sql/mysql: support validating mysql collation/charset

internal/integration/testdata/sqlite/cli-atlasci-sanity.txt

@@ -6,11 +6,15 @@ cmp got2.txt expected2.txt
 
 -- migrations/1.sql --
 CREATE TABLE users (id int);
+
 CREATE TABLE pets (id int);
+
 -- migrations/2.sql --
 DROP TABLE users;
+
 -- migrations/3.sql --
 DROP TABLE pets;
+
 -- expected1.txt --
 Destructive changes detected in file 3.sql:
 

sql/internal/sqlx/diff.go

@@ -64,7 +64,7 @@ type (
 	// If the DiffDriver implements the Normalizer interface, TableDiff normalizes its table
 	// inputs before starting the diff process.
 	Normalizer interface {
-		Normalize(from, to *schema.Table)
+		Normalize(from, to *schema.Table) error
 	}
 )
 
@@ -148,7 +148,9 @@ func (d *Diff) TableDiff(from, to *schema.Table) ([]schema.Change, error) {
 	}
 	// Normalizing tables before starting the diff process.
 	if n, ok := d.DiffDriver.(Normalizer); ok {
-		n.Normalize(from, to)
+		if err := n.Normalize(from, to); err != nil {
+			return nil, err
+		}
 	}
 	var changes []schema.Change
 	if from.Name != to.Name {