From 3f1527b3e38208fb76c0df3795dd80c74f192762 Mon Sep 17 00:00:00 2001
From: schneems <richard.schneeman+foo@gmail.com>
Date: Wed, 3 Nov 2021 12:57:09 -0500
Subject: [PATCH] Add profiler generation to test suite

You can output profiler data to the `tmp` directory by running:

```
$ DEBUG_PERF=1 bundle exec rspec spec/integration/dead_end_spec.rb
```

Some outputs are in text format, some are html. See https://ruby-prof.github.io/#reports for more info. One interesting one, is the "kcachegrind" interface. To view this on mac:

```
$ brew install qcachegrind
```

Open:

```
$ qcachegrind tmp/<dir>/profile.callgrind.out.14508
```
---
 Gemfile                           |  1 +
 Gemfile.lock                      |  4 +++-
 README.md                         | 22 +++++++++++++++++++-
 lib/dead_end.rb                   | 10 +++++++++
 lib/dead_end/code_search.rb       |  3 +--
 spec/integration/dead_end_spec.rb | 34 +++++++++++++++++++++++--------
 6 files changed, 62 insertions(+), 12 deletions(-)

diff --git a/Gemfile b/Gemfile
index b0065fe..de47413 100644
--- a/Gemfile
+++ b/Gemfile
@@ -9,3 +9,4 @@ gem "rake", "~> 12.0"
 gem "rspec", "~> 3.0"
 gem "stackprof"
 gem "standard"
+gem "ruby-prof"
diff --git a/Gemfile.lock b/Gemfile.lock
index eb0c618..4e5230c 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -42,6 +42,7 @@ GEM
     rubocop-performance (1.11.5)
       rubocop (>= 1.7.0, < 2.0)
       rubocop-ast (>= 0.4.0)
+    ruby-prof (1.4.3)
     ruby-progressbar (1.11.0)
     stackprof (0.2.16)
     standard (1.3.0)
@@ -56,8 +57,9 @@ DEPENDENCIES
   dead_end!
   rake (~> 12.0)
   rspec (~> 3.0)
+  ruby-prof
   stackprof
   standard
 
 BUNDLED WITH
-   2.2.29
+   2.2.30
diff --git a/README.md b/README.md
index d1f670e..6932e7f 100644
--- a/README.md
+++ b/README.md
@@ -170,7 +170,27 @@ To install this gem onto your local machine, run `bundle exec rake install`. To
 You can see changes to output against a variety of invalid code by running specs and using the `DEBUG_DISPLAY=1` environment variable. For example:
 
 ```
-$ DEBUG_DISPLAY=1 be rspec spec/ --format=failures
+$ DEBUG_DISPLAY=1 bundle exec rspec spec/ --format=failures
+```
+
+### Run profiler
+
+You can output profiler data to the `tmp` directory by running:
+
+```
+$ DEBUG_PERF=1 bundle exec rspec spec/integration/dead_end_spec.rb
+```
+
+Some outputs are in text format, some are html, the raw marshaled data is available in `raw.rb.marshal`. See https://ruby-prof.github.io/#reports for more info. One interesting one, is the "kcachegrind" interface. To view this on mac:
+
+```
+$ brew install qcachegrind
+```
+
+Open:
+
+```
+$ qcachegrind tmp/last/profile.callgrind.out.<numbers>
 ```
 
 ## Contributing
diff --git a/lib/dead_end.rb b/lib/dead_end.rb
index 900f6e5..f93a276 100644
--- a/lib/dead_end.rb
+++ b/lib/dead_end.rb
@@ -28,6 +28,16 @@ def self.handle_error(e)
     raise e
   end
 
+  def self.record_dir(dir)
+    time = Time.now.strftime("%Y-%m-%d-%H-%M-%s-%N")
+    dir = Pathname(dir)
+    symlink = dir.join("last").tap { |path| path.delete if path.exist? }
+    dir.join(time).tap { |path|
+      path.mkpath
+      FileUtils.symlink(path.basename, symlink)
+    }
+  end
+
   def self.call(source:, filename: DEFAULT_VALUE, terminal: DEFAULT_VALUE, record_dir: nil, timeout: TIMEOUT_DEFAULT, io: $stderr)
     search = nil
     filename = nil if filename == DEFAULT_VALUE
diff --git a/lib/dead_end/code_search.rb b/lib/dead_end/code_search.rb
index 400cf32..c90a33b 100644
--- a/lib/dead_end/code_search.rb
+++ b/lib/dead_end/code_search.rb
@@ -43,8 +43,7 @@ class CodeSearch
 
     def initialize(source, record_dir: ENV["DEAD_END_RECORD_DIR"] || ENV["DEBUG"] ? "tmp" : nil)
       if record_dir
-        @time = Time.now.strftime("%Y-%m-%d-%H-%M-%s-%N")
-        @record_dir = Pathname(record_dir).join(@time).tap { |p| p.mkpath }
+        @record_dir = DeadEnd.record_dir(record_dir)
         @write_count = 0
       end
 
diff --git a/spec/integration/dead_end_spec.rb b/spec/integration/dead_end_spec.rb
index e21e9a8..dc093bb 100644
--- a/spec/integration/dead_end_spec.rb
+++ b/spec/integration/dead_end_spec.rb
@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require_relative "../spec_helper"
+require "ruby-prof"
 
 module DeadEnd
   RSpec.describe "Integration tests that don't spawn a process (like using the cli)" do
@@ -80,17 +81,34 @@ module DeadEnd
           source: file.read,
           filename: file
         )
-
-        expect(io.string).to_not include("def ruby_install_binstub_path")
-        expect(io.string).to include(<<~'EOM')
-          ❯ 1067    def add_yarn_binary
-          ❯ 1068      return [] if yarn_preinstalled?
-          ❯ 1069  |
-          ❯ 1075    end
-        EOM
       end
       debug_display(io.string)
       debug_display(benchmark)
+
+      expect(io.string).to_not include("def ruby_install_binstub_path")
+      expect(io.string).to include(<<~'EOM')
+        ❯ 1067    def add_yarn_binary
+        ❯ 1068      return [] if yarn_preinstalled?
+        ❯ 1069  |
+        ❯ 1075    end
+      EOM
+
+      if ENV["DEBUG_PERF"]
+        result = RubyProf.profile do
+          DeadEnd.call(
+            io: io,
+            source: file.read,
+            filename: file
+          )
+        end
+
+        dir = DeadEnd.record_dir("tmp")
+
+        printer = RubyProf::MultiPrinter.new(result, [:flat, :graph, :graph_html, :tree, :call_tree, :stack, :dot])
+        printer.print(path: dir, profile: "profile")
+
+        dir.join("raw.rb.marshal").write(Marshal.dump(result))
+      end
     end
 
     it "handles heredocs" do