# Support for Guard gem

**URL:** <https://discourse.dry-rb.org/t/support-for-guard-gem/587>\
**Category:** dry-validation\
**Created:** [July 18, 2018, 8:34am UTC](https://discourse.dry-rb.org/t/support-for-guard-gem/587 "2018-07-18T08:34:52Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![esparta](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.dry-rb.org/esparta/32/244_2.png) [@esparta](https://discourse.dry-rb.org/u/esparta)\
**Post date:** [July 18, 2018, 8:34am UTC](https://discourse.dry-rb.org/t/support-for-guard-gem/587/1 "2018-07-18T08:34:52Z")

</div>

I know this sound a lot like an [xkcd://1172](https://xkcd.com/1172/): Every change breaks someone’s workflow, but I can try to don’t.

While I was trying to formulate a Proof of concept of a bug related to Dry-Validation I though it was a good idea to spin my local [Guard](https://github.com/guard/guard) and start iterating my case using an new spec file (and being sure I didn’t break some other spec also). When I tried to use Guard got this error:

```auto
Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/guard-rspec-4.7.3/lib/guard/rspec_defaults.rb:1:in `<top (required)>': Guard is not a module (TypeError)

```

Going deep on this, turns out Dry Validation defines a class called Guard, specifically `Dry::Validation::Guard` in `lib/dry/validation/schema_compiler.rb`, since is a class, Guard gem cannot work as intended because expect to be a module.

Is there any chance to rename the conflicting class to something like `Dry::Validation::InternalGuard`? The following diff made possible to continue working with Guard as expected:

```diff
diff --git a/lib/dry/validation/executor.rb b/lib/dry/validation/executor.rb │
index 330be83..11ab58e 100644 │
--- a/lib/dry/validation/executor.rb │
+++ b/lib/dry/validation/executor.rb │
@@ -45,7 +45,7 @@ module Dry │
       def call(input, result) │
         rules.each_with_object(result) do |(name, checks), hash| │
           checks.each do |check| │
- check_res = check.is_a?(Guard) ? check.(input, result) : check.(input) │
+ check_res = check.is_a?(InternalGuard) ? check.(input, result) : check.(input) │
             if hash.key?(name) │
               if hash[name].is_a?(Array) │
                 hash[name] << check_res

diff --git a/lib/dry/validation/schema_compiler.rb b/lib/dry/validation/schema_compiler.rb │
index 240345b..1878093 100644 │
--- a/lib/dry/validation/schema_compiler.rb │
+++ b/lib/dry/validation/schema_compiler.rb │
@@ -2,7 +2,7 @@ require 'dry/logic/rule_compiler' │
                                                                                                 │
 module Dry │
   module Validation │
- class Guard │
+ class InternalGuard │
       attr_reader :rule, :deps │
                                                                                                 │
       def initialize(rule, deps) │
@@ -70,7 +70,7 @@ module Dry │
                                                                                                 │
       def visit_guard(node) │
         deps, other = node │
- Guard.new(visit(other), deps) │
+ InternalGuard.new(visit(other), deps) │
       end │
                                                                                                 │
       def visit_type(type)

```

Of course I’d understand if this is not possible.

---

<div class="post-metadata">

**Author:** ![flash-gordon](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.dry-rb.org/flash-gordon/32/494_2.png) [@flash-gordon](https://discourse.dry-rb.org/u/flash-gordon)\
**Post date:** [July 19, 2018, 9:23am UTC](https://discourse.dry-rb.org/t/support-for-guard-gem/587/2 "2018-07-19T09:23:58Z")

</div>

The proper fix is to add `require 'dry/validation/schema_compiler'` at the top of `dry/validation/executor.rb`

---

<div class="post-metadata">

**Author:** ![esparta](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.dry-rb.org/esparta/32/244_2.png) [@esparta](https://discourse.dry-rb.org/u/esparta)\
**Post date:** [July 21, 2018, 7:31am UTC](https://discourse.dry-rb.org/t/support-for-guard-gem/587/3 "2018-07-21T07:31:20Z")

</div>

I tried that fix and still have the same problem.

For some reason while running any spec through Guad/RSpec, for ruby interpreter there’s a constant called `Guard` even if it’s namespaced as `Dry::Validation::Guard`, so later on, guard-rspec tries to redefine `Guard` as a module making ruby not happy as in running like this:

```ruby
class Guard
end
# => nil
module Guard
end
TypeError: Guard is not a module
        from (irb):3
        from /Users/esparta/.rvm/rubies/ruby-2.2.9/bin/irb:11:in `<main>'

```

While we mean to run like this:

```ruby
module Dry
  module Validation
    class Guard
    end
  end
end
# => nil
module Guard
end
# => nil
Dry::Validation::Guard.class
# => Class
Guard.class
# => Module

```

Looks like there’s a lot of unknown facts on my stack (Guard + Guard/RSpec) and is not worthy to continue digging since there’s no use case and I’m the only one using it 🙂

Thanks for your help and time.

Tracelog:

```auto
23:18:53 - INFO - Running: spec/integration/schema/nested_schemas_two_spec.rb
/Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/guard-rspec-4.7.3/lib/guard/rspec_defaults.rb:1:in `<top (required)>': Guard is not $
 module (TypeError)
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/guard-rspec-4.7.3/lib/guard/rspec_formatter_results_path.rb:1:in `requi$
e_relative'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/guard-rspec-4.7.3/lib/guard/rspec_formatter_results_path.rb:1:in `<top $
required)>'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/guard-rspec-4.7.3/lib/guard/rspec_formatter.rb:10:in `require_relative'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/guard-rspec-4.7.3/lib/guard/rspec_formatter.rb:10:in `<top (required)>'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/rspec-core-3.7.1/lib/rspec/core/configuration.rb:1455:in `require'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/rspec-core-3.7.1/lib/rspec/core/configuration.rb:1455:in `block in requ$
res='
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/rspec-core-3.7.1/lib/rspec/core/configuration.rb:1455:in `each'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/rspec-core-3.7.1/lib/rspec/core/configuration.rb:1455:in `requires='
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/rspec-core-3.7.1/lib/rspec/core/configuration_options.rb:112:in `block $
n process_options_into'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/rspec-core-3.7.1/lib/rspec/core/configuration_options.rb:111:in `each'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/rspec-core-3.7.1/lib/rspec/core/configuration_options.rb:111:in `proces$
_options_into'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/rspec-core-3.7.1/lib/rspec/core/configuration_options.rb:21:in `configu$
e'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/rspec-core-3.7.1/lib/rspec/core/runner.rb:99:in `setup'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/rspec-core-3.7.1/lib/rspec/core/runner.rb:86:in `run'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/rspec-core-3.7.1/lib/rspec/core/runner.rb:71:in `run'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/rspec-core-3.7.1/lib/rspec/core/runner.rb:45:in `invoke'

        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/gems/rspec-core-3.7.1/exe/rspec:4:in `<top (required)>'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/bin/rspec:23:in `load'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/bin/rspec:23:in `<main>'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/bin/ruby_executable_hooks:15:in `eval'
        from /Users/esparta/.rvm/gems/ruby-2.2.9@dry-rb/bin/ruby_executable_hooks:15:in `<main>'

```