diff --git a/src/spectator/line_example_filter.cr b/src/spectator/line_example_filter.cr
index 4063f34..0c65fba 100644
--- a/src/spectator/line_example_filter.cr
+++ b/src/spectator/line_example_filter.cr
@@ -7,13 +7,9 @@ module Spectator
 
     # Checks whether the example satisfies the filter.
     def includes?(example) : Bool
-      source = example.source
-      # end_line is present so there is a range to check against
-      if end_line = source.end_line
-        (source.line..end_line).covers?(@line)
-      else
-        source.line == @line
-      end
+      start_line = example.source.line
+      end_line = example.source.end_line
+      (start_line..end_line).covers?(@line)
     end
   end
 end
diff --git a/src/spectator/source.cr b/src/spectator/source.cr
index 699fb39..6afa3a7 100644
--- a/src/spectator/source.cr
+++ b/src/spectator/source.cr
@@ -4,15 +4,17 @@ module Spectator
     # Absolute file path.
     getter file : String
 
-    # Line number in the file.
-    # If end_line is present, this is the starting line
+    # Starting line number in the file.
     getter line : Int32
 
     # Ending line number in the file.
-    getter end_line : Int32?
+    getter end_line : Int32
 
     # Creates the source.
-    def initialize(@file, @line, @end_line = nil)
+    def initialize(@file, @line, end_line = nil)
+      # if an end line is not provided,
+      # make the end line the same as the start line
+      @end_line = end_line || @line
     end
 
     # Parses a source from a string.