parse.y: rescue modifier in rhs of op asgn

* parse.y (stmt, arg): rescue modifier in command op assignment
  should be limited to rhs only.  [ruby-core:75621] [Bug #12402]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@55887 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

3 files changed, 97 insertions, 20 deletions

diff --git a/ChangeLog b/ChangeLog
index 8431ecfb4b..01a0bc4063 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sat Aug 13 10:52:19 2016  Nobuyoshi Nakada  <[email protected]>
+
+	* parse.y (stmt, arg): rescue modifier in command op assignment
+	  should be limited to rhs only.  [ruby-core:75621] [Bug #12402]
+
 Sat Aug 13 07:51:40 2016  Masaki Suketa <[email protected]>
 
 	* ext/win32ole/win32ole.c (ole_val2variant): fix integer conversion in
diff --git a/parse.y b/parse.y
index afe56e5664..41a164c02a 100644
--- a/parse.y
+++ b/parse.y
@@ -1284,12 +1284,12 @@ stmt		: keyword_alias fitem {SET_LEX_STATE(EXPR_FNAME|EXPR_FITEM);} fitem
 			$$ = dispatch2(massign, $1, $3);
 		    %*/
 		    }
-		| var_lhs tOP_ASGN command_call
+		| var_lhs tOP_ASGN command_rhs
 		    {
 			value_expr($3);
 			$$ = new_op_assign($1, $2, $3);
 		    }
-		| primary_value '[' opt_call_args rbracket tOP_ASGN command_call
+		| primary_value '[' opt_call_args rbracket tOP_ASGN command_rhs
 		    {
 		    /*%%%*/
 			NODE *args;
@@ -1310,27 +1310,27 @@ stmt		: keyword_alias fitem {SET_LEX_STATE(EXPR_FNAME|EXPR_FITEM);} fitem
 			$$ = dispatch3(opassign, $$, $5, $6);
 		    %*/
 		    }
-		| primary_value call_op tIDENTIFIER tOP_ASGN command_call
+		| primary_value call_op tIDENTIFIER tOP_ASGN command_rhs
 		    {
 			value_expr($5);
 			$$ = new_attr_op_assign($1, $2, $3, $4, $5);
 		    }
-		| primary_value call_op tCONSTANT tOP_ASGN command_call
+		| primary_value call_op tCONSTANT tOP_ASGN command_rhs
 		    {
 			value_expr($5);
 			$$ = new_attr_op_assign($1, $2, $3, $4, $5);
 		    }
-		| primary_value tCOLON2 tCONSTANT tOP_ASGN command_call
+		| primary_value tCOLON2 tCONSTANT tOP_ASGN command_rhs
 		    {
 			$$ = const_path_field($1, $3);
 			$$ = new_const_op_assign($$, $4, $5);
 		    }
-		| primary_value tCOLON2 tIDENTIFIER tOP_ASGN command_call
+		| primary_value tCOLON2 tIDENTIFIER tOP_ASGN command_rhs
 		    {
 			value_expr($5);
 			$$ = new_attr_op_assign($1, idCOLON2, $3, $4, $5);
 		    }
-		| backref tOP_ASGN command_call
+		| backref tOP_ASGN command_rhs
 		    {
 			$1 = var_field($1);
 			$$ = backref_assign_error($1, node_assign($1, $3));
@@ -2002,7 +2002,7 @@ arg		: lhs '=' arg_rhs
 		    {
 			$$ = new_op_assign($1, $2, $3);
 		    }
-		| primary_value '[' opt_call_args rbracket tOP_ASGN arg
+		| primary_value '[' opt_call_args rbracket tOP_ASGN arg_rhs
 		    {
 		    /*%%%*/
 			NODE *args;
@@ -2028,32 +2028,32 @@ arg		: lhs '=' arg_rhs
 			$$ = dispatch3(opassign, $1, $5, $6);
 		    %*/
 		    }
-		| primary_value call_op tIDENTIFIER tOP_ASGN arg
+		| primary_value call_op tIDENTIFIER tOP_ASGN arg_rhs
 		    {
 			value_expr($5);
 			$$ = new_attr_op_assign($1, $2, $3, $4, $5);
 		    }
-		| primary_value call_op tCONSTANT tOP_ASGN arg
+		| primary_value call_op tCONSTANT tOP_ASGN arg_rhs
 		    {
 			value_expr($5);
 			$$ = new_attr_op_assign($1, $2, $3, $4, $5);
 		    }
-		| primary_value tCOLON2 tIDENTIFIER tOP_ASGN arg
+		| primary_value tCOLON2 tIDENTIFIER tOP_ASGN arg_rhs
 		    {
 			value_expr($5);
 			$$ = new_attr_op_assign($1, idCOLON2, $3, $4, $5);
 		    }
-		| primary_value tCOLON2 tCONSTANT tOP_ASGN arg
+		| primary_value tCOLON2 tCONSTANT tOP_ASGN arg_rhs
 		    {
 			$$ = const_path_field($1, $3);
 			$$ = new_const_op_assign($$, $4, $5);
 		    }
-		| tCOLON3 tCONSTANT tOP_ASGN arg
+		| tCOLON3 tCONSTANT tOP_ASGN arg_rhs
 		    {
 			$$ = top_const_field($2);
 			$$ = new_const_op_assign($$, $3, $4);
 		    }
-		| backref tOP_ASGN arg
+		| backref tOP_ASGN arg_rhs
 		    {
 			$1 = var_field($1);
 			$$ = backref_assign_error($1, new_op_assign($1, $2, $3));
diff --git a/test/ruby/test_parse.rb b/test/ruby/test_parse.rb
index 7f0177819e..434533fcab 100644
--- a/test/ruby/test_parse.rb
+++ b/test/ruby/test_parse.rb
@@ -876,12 +876,84 @@ x = __ENCODING__
 
