tree efd762095e16ee45c023526163918b7a26d6e1fa
parent 0862f69f7be874875611b71447cc9907fb8cf9db
author Josh Rosen <joshrosen@databricks.com> 1715051336 -0700
committer Dongjoon Hyun <dhyun@apple.com> 1715051336 -0700

[SPARK-48150][SQL] try_parse_json output should be declared as nullable

### What changes were proposed in this pull request?

The `try_parse_json` expression added in https://github.com/apache/spark/pull/46141 declares improper output nullability: the `try_` version's output must be marked as nullable. This PR corrects the nullability and adds a test.

### Why are the changes needed?

Incorrectly declaring an expression's output as non-nullable when it is actually nullable may lead to crashes.

### Does this PR introduce _any_ user-facing change?

Yes, it affects output nullability and thus may affect query result schemas.

### How was this patch tested?

New unit test cases.

### Was this patch authored or co-authored using generative AI tooling?

No.

Closes #46409 from JoshRosen/fix-try-parse-json-nullability.

Authored-by: Josh Rosen <joshrosen@databricks.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>