Add support for parsing RSpec files (#94)

This PR adds support for parsing RSpec files correctly. Prior to this
PR, RSpec files would not get annotated correctly.

It adds support for files that use `RSpec.describe` and the `describe`
when it gets globally monkey patched.

Author: drwl

lib/annotate_rb/model_annotator/file_parser/custom_parser.rb

@@ -77,7 +77,38 @@ def on_class(const, _superclass, _bodystmt)
           super
         end
 
+        # Gets the `RSpec` opening in:
+        # ```ruby
+        # RSpec.describe "Collapsed::TestModel" do
+        #   # Deliberately left empty
+        # end
+        # ```
+        # receiver: "RSpec", operator: ".", method: "describe"
+        def on_command_call(receiver, operator, method, args)
+          add_event(__method__, receiver, lineno)
+          @block_starts << [receiver, lineno]
+
+          # We keep track of blocks using a stack
+          @_stack_code_block << receiver
+          super
+        end
+
         def on_method_add_block(method, block)
+          # When parsing a line with no explicit receiver, the method will be presented in an Array.
+          # It's not immediately clear why.
+          #
+          # Example:
+          # ```ruby
+          # describe "Collapsed::TestModel" do
+          #   # Deliberately left empty
+          # end
+          # ```
+          #
+          # => method = ["describe"]
+          if method.is_a?(Array) && method.size == 1
+            method = method.first
+          end
+
           add_event(__method__, method, lineno)
 
           if @_stack_code_block.last == method
@@ -125,6 +156,9 @@ def on_call(receiver, operator, message)
         def on_command(message, args)
           add_event(__method__, message, lineno)
           @block_starts << [message, lineno]
+
+          # We keep track of blocks using a stack
+          @_stack_code_block << message
           super
         end
 

spec/lib/annotate_rb/model_annotator/custom_parser_spec.rb

@@ -194,8 +194,8 @@ class Foo::User < ApplicationRecord
         FILE
       end
       let(:expected_comments) { [] }
-      let(:expected_starts) { [["FactoryBot", 0], ["factory", 1], ["admin", 2], ["factory", 3], ["FactoryBot", 4]] }
-      let(:expected_ends) { [["admin", 2], ["end", 3], ["end", 4]] }
+      let(:expected_starts) { [["FactoryBot", 0], ["factory", 1], ["admin", 2], ["FactoryBot", 4]] }
+      let(:expected_ends) { [["admin", 2], ["end", 3], ["factory", 3], ["end", 4]] }
 
       it "parses correctly" do
         check_it_parses_correctly
@@ -214,9 +214,9 @@ class Foo::User < ApplicationRecord
       end
       let(:expected_comments) { [] }
       let(:expected_starts) {
-        [["factory", 0], ["first_name", 1], ["last_name", 2], ["date_of_birth", 3], ["factory", 4]]
+        [["factory", 0], ["first_name", 1], ["last_name", 2], ["date_of_birth", 3]]
       }
-      let(:expected_ends) { [["first_name", 1], ["last_name", 2], ["date_of_birth", 3], ["end", 4]] }
+      let(:expected_ends) { [["first_name", 1], ["last_name", 2], ["date_of_birth", 3], ["end", 4], ["factory", 4]] }
 
       it "parses correctly" do
         check_it_parses_correctly
@@ -235,8 +235,44 @@ class Foo::User < ApplicationRecord
         FILE
       end
       let(:expected_comments) { [["# typed: strong", 0]] }
-      let(:expected_starts) { [["factory", 1], ["first_name", 2], ["last_name", 3], ["date_of_birth", 4], ["factory", 5]] }
-      let(:expected_ends) { [["first_name", 2], ["last_name", 3], ["date_of_birth", 4], ["end", 5]] }
+      let(:expected_starts) { [["factory", 1], ["first_name", 2], ["last_name", 3], ["date_of_birth", 4]] }
+      let(:expected_ends) { [["first_name", 2], ["last_name", 3], ["date_of_birth", 4], ["end", 5], ["factory", 5]] }
+
+      it "parses correctly" do
+        check_it_parses_correctly
+      end
+    end
+
+    context "when using an RSpec file" do
+      let(:input) do
+        <<~FILE
+          RSpec.describe "Collapsed::TestModel" do
+            # Deliberately left empty
+          end
+        FILE
+      end
+      let(:expected_comments) { [["# Deliberately left empty", 1]] }
+      let(:expected_starts) { [["RSpec", 0]] }
+      let(:expected_ends) { [["end", 2], ["RSpec", 2]] }
+
+      it "parses correctly" do
+        check_it_parses_correctly
+      end
+    end
+
+    context "when using an RSpec file with monkeypatching" do
+      # Should be removed by RSpec 4+
+      # https://github.com/rspec/rspec-core/issues/2301
+      let(:input) do
+        <<~FILE
+          describe "Collapsed::TestModel" do
+            # Deliberately left empty
+          end
+        FILE
+      end
+      let(:expected_comments) { [["# Deliberately left empty", 1]] }
+      let(:expected_starts) { [["describe", 0]] }
+      let(:expected_ends) { [["end", 2], ["describe", 2]] }
 
       it "parses correctly" do
         check_it_parses_correctly