(GH-26) Remove the use of Pathname

While Pathname is a great utility it is not supported cross platform

> ... however non-Unix pathnames are supported experimentally. ... [1]

This commit changes;
* The usage of Pathname back to core Dir and File classes
* Adds a helper method dir_exists? to make testing easier
* Fixes the file_exist? method to check if the thing that exists is actually
  not a directory
* Adds tests to ensure the directory traversing terminates correctly

[1] http://ruby-doc.org/stdlib-2.1.9/libdoc/pathname/rdoc/Pathname.html

Author: glennsarti

lib/puppet-languageserver/document_store.rb

@@ -84,25 +84,28 @@ def self.store_has_puppetfile?
     # root of the module/control repo actually is
     def self.find_root_path(path)
       return nil if path.nil?
+      filepath = File.expand_path(path)
 
-      filepath = Pathname.new(path).expand_path
-      return nil unless filepath.exist?
-
-      if filepath.directory?
+      if dir_exist?(filepath)
         directory = filepath
+      elsif file_exist?(filepath)
+        directory = File.dirname(filepath)
       else
-        directory = filepath.dirname
+        return nil
       end
 
-      root_path = nil
-      directory.ascend do |p|
-        if file_exist?(p.join('metadata.json')) || file_exist?(p.join('Puppetfile'))
-          root_path = p.to_s
-          break
+      until directory.nil?
+        break if file_exist?(File.join(directory, 'metadata.json')) || file_exist?(File.join(directory, 'Puppetfile'))
+        parent = File.dirname(directory)
+        # If the parent is the same as the original, then we've reached the end of the path chain
+        if parent == directory
+          directory = nil
+        else
+          directory = parent
         end
       end
 
-      root_path
+      directory
     end
     private_class_method :find_root_path
 
@@ -140,8 +143,13 @@ def self.store_details
     private_class_method :store_details
 
     def self.file_exist?(path)
-      File.exist?(path)
+      File.exist?(path) && !File.directory?(path)
     end
     private_class_method :file_exist?
+
+    def self.dir_exist?(path)
+      Dir.exist?(path)
+    end
+    private_class_method :dir_exist?
   end
 end

spec/languageserver/integration/puppet-languageserver/document_store_spec.rb

@@ -47,7 +47,7 @@
 
   RSpec.shared_examples 'a cached workspace' do
     it 'should cache the information' do
-      expect(subject).to receive(:file_exist?).at_least(:once)
+      expect(subject).to receive(:file_exist?).at_least(:once).and_call_original
       result = PuppetLanguageServer::DocumentStore.store_root_path
       # Subsequent calls should be cached
       expect(subject).to receive(:file_exist?).exactly(0).times
@@ -60,7 +60,7 @@
       result = PuppetLanguageServer::DocumentStore.store_root_path
       # Expire the cache
       PuppetLanguageServer::DocumentStore.expire_store_information
-      expect(subject).to receive(:file_exist?).at_least(:once)
+      expect(subject).to receive(:file_exist?).at_least(:once).and_call_original
       result = PuppetLanguageServer::DocumentStore.store_root_path
       # Subsequent calls should be cached
       expect(subject).to receive(:file_exist?).exactly(0).times
@@ -70,6 +70,15 @@
     end
   end
 
+  RSpec.shared_examples 'a terminating file finder' do |expected_file_calls, expected_dir_calls|
+    it 'should only traverse until it finds an expected file' do
+      # TODO: This test is a little fragile but can't think of a better way to prove it
+      expect(subject).to receive(:file_exist?).exactly(expected_file_calls).times.and_call_original
+      expect(subject).to receive(:dir_exist?).exactly(expected_dir_calls).times.and_call_original
+      result = PuppetLanguageServer::DocumentStore.store_root_path
+    end
+  end
+
   # Empty or missing workspace
   context 'given a workspace option which is nil' do
     let(:server_options) { {} }
@@ -121,6 +130,7 @@
 
     it_should_behave_like 'a puppetfile workspace', expected_root
     it_should_behave_like 'a cached workspace'
+    it_should_behave_like 'a terminating file finder', 4, 1
   end
 
   context 'given a workspace option which has a parent directory with a puppetfile' do
@@ -135,6 +145,7 @@
 
     it_should_behave_like 'a puppetfile workspace', expected_root
     it_should_behave_like 'a cached workspace'
+    it_should_behave_like 'a terminating file finder', 8, 1
   end
 
   # Module metadata style workspaces
@@ -149,6 +160,7 @@
 
     it_should_behave_like 'a metadata.json workspace', expected_root
     it_should_behave_like 'a cached workspace'
+    it_should_behave_like 'a terminating file finder', 3, 1
   end
 
   context 'given a workspace option which has a parent directory with metadata.json' do
@@ -163,5 +175,6 @@
 
     it_should_behave_like 'a metadata.json workspace', expected_root
     it_should_behave_like 'a cached workspace'
+    it_should_behave_like 'a terminating file finder', 5, 1
   end
 end