).colorize(:red)}: #{fg.filename}"
     end
 
     result

singed.gemspec

@@ -22,6 +22,7 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'stackprof'
 
   spec.add_development_dependency 'rake', '~> 13.0'
+  spec.add_development_dependency 'rspec'
 
   # For more information and examples about making a new gem, checkout our
   # guide at: https://bundler.io/guides/creating_gem.html

spec/singed/kernel_ext_spec.rb

@@ -0,0 +1,60 @@
+describe Kernel, "extension" do
+  let(:flamegraph) { 
+    instance_double(Singed::Flamegraph)
+  }
+
+  before do
+    allow(Singed::Flamegraph).to receive(:new).and_return(flamegraph)
+    allow(flamegraph).to receive(:record)
+    allow(flamegraph).to receive(:save)
+    allow(flamegraph).to receive(:open)
+    allow(flamegraph).to receive(:open_command)
+    allow(flamegraph).to receive(:filename)
+  end
+
+  let(:io) { StringIO.new }
+
+  it "works without any arguments" do
+    # * except what's needed to test
+    # note: use Object.new to get the actual flamegraph kernel extension, instead of the rspec-specific flamegraph
+    Object.new.flamegraph io: io do
+    end
+
+    expect(Singed::Flamegraph).to have_received(:new).with(label: nil, ignore_gc: false, interval: 1000)
+  end
+
+  it "works with explicit arguments" do
+    # note: use Object.new to get the actual flamegraph kernel extension, instead of the rspec-specific flamegraph
+    Object.new.flamegraph 'yellowjackets', ignore_gc: true, interval: 2000, io: io do
+    end
+
+    expect(Singed::Flamegraph).to have_received(:new).with(label: 'yellowjackets', ignore_gc: true, interval: 2000)
+  end
+
+  context "default" do
+    it "opens" do
+      Object.new.flamegraph open: true, io: io do
+      end
+
+      expect(flamegraph).to have_received(:open)
+    end
+  end
+
+  context "open: true" do
+    it "opens" do
+      Object.new.flamegraph open: true, io: io do
+      end
+
+      expect(flamegraph).to have_received(:open)
+    end
+  end
+
+  context "open: false" do
+    it "doesn't open" do
+      Object.new.flamegraph open: false, io: io do
+      end
+
+      expect(flamegraph).to_not have_received(:open)
+    end
+  end
+end

spec/spec_helper.rb

@@ -0,0 +1,101 @@
+# This file was generated by the `rspec --init` command. Conventionally, all
+# specs live under a `spec` directory, which RSpec adds to the `$LOAD_PATH`.
+# The generated `.rspec` file contains `--require spec_helper` which will cause
+# this file to always be loaded, without a need to explicitly require it in any
+# files.
+#
+# Given that it is always loaded, you are encouraged to keep this file as
+# light-weight as possible. Requiring heavyweight dependencies from this file
+# will add to the boot time of your test suite on EVERY test run, even for an
+# individual file that may not need all of that loaded. Instead, consider making
+# a separate helper file that requires the additional dependencies and performs
+# the additional setup, and require it from the spec files that actually need
+# it.
+#
+# See https://rubydoc.info/gems/rspec-core/RSpec/Core/Configuration
+
+require 'singed'
+
+RSpec.configure do |config|
+  # rspec-expectations config goes here. You can use an alternate
+  # assertion/expectation library such as wrong or the stdlib/minitest
+  # assertions if you prefer.
+  config.expect_with :rspec do |expectations|
+    # This option will default to `true` in RSpec 4. It makes the `description`
+    # and `failure_message` of custom matchers include text for helper methods
+    # defined using `chain`, e.g.:
+    #     be_bigger_than(2).and_smaller_than(4).description
+    #     # => "be bigger than 2 and smaller than 4"
+    # ...rather than:
+    #     # => "be bigger than 2"
+    expectations.include_chain_clauses_in_custom_matcher_descriptions = true
+  end
+
+  # rspec-mocks config goes here. You can use an alternate test double
+  # library (such as bogus or mocha) by changing the `mock_with` option here.
+  config.mock_with :rspec do |mocks|
+    # Prevents you from mocking or stubbing a method that does not exist on
+    # a real object. This is generally recommended, and will default to
+    # `true` in RSpec 4.
+    mocks.verify_partial_doubles = true
+  end
+
+  # This option will default to `:apply_to_host_groups` in RSpec 4 (and will
+  # have no way to turn it off -- the option exists only for backwards
+  # compatibility in RSpec 3). It causes shared context metadata to be
+  # inherited by the metadata hash of host groups and examples, rather than
+  # triggering implicit auto-inclusion in groups with matching metadata.
+  config.shared_context_metadata_behavior = :apply_to_host_groups
+
+# The settings below are suggested to provide a good initial experience
+# with RSpec, but feel free to customize to your heart's content.
+=begin
+  # This allows you to limit a spec run to individual examples or groups
+  # you care about by tagging them with `:focus` metadata. When nothing
+  # is tagged with `:focus`, all examples get run. RSpec also provides
+  # aliases for `it`, `describe`, and `context` that include `:focus`
+  # metadata: `fit`, `fdescribe` and `fcontext`, respectively.
+  config.filter_run_when_matching :focus
+
+  # Allows RSpec to persist some state between runs in order to support
+  # the `--only-failures` and `--next-failure` CLI options. We recommend
+  # you configure your source control system to ignore this file.
+  config.example_status_persistence_file_path = "spec/examples.txt"
+
+  # Limits the available syntax to the non-monkey patched syntax that is
+  # recommended. For more details, see:
+  # https://relishapp.com/rspec/rspec-core/docs/configuration/zero-monkey-patching-mode
+  config.disable_monkey_patching!
+
+  # This setting enables warnings. It's recommended, but in some cases may
+  # be too noisy due to issues in dependencies.
+  config.warnings = true
+
+  # Many RSpec users commonly either run the entire suite or an individual
+  # file, and it's useful to allow more verbose output when running an
+  # individual spec file.
+  if config.files_to_run.one?
+    # Use the documentation formatter for detailed output,
+    # unless a formatter has already been configured
+    # (e.g. via a command-line flag).
+    config.default_formatter = "doc"
+  end
+
+  # Print the 10 slowest examples and example groups at the
+  # end of the spec run, to help surface which specs are running
+  # particularly slow.
+  config.profile_examples = 10
+
+  # Run specs in random order to surface order dependencies. If you find an
+  # order dependency and want to debug it, you can fix the order by providing
+  # the seed, which is printed after each run.
+  #     --seed 1234
+  config.order = :random
+
+  # Seed global randomization in this process using the `--seed` CLI option.
+  # Setting this allows you to use `--seed` to deterministically reproduce
+  # test failures related to randomization by passing the same `--seed` value
+  # as the one that triggered the failure.
+  Kernel.srand config.seed
+=end
+end