Commit Graph

50 Commits

Author SHA1 Message Date
RCRalph
8d2c333b36 fix: Added return value to non type-prefixed create vector function (#8945)
* fix: Added return value to non type-prefixed create vector function

* chore: Added generated code
2026-03-05 02:09:09 +00:00
Jacob Abrams
af8997b567 [Python] Improve python API (#8781)
* Fix generate_code script path

* [Python] Make StartVector public

Make StartVector vector public since it is already being used in
generated code

* [Python] Improve vector creation for Python API

Makes Python API for vectors cleaner like Rust and Swift

---------

Co-authored-by: Derek Bailey <derekbailey@google.com>
2026-01-21 01:01:20 +00:00
Łukasz Kurowski
c526cb640b [Python] Enhance object API __init__ with typed keyword arguments (#8615)
This commit significantly improves the developer experience for the Python Object-Based API by overhauling the generated `__init__` method for `T`-suffixed classes.

Previously, `T` objects had to be instantiated with an empty constructor, and their fields had to be populated manually one by one. This was verbose and not idiomatic Python.

This change modifies the Python code generator (`GenInitialize`) to produce `__init__` methods that are:

1.  **Keyword-Argument-Friendly**: The constructor now accepts all table/struct fields as keyword arguments, allowing for concise, single-line object creation.

2.  **Fully Typed**: The signature of the `__init__` method is now annotated with Python type hints. This provides immediate benefits for static analysis tools (like Mypy) and IDEs, enabling better autocompletion and type checking.

3.  **Correctly Optional**: The generator now correctly wraps types in `Optional[...]` if their default value is `None`. This applies to strings, vectors, and other nullable fields, ensuring strict type safety.

The new approach remains **fully backward-compatible**, as all arguments have default values. Existing code that uses the empty constructor will continue to work without modification.

#### Example of a Generated `__init__`

**Before:**

```python
class KeyValueT(object):
    def __init__(self):
        self.key = None  # type: str
        self.value = None  # type: str
```

**After:**

```python
class KeyValueT(object):
    def __init__(self, key: Optional[str] = None, value: Optional[str] = None):
        self.key = key
        self.value = value
```

#### Example of User Code

**Before:**

```python
# Old, verbose way
kv = KeyValueT()
kv.key = "instrument"
kv.value = "EUR/USD"
```

**After:**

```python
# New, Pythonic way
kv = KeyValueT(key="instrument", value="EUR/USD")
```
2025-07-22 23:57:39 -07:00
Felix
c15fe421ba Use correct default type for str (#8623)
* [Python] Use correct type for str with None

Otherwise mypy will correctly flag code like this

def __init__(self):
  self.fooBar = None  # type: Optional[str]

error: Incompatible types in assignment (expression has type "None", variable has type "str")

* [Python] Make list type optional as they can contain None
2025-07-04 23:47:36 +00:00
Aaron Barany
5ba80c24e0 Fix python type annotation output when not enabled (#7983)
Fixes #7971

Co-authored-by: Derek Bailey <derekbailey@google.com>
2023-11-29 09:58:21 -08:00
Chih-Hsuan Yen
a352bdbc34 Fix python tests (#7960)
* Don't generate types unless --python-typing specified

Fixes https://github.com/google/flatbuffers/issues/7944

* Fix incorrect import statements

Fixes https://github.com/google/flatbuffers/issues/7951

* Fix $PYTHONPATH in PythonTest.sh

Regressed from https://github.com/google/flatbuffers/pull/7529

* PythonTest: fail if something goes wrong

GitHub Actions runs `bash PythonTest.sh`, and thus failures were not
visible.

* Build flatc for Python tests

* Regenerate codes

---------

Co-authored-by: Derek Bailey <derekbailey@google.com>
2023-05-17 13:10:51 -07:00
Max Burke
a397dd7e8c Optionally generate Python type annotations (#7858)
* optionally generate type prefixes and suffixes for python code

* fix codegen error when qualified name is empty

* WIP: Python typing

* more progress towards python typing

* Further iterate on Python generated code typing

* clang-format

* Regenerate code

* add documentation for Python type annotations option

* generate code with Python type annotations

* handle forward references

* clang-format
2023-04-28 09:38:29 -07:00
Max Burke
56ecc1f548 Optionally generate type prefixes and suffixes for python code (#7857)
* optionally generate type prefixes and suffixes for python code

* fix codegen error when qualified name is empty

* generated code updated
2023-04-25 21:38:16 -07:00
James Kuszmaul
8aa8b9139e Fix handling of +/-inf defaults in TS/rust/go/dart codegen (#7588)
+/-inf were not being handled, and so invalid typescript was being
generated when a float/double had an infinite default value. NaN was
being handled correctly.

