Add tests that column information can be translated

actionview/lib/action_view/template/error.rb

@@ -157,6 +157,8 @@ class Error < ActionViewError # :nodoc:
       # Override to prevent #cause resetting during re-raise.
       attr_reader :cause
 
+      attr_reader :template
+
       def initialize(template)
         super($!.message)
         @cause = $!

actionview/lib/action_view/template/handlers/erb.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require "strscan"
+require "active_support/core_ext/string"
 
 module ActionView
   class Template
@@ -39,7 +40,7 @@ def handles_encoding?
         # source location inside the template.
         def translate_location(spot, backtrace_location, source)
           # Tokenize the source line
-          tokens = ERB::Util.tokenize(source.lines[backtrace_location.lineno - 1])
+          tokens = ::ERB::Util.tokenize(source.lines[backtrace_location.lineno - 1])
           new_first_column = find_offset(spot[:snippet], tokens, spot[:first_column])
           lineno_delta = spot[:first_lineno] - backtrace_location.lineno
           spot[:first_lineno] -= lineno_delta

actionview/test/fixtures/test/runtime_error.html.erb

@@ -0,0 +1,6 @@
+<h1>Oh no!</h1>
+This template has a runtime error
+<b>
+  <%= method_that_does_not_exist %>
+</b>
+Yikes!

actionview/test/template/render_test.rb

@@ -210,6 +210,29 @@ def test_render_outside_path
     end
   end
 
+  def test_render_runtime_error
+    skip unless RubyVM.respond_to?(:keep_script_lines)
+
+    # We need to enable this setting so that when we eval the template
+    # the compiled source is kept around.
+    setting = RubyVM.keep_script_lines
+    RubyVM.keep_script_lines = true
+
+    ex = assert_raises(ActionView::Template::Error) {
+      @view.render(template: "test/runtime_error")
+    }
+    erb_btl = ex.backtrace_locations.first
+
+    # Get the spot information from ErrorHighlight
+    spot = erb_btl.spot(ex.cause)
+    translated_spot = ex.template.translate_location(erb_btl, spot)
+    assert_equal 6, translated_spot[:first_column]
+  ensure
+    if RubyVM.respond_to?(:keep_script_lines)
+      RubyVM.keep_script_lines = setting
+    end
+  end
+
   def test_render_partial
     assert_equal "only partial", @view.render(partial: "test/partial_only")
   end