+TypoHandling on objects in simple code

ConradIrwin · Mar 28, 2013 · e5e24e7 · e5e24e7
1 parent 7e41650
commit e5e24e7
Showing 1 changed file with 79 additions and 0 deletions.
diff --git a/lib/pry-rescue/autofix/method_typo.rb b/lib/pry-rescue/autofix/method_typo.rb
@@ -0,0 +1,79 @@
+require 'levenshtein'
+
+class PryRescue
+  class MethodTypo < Autofix
+
+    def suggestion
+      return unless exception.class == NoMethodError && missing_name && receiver_string && replacement
+      return "replace #{missing_name.inspect} by #{replacement.inspect}"
+    end
+
+    def fix!
+      edit_method do |old_text|
+        old_text.gsub(/\b#{Regexp.escape(missing_name)}\b/, replacement)
+      end
+
+      code = Pry::Code.from_method(Pry::Method.from_binding(bindings.first))
+      puts "\n#{code.with_line_numbers(true).to_s}\n"
+    end
+
+    private
+
+    def receiver
+      bindings.first.eval(receiver_string)
+    end
+
+    def receiver_string
+      $` if buggy_line =~ /\.#{Regexp.escape(missing_name)}/
+    end
+
+    def buggy_line
+      # TODO, handle (pry) properly
+      File.read(bindings.first.eval("__FILE__")).lines.to_a[bindings.first.eval("__LINE__") - 1]
+    end
+
+    def edit_method(&block)
+      MethodEditor.new(bindings.first, &block).perform_patch
+    end
+
+    def missing_name
+      exception.message[/\Aundefined method `([^']*)' for/, 1]
+    end
+
+    def replacement
+      @replacement ||=(
+        if scored_suggestions.any? && scored_suggestions.first.first < 2
+          scored_suggestions.first.last
+        end
+      )
+    end
+
+    def scored_suggestions
+      receiver_methods.map do |lvar|
+        [Levenshtein.distance(missing_name, lvar), lvar]
+      end.sort
+    end
+
+    def receiver_methods
+      r = begin
+            receiver or return []
+          rescue Pry::RescuableException
+            return []
+          end
+      Object.instance_method(:methods).bind(r).call(true).map(&:to_s) +
+      Object.instance_method(:private_methods).bind(r).call(true).map(&:to_s)
+    end
+  end
+end
+
+class MethodEditor < Pry::Command::Edit::MethodPatcher
+  def initialize(binding, &block)
+    @code_object = Pry::Method.from_binding(binding)
+    @_pry_ = Pry.new
+    @block = block
+  end
+
+  def patched_code
+    @patched_code ||= wrap(@block.call(adjusted_lines.join))
+  end
+end