lint.rb consistency improvements as suggested by Claude.

Author: samuel-williams-shopify

SPEC.rdoc

@@ -34,7 +34,7 @@ The remainder of the request URL's "path", designating the virtual "location" of
 
 The <tt>PATH_INFO</tt>, if provided, must be a valid request target or an empty string, as defined by {RFC9110}[https://datatracker.ietf.org/doc/html/rfc9110#target.resource].
 * Only <tt>OPTIONS</tt> requests may have <tt>PATH_INFO</tt> set to <tt>*</tt> (asterisk-form).
-* Only <tt>CONNECT</tt> requests may have <tt>PATH_INFO</tt> set to an authority (authority-form). Note that in HTTP/2+, the authority-form is not a valid request target.
+* Only <tt>CONNECT</tt> requests may have <tt>PATH_INFO</tt> set to an authority (authority-form). Note that in <tt>HTTP/2+</tt>, the authority-form is not a valid request target.
 * <tt>CONNECT</tt> and <tt>OPTIONS</tt> requests must not have <tt>PATH_INFO</tt> set to a URI (absolute-form).
 * Otherwise, <tt>PATH_INFO</tt> must start with a <tt>/</tt> and must not include a fragment part starting with <tt>#</tt> (origin-form).
 
@@ -88,7 +88,7 @@ The URL scheme, which must be one of <tt>http</tt>, <tt>https</tt>, <tt>ws</tt>
 
 ==== <tt>rack.protocol</tt>
 
-An optional +Array+ of +String+ values, containing the protocols advertised by the client in the <tt>upgrade</tt> header (HTTP/1) or the <tt>:protocol</tt> pseudo-header (HTTP/2+).
+An optional +Array+ of +String+ values, containing the protocols advertised by the client in the <tt>upgrade</tt> header (<tt>HTTP/1</tt>) or the <tt>:protocol</tt> pseudo-header (<tt>HTTP/2+</tt>).
 
 ==== <tt>rack.session</tt>
 
@@ -167,13 +167,13 @@ The error stream must respond to +puts+, +write+ and +flush+:
 
 The hijacking interfaces provides a means for an application to take control of the HTTP connection. There are two distinct hijack interfaces: full hijacking where the application takes over the raw connection, and partial hijacking where the application takes over just the response body stream. In both cases, the application is responsible for closing the hijacked stream.
 
-Full hijacking only works with HTTP/1. Partial hijacking is functionally equivalent to streaming bodies, and is still optionally supported for backwards compatibility with older Rack versions.
+Full hijacking only works with <tt>HTTP/1</tt>. Partial hijacking is functionally equivalent to streaming bodies, and is still optionally supported for backwards compatibility with older Rack versions.
 
 ==== Full Hijack
 
-Full hijack is used to completely take over an HTTP/1 connection. It occurs before any headers are written and causes the server to ignore any response generated by the application. It is intended to be used when applications need access to the raw HTTP/1 connection.
+Full hijack is used to completely take over an <tt>HTTP/1</tt> connection. It occurs before any headers are written and causes the server to ignore any response generated by the application. It is intended to be used when applications need access to the raw <tt>HTTP/1</tt> connection.
 
-If <tt>rack.hijack</tt> is present in +env+, it must respond to +call+ and return an +IO+ instance which can be used to read and write to the underlying connection using HTTP/1 semantics and formatting.
+If <tt>rack.hijack</tt> is present in +env+, it must respond to +call+ and return an +IO+ instance which can be used to read and write to the underlying connection using <tt>HTTP/1</tt> semantics and formatting.
 
 ==== Partial Hijack
 
@@ -205,23 +205,23 @@ This is an HTTP status. It must be an Integer greater than or equal to 100.
 The headers must be a unfrozen +Hash+. The header keys must be +String+ objects. Special headers starting <tt>rack.</tt> are for communicating with the server, and must not be sent back to the client.
 
 * The headers must not contain a <tt>"status"</tt> key.
-* Header keys must conform to RFC7230 token specification, i.e. cannot contain non-printable ASCII, DQUOTE or <tt>(),/:;<=>?@[\]{}</tt>.
+* Header keys must conform to {RFC7230}[https://tools.ietf.org/html/rfc7230] token specification, i.e. cannot contain non-printable ASCII, DQUOTE or <tt>(),/:;<=>?@[\]{}</tt>.
 * Header keys must not contain uppercase ASCII characters (A-Z).
 * Header values must be either a +String+ value, or an +Array+ of +String+ values, such that each +String+ value must not contain characters with an ASCII ordinal below 040 (32).
 
 ==== The <tt>content-type</tt> Header
 
-There must not be a <tt>content-type</tt> header key when the status is 1xx, 204, or 304.
+There must not be a <tt>content-type</tt> header key when the status is <tt>1xx</tt>, <tt>204</tt>, or <tt>304</tt>.
 
 ==== The <tt>content-length</tt> Header
 
-There must not be a <tt>content-length</tt> header key when the status is 1xx, 204, or 304.
+There must not be a <tt>content-length</tt> header key when the status is <tt>1xx</tt>, <tt>204</tt>, or <tt>304</tt>.
 
