Remove mismatch between default value of struct field in C++ and other languages #1628
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This change is used to showcase the invalid behavior of the code generator. It implements new functional tests that verify the default values that are set in LIME file for nullable fields. The default value is invalid in the case of default constructed object in C++. There is a mismatch between C++ and Java/Swift/Dart. Signed-off-by: Patryk Wrobel <[email protected]>
This change introudces the same LIME structures
that the previous commit, but in smoke tests.
The following LIME syntax is used:
```
someField1: SomeImmutableStructWithDefaults? = {}
someField2: ImmutableStructWithCollections? = {}
```
It results in the following invalid C++ code (fields are nullopt):
```
some_field1
= std::optional<SomeImmutableStructWithDefaults>{};
some_field2
= std::optional<ImmutableStructWithCollections>{};
```
The generated C++ code for default values initializes fields
to nullopt instead of default-constructed structure. This
behavior is invalid and does not occur in other languages.
Signed-off-by: Patryk Wrobel <[email protected]>
This change ensures that fields, which use std::optional are initialized correctly, when default value is default-constructed struct. Usage of typename wrapped in std::optional was redundant and caused problems with initialized value and compilation. In this commit usage of std::optional prefix is removed when resolving default value. Signed-off-by: Patryk Wrobel <[email protected]>
Hsilgos
approved these changes
Nov 28, 2024
…value-in-cpp-and-other-languages
pwrobeldev
deleted the
pwrobeldev/mismatch-between-field-default-value-in-cpp-and-other-languages
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---------- Motivation ----------
This change fixes a bug related to invalid default value of nullable
field, which uses struct type. When field was nullable and its default
value was set to default-constructed structure, then the generated
code in C++ was invalid, because the field was initialized to std::nullopt
instead of default-constructed struct.
---------- Contents of the change ----------
This change:
invalid
CppNameResolver.ktto remove superflousstd::optionalprefix when resolving default value