added tests to verify no false positives rename-column found

go/logic/migrator.go

@@ -229,7 +229,7 @@ func (this *Migrator) validateStatement() (err error) {
 	if this.parser.HasNonTrivialRenames() && !this.migrationContext.SkipRenamedColumns {
 		this.migrationContext.ColumnRenameMap = this.parser.GetNonTrivialRenames()
 		if !this.migrationContext.ApproveRenamedColumns {
-			return fmt.Errorf("gh-ost believes the ALTER statement renames columns, as follows: %v; as precation, you are asked to confirm gh-ost is correct, and provide with `--approve-renamed-columns`, and we're all happy. Or you can skip renamed columns via `--skip-renamed-columns`, in which case column data may be lost", this.parser.GetNonTrivialRenames())
+			return fmt.Errorf("gh-ost believes the ALTER statement renames columns, as follows: %v; as precaution, you are asked to confirm gh-ost is correct, and provide with `--approve-renamed-columns`, and we're all happy. Or you can skip renamed columns via `--skip-renamed-columns`, in which case column data may be lost", this.parser.GetNonTrivialRenames())
 		}
 		log.Infof("Alter statement has column(s) renamed. gh-ost finds the following renames: %v; --approve-renamed-columns is given and so migration proceeds.", this.parser.GetNonTrivialRenames())
 	}

localtests/rename-none-column/create.sql

@@ -0,0 +1,8 @@
+drop table if exists gh_ost_test;
+create table gh_ost_test (
+  id int auto_increment,
+  c1 int not null,
+  primary key (id)
+) auto_increment=1;
+
+drop event if exists gh_ost_test;

localtests/rename-none-column/extra_args

@@ -0,0 +1 @@
+--alter="add column exchange double comment 'exchange rate used for pay in your own currency'"

localtests/rename-none-comment/create.sql

@@ -0,0 +1,8 @@
+drop table if exists gh_ost_test;
+create table gh_ost_test (
+  id int auto_increment,
+  c1 int not null,
+  primary key (id)
+) auto_increment=1;
+
+drop event if exists gh_ost_test;

localtests/rename-none-comment/extra_args

@@ -0,0 +1 @@
+--alter="add column exchange_rate double comment 'change rate used for pay in your own currency'"