# frozen_string_literal: true require_relative 'helper' require 'tempfile' separate_testing do require_relative '../lib/rack/lint' require_relative '../lib/rack/mock_request' end describe Rack::Lint do valid_app = lambda do |env| [200, { "content-type" => "test/plain", "content-length" => "3" }, ["foo"]] end def env(*args) Rack::MockRequest.env_for("/", *args) end it "pass valid request" do Rack::Lint.new(valid_app).call(env({})).first.must_equal 200 end it "notice fatal errors" do lambda { Rack::Lint.new(nil).call }.must_raise(Rack::Lint::LintError). message.must_match(/No env given/) end it "notice environment errors" do lambda { Rack::Lint.new(nil).call 5 }.must_raise(Rack::Lint::LintError). message.must_match(/not a Hash/) lambda { Rack::Lint.new(nil).call({}.freeze) }.must_raise(Rack::Lint::LintError). message.must_match(/env should not be frozen, but is/) lambda { e = env e.delete("REQUEST_METHOD") Rack::Lint.new(nil).call(e) }.must_raise(Rack::Lint::LintError). message.must_match(/missing required key REQUEST_METHOD/) lambda { e = env e.delete("SERVER_NAME") Rack::Lint.new(nil).call(e) }.must_raise(Rack::Lint::LintError). message.must_match(/missing required key SERVER_NAME/) lambda { e = env e.delete("SERVER_PROTOCOL") Rack::Lint.new(nil).call(e) }.must_raise(Rack::Lint::LintError). message.must_match(/missing required key SERVER_PROTOCOL/) lambda { e = env e["SERVER_PROTOCOL"] = 'Foo' Rack::Lint.new(nil).call(e) }.must_raise(Rack::Lint::LintError). message.must_match(/env\[SERVER_PROTOCOL\] does not match HTTP/) lambda { e = env e["HTTP_VERSION"] = 'HTTP/1.0' Rack::Lint.new(nil).call(e) }.must_raise(Rack::Lint::LintError). message.must_match(/env\[HTTP_VERSION\] does not equal env\[SERVER_PROTOCOL\]/) lambda { Rack::Lint.new(nil).call(env("HTTP_CONTENT_TYPE" => "text/plain")) }.must_raise(Rack::Lint::LintError). message.must_match(/contains HTTP_CONTENT_TYPE/) lambda { Rack::Lint.new(nil).call(env("HTTP_CONTENT_LENGTH" => "42")) }.must_raise(Rack::Lint::LintError). message.must_match(/contains HTTP_CONTENT_LENGTH/) lambda { Rack::Lint.new(nil).call(env("FOO" => Object.new)) }.must_raise(Rack::Lint::LintError). message.must_match(/non-string value/) lambda { Rack::Lint.new(nil).call(env("rack.url_scheme" => "gopher")) }.must_raise(Rack::Lint::LintError). message.must_match(/url_scheme unknown/) lambda { Rack::Lint.new(nil).call(env("rack.session" => [])) }.must_raise(Rack::Lint::LintError). message.must_equal "session [] must respond to store and []=" Rack::Lint.new(valid_app).call(env("rack.session" => {}))[0].must_equal 200 lambda { Rack::Lint.new(nil).call(env("rack.session" => {}.freeze)) }.must_raise(Rack::Lint::LintError). message.must_equal "session {} must respond to to_hash and return unfrozen Hash instance" obj = {} obj.singleton_class.send(:undef_method, :to_hash) lambda { Rack::Lint.new(nil).call(env("rack.session" => obj)) }.must_raise(Rack::Lint::LintError). message.must_equal "session {} must respond to to_hash and return unfrozen Hash instance" obj.singleton_class.send(:undef_method, :clear) lambda { Rack::Lint.new(nil).call(env("rack.session" => obj)) }.must_raise(Rack::Lint::LintError). message.must_equal "session {} must respond to clear" obj.singleton_class.send(:undef_method, :delete) lambda { Rack::Lint.new(nil).call(env("rack.session" => obj)) }.must_raise(Rack::Lint::LintError). message.must_equal "session {} must respond to delete" obj.singleton_class.send(:undef_method, :fetch) lambda { Rack::Lint.new(nil).call(env("rack.session" => obj)) }.must_raise(Rack::Lint::LintError). message.must_equal "session {} must respond to fetch and []" obj = Object.new def obj.inspect; '[]' end lambda { Rack::Lint.new(nil).call(env("rack.logger" => obj)) }.must_raise(Rack::Lint::LintError). message.must_equal "logger [] must respond to info" def obj.info(*) end lambda { Rack::Lint.new(nil).call(env("rack.logger" => obj)) }.must_raise(Rack::Lint::LintError). message.must_equal "logger [] must respond to debug" def obj.debug(*) end lambda { Rack::Lint.new(nil).call(env("rack.logger" => obj)) }.must_raise(Rack::Lint::LintError). message.must_equal "logger [] must respond to warn" def obj.warn(*) end lambda { Rack::Lint.new(nil).call(env("rack.logger" => obj)) }.must_raise(Rack::Lint::LintError). message.must_equal "logger [] must respond to error" def obj.error(*) end lambda { Rack::Lint.new(nil).call(env("rack.logger" => obj)) }.must_raise(Rack::Lint::LintError). message.must_equal "logger [] must respond to fatal" def obj.fatal(*) end Rack::Lint.new(valid_app).call(env("rack.logger" => obj))[0].must_equal 200 lambda { Rack::Lint.new(nil).call(env("rack.multipart.buffer_size" => 0)) }.must_raise(Rack::Lint::LintError). message.must_equal "rack.multipart.buffer_size must be an Integer > 0 if specified" Rack::Lint.new(valid_app).call(env("rack.multipart.buffer_size" => 1))[0].must_equal 200 lambda { Rack::Lint.new(nil).call(env("rack.multipart.tempfile_factory" => Tempfile)) }.must_raise(Rack::Lint::LintError). message.must_equal "rack.multipart.tempfile_factory must respond to #call" lambda { Rack::Lint.new(lambda { |env| env['rack.multipart.tempfile_factory'].call("testfile", "text/plain") }).call(env("rack.multipart.tempfile_factory" => lambda { |filename, content_type| Object.new })) }.must_raise(Rack::Lint::LintError). message.must_equal "rack.multipart.tempfile_factory return value must respond to #<<" lambda { Rack::Lint.new(lambda { |env| env['rack.multipart.tempfile_factory'].call("testfile", "text/plain") [] }).call(env("rack.multipart.tempfile_factory" => lambda { |filename, content_type| String.new })) }.must_raise(Rack::Lint::LintError). message.must_equal "response array has 0 elements instead of 3" lambda { Rack::Lint.new(nil).call(env("SERVER_PORT" => "howdy")) }.must_raise(Rack::Lint::LintError). message.must_equal 'env[SERVER_PORT] is not an Integer' lambda { Rack::Lint.new(nil).call(env("SERVER_NAME" => "\u1234")) }.must_raise(Rack::Lint::LintError). message.must_equal "\u1234 must be a valid authority" lambda { Rack::Lint.new(nil).call(env("HTTP_HOST" => "\u1234")) }.must_raise(Rack::Lint::LintError). message.must_equal "\u1234 must be a valid authority" lambda { Rack::Lint.new(nil).call(env("REQUEST_METHOD" => "FUCKUP?")) }.must_raise(Rack::Lint::LintError). message.must_match(/REQUEST_METHOD/) lambda { Rack::Lint.new(nil).call(env("REQUEST_METHOD" => "OOPS?\b!")) }.must_raise(Rack::Lint::LintError). message.must_match(/OOPS\?\\/) lambda { Rack::Lint.new(nil).call(env("SCRIPT_NAME" => "howdy")) }.must_raise(Rack::Lint::LintError). message.must_match(/must start with/) lambda { Rack::Lint.new(nil).call(env("PATH_INFO" => "../foo")) }.must_raise(Rack::Lint::LintError). message.must_match(/must start with/) lambda { Rack::Lint.new(nil).call(env("CONTENT_LENGTH" => "xcii")) }.must_raise(Rack::Lint::LintError). message.must_match(/Invalid CONTENT_LENGTH/) lambda { Rack::Lint.new(nil).call(env("QUERY_STRING" => nil)) }.must_raise(Rack::Lint::LintError). message.must_include('env variable QUERY_STRING has non-string value nil') lambda { Rack::Lint.new(nil).call(env("QUERY_STRING" => "\u1234")) }.must_raise(Rack::Lint::LintError). message.must_include('env variable QUERY_STRING has value containing non-ASCII characters and has non-ASCII-8BIT encoding') Rack::Lint.new(lambda { |env| [200, {}, []] }).call(env("QUERY_STRING" => "\u1234".b)).first.must_equal 200 lambda { e = env e.delete("PATH_INFO") e.delete("SCRIPT_NAME") Rack::Lint.new(nil).call(e) }.must_raise(Rack::Lint::LintError). message.must_match(/One of .* must be set/) lambda { Rack::Lint.new(nil).call(env("SCRIPT_NAME" => "/")) }.must_raise(Rack::Lint::LintError). message.must_match(/cannot be .* make it ''/) end it "notice input errors" do lambda { Rack::Lint.new(nil).call(env("rack.input" => "")) }.must_raise(Rack::Lint::LintError). message.must_match(/does not respond to #gets/) lambda { input = Object.new def input.binmode? false end Rack::Lint.new(nil).call(env("rack.input" => input)) }.must_raise(Rack::Lint::LintError). message.must_match(/is not opened in binary mode/) lambda { input = Object.new def input.external_encoding result = Object.new def result.name "US-ASCII" end result end Rack::Lint.new(nil).call(env("rack.input" => input)) }.must_raise(Rack::Lint::LintError). message.must_match(/does not have ASCII-8BIT as its external encoding/) end it "notice error errors" do lambda { io = StringIO.new io.binmode Rack::Lint.new(nil).call(env("rack.errors" => "", "rack.input" => io)) }.must_raise(Rack::Lint::LintError). message.must_match(/does not respond to #puts/) end it "notice response errors" do lambda { Rack::Lint.new(lambda { |env| "" }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_include('response