class RSpec::Core::Formatters::SnippetExtractor
@api private
Extracts code snippets by looking at the backtrace of the passed error and applies synax highlighting and line numbers using html.
Public Instance Methods
@api private
Extract lines of code centered around a particular line within a source file.
@param [String] file filename @param [Fixnum] line line number @return [String] lines around the target line within the file (2 above and 1 below).
# File lib/rspec/core/formatters/snippet_extractor.rb, line 57 def lines_around(file, line) if File.file?(file) lines = File.read(file).split("\n") min = [0, line-3].max max = [line+1, lines.length-1].min selected_lines = [] selected_lines.join("\n") lines[min..max].join("\n") else "# Couldn't get snippet for #{file}" end rescue SecurityError "# Couldn't get snippet for #{file}" end
@api private
Adds line numbers to all lines and highlights the line where the failure occurred using html `span` tags.
@param [String] highlighted syntax-highlighted snippet surrounding the offending line of code @param [Fixnum] offending_line line where failure occured @return [String] completed snippet
# File lib/rspec/core/formatters/snippet_extractor.rb, line 79 def post_process(highlighted, offending_line) new_lines = [] highlighted.split("\n").each_with_index do |line, i| new_line = "<span class=\"linenum\">#{offending_line+i-2}</span>#{line}" new_line = "<span class=\"offending\">#{new_line}</span>" if i == 2 new_lines << new_line end new_lines.join("\n") end
@api private
Extract lines of code corresponding to a backtrace.
@param [String] backtrace the backtrace from a test failure @return [String] highlighted code snippet indicating where the test failure occured
@see post_process
# File lib/rspec/core/formatters/snippet_extractor.rb, line 25 def snippet(backtrace) raw_code, line = snippet_for(backtrace[0]) highlighted = @@converter.convert(raw_code, false) highlighted << "\n<span class=\"comment\"># gem install syntax to get syntax highlighting</span>" if @@converter.is_a?(NullConverter) post_process(highlighted, line) end
@api private
Create a snippet from a line of code.
@param [String] error_line file name with line number (i.e. 'foo_spec.rb:12') @return [String] lines around the target line within the file
@see lines_around
# File lib/rspec/core/formatters/snippet_extractor.rb, line 40 def snippet_for(error_line) if error_line =~ /(.*):(\d+)/ file = $1 line = $2.to_i [lines_around(file, line), line] else ["# Couldn't get snippet for #{error_line}", 1] end end