From 6cd4371034bd08f67d05cd89d9c4523a1075ad77 Mon Sep 17 00:00:00 2001
From: Ostap Brehin <osbre@protonmail.com>
Date: Tue, 30 Jul 2024 06:27:19 +0100
Subject: [PATCH] Fix conversion of multiple `<<` to multiple `.push` calls

---
 lib/ruby2js/converter/send.rb | 24 ++++++++++++++++++++++--
 spec/transliteration_spec.rb  |  8 ++++++--
 2 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/lib/ruby2js/converter/send.rb b/lib/ruby2js/converter/send.rb
index fec5a6de..312c6555 100644
--- a/lib/ruby2js/converter/send.rb
+++ b/lib/ruby2js/converter/send.rb
@@ -233,8 +233,28 @@ class Converter
       elsif method == :!~
         put '!'; parse args.first; put '.test('; parse receiver; put ')'
 
-      elsif method == :<< and args.length == 1 and @state == :statement
-        parse receiver; put '.push('; parse args.first; put ')'
+      elsif method == :<<
+        if @state == :statement
+          # Handle chained << operations by converting them to push() method calls
+          current = receiver
+          operations = [args.first]
+
+          # Traverse the AST to collect all chained << operations
+          while current.type == :send && current.children[1] == :<<
+            operations.unshift(current.children[2])
+            current = current.children[0]
+          end
+
+          # Generate a series of push() calls for each operation in the chain
+          operations.each do |arg|
+            parse current ; put '.push(' ; parse arg ; put ')'
+            put '; ' unless arg == operations.last
+          end
+        else
+          # If not in statement context, fall back to original behavior
+          group_receiver ? group(receiver) : parse(receiver)
+          put " << " ; group_target ? group(args.first) : parse(args.first)
+        end
 
       elsif method == :<=>
         parse receiver; put ' < '; parse args.first; put ' ? -1 : '
diff --git a/spec/transliteration_spec.rb b/spec/transliteration_spec.rb
index 471a3e76..7b838744 100644
--- a/spec/transliteration_spec.rb
+++ b/spec/transliteration_spec.rb
@@ -364,12 +364,16 @@ def to_js( string, opts={} )
       to_js('x = ()').must_equal 'var x = null'
     end
   end
-  
+
   describe 'array push' do
     it "should convert << statements to .push calls" do
       to_js( 'a << b' ).must_equal 'a.push(b)'
     end
-    
+
+    it "should convert multiple << statements to multiple .push calls" do
+      to_js( 'a << b << c << d << e' ).must_equal 'a.push(b); a.push(c); a.push(d); a.push(e)'
+    end
+
     it "should leave << expressions alone" do
       to_js( 'y = a << b' ).must_equal 'var y = a << b'
     end