is not an Array, but String') lambda { Rack::Lint.new(lambda { |env| [nil, nil, nil, nil] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_include('response array has 4 elements instead of 3') end it "notice status errors" do lambda { Rack::Lint.new(lambda { |env| ["cc", {}, ""] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/must be an Integer >=100/) lambda { Rack::Lint.new(lambda { |env| [42, {}, ""] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/must be an Integer >=100/) lambda { Rack::Lint.new(lambda { |env| ["200", {}, ""] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/must be an Integer >=100/) end it "notice header errors" do obj = Object.new def obj.each; end lambda { io = StringIO.new('a') io.binmode Rack::Lint.new(lambda { |env| env['rack.input'].each{ |x| } [200, obj, []] }).call(env({ "rack.input" => io })) }.must_raise(Rack::Lint::LintError). message.must_equal "headers object should be a hash, but isn't (got Object as headers)" lambda { Rack::Lint.new(lambda { |env| [200, {}.freeze, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_equal "headers object should not be frozen, but is" lambda { Rack::Lint.new(lambda { |env| [200, { true => false }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_equal "header key must be a string, was TrueClass" lambda { Rack::Lint.new(lambda { |env| [200, { "status" => "404" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/must not contain status/) # From RFC 7230: # Most HTTP header field values are defined using common syntax # components (token, quoted-string, and comment) separated by # whitespace or specific delimiting characters. Delimiters are chosen # from the set of US-ASCII visual characters not allowed in a token # (DQUOTE and "(),/:;<=>?@[\]{}"). Rack also doesn't allow uppercase # ASCII (A-Z) in header keys. # # token = 1*tchar # # tchar = "!" / "#" / "$" / "%" / "&" / "'" / "*" # / "+" / "-" / "." / "^" / "_" / "`" / "|" / "~" # / DIGIT / ALPHA # ; any VCHAR, except delimiters invalid_headers = 0.upto(31).map(&:chr) + %W<( ) , / : ; < = > ? @ [ \\ ] { } \x7F> invalid_headers.each do |invalid_header| lambda { Rack::Lint.new(lambda { |env| [200, { invalid_header => "text/plain" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError, "on invalid header: #{invalid_header}"). message.must_equal("invalid header name: #{invalid_header}") end ('A'..'Z').each do |invalid_header| lambda { Rack::Lint.new(lambda { |env| [200, { invalid_header => "text/plain" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError, "on invalid header: #{invalid_header}"). message.must_equal("uppercase character in header name: #{invalid_header}") end valid_headers = 0.upto(127).map(&:chr) - invalid_headers - ('A'..'Z').to_a valid_headers.each do |valid_header| Rack::Lint.new(lambda { |env| [200, { valid_header => "text/plain" }, []] }).call(env({})).first.must_equal 200 end lambda { Rack::Lint.new(lambda { |env| [200, { "foo" => Object.new }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_equal "a header value must be a String or Array of Strings, but the value of 'foo' is a Object" lambda { Rack::Lint.new(lambda { |env| [200, { "foo-bar" => "text\000plain" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/invalid header/) lambda { Rack::Lint.new(lambda { |env| [200, [%w(content-type text/plain), %w(content-length 0)], []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_equal "headers object should be a hash, but isn't (got Array as headers)" end it "notice content-type errors" do # lambda { # Rack::Lint.new(lambda { |env| # [200, {"content-length" => "0"}, []] # }).call(env({})) # }.must_raise(Rack::Lint::LintError). # message.must_match(/No content-type/) [100, 101, 204, 304].each do |status| lambda { Rack::Lint.new(lambda { |env| [status, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/content-type header found/) end end it "notice content-length errors" do [100, 101, 204, 304].each do |status| lambda { Rack::Lint.new(lambda { |env| [status, { "content-length" => "0" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/content-length header found/) end lambda { Rack::Lint.new(lambda { |env| [200, { "content-type" => "text/plain", "content-length" => "1" }, []] }).call(env({}))[2].each { } }.must_raise(Rack::Lint::LintError). message.must_match(/content-length header was 1, but should be 0/) end it "notice body errors" do lambda { body = Rack::Lint.new(lambda { |env| [200, { "content-type" => "text/plain", "content-length" => "3" }, [1, 2, 3]] }).call(env({}))[2] body.each { |part| } }.must_raise(Rack::Lint::LintError). message.must_match(/yielded non-string/) lambda { body = Rack::Lint.new(lambda { |env| [200, { "content-type" => "text/plain", "content-length" => "3" }, Object.new] }).call(env({}))[2] body.respond_to?