Merge pull request #1707 from Fleurer/issue1706

keep stack with nlocals instead of nregs; fix #1706

mrbgems/mruby-bin-mirb/bintest/mirb.rb

@@ -10,3 +10,26 @@ assert('regression for #1563') do
   o, s = Open3.capture2('bin/mirb', :stdin_data => "a=1;b=2;c=3\nb\nc")
   assert_true o.include?('=> 3')
 end
+
+assert('regression for #1706') do
+  o, s = Open3.capture2('bin/mirb', :stdin_data => %{
+    if false
+      a = 1
+      b = 1
+    end
+    puts "a: \#{a.inspect}"
+    puts "b: \#{b.inspect}"
+  })
+  assert_true o.include?('a: nil')
+  assert_true o.include?('b: nil')
+
+  o, s = Open3.capture2('bin/mirb', :stdin_data => %{
+    a = 1
+    b = 2
+    if false
+      c = 3
+    end
+    puts "c: \#{c.inspect}"
+  })
+  assert_true o.include?('c: nil')
+end

mrbgems/mruby-bin-mirb/tools/mirb/mirb.c

@@ -251,8 +251,7 @@ main(int argc, char **argv)
   int n;
   mrb_bool code_block_open = FALSE;
   int ai;
-  mrb_bool first_command = TRUE;
-  unsigned int nregs;
+  unsigned int stack_keep = 0;
 
   /* new interpreter instance */
   mrb = mrb_open();
@@ -365,12 +364,12 @@ main(int argc, char **argv)
           mrb_codedump_all(mrb, proc);
         }
         /* pass a proc for evaulation */
-        nregs = first_command ? 0: proc->body.irep->nregs;
         /* evaluate the bytecode */
         result = mrb_context_run(mrb,
             proc,
             mrb_top_self(mrb),
-            nregs);
+            stack_keep);
+        stack_keep = proc->body.irep->nlocals;
         /* did an exception occur? */
         if (mrb->exc) {
           p(mrb, mrb_obj_value(mrb->exc), 0);
@@ -390,7 +389,6 @@ main(int argc, char **argv)
     }
     mrb_parser_free(parser);
     cxt->lineno++;
-    first_command = FALSE;
   }
   mrbc_context_free(mrb, cxt);
   mrb_close(mrb);