add all? to SortedArray

lib/sorted_containers/sorted_array.rb

@@ -180,6 +180,21 @@ def abbrev(pattern = nil)
       to_a.abbrev(pattern)
     end
 
+    # Returns true if all elements of self meet the given criterion.
+    # If the block is not given, returns true if all elements are truthy.
+    # If self is empty, returns true.
+    #
+    # @yield [value] The block to check with.
+    # @return [Boolean] True if all elements meet the given criterion, false otherwise.
+    def all?
+      if block_given?
+        each { |value| return false unless yield(value) }
+      else
+        each { |value| return false unless value }
+      end
+      true
+    end
+
     # Returns a string representation of the sorted array.
     #
     # @return [String] A string representation of the sorted array.

spec/sorted_array_spec.rb

@@ -262,6 +262,33 @@
     end
   end
 
+  describe "all?" do
+    it "should return true if all elements meet a given criterion" do
+      array = SortedContainers::SortedArray.new([1, 2, 3, 4, 5])
+      expect(array.all? { |i| i > 0 }).to be true
+    end
+
+    it "should return false if all elements do not meet a given criterion" do
+      array = SortedContainers::SortedArray.new([1, 2, 3, 4, 5])
+      expect(array.all? { |i| i > 1 }).to be false
+    end
+
+    it "should return true if the array contains only truthy elements" do
+      array = SortedContainers::SortedArray.new([1, 2, 3, 4, 5])
+      expect(array.all?).to be true
+    end
+
+    it "should return false if the array contains a falsy element" do
+      array = SortedContainers::SortedArray.new([false, false])
+      expect(array.all?).to be false
+    end
+
+    it "should return true if the array is empty" do
+      array = SortedContainers::SortedArray.new
+      expect(array.all?).to be true
+    end
+  end
+
   describe "load_factor" do
     it "should set the load factor to the provided value" do
       array = SortedContainers::SortedArray.new([], load_factor: 100)