(:to_ary).must_equal false body.each { |part| } }.must_raise(Rack::Lint::LintError). message.must_equal 'Enumerable Body must respond to each' lambda { body = Rack::Lint.new(lambda { |env| [200, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env({}))[2] body.each { |part| } body.each { |part| } }.must_raise(Rack::Lint::LintError). message.must_equal 'Response body must only be invoked once (each)' # Lint before and after the Rack middleware being tested. def stacked_lint(app) Rack::Lint.new(lambda do |env| Rack::Lint.new(app).call(env).tap {|response| response[2] = yield response[2]} end) end yielder_app = lambda do |_| input = Object.new def input.each; 10.times {yield 'foo'}; end [200, {"content-type" => "text/plain", "content-length" => "30"}, input] end lambda { body = stacked_lint(yielder_app) {|body| new_body = Struct.new(:body) do def each(&block) body.each { |part| yield part.upcase } body.close end end new_body.new(body) }.call(env({}))[2] body.each {|part| part.must_equal 'FOO'} body.close }.call lambda { body = stacked_lint(yielder_app) { |body| body.enum_for.to_a }.call(env({}))[2] body.each {} body.close }.must_raise(Rack::Lint::LintError). message.must_match(/Middleware must not call #each directly/) lambda { body = stacked_lint(yielder_app) { |body| new_body = Struct.new(:body) do def each(&block) body.enum_for.each_slice(2) { |parts| yield parts.join } end end new_body.new(body) }.call(env({}))[2] body.each {} body.close }.must_raise(Rack::Lint::LintError). message.must_match(/New body must yield at least once per iteration of old body/) lambda { body = stacked_lint(yielder_app) { |body| Struct.new(:body) do def each; body.each {|part| yield part} end end.new(body) }.call(env({}))[2] body.each {} body.close }.must_raise(Rack::Lint::LintError). message.must_match(/Body has not been closed/) static_app = lambda do |_| input = ['foo'] * 10 [200, {"content-type" => "text/plain", "content-length" => "30"}, input] end lambda { body = stacked_lint(static_app) { |body| body.to_ary}.call(env({}))[2] body.each {} body.close }.call array_mismatch = lambda do |_| input = Object.new def input.to_ary; ['bar'] * 10; end def input.each; 10.times {yield 'foo'}; end [200, {"content-type" => "text/plain", "content-length" => "30"}, input] end lambda { body = stacked_lint(array_mismatch) { |body| body.to_ary}.call(env({}))[2] body.each {} body.close }.must_raise(Rack::Lint::LintError). message.must_match(/#to_ary not identical to contents produced by calling #each/) lambda { body = Rack::Lint.new(lambda { |env| to_path = Object.new def to_path.each; end def to_path.to_path; 'non-existent' end [200, { "content-type" => "text/plain", "content-length" => "0" }, to_path] }).call(env({}))[2] body.each { |part| } }.must_raise(Rack::Lint::LintError). message.must_equal 'The file identified by body.to_path does not exist' lambda { body = Rack::Lint.new(lambda { |env| [200, { "content-type" => "text/plain", "content-length" => "0" }, Object.new] }).call(env({}))[2] body.call(nil) }.must_raise(Rack::Lint::LintError). message.must_equal 'Streaming Body must respond to call' lambda { body = Rack::Lint.new(lambda { |env| [200, { "content-type" => "text/plain", "content-length" => "0" }, proc{}] }).call(env({}))[2] body.call(StringIO.new) body.call(nil) }.must_raise(Rack::Lint::LintError). message.must_equal 'Response body must only be invoked once (call)' lambda { body = Rack::Lint.new(lambda { |env| [200, { "content-type" => "text/plain", "content-length" => "0" }, proc{}] }).call(env({}))[2] body.call(nil) }.must_raise(Rack::Lint::LintError). message.must_equal 'Stream must respond to read' end it "notice input handling errors" do lambda { Rack::Lint.new(lambda { |env| env["rack.input"].gets("\r\n") [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/gets called with arguments/) lambda { Rack::Lint.new(lambda { |env| env["rack.input"].gets