function_spec.rb in danica-2.6.3

- old
+ new

@@ -32,10 +32,40 @@
     described_class.build(*variables) do
       Danica::Operator::Power.new(x, y)
     end
   end
 
+  describe '.for' do
+    let(:expression_class) { Danica::Expression::Gauss }
+    let(:expression) { expression_class.new }
+    subject do
+      described_class.for(expression_class).new
+    end
+
+    it 'returns a function' do
+      expect(subject).to be_a(described_class)
+    end
+
+    it 'behaves like a function' do
+      expect do
+        subject.to_tex
+      end.not_to raise_error
+    end
+
+    it 'creates a funcion out of an expression' do
+      expect(subject.to_tex).to eq("f(x, \\mu, \\sigma) = #{expression.to_tex}")
+    end
+
+    context 'when passing an operator' do
+      let(:expression_class) { Danica::Operator::Cos }
+
+      it do
+        expect(subject.to_tex).to eq("f(value) = #{expression.to_tex}")
+      end
+    end
+  end
+
   describe '.build' do
     let(:function) do
       function_class.new(name: :f)
     end
 
@@ -50,11 +80,11 @@
         expect(function_class.superclass).to eq(described_class)
       end
     end
 
     context 'when creating a class using build' do
-      let(:function_class) { Danica::Function::Hyperbole }
+      let(:function_class) { Danica::Function::Parabole }
 
       it 'has the defined variables on class definition' do
         expect(function_class.variables_names).to eq([:x])
       end
 
@@ -74,10 +104,10 @@
         end
       end
     end
 
     context 'when using a class that inherits from another class' do
-      let(:function_class) { Danica::Function::SaddleHyperbole }
+      let(:function_class) { Danica::Function::SaddleParabole }
 
       it 'has the defined variables on class definition' do
         expect(function_class.variables_names).to eq([:x, :y])
       end
 