improve each_pair and each destructuring

rubys · rubys · commit 5000ed97521b · 2019-08-18T17:24:32.000-04:00
diff --git a/lib/ruby2js/filter/functions.rb b/lib/ruby2js/filter/functions.rb
@@ -534,13 +534,24 @@ def on_block(node)
             call.children[0].children[0], node.children[2])
 
         elsif
-          [:each, :each_value].include? method and
-          node.children[1].children.length == 1
+          [:each, :each_value].include? method
         then
           if es2015
-            process node.updated(:for_of,
-              [s(:lvasgn, node.children[1].children[0].children[0]),
-              node.children[0].children[0], node.children[2]])
+            if node.children[1].children.length > 1
+              process node.updated(:for_of,
+                [s(:mlhs, *node.children[1].children.map {|child|
+                  s(:lvasgn, child.children[0])}),
+                node.children[0].children[0], node.children[2]])
+            elsif node.children[1].children[0].type == :mlhs
+              process node.updated(:for_of,
+                [s(:mlhs, *node.children[1].children[0].children.map {|child|
+                  s(:lvasgn, child.children[0])}),
+                node.children[0].children[0], node.children[2]])
+            else
+              process node.updated(:for_of,
+                [s(:lvasgn, node.children[1].children[0].children[0]),
+                node.children[0].children[0], node.children[2]])
+            end
           elsif method == :each
             process node.updated(nil, [s(:send, call.children[0],
               :forEach), *node.children[1..2]])
@@ -572,8 +583,8 @@ def on_block(node)
           if es2017
             # Object.entries(a).forEach(([key, value]) => {})
             process node.updated(nil, [s(:send, s(:send,
-            s(:const, nil, :Object), :entries, call.children[0]), :forEach),
-            s(:args, s(:mlhs, *node.children[1].children)), node.children[2]])
+            s(:const, nil, :Object), :entries, call.children[0]), :each),
+            node.children[1], node.children[2]])
           else
             # Object.keys(a).forEach(function(key) {var value = a[key]; ...})
             process node.updated(nil, [s(:send, s(:send, 
diff --git a/spec/es2015_spec.rb b/spec/es2015_spec.rb
@@ -76,6 +76,11 @@ def to_js_fn(string)
         must_equal 'for (let v of a) {x += v}'
     end
 
+    it "should convert array.each multiple to a for...of" do
+      to_js_fn( 'a.each {|(v,w)| x+=v}' ).
+        must_equal 'for (let [v, w] of a) {x += v}'
+    end
+
     it "should handle conditional returns in an each block" do
       to_js_fn( 'a.each {|i| return i if true}' ).
         must_equal 'for (let i of a) {if (true) return i}'
diff --git a/spec/es2017_spec.rb b/spec/es2017_spec.rb
@@ -25,7 +25,7 @@ def to_js_fn(string)
   describe :Hash do
     it "should convert hash.each_pair" do
       to_js_fn( 'h.each_pair {|k,v| x+=v}' ).
-        must_equal 'Object.entries(h).forEach(([k, v]) => {x += v})'
+        must_equal 'for (let [k, v] of Object.entries(h)) {x += v}'
     end
 
     it "should convert hash.entries()" do
