From 5f24cb886d30b9410d8dba4babdd61914cb55c52 Mon Sep 17 00:00:00 2001
From: Markus Schirp <mbj@schirp-dso.com>
Date: Sun, 22 Nov 2020 04:20:37 +0000
Subject: [PATCH] Change Config inheritance to preserve order

---
 lib/mutant/cli/command/run.rb   |  4 ++--
 lib/mutant/config.rb            |  4 ++--
 spec/unit/mutant/cli_spec.rb    | 32 +++++++++++++++++++++++++-------
 spec/unit/mutant/config_spec.rb |  2 +-
 4 files changed, 30 insertions(+), 12 deletions(-)

diff --git a/lib/mutant/cli/command/run.rb b/lib/mutant/cli/command/run.rb
index 2c12ad112..7d262b980 100644
--- a/lib/mutant/cli/command/run.rb
+++ b/lib/mutant/cli/command/run.rb
@@ -35,7 +35,7 @@ def zombie?
 
         def initialize(attributes)
           super(attributes)
-          @config = Config::DEFAULT
+          @config = Config.env
         end
 
         def execute
@@ -49,7 +49,7 @@ def execute
         end
 
         def expand(file_config)
-          @config = Config.env.merge(file_config).merge(@config)
+          @config = @config.merge(file_config)
         end
 
         def soft_fail(result)
diff --git a/lib/mutant/config.rb b/lib/mutant/config.rb
index 2791bf155..16cc2afae 100644
--- a/lib/mutant/config.rb
+++ b/lib/mutant/config.rb
@@ -61,12 +61,12 @@ class Config
     def merge(other)
       other.with(
         fail_fast:        fail_fast || other.fail_fast,
-        includes:         includes + other.includes,
+        includes:         other.includes + includes,
         jobs:             other.jobs || jobs,
         integration:      other.integration || integration,
         mutation_timeout: other.mutation_timeout || mutation_timeout,
         matcher:          matcher.merge(other.matcher),
-        requires:         requires + other.requires,
+        requires:         other.requires + requires,
         zombie:           zombie || other.zombie
       )
     end
diff --git a/spec/unit/mutant/cli_spec.rb b/spec/unit/mutant/cli_spec.rb
index 40d6c5e5f..0f457686a 100644
--- a/spec/unit/mutant/cli_spec.rb
+++ b/spec/unit/mutant/cli_spec.rb
@@ -382,15 +382,14 @@ def self.make
       let(:env_result)         { instance_double(Mutant::Result::Env, success?: true) }
       let(:expected_events)    { [license_validation_event]                           }
       let(:expected_exit)      { true                                                 }
-      let(:file_config)        { Mutant::Config::DEFAULT                              }
       let(:file_config_result) { MPrelude::Either::Right.new(file_config)             }
       let(:license_result)     { MPrelude::Either::Right.new(subscription)            }
       let(:runner_result)      { MPrelude::Either::Right.new(env_result)              }
 
       let(:file_config) do
         Mutant::Config::DEFAULT.with(
-          includes: %w[lib],
-          requires: %w[foo]
+          includes: %w[include-file],
+          requires: %w[require-file]
         )
       end
 
@@ -557,15 +556,34 @@ def self.make
         end
 
         context 'with --include option' do
-          let(:arguments)        { super() + %w[--include lob --include lub] }
-          let(:bootstrap_config) { super().with(includes: %w[lib lob lub])   }
+          let(:arguments) do
+            super() + %w[
+              --include include-cli-a
+              --include include-cli-b
+            ]
+          end
+
+          let(:bootstrap_config) do
+            super().with(
+              includes: %w[
+                include-file
+                include-cli-a
+                include-cli-b
+              ]
+            )
+          end
 
           include_examples 'CLI run'
         end
 
         context 'with --require option' do
-          let(:arguments)        { super() + %w[--require bar]         }
-          let(:bootstrap_config) { super().with(requires: %w[foo bar]) }
+          let(:arguments) { super() + %w[--require require-cli] }
+
+          let(:bootstrap_config) do
+            super().with(
+              requires: %w[require-file require-cli]
+            )
+          end
 
           include_examples 'CLI run'
         end
diff --git a/spec/unit/mutant/config_spec.rb b/spec/unit/mutant/config_spec.rb
index 9a197e3da..e3f92d9ec 100644
--- a/spec/unit/mutant/config_spec.rb
+++ b/spec/unit/mutant/config_spec.rb
@@ -29,7 +29,7 @@ def expect_value(value)
       let(:original_value) { %w[bar] }
 
       it 'adds other and orignial' do
-        expect_value(original_value + other_value)
+        expect_value(other_value + original_value)
       end
     end