Preserve header casing as specified

lib/http/headers.rb

@@ -21,6 +21,10 @@ class Headers
 
     # Class constructor.
     def initialize
+      # The @pile stores each header value using a three element array:
+      #  0 - the normalized header key, used for lookup
+      #  1 - the header key as it will be sent with a request
+      #  2 - the value
       @pile = []
     end
 
@@ -45,20 +49,39 @@ def delete(name)
 
     # Appends header.
     #
-    # @param [#to_s] name header name
+    # @param [String, Symbol] name header name. When specified as a string, the
+    #   name is sent as-is. When specified as a symbol, the name is converted
+    #   to a string of capitalized words separated by a dash. Word boundaries
+    #   are determined by an underscore (`_`) or a dash (`-`).
+    #   Ex: `:content_type` is sent as `"Content-Type"`, and `"auth_key"` (string)
+    #   is sent as `"auth_key"`.
     # @param [Array<#to_s>, #to_s] value header value(s) to be appended
     # @return [void]
     def add(name, value)
-      name = normalize_header name.to_s
-      Array(value).each { |v| @pile << [name, validate_value(v)] }
+      lookup_name = normalize_header(name.to_s)
+      wire_name = case name
+                  when String
+                    name
+                  when Symbol
+                    lookup_name
+                  else
+                    raise HTTP::HeaderError, "HTTP header must be a String or Symbol: #{name.inspect}"
+                  end
+      Array(value).each do |v|
+        @pile << [
+          lookup_name,
+          wire_name,
+          validate_value(v)
+        ]
+      end
     end
 
     # Returns list of header values if any.
     #
     # @return [Array<String>]
     def get(name)
       name = normalize_header name.to_s
-      @pile.select { |k, _| k == name }.map { |_, v| v }
+      @pile.select { |k, _| k == name }.map { |_, _, v| v }
     end
 
     # Smart version of {#get}.
@@ -96,7 +119,7 @@ def to_h
     #
     # @return [Array<[String, String]>]
     def to_a
-      @pile.map { |pair| pair.map(&:dup) }
+      @pile.map { |item| item[1..2] }
     end
 
     # Returns human-readable representation of `self` instance.
@@ -110,7 +133,7 @@ def inspect
     #
     # @return [Array<String>]
     def keys
-      @pile.map { |k, _| k }.uniq
+      @pile.map { |_, k, _| k }.uniq
     end
 
     # Compares headers to another Headers or Array of key/value pairs
@@ -119,7 +142,7 @@ def keys
     def ==(other)
       return false unless other.respond_to? :to_a
 
-      @pile == other.to_a
+      to_a == other.to_a
     end
 
     # Calls the given block once for each key/value pair in headers container.
@@ -129,7 +152,7 @@ def ==(other)
     def each
       return to_enum(__method__) unless block_given?
 
-      @pile.each { |arr| yield(arr) }
+      @pile.each { |item| yield(item[1..2]) }
       self
     end
 
@@ -152,7 +175,7 @@ def each
     # @api private
     def initialize_copy(orig)
       super
-      @pile = to_a
+      @pile = @pile.map(&:dup)
     end
 
     # Merges `other` headers into `self`.

spec/lib/http/connection_spec.rb

@@ -20,14 +20,17 @@
         <<-RESPONSE.gsub(/^\s*\| */, "").gsub(/\n/, "\r\n")
         | HTTP/1.1 200 OK
         | Content-Type: text
+        | foo_bar: 123
         |
         RESPONSE
       end
     end
 
-    it "reads data in parts" do
+    it "populates headers collection, preserving casing" do
       connection.read_headers!
-      expect(connection.headers).to eq("Content-Type" => "text")
+      expect(connection.headers).to eq("Content-Type" => "text", "foo_bar" => "123")
+      expect(connection.headers["Foo-Bar"]).to eq("123")
+      expect(connection.headers["foo_bar"]).to eq("123")
     end
   end
 

spec/lib/http/headers_spec.rb

@@ -13,7 +13,7 @@
       expect(headers["Accept"]).to eq "application/json"
     end
 
