[SPARK-40136][SQL] Fix the fragment of SQL query contexts

[MaxGekk]

What changes were proposed in this pull request?

In the PR, I propose to change implementation of fragment in SQLQueryContext to get the fragment correctly. Before the changes, fragment misses the last char because originStopIndex.get points to the last char of fragments but substring() gets a sub-string up to endIndex - 1.

Why are the changes needed?

It fixes a bug.

Does this PR introduce any user-facing change?

Yes.

How was this patch tested?

By running new test suite:

$ build/sbt "test:testOnly *SQLQueryContextSuite"
$ build/sbt "test:testOnly *TreeNodeSuite"
$ build/sbt "test:testOnly *QueryExecutionAnsiErrorsSuite"

[MaxGekk]

@cloud-fan@HyukjinKwon Could you review this bug fix, please.

[cloud-fan]

this basically tests String.substring... can we have an end-to-end test?

[MaxGekk]

@cloud-fan The failed test DIVIDE_BY_ZERO: can't divide an integer by zero *** FAILED *** is an end-to-end test actually. Let me fix it.

[cloud-fan]

Great! Can we remove this test suite then? The code we are testing is simply sqlText.get.substring(originStartIndex.get, originStopIndex.get + 1)

[MaxGekk]

I wouldn't remove this unit tests because:

1. Current implementation of fragment is not only substring(). It is a combination of isValid + substring.
2. The end-to-end tests don't check corner cases.

SQLQueryContext has poor test coverage currently. Instead of to hope that end-to-end tests guarantee its correctness, I would add more simple unit tests to SQLQueryContext.

[MaxGekk]

The failure of ImageFileFormatSuite is not related to the PR, I believe. @cloud-fan Could you take a look at this PR one more time, please.

[dongjoon-hyun]

+1, LGTM.

[MaxGekk]

Merging to master. Thank you, @cloud-fan@dongjoon-hyun for review.