Return nil if is not an actual file path

lib/irb/cmd/edit.rb

@@ -37,7 +37,7 @@ def execute(*args)
               # in this case, we should just ignore the error
             end
 
-          if source && File.exist?(source.file)
+          if source
             path = source.file
           else
             puts "Can not find file: #{path}"

lib/irb/cmd/show_source.rb

@@ -29,7 +29,7 @@ def execute(str = nil)
 
         source = SourceFinder.new(@irb_context).find_source(str)
 
-        if source && File.exist?(source.file)
+        if source
           show_source(source)
         else
           puts "Error: Couldn't locate a definition for #{str}"

lib/irb/source_finder.rb

@@ -34,16 +34,15 @@ def find_source(signature)
         method = Regexp.last_match[:method]
         file, line = receiver.method(method).source_location if receiver.respond_to?(method, true)
       end
-      if file && line
-        Source.new(file: file, first_line: line, last_line: find_end(file, line, @irb_context))
+      if file && line && File.exist?(file)
+        Source.new(file: file, first_line: line, last_line: find_end(file, line))
       end
     end
 
     private
 
-    def find_end(file, first_line, irb_context)
-      return first_line unless File.exist?(file)
-      lex = RubyLex.new(irb_context)
+    def find_end(file, first_line)
+      lex = RubyLex.new(@irb_context)
       lines = File.read(file).lines[(first_line - 1)..-1]
       tokens = RubyLex.ripper_lex_without_warning(lines.join)
       prev_tokens = []