commit

spec/expression_spec

@@ -1,130 +0,0 @@
-require "ruby_algebra"
-
-RSpec.configure do |config|
-  config.expect_with :rspec do |expectations|
-    expectations.include_chain_clauses_in_custom_matcher_descriptions = true
-  end
-end
-
-RSpec.describe RubyAlgebra do
-  describe "diff and evaluate" do
-    let(:x) { RubyAlgebra::Variable.new("x") }
-    let(:c) { RubyAlgebra::Constant.new(5) }
-
-    it "differentiates constant to 0" do
-      expr = RubyAlgebra::Constant.new(10)
-      derivative = expr.diff("x")
-      expect(derivative.evaluate).to eq 0
-    end
-
-    it "differentiates variable to 1" do
-      expr = RubyAlgebra::Variable.new("x")
-      derivative = expr.diff("x")
-      expect(derivative.evaluate).to eq 1
-    end
-
-    it "differentiates variable to 0 for different variable" do
-      expr = RubyAlgebra::Variable.new("x")
-      derivative = expr.diff("y")
-      expect(derivative.evaluate).to eq 0
-    end
-
-    it "differentiates sum" do
-      expr = RubyAlgebra::Addition.new(x, c)  
-      derivative = expr.diff("x")             
-      expect(derivative.evaluate).to eq 1
-    end
-
-    it "differentiates difference" do
-      expr = RubyAlgebra::Subtraction.new(x, c)  
-      derivative = expr.diff("x")                
-      expect(derivative.evaluate).to eq 1
-    end
-
-    it "differentiates product" do
-      expr = RubyAlgebra::Multiplication.new(x, x)  
-      derivative = expr.diff("x")                  
-      expr_at_3 = RubyAlgebra::Multiplication.new(
-        RubyAlgebra::Constant.new(2),
-        RubyAlgebra::Constant.new(3)
-      )
-      two_x = RubyAlgebra::Multiplication.new(
-        RubyAlgebra::Constant.new(2),
-        RubyAlgebra::Constant.new(3)
-      )
-      expect(two_x.evaluate).to eq 6
-    end
-
-    it "differentiates power with constant exponent" do
-      expr = RubyAlgebra::Power.new(x, RubyAlgebra::Constant.new(3))  
-      derivative = expr.diff("x")                                 
-      x_squared = RubyAlgebra::Power.new(
-        RubyAlgebra::Constant.new(2),
-        RubyAlgebra::Constant.new(2)
-      )
-      result = RubyAlgebra::Multiplication.new(
-        RubyAlgebra::Constant.new(3),
-        x_squared
-      )
-      expect(result.evaluate).to eq 12
-    end
-
-    it "evaluates constant expression" do
-      expr = RubyAlgebra::Addition.new(
-        RubyAlgebra::Constant.new(3),
-        RubyAlgebra::Constant.new(4)
-      )
-      expect(expr.evaluate).to eq 7
-    end
-
-    it "evaluates complex constant expression" do
-      expr = RubyAlgebra::Division.new(
-        RubyAlgebra::Addition.new(
-          RubyAlgebra::Multiplication.new(
-            RubyAlgebra::Constant.new(2),
-            RubyAlgebra::Constant.new(3)
-          ),
-          RubyAlgebra::Constant.new(4)
-        ),
-        RubyAlgebra::Constant.new(2)
-      )
-      expect(expr.evaluate).to eq 5
-    end
-
-    it "returns nil for expression with variable" do
-      expr = RubyAlgebra::Addition.new(
-        RubyAlgebra::Constant.new(5),
-        RubyAlgebra::Variable.new("x")
-      )
-      expect(expr.evaluate).to be_nil
-    end
-
-    it "checks constant? predicate" do
-      constant_expr = RubyAlgebra::Addition.new(
-        RubyAlgebra::Constant.new(2),
-        RubyAlgebra::Constant.new(3)
-      )
-      variable_expr = RubyAlgebra::Addition.new(
-        RubyAlgebra::Constant.new(2),
-        RubyAlgebra::Variable.new("x")
-      )
-      
-      expect(constant_expr).to be_constant
-      expect(variable_expr).not_to be_constant
-    end
-
-    it "differentiates complex expression" do
-      x_squared = RubyAlgebra::Power.new(x, RubyAlgebra::Constant.new(2))
-      three_x = RubyAlgebra::Multiplication.new(
-        RubyAlgebra::Constant.new(3),
-        x
-      )
-      inner = RubyAlgebra::Addition.new(x_squared, three_x)
-      expr = RubyAlgebra::Multiplication.new(inner, x)
-      
-      derivative = expr.diff("x")
-      expect(derivative).to be_a(RubyAlgebra::Expression)
-      expect(derivative.constant?).to be false
-    end
-  end
-end

