Bugfix: Caching on subsequent redeploys (#948)

* Don't clear the cache on first app deploy

* Add output for debugging cache behavior

* Debug output of changes, clean up whitespace

* Update hatchet to use latest getting started guide

* Clean up caching output logs

This output was confusing and unhelptul to most users

* Changelog

* Test if we need these lines

* dang fi

* Remove unnecessary code

* Remove confusing output of change

* Update log output

* Update test to match new expected log output

* Update changelog

spec/hatchet/python_spec.rb

@@ -3,26 +3,40 @@ require_relative '../spec_helper'
 describe "Default Python Deploy" do
   it "🐍" do
     Hatchet::Runner.new('python-getting-started', stack: DEFAULT_STACK).deploy do |app|
+
+      # What should happen on first deploy
       expect(app.output).to           match(/Installing pip/)
-      expect(app.run('python -V')).to match(/3.6.10/)
 
+      # What should not happen
+      expect(app.output).to_not match("Requirements file has been changed, updating cache")
+      expect(app.output).to_not match("No change in requirements detected, installing from cache")
+      expect(app.output).to_not match("No such file or directory")
+      expect(app.output).to_not match("cp: cannot create regular file")
 
-      expect(app.output).to_not match("Clearing cached dependencies")
-
-      # Redeploy
+      # Redeploy with changed requirements file
+      run!(%Q{echo "" >> requirements.txt})
       run!(%Q{echo "flask" >> requirements.txt})
       run!(%Q{git add . ; git commit --allow-empty -m next})
       app.push!
 
-      # Check for the cache tohave cleared
-      expect(app.output).to match("Clearing cached dependencies")
+      # Check for the cache to have cleared
+      expect(app.output).to match("Requirements file has been changed, updating cache")
+
+      # What should not happen when the requirements file is changed
+      expect(app.output).to_not match("No dependencies found, preparing to install")
+      expect(app.output).to_not match("No change in requirements detected, installing from cache")
 
       run!(%Q{git commit --allow-empty -m next})
       app.push!
 
-      # The cache should not clear with no changes
-      expect(app.output).to_not match("Clearing cached dependencies")
+      # With no changes on redeploy, the cache should
+      expect(app.output).to match("No change in requirements detected, installing from cache")
 
+      # With no changes on redeploy, the cache should not
+      expect(app.output).to_not match("Requirements file has been changed, updating cache")
+      expect(app.output).to_not match("No dependencies found, preparing to install")
+
+      expect(app.run('python -V')).to match(/3.7.3/)
     end
   end
 end