Add a spec for matching methods without source location

lib/mutant/env.rb

@@ -11,8 +11,8 @@ module Mutant
     #
     # @api private
     #
-    def self.new(config)
-      super(config, Cache.new)
+    def self.new(config, cache = Cache.new)
+      super(config, cache)
     end
 
     # Initialize env

spec/spec_helper.rb

@@ -30,7 +30,8 @@ $LOAD_PATH << File.join(TestApp.root, 'lib')
 require 'test_app'
 
 module Fixtures
-  BOOT_ENV = Mutant::Env.new(Mutant::Config::DEFAULT)
+  TEST_CACHE = Mutant::Cache.new
+  TEST_ENV   = Mutant::Env.new(Mutant::Config::DEFAULT, TEST_CACHE)
 end # Fixtures
 
 module ParserHelper

spec/unit/mutant/matcher/method/instance_spec.rb

@@ -3,7 +3,9 @@ require 'spec_helper'
 # rubocop:disable ClassAndModuleChildren
 describe Mutant::Matcher::Method::Instance do
 
-  let(:env) { Fixtures::BOOT_ENV }
+  let(:config)   { Mutant::Config::DEFAULT.update(reporter: reporter) }
+  let(:env)      { Mutant::Env.new(config, Fixtures::TEST_CACHE)      }
+  let(:reporter) { Mutant::Reporter::Trace.new                        }
 
   describe '#each' do
     subject { object.each { |subject| yields << subject } }
@@ -25,6 +27,21 @@ describe Mutant::Matcher::Method::Instance do
       node.children[1]
     end
 
+    context 'when method is defined without source location' do
+      let(:scope) { Module }
+      let(:method) { scope.instance_method(:object_id) }
+
+      it 'does not emit matcher' do
+        subject
+        expect(yields.length).to be(0)
+      end
+
+      it 'does warn' do
+        subject
+        expect(reporter.warn_calls.last).to eql('#<UnboundMethod: Module(Kernel)#object_id> does not have valid source location unable to emit matcher')
+      end
+    end
+
     context 'when method is defined once' do
       let(:base) { __LINE__ }
       class self::Foo

spec/unit/mutant/matcher/method/singleton_spec.rb

@@ -6,7 +6,7 @@ describe Mutant::Matcher::Method::Singleton, '#each' do
 
   let(:object)       { described_class.new(env, scope, method) }
   let(:method)       { scope.method(method_name)               }
-  let(:env)          { Fixtures::BOOT_ENV                      }
+  let(:env)          { Fixtures::TEST_ENV                      }
   let(:yields)       { []                                      }
   let(:namespace)    { self.class                              }
   let(:scope)        { self.class::Foo                         }

spec/unit/mutant/matcher/methods/instance_spec.rb

@@ -2,7 +2,7 @@ require 'spec_helper'
 
 describe Mutant::Matcher::Methods::Instance, '#each' do
   let(:object) { described_class.new(env, Foo) }
-  let(:env)    { Fixtures::BOOT_ENV            }
+  let(:env)    { Fixtures::TEST_ENV            }
 
   subject { object.each { |matcher| yields << matcher } }
 

spec/unit/mutant/matcher/methods/singleton_spec.rb

@@ -2,7 +2,7 @@ require 'spec_helper'
 
 describe Mutant::Matcher::Methods::Singleton, '#each' do
   let(:object) { described_class.new(env, Foo) }
-  let(:env)    { Fixtures::BOOT_ENV            }
+  let(:env)    { Fixtures::TEST_ENV            }
 
   subject { object.each { |matcher| yields << matcher } }