 ==== The <tt>rack.protocol</tt> Header
 
 If the <tt>rack.protocol</tt> header is present, it must be a +String+, and must be one of the values from the <tt>rack.protocol</tt> array from the environment.
 
-Setting this value informs the server that it should perform a connection upgrade. In HTTP/1, this is done using the +upgrade+ header. In HTTP/2, this is done by accepting the request.
+Setting this value informs the server that it should perform a connection upgrade. In <tt>HTTP/1</tt>, this is done using the +upgrade+ header. In <tt>HTTP/2</tt>, this is done by accepting the request.
 
 === The Body
 
@@ -249,7 +249,7 @@ If the Body responds to +to_ary+, it must return an +Array+ whose contents are i
 
 The Streaming Body must respond to +call+. It must only be called once. It must not be called after being closed. It takes a +stream+ argument.
 
-The +stream+ argument must respond to: +read+, +write+, <tt><<</tt>, +flush+, +close+, +close_read+, +close_write+, and +closed?+. The semantics of these +IO+ methods must be a best effort match to those of a normal Ruby +IO+ or +Socket+ object, using standard arguments and raising standard exceptions. Servers may simply pass on real +IO+ objects to the Streaming Body. In some cases (e.g. when using <tt>transfer-encoding</tt> or HTTP/2+), the server may need to provide a wrapper that implements the required methods, in order to provide the correct semantics.
+The +stream+ argument must respond to: +read+, +write+, <tt><<</tt>, +flush+, +close+, +close_read+, +close_write+, and +closed?+. The semantics of these +IO+ methods must be a best effort match to those of a normal Ruby +IO+ or +Socket+ object, using standard arguments and raising standard exceptions. Servers may simply pass on real +IO+ objects to the Streaming Body. In some cases (e.g. when using <tt>transfer-encoding</tt> or <tt>HTTP/2+</tt>), the server may need to provide a wrapper that implements the required methods, in order to provide the correct semantics.
 
 == Thanks
 

lib/rack/lint.rb

@@ -10,12 +10,12 @@ module Rack
   class Lint
     # Represents a failure to meet the Rack specification.
     class LintError < RuntimeError; end
-    
+
     # Invoke the application, validating the request and response according to the Rack spec.
     def call(env = nil)
       Wrapper.new(@app, env).response
     end
-    
+
     # :stopdoc:
 
     ALLOWED_SCHEMES = %w(https http wss ws).freeze
@@ -55,6 +55,10 @@ def call(env = nil)
 
     # N.B. The empty `##` comments creates paragraphs in the output. A trailing "\" is used to escape the newline character, which combines the comments into a single paragraph.
     #
+    # Formatting conventions for documentation:
+    # - Use <tt> for: literal values, constants, method signatures, environment keys
+    # - Use + for: Ruby types, concepts, method names, class references
+    #
     ## = Rack Specification
     ##
     ## This specification aims to formalize the Rack protocol. You can (and should) use +Rack::Lint+ to enforce it. When you develop middleware, be sure to test with +Rack::Lint+ to catch possible violations of this specification.
@@ -213,7 +217,7 @@ def check_environment(env)
               raise LintError, "Only OPTIONS requests may have PATH_INFO set to '*' (asterisk-form)"
             end
           when REQUEST_PATH_AUTHORITY_FORM
-            ## * Only <tt>CONNECT</tt> requests may have <tt>PATH_INFO</tt> set to an authority (authority-form). Note that in HTTP/2+, the authority-form is not a valid request target.
+            ## * Only <tt>CONNECT</tt> requests may have <tt>PATH_INFO</tt> set to an authority (authority-form). Note that in <tt>HTTP/2+</tt>, the authority-form is not a valid request target.
             unless env[REQUEST_METHOD] == CONNECT
               raise LintError, "Only CONNECT requests may have PATH_INFO set to an authority (authority-form)"
             end
@@ -325,7 +329,7 @@ def check_environment(env)
         ##
         ## ==== <tt>rack.protocol</tt>
         ##
-        ## An optional +Array+ of +String+ values, containing the protocols advertised by the client in the <tt>upgrade</tt> header (HTTP/1) or the <tt>:protocol</tt> pseudo-header (HTTP/2+).
+        ## An optional +Array+ of +String+ values, containing the protocols advertised by the client in the <tt>upgrade</tt> header (<tt>HTTP/1</tt>) or the <tt>:protocol</tt> pseudo-header (<tt>HTTP/2+</tt>).
         if protocols = env[RACK_PROTOCOL]
           unless protocols.is_a?(Array) && protocols.all?{|protocol| protocol.is_a?(String)}
             raise LintError, "rack.protocol must be an Array of Strings"
@@ -610,11 +614,11 @@ def close(*args)
       ##
       ## The hijacking interfaces provides a means for an application to take control of the HTTP connection. There are two distinct hijack interfaces: full hijacking where the application takes over the raw connection, and partial hijacking where the application takes over just the response body stream. In both cases, the application is responsible for closing the hijacked stream.
       ##
-      ## Full hijacking only works with HTTP/1. Partial hijacking is functionally equivalent to streaming bodies, and is still optionally supported for backwards compatibility with older Rack versions.
+      ## Full hijacking only works with <tt>HTTP/1</tt>. Partial hijacking is functionally equivalent to streaming bodies, and is still optionally supported for backwards compatibility with older Rack versions.
       ##
       ## ==== Full Hijack
       ##
-      ## Full hijack is used to completely take over an HTTP/1 connection. It occurs before any headers are written and causes the server to ignore any response generated by the application. It is intended to be used when applications need access to the raw HTTP/1 connection.
+      ## Full hijack is used to completely take over an <tt>HTTP/1</tt> connection. It occurs before any headers are written and causes the server to ignore any response generated by the application. It is intended to be used when applications need access to the raw <tt>HTTP/1</tt> connection.
       ##
       def check_hijack(env)
         ## If <tt>rack.hijack</tt> is present in +env+, it must respond to +call+ \
@@ -624,7 +628,7 @@ def check_hijack(env)
           env[RACK_HIJACK] = proc do
             io = original_hijack.call
 
