config: typo fix for distinct-agg-push-down (#24011)

config/config.go

@@ -419,7 +419,7 @@ type Performance struct {
 	TCPNoDelay            bool    `toml:"tcp-no-delay" json:"tcp-no-delay"`
 	CrossJoin             bool    `toml:"cross-join" json:"cross-join"`
 	RunAutoAnalyze        bool    `toml:"run-auto-analyze" json:"run-auto-analyze"`
-	DistinctAggPushDown   bool    `toml:"distinct-agg-push-down" json:"agg-push-down-join"`
+	DistinctAggPushDown   bool    `toml:"distinct-agg-push-down" json:"distinct-agg-push-down"`
 	CommitterConcurrency  int     `toml:"committer-concurrency" json:"committer-concurrency"`
 	MaxTxnTTL             uint64  `toml:"max-txn-ttl" json:"max-txn-ttl"`
 	MemProfileInterval    string  `toml:"mem-profile-interval" json:"mem-profile-interval"`

config/config_test.go

@@ -18,6 +18,7 @@ import (
 	"os"
 	"os/user"
 	"path/filepath"
+	"reflect"
 	"runtime"
 	"testing"
 
@@ -423,6 +424,14 @@ xkNuJ2BlEGkwWLiRbKy1lNBBFUXKuhh3L/EIY10WTnr3TQzeL6H1
 	// is recycled when the reference count drops to 0.
 	c.Assert(os.Remove(certFile), IsNil)
 	c.Assert(os.Remove(keyFile), IsNil)
+
+	// test for config `toml` and `json` tag names
+	c1 := Config{}
+	st := reflect.TypeOf(c1)
+	for i := 0; i < st.NumField(); i++ {
+		field := st.Field(i)
+		c.Assert(field.Tag.Get("toml"), Equals, field.Tag.Get("json"))
+	}
 }
 
 func (s *testConfigSuite) TestOOMActionValid(c *C) {