   def test_rescue_in_command_assignment
     bug = '[ruby-core:75621] [Bug #12402]'
-    v = bug
-    v = raise(v) rescue "ok"
-    assert_equal("ok", v)
-    v = bug
-    v = raise v rescue "ok"
-    assert_equal("ok", v)
+    all_assertions(bug) do |a|
+      a.for("lhs = arg") do
+        v = bug
+        v = raise(bug) rescue "ok"
+        assert_equal("ok", v)
+      end
+      a.for("lhs op_asgn arg") do
+        v = 0
+        v += raise(bug) rescue 1
+        assert_equal(1, v)
+      end
+      a.for("lhs[] op_asgn arg") do
+        v = [0]
+        v[0] += raise(bug) rescue 1
+        assert_equal([1], v)
+      end
+      a.for("lhs.m op_asgn arg") do
+        k = Struct.new(:m)
+        v = k.new(0)
+        v.m += raise(bug) rescue 1
+        assert_equal(k.new(1), v)
+      end
+      a.for("lhs::m op_asgn arg") do
+        k = Struct.new(:m)
+        v = k.new(0)
+        v::m += raise(bug) rescue 1
+        assert_equal(k.new(1), v)
+      end
+      a.for("lhs.C op_asgn arg") do
+        k = Struct.new(:C)
+        v = k.new(0)
+        v.C += raise(bug) rescue 1
+        assert_equal(k.new(1), v)
+      end
+      a.for("lhs::C op_asgn arg") do
+        v = Class.new
+        v::C ||= raise(bug) rescue 1
+        assert_equal(1, v::C)
+      end
+      a.for("lhs = command") do
+        v = bug
+        v = raise bug rescue "ok"
+        assert_equal("ok", v)
+      end
+      a.for("lhs op_asgn command") do
+        v = 0
+        v += raise bug rescue 1
+        assert_equal(1, v)
+      end
+      a.for("lhs[] op_asgn command") do
+        v = [0]
+        v[0] += raise bug rescue 1
+        assert_equal([1], v)
+      end
+      a.for("lhs.m op_asgn command") do
+        k = Struct.new(:m)
+        v = k.new(0)
+        v.m += raise bug rescue 1
+        assert_equal(k.new(1), v)
+      end
+      a.for("lhs::m op_asgn command") do
+        k = Struct.new(:m)
+        v = k.new(0)
+        v::m += raise bug rescue 1
+        assert_equal(k.new(1), v)
+      end
+      a.for("lhs.C op_asgn command") do
+        k = Struct.new(:C)
+        v = k.new(0)
+        v.C += raise bug rescue 1
+        assert_equal(k.new(1), v)
+      end
+      a.for("lhs::C op_asgn command") do
+        v = Class.new
+        v::C ||= raise bug rescue 1
+        assert_equal(1, v::C)
+      end
+    end
   end
 
 =begin