TestDAGPlanBuilderUnionScan is a break test

[hawkingrei]

Bug Report

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tidb/planner/core/physical_plan_test.go

Lines 361 to 374 in 6b8cf9d

	func TestDAGPlanBuilderUnionScan(t *testing.T) {
	store := testkit.CreateMockStore(t)
	tk := testkit.NewTestKit(t, store)
	tk.MustExec("use test")
	var input []string
	var output []struct {
	SQL string
	Best string
	}
	p := parser.New()
	is := infoschema.MockInfoSchema([]*model.TableInfo{core.MockSignedTable(), core.MockUnsignedTable()})
	for i, tt := range input {

TestDAGPlanBuilderUnionScan forget to load the test data. so it always passes to test.

1. Minimal reproduce step (Required)

2. What did you expect to see? (Required)

3. What did you see instead (Required)

4. What is your TiDB version? (Required)

[hawkingrei]

In the nogo_config.json, we have an config about this problem.

"planner/core/physical_plan_test.go": "please fix it",

after you fix it, Please remove it.

[chrysan]

/assign @fzzf678

[ti-chi-bot]

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/assign @fzzf678

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[fzzf678]

/assign