WIP

lib/nanoc/base/entities/directed_graph.rb

@@ -48,6 +48,7 @@ def initialize(vertices)
       @roots = Set.new(@vertices.keys)
 
       invalidate_caches
+      check_invariants
     end
 
     # @group Modifying the graph
@@ -76,6 +77,7 @@ def add_edge(from, to, props: nil)
       @roots.delete(to)
 
       invalidate_caches
+      check_invariants
     end
 
     # Removes the edge from the first vertex to the second vertex. If the
@@ -98,6 +100,7 @@ def delete_edge(from, to)
       @roots.add(to) if @to_graph[to].empty?
 
       invalidate_caches
+      check_invariants
     end
 
     # Adds the given vertex to the graph.
@@ -111,6 +114,8 @@ def add_vertex(v)
       @vertices[v] = @vertices.size
 
       @roots << v
+
+      check_invariants
     end
 
     # Deletes all edges coming from the given vertex.
@@ -127,6 +132,8 @@ def delete_edges_from(from)
         @roots.add(to) if @to_graph[to].empty?
       end
       @from_graph.delete(from)
+
+      check_invariants
     end
 
     # Deletes all edges going to the given vertex.
@@ -143,6 +150,20 @@ def delete_edges_to(to)
       end
       @to_graph.delete(to)
       @roots.add(to)
+
+      check_invariants
+    end
+
+    def check_invariants
+      @vertices.each do |(k, v)|
+        unless v
+          raise "Internal inconsistency: idx for vertex #{k.inspect} is nil (I)"
+        end
+
+        unless @vertices[k]
+          raise "Internal inconsistency: idx for vertex #{k.inspect} is nil (II)"
+        end
+      end
     end
 
     # Removes the given vertex from the graph.
@@ -156,6 +177,8 @@ def delete_vertex(v)
 
       @vertices.delete(v)
       @roots.delete(v)
+
+      check_invariants
     end
 
     # @group Querying the graph
@@ -246,6 +269,8 @@ def props_for(from, to)
 
     # @return [Array] The list of all vertices in this graph.
     def vertices
+      check_invariants
+
       @vertices.keys.sort_by { |v| @vertices[v] }
     end
 

lib/nanoc/base/entities/document.rb

@@ -86,11 +86,6 @@ def inspect
         "<#{self.class} identifier=\"#{identifier}\">"
       end
 
-      contract C::None => C::Num
-      def hash
-        self.class.hash ^ identifier.hash
-      end
-
       contract C::Any => C::Bool
       def ==(other)
         other.respond_to?(:identifier) && identifier == other.identifier

spec/nanoc/base/entities/document_spec.rb

@@ -178,21 +178,13 @@
       let(:identifier_arg_b) { '/home.md' }
 
       it { is_expected.to eql(true) }
-
-      it 'has same hashes' do
-        expect(document_a.hash).to eql(document_b.hash)
-      end
     end
 
     context 'different identifier' do
       let(:identifier_arg_a) { '/home.md' }
       let(:identifier_arg_b) { '/about.md' }
 
       it { is_expected.to eql(false) }
-
-      it 'has different hashes' do
-        expect(document_a.hash).not_to eql(document_b.hash)
-      end
     end
 
     context 'comparing with non-document' do