RUBY-895 Check valid document in View#find and #projection

lib/mongo/collection/view.rb

@@ -125,6 +125,7 @@ def hash
       #
       # @since 2.0.0
       def initialize(collection, selector = {}, options = {})
+        validate_doc!(selector)
         @collection = collection
         @selector = selector.dup
         @options = options.dup

lib/mongo/collection/view/readable.rb

@@ -232,6 +232,7 @@ def no_cursor_timeout
         #
         # @since 2.0.0
         def projection(document = nil)
+          validate_doc!(document) if document
           configure(:projection, document)
         end
 
@@ -357,6 +358,10 @@ def special_selector
         def to_return
           [ limit || batch_size, batch_size || limit ].min
         end
+
+        def validate_doc!(doc)
+          raise Error::InvalidDocument.new unless doc.respond_to?(:keys)
+        end
       end
     end
   end

lib/mongo/error/invalid_document.rb

@@ -23,7 +23,7 @@ class InvalidDocument < Error
       # The error message.
       #
       # @since 2.0.0
-      MESSAGE = 'Invalid document provided'.freeze
+      MESSAGE = 'Invalid document provided.'.freeze
 
       # Instantiate the new exception.
       #

spec/mongo/collection/view/readable_spec.rb

@@ -436,11 +436,11 @@
 
   describe '#projection' do
 
-    context 'when projection are specified' do
+    let(:options) do
+      { :projection => { 'x' => 1 } }
+    end
 
-      let(:options) do
-        { :projection => { 'x' => 1 } }
-      end
+    context 'when projection are specified' do
 
       let(:new_projection) do
         { 'y' => 1 }
@@ -456,14 +456,25 @@
       end
     end
 
-    context 'when projection are not specified' do
-
-      let(:options) { { :projection => { 'x' => 1 } } }
+    context 'when projection is not specified' do
 
       it 'returns the projection' do
         expect(view.projection).to eq(options[:projection])
       end
     end
+
+    context 'when projection is not a document' do
+
+      let(:new_projection) do
+        'y'
+      end
+
+      it 'raises an error' do
+        expect do
+          view.projection(new_projection)
+        end.to raise_error(Mongo::Error::InvalidDocument)
+      end
+    end
   end
 
   describe '#read' do

spec/mongo/collection/view_spec.rb

@@ -496,6 +496,19 @@
     it 'dups the options' do
       expect(view.options).not_to be(options)
     end
+
+    context 'when the selector is not a valid document' do
+
+      let(:selector) do
+        'y'
+      end
+
+      it 'raises an error' do
+        expect do
+          view
+        end.to raise_error(Mongo::Error::InvalidDocument)
+      end
+    end
   end
 
   describe '#inspect' do