puts: Make it more compatible to MRI

- puts calls #to_ary on non-String objects, without checking its existance beforehand. This behavior is copied for cases where the receiver has a #method_missing in place that catches this call - If puts calls #to_s, and #to_s does not return a string (e.g. some bogus override of #to_s), it outputs generic object infos (Class name and address)
rubinius · Jan 10, 2016 · 135145a · 135145a
1 parent 179b77b
commit 135145a
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Showing 2 changed files with 30 additions and 7 deletions.
diff --git a/kernel/common/io.rb b/kernel/common/io.rb
@@ -1793,16 +1793,20 @@ def puts(*args)
       args.each do |arg|
         if arg.equal? nil
           str = ""
+        elsif arg.kind_of? String
+          str = arg
         elsif Thread.guarding? arg
           str = "[...]"
-        elsif arg.respond_to?(:to_ary)
+        else
           Thread.recursion_guard arg do
-            arg.to_ary.each do |a|
-              puts a
+            begin
+              arg.to_ary.each { |a| puts a }
+            rescue NoMethodError
+              unless (str = arg.to_s).kind_of? String
+                str = "#<#{arg.class}:0x#{arg.object_id.to_s(16)}>"
+              end
             end
           end
-        else
-          str = arg.to_s
         end
 
         if str

diff --git a/spec/ruby/core/io/puts_spec.rb b/spec/ruby/core/io/puts_spec.rb
@@ -37,7 +37,17 @@
     @io.puts(nil, nil).should == nil
   end
 
-  it "calls to_ary before writing non-string objects that respond to :to_ary" do
+  it "calls :to_ary before writing non-string objects, regardless of it being implemented in the receiver" do
+    object = mock('hola')
+    object.should_receive(:method_missing).with(:to_ary)
+    object.should_receive(:to_s).and_return("#<Object:0x...>")
+
+    @io.should_receive(:write).with("#<Object:0x...>")
+    @io.should_receive(:write).with("\n")
+    @io.puts(object).should == nil
+  end
+
+  it "calls :to_ary before writing non-string objects" do
     object = mock('hola')
     object.should_receive(:to_ary).and_return(["hola"])
 
@@ -46,7 +56,7 @@
     @io.puts(object).should == nil
   end
 
-  it "calls to_s before writing non-string objects that don't respond to :to_ary" do
+  it "calls :to_s before writing non-string objects that don't respond to :to_ary" do
     object = mock('hola')
     object.should_receive(:to_s).and_return("hola")
 
@@ -55,6 +65,15 @@
     @io.puts(object).should == nil
   end
 
+  it "returns general object info if :to_s does not return a string" do
+    object = mock('hola')
+    object.should_receive(:to_s).and_return(false)
+
+    @io.should_receive(:write).with(object.inspect.split(" ")[0] + ">")
+    @io.should_receive(:write).with("\n")
+    @io.puts(object).should == nil
+  end
+
   it "writes each arg if given several" do
     @io.should_receive(:write).with("1")
     @io.should_receive(:write).with("two")