Prefer runtime env values over .env values

Gemfile

@@ -5,6 +5,7 @@ gemspec
 gem 'thor', '0.19.4', :require => false
 
 group :test do
+  gem 'climate_control'
   gem 'rake'
   gem 'fakefs'
   gem 'rspec',  '~> 3.5'

lib/foreman/cli.rb

@@ -37,6 +37,7 @@ def is_thor_reserved_word?(word, type)
   def start(process=nil)
     check_procfile!
     load_environment!
+    inherit_environment!
     engine.load_procfile(procfile)
     engine.options[:formation] = "#{process}=1" if process
     engine.start
@@ -80,6 +81,7 @@ def check
 
   def run(*args)
     load_environment!
+    inherit_environment!
 
     if File.file?(procfile)
       engine.load_procfile(procfile)
@@ -134,6 +136,10 @@ def check_procfile!
     error("#{procfile} does not exist.") unless File.file?(procfile)
   end
 
+  def inherit_environment!
+    engine.inherit_env
+  end
+
   def load_environment!
     if options[:env]
       options[:env].split(",").each do |file|

lib/foreman/engine.rb

@@ -172,12 +172,26 @@ def load_procfile(filename)
     self
   end
 
+  # Load ENV into the +env+ for this +Engine+
+  #
+  def inherit_env
+    merge_env(ENV)
+  end
+
   # Load a .env file into the +env+ for this +Engine+
   #
   # @param [String] filename  A .env file to load into the environment
   #
   def load_env(filename)
-    Foreman::Env.new(filename).entries do |name, value|
+    merge_env(Foreman::Env.new(filename).entries)
+  end
+
+  # Load a hash or entries list into the +env+ for this +Engine+
+  #
+  # @param [Hash] entries  A Hash or an entries list to load into the environment
+  #
+  def merge_env(entries)
+    entries.each do |name, value|
       @env[name] = value
     end
   end

lib/foreman/env.rb

@@ -19,11 +19,4 @@ def initialize(filename)
       ax
     end
   end
-
-  def entries
-    @entries.each do |key, value|
-      yield key, value
-    end
-  end
-
 end

spec/foreman/cli_spec.rb

@@ -88,6 +88,12 @@
       expect(forked_foreman("run -e #{resource_path(".env")} #{resource_path("bin/env FOO")}")).to eq("bar\n")
     end
 
+    it "prefers ENV to .env" do
+      ClimateControl.modify FOO: 'qux' do
+        expect(forked_foreman("run -e #{resource_path(".env")} #{resource_path("bin/env FOO")}")).to eq("qux\n")
+      end
+    end
+
     it "can run a command from the Procfile" do
       expect(forked_foreman("run -f #{resource_path("Procfile")} test")).to eq("testing\n")
     end

spec/foreman/engine_spec.rb

@@ -61,6 +61,13 @@ def shutdown
   end
 
   describe "environment" do
+    it "should read ENV" do
+      ClimateControl.modify FOO: 'baz' do
+        subject.inherit_env
+        expect(subject.env["FOO"]).to eq("baz")
+      end
+    end
+
     it "should read env files" do
       write_file("/tmp/env") { |f| f.puts("FOO=baz") }
       subject.load_env("/tmp/env")
@@ -76,6 +83,14 @@ def shutdown
       expect(subject.env["BAZ"]).to eq("qux")
     end
 
+    it "should prefer later versions of values" do
+      write_file("/tmp/env1") { |f| f.puts("FOO=bar") }
+      write_file("/tmp/env2") { |f| f.puts("FOO=qux") }
+      subject.load_env "/tmp/env1"
+      subject.load_env "/tmp/env2"
+      expect(subject.env["FOO"]).to eq("qux")
+    end
+
     it "should handle quoted values" do
       write_file("/tmp/env") do |f|
         f.puts 'FOO=bar'

spec/spec_helper.rb

@@ -8,6 +8,7 @@
 require "pp"
 require "fakefs/safe"
 require "fakefs/spec_helpers"
+require 'climate_control'
 
 $:.unshift File.expand_path("../../lib", __FILE__)