Drew's solution

lib/tree.rb

@@ -1,25 +1,44 @@
 class NoApplesError < StandardError; end
 
-class AppleTree
-  attr_#fill_in :height, :age, :apples, :alive
+class Tree
+  attr_accessor :height, :age, :apples, :alive
 
   def initialize
+    @height=0
+    @age=0
+    @apples=[]
+    @alive=true
   end
 
   def age!
+    @age += 1
+    if @age > 50
+      @alive=false
+      return
+    end
+
+    @height += 1
+    self.add_apples
   end
 
   def add_apples
+    num_apples = rand(1..5) * @age + 1
+    num_apples.times do
+     @apples.push(Apple.new('red', rand(1..3)))
+    end
   end
 
   def any_apples?
+    @apples.size > 0
   end
 
   def pick_an_apple!
     raise NoApplesError, "This tree has no apples" unless self.any_apples?
+    @apples.pop
   end
 
   def dead?
+    not @alive
   end
 end
 
@@ -29,10 +48,12 @@ def initialize
   end
 end
 
-class Apple <
-  attr_reader #what should go here 
+class Apple < Fruit
+  attr_reader :color, :diameter
 
   def initialize(color, diameter)
+    @color=color
+    @diameter=diameter
   end
 end
 
@@ -61,7 +82,7 @@ def tree_data
       diameter_sum += apple.diameter
     end
 
-    avg_diameter = # It's up to you to calculate the average diameter for this harvest.
+    avg_diameter = basket.size > 0 ? diameter_sum / basket.size : 0
 
     puts "Year #{tree.age} Report"
     puts "Tree height: #{tree.height} feet"
@@ -76,4 +97,4 @@ def tree_data
 end
 
 # Uncomment this line to run the script, but BE SURE to comment it before you try to run your tests!
-# tree_data
+tree_data

spec/tree_spec.rb

@@ -2,13 +2,69 @@
 require 'tree'
 
 describe 'Tree' do
-  it 'should be a Class' do
-    expect(described_class.is_a? 'Class').to be_true
+  let(:tree) { Tree.new }
+
+  it 'should be a Tree' do
+    expect(tree.class).to be Tree
+  end
+
+  it 'should age' do
+    current_age = tree.age
+    tree.age!
+    new_age = tree.age
+    expect(new_age == current_age + 1).to be true
+  end
+
+  it 'should grow apples' do
+    current_apples = tree.apples.size
+    tree.add_apples
+    new_apples = tree.apples.size
+    expect(current_apples < new_apples).to be true
+  end
+
+  it 'should report if the tree has any apples' do
+    tree.add_apples
+    expect(tree.any_apples?).to be true
+  end
+
+  it 'should be able to have apples picked' do
+    10.times do
+      tree.add_apples
+    end
+    current_apples = tree.apples.size
+    tree.pick_an_apple!
+    new_apples = tree.apples.size
+    expect(new_apples == current_apples - 1).to be true
+  end
+
+  it 'should die after 50 years' do
+    51.times do
+      tree.age!
+    end
+    expect(tree.dead?).to be true
   end
 end
 
 describe 'Fruit' do
+  let(:fruit){Fruit.new}
+
+  it 'should be a Fruit' do
+    expect(fruit.class).to be Fruit
+  end
 end
 
 describe 'Apple' do
+  let(:apple){Apple.new('red', 2)}
+
+  it 'should be an Apple' do
+    expect(apple.class).to be Apple
+  end
+
+  it 'should be red' do
+    expect(apple.color == 'red').to be true
+  end
+
+  it 'should have diameter 2' do
+    expect(apple.diameter == 2).to be true
+  end
 end