spec/expression_spec.rb

@@ -0,0 +1,83 @@
+require 'rspec'
+require_relative '../lib/ruby_algebra/polynomial'
+require_relative '../lib/ruby_algebra/parser'
+
+RSpec.describe "RubyAlgebra Extended Suite" do
+  let(:x) { RubyAlgebra::Polynomial.new([RubyAlgebra::Term.new(1, { "x" => 1 })]) }
+  let(:y) { RubyAlgebra::Polynomial.new([RubyAlgebra::Term.new(1, { "y" => 1 })]) }
+
+  describe "Математические крайности (Edge Cases)" do
+    it "умножение на ноль дает пустой многочлен (0)" do
+      zero = RubyAlgebra::Polynomial.new([RubyAlgebra::Term.new(0)])
+      result = x * zero
+      expect(result.terms.reject { |t| t.coeff == 0 }).to be_empty
+    end
+
+    it "возведение в степень через умножение (x * x * x = x^3)" do
+      result = x * x * x
+      expect(result.terms.first.variables["x"]).to eq 3
+      expect(result.terms.first.coeff).to eq 1
+    end
+
+    it "сложение противоположных значений (x + (-x) = 0)" do
+      minus_x = x * -1
+      result = x + minus_x
+      expect(result.terms.reject { |t| t.coeff == 0 }).to be_empty
+    end
+  end
+
+  describe "Дифференцирование (Продвинутое)" do
+    it "производная от константы всегда 0" do
+      expr = RubyAlgebra::Polynomial.new([RubyAlgebra::Term.new(999)])
+      expect(expr.diff("x").terms.all? { |t| t.coeff == 0 }).to be true
+    end
+
+    it "вторая производная: diff(x^2) -> 2x, diff(2x) -> 2" do
+      first_der = (x * x).diff("x")
+      second_der = first_der.diff("x")
+      expect(second_der.terms.first.coeff).to eq 2
+      expect(second_der.terms.first.variables).to be_empty
+    end
+
+    it "частная производная: diff(x*y, 'x') -> y" do
+      expr = x * y
+      derivative = expr.diff("x")
+      expect(derivative.terms.first.variables).to eq({ "y" => 1 })
+      expect(derivative.terms.first.variables).not_to have_key("x")
+    end
+  end
+
+  describe "Подстановка (Substitution)" do
+    it "подстановка в многочлен с двумя переменными (x + y where x=1, y=2)" do
+      expr = x + y
+      # substitute принимает хеш значений
+      result = expr.substitute({ "x" => 1, "y" => 2 })
+      # Должно получиться 3 (константа)
+      expect(result.terms.first.coeff).to eq 3
+      expect(result.terms.first.variables).to be_empty
+    end
+
+    it "частичная подстановка (x*y where x=2) -> 2y" do
+      expr = x * y
+      result = expr.substitute({ "x" => 2 })
+      expect(result.terms.first.coeff).to eq 2
+      expect(result.terms.first.variables).to eq({ "y" => 1 })
+    end
+  end
+
+  describe "Строковое представление (to_s)" do
+    it "корректно отображает отрицательные коэффициенты" do
+      expr = x - 5
+      expect(expr.to_s).to eq "x - 5"
+    end
+
+    it "не пишет '1' перед переменной (x вместо 1x)" do
+      expect(x.to_s).to eq "x"
+    end
+
+    it "выводит '0', если многочлен пуст" do
+      zero_poly = RubyAlgebra::Polynomial.new([])
+      expect(zero_poly.to_s).to eq "0"
+    end
+  end
+end

spec/parser_spec.rb

@@ -138,7 +138,7 @@ RSpec.describe RubyAlgebra::Interpreter do
     cmd = RubyAlgebra::Parser.parse_command("Q, R := A / B")
     interpreter.execute(cmd)
     
-    expect(interpreter.execute(RubyAlgebra::Parser.parse_command("Q"))).to eq("1.0x + 1.0")
+    expect(interpreter.execute(RubyAlgebra::Parser.parse_command("Q"))).to eq("x + 1.0")
     expect(interpreter.execute(RubyAlgebra::Parser.parse_command("R"))).to eq("0")
   end
 end