env["rack.input"].read(1, 2, 3) [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/read called with too many arguments/) lambda { Rack::Lint.new(lambda { |env| env["rack.input"].read("foo") [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/read called with non-integer and non-nil length/) lambda { Rack::Lint.new(lambda { |env| env["rack.input"].read(-1) [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/read called with a negative length/) lambda { Rack::Lint.new(lambda { |env| env["rack.input"].read(nil, nil) [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/read called with non-String buffer/) lambda { Rack::Lint.new(lambda { |env| env["rack.input"].read(nil, 1) [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/read called with non-String buffer/) weirdio = Object.new class << weirdio def gets 42 end def read 23 end def each yield 23 yield 42 end end eof_weirdio = Object.new class << eof_weirdio def gets nil end def read(*args) nil end def each end end lambda { Rack::Lint.new(lambda { |env| env["rack.input"].gets [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env("rack.input" => weirdio)) }.must_raise(Rack::Lint::LintError). message.must_match(/gets didn't return a String/) lambda { Rack::Lint.new(lambda { |env| env["rack.input"].each(1) { |x| } [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env("rack.input" => weirdio)) }.must_raise(Rack::Lint::LintError). message.must_match(/rack.input#each called with arguments/) lambda { Rack::Lint.new(lambda { |env| env["rack.input"].each { |x| } [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env("rack.input" => weirdio)) }.must_raise(Rack::Lint::LintError). message.must_match(/each didn't yield a String/) lambda { Rack::Lint.new(lambda { |env| env["rack.input"].read [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env("rack.input" => weirdio)) }.must_raise(Rack::Lint::LintError). message.must_match(/read didn't return nil or a String/) lambda { Rack::Lint.new(lambda { |env| env["rack.input"].read [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env("rack.input" => eof_weirdio)) }.must_raise(Rack::Lint::LintError). message.must_match(/read\(nil\) returned nil on EOF/) lambda { Rack::Lint.new(lambda { |env| env["rack.input"].close [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/close must not be called/) end it "notice error handling errors" do lambda { Rack::Lint.new(lambda { |env| env["rack.errors"].write(42) [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/write not called with a String/) lambda { Rack::Lint.new(lambda { |env| env["rack.errors"].close [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env({})) }.must_raise(Rack::Lint::LintError). message.must_match(/close must not be called/) end it "notice HEAD errors" do Rack::Lint.new(lambda { |env| [200, { "content-type" => "test/plain", "content-length" => "3" }, []] }).call(env({ "REQUEST_METHOD" => "HEAD" })).first.must_equal 200 lambda { Rack::Lint.new(lambda { |env| [200, { "content-type" => "test/plain", "content-length" => "3" }, ["foo"]] }).call(env({ "REQUEST_METHOD" => "HEAD" }))[2].each { } }.must_raise(Rack::Lint::LintError). message.must_match(/body was given for HEAD/) end def assert_lint(*args) hello_str = "hello world".dup hello_str.force_encoding(Encoding::ASCII_8BIT) Rack::Lint.new(lambda { |env| env["rack.input"].send(:read, *args) [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env({ "rack.input" => StringIO.new(hello_str) })). first.must_equal 201 end it "pass valid read calls" do assert_lint assert_lint 0 assert_lint 1 assert_lint nil assert_lint nil, ''.dup assert_lint 1, ''.dup end it "notices when request env doesn't have a valid rack.hijack callback" do lambda { Rack::Lint.new(lambda { |env| env['rack.hijack'].call [201, { "content-type" => "text/plain", "content-length" => "0" }, []] }).call(env({ 'rack.hijack' => Object.new })) }.must_raise(Rack::Lint::LintError). message.must_match(/rack.hijack must respond to call/) end it "notices when the response headers don't have a valid rack.hijack callback" do lambda { Rack::Lint.new(lambda { |env| [201, { "content-type" => "text/plain", "content-length" => "0", 'rack.hijack' => Object.new }, []] }).call(env({ 'rack.hijack?' => true })) }.must_raise(Rack::Lint::LintError). message.must_equal 'rack.hijack header must respond to #call' end end