-            ## and return an +IO+ instance which can be used to read and write to the underlying connection using HTTP/1 semantics and formatting.
+            ## and return an +IO+ instance which can be used to read and write to the underlying connection using <tt>HTTP/1</tt> semantics and formatting.
             raise LintError, "rack.hijack must return an IO instance" unless io.is_a?(IO)
 
             io
@@ -724,7 +728,7 @@ def check_headers(headers)
           ##
           ## * The headers must not contain a <tt>"status"</tt> key.
           raise LintError, "headers must not contain status" if key == "status"
-          ## * Header keys must conform to RFC7230 token specification, i.e. cannot contain non-printable ASCII, DQUOTE or <tt>(),/:;<=>?@[\]{}</tt>.
+          ## * Header keys must conform to {RFC7230}[https://tools.ietf.org/html/rfc7230] token specification, i.e. cannot contain non-printable ASCII, DQUOTE or <tt>(),/:;<=>?@[\]{}</tt>.
           raise LintError, "invalid header name: #{key}" if key =~ /[\(\),\/:;<=>\?@\[\\\]{}[:cntrl:]]/
           ## * Header keys must not contain uppercase ASCII characters (A-Z).
           raise LintError, "uppercase character in header name: #{key}" if key =~ /[A-Z]/
@@ -753,7 +757,7 @@ def check_header_value(key, value)
       ##
       def check_content_type_header(status, headers)
         headers.each do |key, value|
-          ## There must not be a <tt>content-type</tt> header key when the status is 1xx, 204, or 304.
+          ## There must not be a <tt>content-type</tt> header key when the status is <tt>1xx</tt>, <tt>204</tt>, or <tt>304</tt>.
           if key == "content-type"
             if Rack::Utils::STATUS_WITH_NO_ENTITY_BODY.key? status.to_i
               raise LintError, "content-type header found in #{status} response, not allowed"
@@ -769,7 +773,7 @@ def check_content_type_header(status, headers)
       def check_content_length_header(status, headers)
         headers.each do |key, value|
           if key == 'content-length'
-            ## There must not be a <tt>content-length</tt> header key when the status is 1xx, 204, or 304.
+            ## There must not be a <tt>content-length</tt> header key when the status is <tt>1xx</tt>, <tt>204</tt>, or <tt>304</tt>.
             if Rack::Utils::STATUS_WITH_NO_ENTITY_BODY.key? status.to_i
               raise LintError, "content-length header found in #{status} response, not allowed"
             end
@@ -808,7 +812,7 @@ def check_rack_protocol_header(status, headers)
         end
       end
       ##
-      ## Setting this value informs the server that it should perform a connection upgrade. In HTTP/1, this is done using the +upgrade+ header. In HTTP/2, this is done by accepting the request.
+      ## Setting this value informs the server that it should perform a connection upgrade. In <tt>HTTP/1</tt>, this is done using the +upgrade+ header. In <tt>HTTP/2</tt>, this is done by accepting the request.
       ##
       ## === The Body
       ##
@@ -937,7 +941,7 @@ def call(stream)
       class StreamWrapper
         extend Forwardable
 
-        ## The semantics of these +IO+ methods must be a best effort match to those of a normal Ruby +IO+ or +Socket+ object, using standard arguments and raising standard exceptions. Servers may simply pass on real +IO+ objects to the Streaming Body. In some cases (e.g. when using <tt>transfer-encoding</tt> or HTTP/2+), the server may need to provide a wrapper that implements the required methods, in order to provide the correct semantics.
+        ## The semantics of these +IO+ methods must be a best effort match to those of a normal Ruby +IO+ or +Socket+ object, using standard arguments and raising standard exceptions. Servers may simply pass on real +IO+ objects to the Streaming Body. In some cases (e.g. when using <tt>transfer-encoding</tt> or <tt>HTTP/2+</tt>), the server may need to provide a wrapper that implements the required methods, in order to provide the correct semantics.
         REQUIRED_METHODS = [
           :read, :write, :<<, :flush, :close,
           :close_read, :close_write, :closed?