[Variant] If ObjectBuilder::finalize is not called, the resulting Variant object is malformed. #7863
Description
Describe the bug
If ObjectBuilder::finalize is not called, the resulting Variant object is malformed.
To Reproduce
Here is an example that would work with finalize on drop, but not with this PR as is
#[test]
fn test_object_list_no_finish() {
let mut builder = VariantBuilder::new();
let mut list_builder = builder.new_list();
{
let mut object_builder = list_builder.new_object();
object_builder.insert("id", 1);
object_builder.finish().unwrap();
}
{
let mut object_builder = list_builder.new_object();
object_builder.insert("id", 2);
// NOTE object_builder.finish() is not called here
}
list_builder.finish();
let (metadata, value) = builder.finish();
let variant = Variant::try_new(&metadata, &value).unwrap();
let list = variant.as_list().unwrap();
}If object_builder.finish() is not called, then this line fails:
let list = variant.as_list().unwrap();The error is like this (which is pretty unintuitive to me):
called `Result::unwrap()` on an `Err` value: InvalidArgumentError("Received empty bytes")
thread 'builder::tests::test_object_list_no_finish' panicked at parquet-variant/src/builder.rs:1154:59:
called `Result::unwrap()` on an `Err` value: InvalidArgumentError("Received empty bytes")
stack backtrace:
0: __rustc::rust_begin_unwind
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panicking.rs:697:5
1: core::panicking::panic_fmt
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/panicking.rs:75:14
2: core::result::unwrap_failed
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/result.rs:1732:5
3: core::result::Result<T,E>::unwrap
at /Users/andrewlamb/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/src/rust/library/core/src/result.rs:1137:23
4: parquet_variant::builder::tests::test_object_list_no_finish
at ./src/builder.rs:1154:23
5: parquet_variant::builder::tests::test_object_list_no_finish::{{closure}}
at ./src/builder.rs:1133:36
6: core::ops::function::FnOnce::call_once
at /Users/andrewlamb/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/src/rust/library/core/src/ops/function.rs:250:5
7: core::ops::function::FnOnce::call_once
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/ops/function.rs:250:5
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
**Expected behavior**
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**Additional context**
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