Raise error on failure of force_install

Author: ianfixes

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Changed
 - Simplified the use of `Array.each` with a return statement; it's now simply `Array.find`
+- `autolocate!` for Arduino installations now raises `ArduinoInstallationError` if `force_install` fails
 
 ### Deprecated
 

lib/arduino_ci/arduino_downloader.rb

@@ -186,7 +186,7 @@ def execute
       elsif File.exist? extracted_file
         install
       else
-        puts "Arduino force-install failed"
+        puts "Could not find extracted archive (tried #{extracted_file})"
       end
 
       File.exist? self.class.force_install_location

lib/arduino_ci/arduino_installation.rb

@@ -13,6 +13,8 @@
 
 module ArduinoCI
 
+  class ArduinoInstallationError < StandardError; end
+
   # Manage the OS-specific install location of Arduino
   class ArduinoInstallation
 
@@ -94,7 +96,8 @@ def autolocate!
         return candidate unless candidate.nil?
 
         # force the install
-        force_install
+        raise ArduinoInstallationError, "Failed to force-install Arduino" unless force_install
+
         autolocate
       end