Fix check_symbol_to_proc false positives on lambda literals

lib/fasterer/method_call.rb

@@ -32,6 +32,10 @@ def arguments_element
       call_element[3..-1] || []
     end
 
+    def lambda_literal?
+      call_element.sexp_type == :lambda
+    end
+
     private
 
     attr_reader :call_element

lib/fasterer/scanners/method_call_scanner.rb

@@ -125,6 +125,7 @@ def check_symbol_to_proc
       return if method_call.block_body.nil?
       return unless method_call.block_body.sexp_type == :call
       return if method_call.arguments.count > 0
+      return if method_call.lambda_literal?
 
       body_method_call = MethodCall.new(method_call.block_body)
 

spec/lib/fasterer/analyzer/18_block_vs_symbol_to_proc_spec.rb

@@ -3,9 +3,9 @@
 describe Fasterer::Analyzer do
   let(:test_file_path) { RSpec.root.join('support', 'analyzer', '18_block_vs_symbol_to_proc.rb') }
 
-  it 'should block that could be called with symbol 7 times' do
+  it 'should block that could be called with symbol 9 times' do
     analyzer = Fasterer::Analyzer.new(test_file_path)
     analyzer.scan
-    expect(analyzer.errors[:block_vs_symbol_to_proc].count).to eq(7)
+    expect(analyzer.errors[:block_vs_symbol_to_proc].count).to eq(9)
   end
 end

spec/lib/fasterer/method_call_spec.rb

@@ -437,4 +437,36 @@
       # expect(method_call.receiver.name).to eq('hi')
     end
   end
+
+  describe '#lambda_literal?' do
+    describe 'lambda literal without arguments' do
+      let(:code) { '-> {}' }
+
+      let(:call_element) { ripper }
+
+      it 'should be true' do
+        expect(method_call).to be_lambda_literal
+      end
+    end
+
+    describe 'lambda literal with an argument' do
+      let(:code) { '->(_) {}' }
+
+      let(:call_element) { ripper }
+
+      it 'should be true' do
+        expect(method_call).to be_lambda_literal
+      end
+    end
+
+    describe 'lambda method' do
+      let(:code) { 'lambda {}' }
+
+      let(:call_element) { ripper }
+
+      it 'should be false' do
+        expect(method_call).not_to be_lambda_literal
+      end
+    end
+  end
 end

spec/support/analyzer/18_block_vs_symbol_to_proc.rb

@@ -37,3 +37,7 @@
 
 instance_eval { |_| method_call_without_receiver }
 instance_eval { |object| object.to_s }
+
+proc { |rule| rule.should_use_symbol }
+lambda { |rule| rule.should_use_symbol }
+->(obj) { obj.cannot_use_symbol }