add rbx-3.86, add Pry::Platform.known_engines, allow expected failures in spec suite (#1694)

* Add Pry::Platform.known_engines

* Add fixes for rbx-3.86, and cleanup .travis.yml

* Optionally skip a test on specific Ruby engine(s).
   And tag specs that currently do not pass on Rubinius.

Travis takes much longer to complete after this change.
Maybe there are switches we can pass to speed up Rubinius,
or this will improve on new versions of Rubinius.

8 files changed, 45 insertions, 16 deletions

diff --git a/.travis.yml b/.travis.yml
index 7ea15d7f..5aa48822 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,10 +5,9 @@ rvm:
   - 2.2
   - 2.3
   - 2.4
-  - ruby-head
-  - rbx-3.69
+  - rbx-3.86
   - jruby-9.1.14.0
-  - jruby
+  - ruby-head
   - jruby-head
 
 install:
@@ -23,9 +22,7 @@ sudo: false
 matrix:
   allow_failures:
     - rvm: ruby-head
-    - rvm: jruby
     - rvm: jruby-head
-    - rvm: rbx-3.69
     - rvm: 2.4 # https://bugs.ruby-lang.org/issues/13537
 
 notifications:
diff --git a/CHANGELOG.md b/CHANGELOG.md
index f40aef93..8792edfb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,11 @@
 
 #### Features
 
+* Add Pry::Platform#known_engines, returns an Array of Ruby engines
+  (MRI, JRuby, Rubinius) that Pry is known to run on.
+
+See pull request [#1694](https://github.com/pry/pry/pull/1694).
+
 * Deprecate Pry::Command#text. Please use black(), white(), etc directly
   instead (as you would with helper functions from BaseHelpers and
   CommandHelpers)
@@ -50,6 +55,14 @@ See pull request [#1691](https://github.com/pry/pry/pull/1691).
 
 See pull request [#1674](https://github.com/pry/pry/pull/1674).
 
+
+#### Pry developers
+
+* Optionally skip a spec on specific Ruby engine(s) by providing `expect_failure: [:mri, :jruby]`
+  as a metadata Hash to the example group.
+
+See pull request [#1694](https://github.com/pry/pry/pull/1694).
+
 ### 0.11.0
 
 * Add alias 'whereami[?!]+' for 'whereami' command. ([#1597](https://github.com/pry/pry/pull/1597))
diff --git a/lib/pry/platform.rb b/lib/pry/platform.rb
index 5593d1a0..ea273888 100644
--- a/lib/pry/platform.rb
+++ b/lib/pry/platform.rb
@@ -90,4 +90,12 @@ module Pry::Platform
   def mri_2?
     !!(mri? and RUBY_VERSION =~ /\A2/)
   end
+
+  #
+  #  @return [Array<Symbol>]
+  #    Returns an Array of Ruby engines that Pry is known to run on.
+  #
+  def known_engines
+    [:jruby, :rbx, :mri]
+  end
 end
diff --git a/spec/commands/save_file_spec.rb b/spec/commands/save_file_spec.rb
index 8141e6c6..963380ab 100644
--- a/spec/commands/save_file_spec.rb
+++ b/spec/commands/save_file_spec.rb
@@ -20,7 +20,7 @@ describe "save-file" do
 
         @t.eval("save-file '#{path}' --to '#{@path}'")
 
-       
+
         expect(File.read(@path)).to eq(File.read(path))
       end
     end
@@ -141,7 +141,7 @@ describe "save-file" do
   end
 
   describe "saving commands" do
-    it 'should save a command to a file' do
+    it 'should save a command to a file', expect_failure: [:rbx] do
       @t.eval "save-file --to '#{@path}' show-source"
       cmd_source = Pry.config.commands["show-source"].source
       expect(File.read(@path)).to eq(cmd_source)
diff --git a/spec/commands/show_source_spec.rb b/spec/commands/show_source_spec.rb
index f0f19ec9..495caabf 100644
--- a/spec/commands/show_source_spec.rb
+++ b/spec/commands/show_source_spec.rb
@@ -623,13 +623,13 @@ describe "show-source" do
             end
 
             describe "when current context is a C object" do
-              it "should display a warning, and not monkey-patched definition" do
+              it "should display a warning, and not monkey-patched definition", expect_failure: [:rbx] do
                 out = pry_eval([1, 2, 3], 'show-source')
                 expect(out).not_to match(/doge/)
                 expect(out).to match(/warning/i)
               end
 
-              it "recommends to use the --all switch when other candidates are found" do
+              it "recommends to use the --all switch when other candidates are found", expect_failure: [:rbx] do
                 out = pry_eval([], 'show-source')
                 expect(out).to match(/'--all' switch/i)
               end
diff --git a/spec/helper.rb b/spec/helper.rb
index 97f5dfd1..1899da3d 100644
--- a/spec/helper.rb
+++ b/spec/helper.rb
@@ -42,6 +42,17 @@ RSpec.configure do |config|
   config.include Pry::Testable::Utility
   include Pry::Testable::Evalable
   include Pry::Testable::Variables
+
+  # Optionally skip a test on specific Ruby engine(s).
+  # Please use this feature sparingly! It is better that a feature works than not.
+  # Inapplicable features are OK.
+  config.before(:each) do |example|
+    Pry::Platform.known_engines.each do |engine|
+      example.metadata[:expect_failure].to_a.include?(engine) and
+      Pry::Platform.public_send(:"#{engine}?")                and
+      skip("This spec is failing or inapplicable on #{engine}.")
+    end
+  end
 end
 
 puts "Ruby v#{RUBY_VERSION} (#{defined?(RUBY_ENGINE) ? RUBY_ENGINE : "ruby"}), Pry v#{Pry::VERSION}, method_source v#{MethodSource::VERSION}, CodeRay v#{CodeRay::VERSION}, Pry::Slop v#{Pry::Slop::VERSION}"
diff --git a/spec/hooks_spec.rb b/spec/hooks_spec.rb
index 686b4736..be37f17e 100644
--- a/spec/hooks_spec.rb
+++ b/spec/hooks_spec.rb
@@ -175,13 +175,13 @@ describe Pry::Hooks do
   describe "getting hooks" do
     describe "get_hook" do
       it 'should return the correct requested hook' do
-        run = false
-        fun = false
-        @hooks.add_hook(:test_hook, :my_name) { run = true }
-        @hooks.add_hook(:test_hook, :my_name2) { fun = true }
+        run1 = false
+        run2 = false
+        @hooks.add_hook(:test_hook, :my_name) { run1 = true }
+        @hooks.add_hook(:test_hook, :my_name2) { run2 = true }
         @hooks.get_hook(:test_hook, :my_name).call
-        expect(run).to eq true
-        expect(fun).to eq false
+        expect(run1).to eq true
+        expect(run2).to eq false
       end
 
       it 'should return nil if hook does not exist' do
diff --git a/spec/pryrc_spec.rb b/spec/pryrc_spec.rb
index 9324b5de..fcf2d5d7 100644
--- a/spec/pryrc_spec.rb
+++ b/spec/pryrc_spec.rb
@@ -37,7 +37,7 @@ describe Pry do
       end
     end
 
-    it "should not load the pryrc if pryrc's directory permissions do not allow this" do
+    it "should not load the pryrc if pryrc's directory permissions do not allow this", expect_failure: [:rbx] do
       Dir.mktmpdir do |dir|
         File.chmod 0000, dir
         Pry::LOCAL_RC_FILE.replace File.join(dir, '.pryrc')