Check for version from last build and remove build directories if the…

… versions does not match

fixes #52

lib/epuber/command.rb

@@ -74,5 +74,14 @@ def write_lockfile
         Epuber::Config.instance.save_lockfile
       end
     end
+
+    def pre_build_checks
+      Config.instance.warn_for_outdated_versions!
+
+      if !Config.instance.same_version_as_last_run? && File.exist?(Config.instance.working_path)
+        UI.warning('Using different version of Epuber or Bade, removing all build caches')
+        Config.instance.remove_build_caches
+      end
+    end
   end
 end

lib/epuber/command/build.rb

@@ -45,7 +45,7 @@ def validate!
         verify_one_bookspec_exists!
         verify_all_targets_exists!
 
-        Config.instance.warn_for_outdated_versions!
+        pre_build_checks
       end
 
       def run

lib/epuber/command/server.rb

@@ -30,7 +30,7 @@ def validate!
         super
         verify_one_bookspec_exists!
 
-        Config.instance.warn_for_outdated_versions!
+        pre_build_checks
       end
 
       def run

lib/epuber/config.rb

@@ -131,6 +131,18 @@ def warn_for_outdated_versions!
       end
     end
 
+    def same_version_as_last_run?
+      !(bookspec_lockfile.epuber_version != Epuber::VERSION ||
+          bookspec_lockfile.bade_version.nil? ||
+          bookspec_lockfile.bade_version != Bade::VERSION)
+    end
+
+    def remove_build_caches
+      FileUtils.rm_rf(File.join(working_path, 'build_cache'))
+      FileUtils.rm_rf(File.join(working_path, 'build'))
+      FileUtils.rm_rf(File.join(working_path, 'metadata'))
+    end
+
     # ---------------------------------------------------------------------------------------------------------------- #
 
     class << self

spec/unit/config_spec.rb

@@ -7,9 +7,11 @@ module Epuber
   describe Config do
     include FakeFS::SpecHelpers
 
-    it "warns if the previous version of Epuber is newer" do
+    before do
       Config.clear_instance!
+    end
 
+    it "warns if the previous version of Epuber is newer" do
       lockfile = {
           'epuber_version' => '200000.0.0',
           'bade_version' => Bade::VERSION,
@@ -24,8 +26,6 @@ module Epuber
     end
 
     it "warns if the previous version of Bade is newer" do
-      Config.clear_instance!
-
       lockfile = {
           'epuber_version' => Epuber::VERSION,
           'bade_version' => '200000.0.0',
@@ -40,8 +40,6 @@ module Epuber
     end
 
     it "is backward compatible" do
-      Config.clear_instance!
-
       lockfile = {
           'version' => '0.1',
       }
@@ -58,11 +56,52 @@ module Epuber
     end
 
     it "is working when there is no lockfile yet" do
-      Config.clear_instance!
-
       File.write('some.bookspec', '')
 
       expect(Config.instance.bookspec_lockfile.epuber_version).to_not be_nil
     end
+
+    context '#diff_version_from_last_build?' do
+      it 'detects when using different version of Epuber or Bade' do
+        lockfile = {
+            'epuber_version' => '200000.0.0',
+            'bade_version' => '200000.0.0',
+        }
+
+        File.write('some.bookspec', '')
+        File.write('some.bookspec.lock', lockfile.to_yaml)
+
+        expect(Config.instance.same_version_as_last_run?).to be_falsey
+      end
+
+      it 'detects when using same versions of Epuber and Bade' do
+        lockfile = {
+            'epuber_version' => Epuber::VERSION,
+            'bade_version' => Bade::VERSION,
+        }
+
+        File.write('some.bookspec', '')
+        File.write('some.bookspec.lock', lockfile.to_yaml)
+
+        expect(Config.instance.same_version_as_last_run?).to be_truthy
+      end
+
+      it 'is backward compatible' do
+        lockfile = {
+            'version' => '0.1',
+        }
+
+        File.write('some.bookspec', '')
+        File.write('some.bookspec.lock', lockfile.to_yaml)
+
+        expect(Config.instance.same_version_as_last_run?).to be_falsey
+      end
+
+      it 'is working when there is no lockfile yet' do
+        File.write('some.bookspec', '')
+
+        expect(Config.instance.same_version_as_last_run?).to_not be_falsey
+      end
+    end
   end
 end