parser,config: Correct handling of display width deprecation except for zerofill and tinyint(1) (#46651)

close pingcap/tidb#46650

executor/test/showtest/show_test.go

@@ -1647,12 +1647,22 @@ func TestShowCreateTableWithIntegerDisplayLengthWarnings(t *testing.T) {
 	tk.MustQuery("show warnings").Check(testkit.Rows("Warning 1064 You have an error in your SQL syntax; check the manual that corresponds to your TiDB version for the right syntax to use [parser:1681]Integer display width is deprecated and will be removed in a future release.",
 		"Warning 1064 You have an error in your SQL syntax; check the manual that corresponds to your TiDB version for the right syntax to use [parser:1681]Integer display width is deprecated and will be removed in a future release."))
 	tk.MustQuery("show create table t").Check(testkit.Rows("t CREATE TABLE `t` (\n" +
-		"  `a` tinyint DEFAULT NULL,\n" +
+		"  `a` tinyint(1) DEFAULT NULL,\n" +
 		"  `b` smallint DEFAULT NULL,\n" +
 		"  `c` mediumint DEFAULT NULL,\n" +
 		"  `d` int DEFAULT NULL,\n" +
 		"  `e` bigint DEFAULT NULL\n" +
 		") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"))
+
+	tk.MustExec("drop table if exists t")
+	tk.MustExec("create table t(id int primary key, c1 bool, c2 int(10) zerofill)")
+	tk.MustQuery("show warnings").Check(testkit.Rows("Warning 1064 You have an error in your SQL syntax; check the manual that corresponds to your TiDB version for the right syntax to use [parser:1681]Integer display width is deprecated and will be removed in a future release."))
+	tk.MustQuery("show create table t").Check(testkit.Rows("t CREATE TABLE `t` (\n" +
+		"  `id` int NOT NULL,\n" +
+		"  `c1` tinyint(1) DEFAULT NULL,\n" +
+		"  `c2` int(10) unsigned zerofill DEFAULT NULL,\n" +
+		"  PRIMARY KEY (`id`) /*T![clustered_index] CLUSTERED */\n" +
+		") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"))
 }
 
 func TestShowVar(t *testing.T) {

parser/types/BUILD.bazel

@@ -27,7 +27,7 @@ go_test(
     ],
     embed = [":types"],
     flaky = True,
-    shard_count = 5,
+    shard_count = 6,
     deps = [
         "//parser",
         "//parser/ast",

parser/types/field_type.go

@@ -409,10 +409,20 @@ func (ft *FieldType) CompactStr() string {
 		suffix = fmt.Sprintf("(%d,%d)", displayFlen, displayDecimal)
 	case mysql.TypeBit, mysql.TypeVarchar, mysql.TypeString, mysql.TypeVarString:
 		suffix = fmt.Sprintf("(%d)", displayFlen)
-	case mysql.TypeTiny, mysql.TypeShort, mysql.TypeInt24, mysql.TypeLong, mysql.TypeLonglong:
+	case mysql.TypeTiny:
+		// With display length deprecation active tinyint(1) still has
+		// a display length to indicate this might have been a BOOL.
+		// Connectors expect this.
+		//
+		// See also:
+		// https://dev.mysql.com/doc/relnotes/mysql/8.0/en/news-8-0-19.html
+		if !TiDBStrictIntegerDisplayWidth || (mysql.HasZerofillFlag(ft.flag) || displayFlen == 1) {
+			suffix = fmt.Sprintf("(%d)", displayFlen)
+		}
+	case mysql.TypeShort, mysql.TypeInt24, mysql.TypeLong, mysql.TypeLonglong:
 		// Referring this issue #6688, the integer max display length is deprecated in MySQL 8.0.
 		// Since the length doesn't take any effect in TiDB storage or showing result, we remove it here.
-		if !TiDBStrictIntegerDisplayWidth {
+		if !TiDBStrictIntegerDisplayWidth || mysql.HasZerofillFlag(ft.flag) {
 			suffix = fmt.Sprintf("(%d)", displayFlen)
 		}
 	case mysql.TypeYear:

parser/types/field_type_test.go

@@ -299,3 +299,33 @@ func TestFieldTypeEqual(t *testing.T) {
 	ft1.SetFlen(23)
 	require.Equal(t, true, ft1.Equal(ft2))
 }
+
+func TestCompactStr(t *testing.T) {
+	cases := []struct {
+		t     byte   // Field Type
+		flen  int    // Field Length
+		flags uint   // Field Flags, e.g. ZEROFILL
+		e1    string // Expected string with TiDBStrictIntegerDisplayWidth disabled
+		e2    string // Expected string with TiDBStrictIntegerDisplayWidth enabled
+	}{
+		// TINYINT(1) is considered a bool by connectors, this should always display
+		// the display length.
+		{mysql.TypeTiny, 1, 0, `tinyint(1)`, `tinyint(1)`},
+		{mysql.TypeTiny, 2, 0, `tinyint(2)`, `tinyint`},
+
+		// If the ZEROFILL flag is set the display length should not be hidden.
+		{mysql.TypeLong, 10, 0, `int(10)`, `int`},
+		{mysql.TypeLong, 10, mysql.ZerofillFlag, `int(10)`, `int(10)`},
+	}
+	for _, cc := range cases {
+		ft := NewFieldType(cc.t)
+		ft.SetFlen(cc.flen)
+		ft.SetFlag(cc.flags)
+
+		TiDBStrictIntegerDisplayWidth = false
+		require.Equal(t, cc.e1, ft.CompactStr())
+
+		TiDBStrictIntegerDisplayWidth = true
+		require.Equal(t, cc.e2, ft.CompactStr())
+	}
+}