-    it "normalizes header name" do
+    it "allows retrieval via normalized header name" do
       headers.set :content_type, "application/json"
       expect(headers["Content-Type"]).to eq "application/json"
     end
@@ -54,7 +54,7 @@
       expect(headers["Accept"]).to eq "application/json"
     end
 
-    it "normalizes header name" do
+    it "allows retrieval via normalized header name" do
       headers[:content_type] = "application/json"
       expect(headers["Content-Type"]).to eq "application/json"
     end
@@ -80,7 +80,7 @@
       expect(headers["Content-Type"]).to be_nil
     end
 
-    it "normalizes header name" do
+    it "removes header that matches normalized version of specified name" do
       headers.delete :content_type
       expect(headers["Content-Type"]).to be_nil
     end
@@ -104,13 +104,13 @@
       expect(headers["Accept"]).to eq "application/json"
     end
 
-    it "normalizes header name" do
+    it "allows retrieval via normalized header name" do
       headers.add :content_type, "application/json"
       expect(headers["Content-Type"]).to eq "application/json"
     end
 
     it "appends new value if header exists" do
-      headers.add :set_cookie, "hoo=ray"
+      headers.add "Set-Cookie", "hoo=ray"
       headers.add :set_cookie, "woo=hoo"
       expect(headers["Set-Cookie"]).to eq %w[hoo=ray woo=hoo]
     end
@@ -137,6 +137,11 @@
       expect { headers.add "foo", "bar\nEvil-Header: evil-value" }.
         to raise_error HTTP::HeaderError
     end
+
+    it "fails when header name is not a String or Symbol" do
+      expect { headers.add 2, "foo" }.
+        to raise_error HTTP::HeaderError
+    end
   end
 
   describe "#get" do
@@ -314,6 +319,17 @@
       )
     end
 
+    it "yields header keys specified as symbols in normalized form" do
+      keys = headers.each.map(&:first)
+      expect(keys).to eq(["Set-Cookie", "Content-Type", "Set-Cookie"])
+    end
+
+    it "yields headers specified as strings without conversion" do
+      headers.add "X_kEy", "value"
+      keys = headers.each.map(&:first)
+      expect(keys).to eq(["Set-Cookie", "Content-Type", "Set-Cookie", "X_kEy"])
+    end
+
     it "returns self instance if block given" do
       expect(headers.each { |*| }).to be headers
     end
@@ -490,14 +506,15 @@
     end
 
     context "with duplicate header keys (mixed case)" do
-      let(:headers) { {"Set-Cookie" => "hoo=ray", "set-cookie" => "woo=hoo"} }
+      let(:headers) { {"Set-Cookie" => "hoo=ray", "set_cookie" => "woo=hoo", :set_cookie => "ta=da"} }
 
       it "adds all headers" do
         expect(described_class.coerce(headers).to_a).
           to match_array(
             [
               %w[Set-Cookie hoo=ray],
-              %w[Set-Cookie woo=hoo]
+              %w[set_cookie woo=hoo],
+              %w[Set-Cookie ta=da]
             ]
           )
       end

spec/lib/http/options/headers_spec.rb

@@ -8,7 +8,7 @@
   end
 
   it "may be specified with with_headers" do
-    opts2 = opts.with_headers("accept" => "json")
+    opts2 = opts.with_headers(:accept => "json")
     expect(opts.headers).to be_empty
     expect(opts2.headers).to eq([%w[Accept json]])
   end

spec/lib/http/request/writer_spec.rb

@@ -22,6 +22,18 @@
       end
     end
 
+    context "when headers are specified as strings with mixed case" do
+      let(:headers) { HTTP::Headers.coerce "content-Type" => "text", "X_MAX" => "200" }
+
+      it "writes the headers with the same casing" do
+        writer.stream
+        expect(io.string).to eq [
+          "#{headerstart}\r\n",
+          "content-Type: text\r\nX_MAX: 200\r\nContent-Length: 0\r\n\r\n"
+        ].join
+      end
+    end
+
     context "when body is nonempty" do
       let(:body) { HTTP::Request::Body.new("content") }