1 files changed, 95 insertions, 0 deletions
diff --git a/spec/syntax_suggest/unit/priority_queue_spec.rb b/spec/syntax_suggest/unit/priority_queue_spec.rb
new file mode 100644
index 0000000000..17361833e5
--- /dev/null
+++ b/spec/syntax_suggest/unit/priority_queue_spec.rb
@@ -0,0 +1,95 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+module SyntaxSuggest
+  class CurrentIndex
+    attr_reader :current_indent
+
+    def initialize(value)
+      @current_indent = value
+    end
+
+    def <=>(other)
+      @current_indent <=> other.current_indent
+    end
+
+    def inspect
+      @current_indent
+    end
+  end
+
+  RSpec.describe CodeFrontier do
+    it "works" do
+      q = PriorityQueue.new
+      q << 1
+      q << 2
+      expect(q.elements).to eq([2, 1])
+
+      q << 3
+      expect(q.elements).to eq([3, 1, 2])
+
+      expect(q.pop).to eq(3)
+      expect(q.pop).to eq(2)
+      expect(q.pop).to eq(1)
+      expect(q.pop).to eq(nil)
+
+      array = []
+      q = PriorityQueue.new
+      array.reverse_each do |v|
+        q << v
+      end
+      expect(q.elements).to eq(array)
+
+      array = [100, 36, 17, 19, 25, 0, 3, 1, 7, 2]
+      array.reverse_each do |v|
+        q << v
+      end
+
+      expect(q.pop).to eq(100)
+      expect(q.elements).to eq([36, 25, 19, 17, 0, 1, 7, 2, 3])
+
+      # expected [36, 25, 19, 17, 0, 1, 7, 2, 3]
+      expect(q.pop).to eq(36)
+      expect(q.pop).to eq(25)
+      expect(q.pop).to eq(19)
+      expect(q.pop).to eq(17)
+      expect(q.pop).to eq(7)
+      expect(q.pop).to eq(3)
+      expect(q.pop).to eq(2)
+      expect(q.pop).to eq(1)
+      expect(q.pop).to eq(0)
+      expect(q.pop).to eq(nil)
+    end
+
+    it "priority queue" do
+      frontier = PriorityQueue.new
+      frontier << CurrentIndex.new(0)
+      frontier << CurrentIndex.new(1)
+
+      expect(frontier.sorted.map(&:current_indent)).to eq([0, 1])
+
+      frontier << CurrentIndex.new(1)
+      expect(frontier.sorted.map(&:current_indent)).to eq([0, 1, 1])
+
+      frontier << CurrentIndex.new(0)
+      expect(frontier.sorted.map(&:current_indent)).to eq([0, 0, 1, 1])
+
+      frontier << CurrentIndex.new(10)
+      expect(frontier.sorted.map(&:current_indent)).to eq([0, 0, 1, 1, 10])
+
+      frontier << CurrentIndex.new(2)
+      expect(frontier.sorted.map(&:current_indent)).to eq([0, 0, 1, 1, 2, 10])
+
+      frontier = PriorityQueue.new
+      values = [18, 18, 0, 18, 0, 18, 18, 18, 18, 16, 18, 8, 18, 8, 8, 8, 16, 6, 0, 0, 16, 16, 4, 14, 14, 12, 12, 12, 10, 12, 12, 12, 12, 8, 10, 10, 8, 8, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 8, 10, 6, 6, 6, 6, 6, 6, 8, 10, 8, 8, 10, 8, 10, 8, 10, 8, 6, 8, 8, 6, 8, 6, 6, 8, 0, 8, 0, 0, 8, 8, 0, 8, 0, 8, 8, 0, 8, 8, 8, 0, 8, 0, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 6, 8, 6, 6, 6, 6, 8, 6, 8, 6, 6, 4, 4, 6, 6, 4, 6, 4, 6, 6, 4, 6, 4, 4, 6, 6, 6, 6, 4, 4, 4, 2, 4, 4, 4, 4, 4, 4, 6, 6, 0, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 0, 0, 6, 6, 2]
+
+      values.each do |v|
+        value = CurrentIndex.new(v)
+        frontier << value # CurrentIndex.new(v)
+      end
+
+      expect(frontier.sorted.map(&:current_indent)).to eq(values.sort)
+    end
+  end
+end