From 418bc94b295716f9ee88d2df02d14627dfd09937 Mon Sep 17 00:00:00 2001
From: TSUYUSATO Kitsune <make.just.on@gmail.com>
Date: Thu, 13 Jun 2024 14:55:32 +0900
Subject: [PATCH 1/3] Improve `Element#attribute` as 6500x faster

`Element#namespaces` is heavy method because this method needs to
traverse all ancestors of the element. `Element#attribute` calls
`namespaces` redundantly, so it is much slower.

This commit reduces `namespaces` calls in `Element#attribute`.
Also, this commit removes a redundant `respond_to?` because
`namespaces` must return `Hash` in the current implementation.
---
 benchmark/attribute.yaml | 43 ++++++++++++++++++++++++++++++++++++++++
 lib/rexml/element.rb     |  9 ++-------
 2 files changed, 45 insertions(+), 7 deletions(-)
 create mode 100644 benchmark/attribute.yaml

diff --git a/benchmark/attribute.yaml b/benchmark/attribute.yaml
new file mode 100644
index 00000000..b1325106
--- /dev/null
+++ b/benchmark/attribute.yaml
@@ -0,0 +1,43 @@
+loop_count: 1000
+contexts:
+  - gems:
+      rexml: 3.2.6
+    require: false
+    prelude: require 'rexml'
+  - name: master
+    prelude: |
+      $LOAD_PATH.unshift(File.expand_path("lib"))
+      require 'rexml'
+  - name: 3.2.6(YJIT)
+    gems:
+      rexml: 3.2.6
+    require: false
+    prelude: |
+      require 'rexml'
+      RubyVM::YJIT.enable
+  - name: master(YJIT)
+    prelude: |
+      $LOAD_PATH.unshift(File.expand_path("lib"))
+      require 'rexml'
+      RubyVM::YJIT.enable
+
+prelude: |
+  require 'rexml/document'
+
+  xml_source = "<deepest x:with_ns='foo' without_ns='bar'></deepest>"
+  100.times do
+    xml_source = "<nest>#{xml_source}</nest>"
+  end
+  xml_source = "<root xmlns:x='xyz'>#{xml_source}</root>"
+
+  document = REXML::Document.new(xml_source)
+  deepest_node = document.root
+  until deepest_node.elements.size.zero?
+    deepest_node = deepest_node.elements.first
+  end
+
+benchmark:
+  attribute_with_ns: |
+    deepest_node.attribute("with_ns", "xyz")
+  attribute_without_ns: |
+    deepest_node.attribute("without_ns")
diff --git a/lib/rexml/element.rb b/lib/rexml/element.rb
index 2899759d..a5808d7c 100644
--- a/lib/rexml/element.rb
+++ b/lib/rexml/element.rb
@@ -1276,16 +1276,11 @@ def [](name_or_index)
     #   document.root.attribute("x", "a") # => a:x='a:x'
     #
     def attribute( name, namespace=nil )
-      prefix = nil
-      if namespaces.respond_to? :key
-        prefix = namespaces.key(namespace) if namespace
-      else
-        prefix = namespaces.index(namespace) if namespace
-      end
+      prefix = namespaces.key(namespace) if namespace
       prefix = nil if prefix == 'xmlns'
 
       ret_val =
-        attributes.get_attribute( "#{prefix ? prefix + ':' : ''}#{name}" )
+        attributes.get_attribute( prefix ? "#{prefix}:#{name}" : name )
 
       return ret_val unless ret_val.nil?
       return nil if prefix.nil?

From 53c6d5fa85df7976bd559ccc5618686acaacbec9 Mon Sep 17 00:00:00 2001
From: Hiroya Fujinami <make.just.on@gmail.com>
Date: Thu, 13 Jun 2024 15:32:59 +0900
Subject: [PATCH 2/3] Update benchmark/attribute.yaml

Co-authored-by: Sutou Kouhei <kou@cozmixng.org>
---
 benchmark/attribute.yaml | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/benchmark/attribute.yaml b/benchmark/attribute.yaml
index b1325106..812329be 100644
--- a/benchmark/attribute.yaml
+++ b/benchmark/attribute.yaml
@@ -31,10 +31,7 @@ prelude: |
   xml_source = "<root xmlns:x='xyz'>#{xml_source}</root>"
 
   document = REXML::Document.new(xml_source)
-  deepest_node = document.root
-  until deepest_node.elements.size.zero?
-    deepest_node = deepest_node.elements.first
-  end
+  deepest_node = document.elements["//deepest"]
 
 benchmark:
   attribute_with_ns: |

From 39f77cead5962be7e8d7523968a703183ad3bef5 Mon Sep 17 00:00:00 2001
From: TSUYUSATO Kitsune <make.just.on@gmail.com>
Date: Thu, 13 Jun 2024 15:35:26 +0900
Subject: [PATCH 3/3] Update benchmark names

---
 benchmark/attribute.yaml | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/benchmark/attribute.yaml b/benchmark/attribute.yaml
index 812329be..5dd7fded 100644
--- a/benchmark/attribute.yaml
+++ b/benchmark/attribute.yaml
@@ -34,7 +34,5 @@ prelude: |
   deepest_node = document.elements["//deepest"]
 
 benchmark:
-  attribute_with_ns: |
-    deepest_node.attribute("with_ns", "xyz")
-  attribute_without_ns: |
-    deepest_node.attribute("without_ns")
+  with_ns:    deepest_node.attribute("with_ns", "xyz")
+  without_ns: deepest_node.attribute("without_ns")