Test nested expressions

spec/ast/application_spec.rb

@@ -10,5 +10,25 @@ module Chervil
           .evaluate(env)
       ).to eq(3.0)
     end
+
+    it 'evaluates nested arithmetic' do
+      env = Env.new
+      expect(
+        AST::Application.new(
+          AST::Identifier.new('+'),
+          [
+            AST::Application.new(
+              AST::Identifier.new('+'),
+              [AST::Number.new(1.0), AST::Number.new(2.0)]
+            ),
+            AST::Application.new(
+              AST::Identifier.new('+'),
+              [AST::Number.new(3.0), AST::Number.new(4.0)]
+            )
+          ]
+        )
+          .evaluate(env)
+      ).to eq(10.0)
+    end
   end
 end

spec/parser_spec.rb

@@ -32,5 +32,29 @@ module Chervil
         AST::Definition.new(AST::Identifier.new('x'), AST::Number.new(5.0))
       )
     end
+
+    it 'parses a nested expression' do
+      expect(parse('(+ (+ 1 2) (- 3 4))').first).to eq(
+        AST::Application.new(
+          AST::Identifier.new("+"),
+          [
+            AST::Application.new(
+              AST::Identifier.new("+"),
+              [
+                AST::Number.new(1.0),
+                AST::Number.new(2.0),
+              ]
+            ),
+            AST::Application.new(
+              AST::Identifier.new("-"),
+              [
+                AST::Number.new(3.0),
+                AST::Number.new(4.0),
+              ]
+            ),
+          ]
+        )
+      )
+    end
   end
 end