Scan method body for file

test/coverband/utils/method_definition_test.rb

@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+require File.expand_path('../../test_helper', File.dirname(__FILE__))
+
+module Coverband
+  module Utils
+    class MethodDefinition
+      attr_reader :path
+      def initialize(path)
+        @path = path
+      end
+
+      def scan
+        scan_node(RubyVM::AbstractSyntaxTree.parse_file(path))
+      end
+
+      def self.scan(path)
+        MethodDefinition.new(path).scan
+      end
+
+      private
+
+      def scan_node(node)
+        return [] unless node.is_a?(RubyVM::AbstractSyntaxTree::Node)
+        definitions = []
+        if node.type == :DEFN
+          definitions <<
+            OpenStruct.new(
+              first_line_number: node.first_lineno,
+              last_line_number: node.last_lineno
+            )
+        end
+        definitions +
+          node.children.flatten.compact.map { |child| scan_node(child) }.flatten
+      end
+    end
+
+    class MethodDefinitionTest < Minitest::Test
+      def test_scan
+        method_definitions = MethodDefinition.scan('./test/dog.rb')
+        assert(method_definitions)
+        assert_equal(1, method_definitions.length)
+        method_definition = method_definitions.first # assert_equal(4, method.first_line)
+        assert_equal(4, method_definition.first_line_number)
+        assert_equal(6, method_definition.last_line_number)
+      end
+    end
+  end
+end