HSQLDB: Unable to parse `DROP INDEX IF EXISTS` statement

[nlochschmidt]

Which version and edition of Flyway are you using?

6.0.7

Which client are you using? (Command-line, Java API, Maven plugin, Gradle plugin)

Spring Boot integration

Which database are you using (type & version)?

HSQLDB 2.5.0

Which operating system are you using?

macOS 10.14.6

What did you do?

Wrote a migration with a simple conditional DROP INDEX statement:

DROP INDEX IF EXISTS blog_post__name_idx;

What did you expect to see?

Successful migration and a dropped index.

What did you see instead?

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'flywayInitializer' defined in class path resource [org/springframework/boot/autoconfigure/flyway/FlywayAutoConfiguration$FlywayConfiguration.class]: Invocation of init method failed; nested exception is org.flywaydb.core.api.FlywayException: Unable to parse statement in db/migration/common/V2__drop_blog_post_name_idx.sql at line 1 col 1: Incomplete statement at line 1 col 1: DROP INDEX IF EXISTS blog_post__name_idx;

Also when I debug into the HSQLDBParser in line 77 I can see that the INDEX token has the type IDENTIFIER which seams wrong and it is therefore looking for the token DROP in CONDITIONALLY_CREATABLE_OBJECTS which it won't find. It is then increasing the blockDepth and failing later because of that.

This might be related to #2442

[juliahayward]

It's not the same as #2442 but it's definitely failing to spot INDEX as a keyword that can appear in the form DROP <THING> IF EXISTS. I have a fix which should go in 6.0.8.