Merge pull request pingcap#192 from pingcap/shenli/builtin-info

expressions: Extract builtin information functions to builtin_info.go

expression/expressions/builtin.go

@@ -22,9 +22,6 @@ import (
 	"strings"
 
 	"github.com/juju/errors"
-	"github.com/pingcap/tidb/context"
-	"github.com/pingcap/tidb/sessionctx/db"
-	"github.com/pingcap/tidb/sessionctx/variable"
 )
 
 var builtin = map[string]struct {
@@ -109,26 +106,3 @@ func builtinCoalesce(args []interface{}, ctx map[interface{}]interface{}) (v int
 	}
 	return nil, nil
 }
-
-func builtinDatabase(args []interface{}, data map[interface{}]interface{}) (v interface{}, err error) {
-	c, ok := data[ExprEvalArgCtx]
-	if !ok {
-		return nil, errors.Errorf("Missing ExprEvalArgCtx when evalue builtin")
-	}
-	ctx := c.(context.Context)
-	d := db.GetCurrentSchema(ctx)
-	if d == "" {
-		return nil, nil
-	}
-	return d, nil
-}
-
-// See: https://dev.mysql.com/doc/refman/5.7/en/information-functions.html#function_found-rows
-func builtinFoundRows(arg []interface{}, data map[interface{}]interface{}) (interface{}, error) {
-	c, ok := data[ExprEvalArgCtx]
-	if !ok {
-		return nil, errors.Errorf("Missing ExprEvalArgCtx when evalue builtin")
-	}
-	ctx := c.(context.Context)
-	return variable.GetSessionVars(ctx).FoundRows, nil
-}

expression/expressions/builtin_info.go

@@ -0,0 +1,49 @@
+// Copyright 2013 The ql Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSES/QL-LICENSE file.
+
+// Copyright 2015 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expressions
+
+import (
+	"github.com/juju/errors"
+	"github.com/pingcap/tidb/context"
+	"github.com/pingcap/tidb/sessionctx/db"
+	"github.com/pingcap/tidb/sessionctx/variable"
+)
+
+// See: https://dev.mysql.com/doc/refman/5.7/en/information-functions.html
+
+func builtinDatabase(args []interface{}, data map[interface{}]interface{}) (v interface{}, err error) {
+	c, ok := data[ExprEvalArgCtx]
+	if !ok {
+		return nil, errors.Errorf("Missing ExprEvalArgCtx when evalue builtin")
+	}
+	ctx := c.(context.Context)
+	d := db.GetCurrentSchema(ctx)
+	if d == "" {
+		return nil, nil
+	}
+	return d, nil
+}
+
+func builtinFoundRows(arg []interface{}, data map[interface{}]interface{}) (interface{}, error) {
+	c, ok := data[ExprEvalArgCtx]
+	if !ok {
+		return nil, errors.Errorf("Missing ExprEvalArgCtx when evalue builtin")
+	}
+	ctx := c.(context.Context)
+	return variable.GetSessionVars(ctx).FoundRows, nil
+}

expression/expressions/builtin_info_test.go

@@ -0,0 +1,56 @@
+// Copyright 2015 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expressions
+
+import (
+	. "github.com/pingcap/check"
+	"github.com/pingcap/tidb/sessionctx/db"
+	"github.com/pingcap/tidb/sessionctx/variable"
+)
+
+var _ = Suite(&testBuiltinInfoSuite{})
+
+type testBuiltinInfoSuite struct {
+}
+
+func (s *testBuiltinSuite) TestDatabase(c *C) {
+	ctx := newMockCtx()
+	m := map[interface{}]interface{}{}
+	v, err := builtinDatabase(nil, m)
+	c.Assert(err, NotNil)
+
+	m[ExprEvalArgCtx] = ctx
+	v, err = builtinDatabase(nil, m)
+	c.Assert(err, IsNil)
+	c.Assert(v, IsNil)
+
+	db.BindCurrentSchema(ctx, "test")
+	v, err = builtinDatabase(nil, m)
+	c.Assert(err, IsNil)
+	c.Assert(v, Equals, "test")
+}
+
+func (s *testBuiltinSuite) TestFoundRows(c *C) {
+	ctx := newMockCtx()
+	m := map[interface{}]interface{}{}
+	v, err := builtinFoundRows(nil, m)
+	c.Assert(err, NotNil)
+
+	variable.BindSessionVars(ctx)
+
+	m[ExprEvalArgCtx] = ctx
+	v, err = builtinFoundRows(nil, m)
+	c.Assert(err, IsNil)
+	c.Assert(v, Equals, uint64(0))
+}

expression/expressions/builtin_test.go

@@ -15,8 +15,6 @@ package expressions
 
 import (
 	. "github.com/pingcap/check"
-	"github.com/pingcap/tidb/sessionctx/db"
-	"github.com/pingcap/tidb/sessionctx/variable"
 )
 
 var _ = Suite(&testBuiltinSuite{})
@@ -43,34 +41,3 @@ func (s *testBuiltinSuite) TestCoalesce(c *C) {
 	c.Assert(err, IsNil)
 	c.Assert(v, IsNil)
 }
-
-func (s *testBuiltinSuite) TestDatabase(c *C) {
-	ctx := newMockCtx()
-	m := map[interface{}]interface{}{}
-	v, err := builtinDatabase(nil, m)
-	c.Assert(err, NotNil)
-
-	m[ExprEvalArgCtx] = ctx
-	v, err = builtinDatabase(nil, m)
-	c.Assert(err, IsNil)
-	c.Assert(v, IsNil)
-
-	db.BindCurrentSchema(ctx, "test")
-	v, err = builtinDatabase(nil, m)
-	c.Assert(err, IsNil)
-	c.Assert(v, Equals, "test")
-}
-
-func (s *testBuiltinSuite) TestFoundRows(c *C) {
-	ctx := newMockCtx()
-	m := map[interface{}]interface{}{}
-	v, err := builtinFoundRows(nil, m)
-	c.Assert(err, NotNil)
-
-	variable.BindSessionVars(ctx)
-
-	m[ExprEvalArgCtx] = ctx
-	v, err = builtinFoundRows(nil, m)
-	c.Assert(err, IsNil)
-	c.Assert(v, Equals, uint64(0))
-}