Skip to content

[SPARK-23986][SQL] freshName can generate non-unique names #21080

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
mgaido91 wants to merge 3 commits into from
Closed

[SPARK-23986][SQL] freshName can generate non-unique names #21080

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
8623918
[SPARK-23986][SQL] freshName can generate non-unique names
mgaido91 Apr 16, 2018
58f72ae
fix a and a_1 conflict
mgaido91 Apr 17, 2018
0993827
review comments
mgaido91 Apr 17, 2018
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion ...lyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/codegen/CodeGenerator.scala
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -575,7 +575,7 @@ class CodegenContext {
if (freshNameIds.contains(fullName)) {

@cloud-fan cloud-fan Apr 17, 2018

Copy link
Copy Markdown
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

now we don't need this if

val id = freshNameIds.getOrElse(fullName, 0)
val res = s"${fullName}_$id"
freshNameIds(fullName) = id + 1
res

val id = freshNameIds(fullName)
freshNameIds(fullName) = id + 1
s"$fullName$id"
s"${fullName}_$id"
} else {
freshNameIds += fullName -> 1
fullName

@viirya viirya Apr 17, 2018

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

If the given name is something like name1_1, I think you can still produce non-unique variable name.

@viirya viirya Apr 17, 2018

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I'd suggest something like s"${fullName}_0" at L581. It also solves the failed tests.

@kiszk kiszk Apr 17, 2018

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

If I am correct, does this still have a conflict between a_01 wth a_0$id where $id = 1?

@viirya viirya Apr 17, 2018

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Isn't changed to s"${fullName}_$id"? So you will get a_0_1.

@cloud-fan cloud-fan Apr 17, 2018

Copy link
Copy Markdown
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I think it still has a problem. for sequence a_1, a, a, we have duplicated name a_1.

We can solve this problem by always adding the postfix.

@viirya viirya Apr 17, 2018

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Hmm, doesn't it be

a_1 -> a_1_0
a -> a_0
a -> a_1

?

@kiszk kiszk Apr 17, 2018 •
edited
Loading

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Ah, sorry for my misunderstanding. To change line 581 would work well with unlikely-used char.

@cloud-fan cloud-fan Apr 17, 2018

Copy link
Copy Markdown
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

@viirya my comment was for the current code without your change.

Expand Down
7 changes: 7 additions & 0 deletions ...talyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/CodeGenerationSuite.scala
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -489,4 +489,11 @@ class CodeGenerationSuite extends SparkFunSuite with ExpressionEvalHelper {
assert(!ctx.subExprEliminationExprs.contains(ref))
}
}

test("SPARK-23986: freshName can generate duplicated names") {
val ctx = new CodegenContext
val names = ctx.freshName("myName1") :: ctx.freshName("myName1") ::
ctx.freshName("myName11") :: Nil
assert(names.distinct.length == 3)
}
}