Co-authored-by: Derek Bailey <derekbailey@google.com>
Co-authored-by: Casper <casperneo@uchicago.edu>
2022-11-08 10:59:46 -08:00
Joshua Smith
043a24f2e4 [Python] Fixed the issue with nested unions relying on InitFromBuf. (#7576)
* feat: Fixed the issue with nested unions relying on InitFromBuf.
Problem: Issue #7569
Nested Unions were broken with the introduction of parsing buffers with an initial encoding offset.

Fix:
Revert the InitFromBuf method to the previous version and introduction of InitFromPackedBuf that allows
users to read types from packed buffers applying the offset automatically.

Test:
Added in TestNestedUnionTables to test the encoding and decoding ability using a nested table with a
union field.

* fix: Uncommented generate code command
2022-10-26 14:56:52 -07:00
Joshua Smith
413115858c [Python] Python fixed size array (#7529)
* feat: Added support for fixed sized arrays to python

Problem:
We encountered that using fixed arrays from C++ to python that python would
not read those arrays correctly due to no size information being encoded in the byte
array itself.

Fix:
Encode the sizes within the generated python file during code generation.
Specfically we add GetArrayAsNumpy to the python version of table, which takes as input
the length of the vector. When generating the python message files we include this length
from the VectorType().fixed_length.

* fix: added digit support for camel case to snake case conversion

Problem:
When including a number in the message name we would encounter cases where SnakeCase would
not add the appropirate breaks. e.g. Int32Stamped -> int_32stamped rather than int_32_stamped.

Fix:
To fix this we can add the condition that we check if the current character is not lower and
not a digit, that we check if the previous character was a lower or digit. If it was a lower
or digit then we add the break.

* fix: Array support for structures

Problem:
The python generated code for handling non-struct and struct vectors
and arrays was inconsistent. The calls to populate the obj api was
creating incorrect code.

Solution:
To fix this the VectorOfStruct and VectorOfNonStruct was rewritten
to handle array cases and bring the two methods in line which each
other.

Testing:
PythonTesting.sh now correctly runs and generates the code for
array_test.fbs.
Minor modifications were done on the test to use the new index
accessor for struct arrays and the script correctly sources the
location of the python code.

* chore: clang format changes

* Added code generated by scripts/generate_code. Modified GetArrayOfNonStruct slightly
to allow for function overloading allowing the user to get a single element of an array
or the whole array.

* Added new_line parameter to OffsetPrefix to allow optional new lines to be added.
This allows us to use the GenIndents method that automatically adds new lines instead.

* Reupload of generated code from the scripts/generate_code.py

* Removed new line in GetVectorAsNumpy.

* Updated Array lengths to use Length methods where possible. Added fallthrough for GenTypePointer. Added digit check to CamelToSnake method. Added and modified tests for ToSnakeCase and CamelToSnake.

* Added range check on the getter methods for vector and array types. Renamed == as is for python
2022-09-22 11:08:09 -07:00
James Kuszmaul
9ed1323044 Fix 64-bit numeric enum values in typescript (#7135)
* Fix 64-bit default numeric enum values in typescript

If you had a default value that wasn't a valid enum value (e.g., a zero
if you used a bit_flag setting, like you get with AdvancedFeatures
in reflection.fbs), we weren't using BigInt.

* Run generate_code.py

* [DART] Handle deprecated fields & invalid enum defaults

* Update .NET test
2022-03-04 21:57:48 -08:00
Derek Bailey
39c8a19ce2 fixed comparator for native_inline (#7076)
* fixed comparator for native_inline

* added native_inline data

* updated more tests for the new field

* more fixes
2022-02-02 23:44:43 -08:00
lu-wang-g
fd4ff23da0 Keep methods with struct name and switch them to default (#6879)
* Keep methods with struct name and switch them to default

This PR can help fix the following two issues:
1): A set of simplified API (without struct name) was added in
https://github.com/google/flatbuffers/pull/6336. It causes name
conflict when merging all generated python file into a single one
(the primary usage senario in Google).
2): Flatbuffers 2.0 generates absolute import path, which may cause
name space conflicts. See more details in
https://github.com/google/flatbuffers/issues/5840.

The solution for both is to generate the merged Python code, similar
C++. The merged code will not contain the simplied API, but only the
method with struct name. For issue (1), it will mimic the exactly
usage pattern for Google internal. For issue (2), users can generate
the merged flatbuffer code, without worrying about the imports.

The above idea will be implemented in the following steps:
Step 1 (this PR): revert changes in https://github.com/google/flatbuffers/pull/6336
that set the simplified API as default. Remove statements that the
original API will be deprecated, and reset the original API as default.
Step 2 (the following PR): create a flag to generate the merged code.
The Simplified API will be removed from the merged code, otherwise it
will cause name conflict.

* Update the generated sample code

* Update the generated example code

* Reverst the changes of GetRootAs

* Update examples from grpc/example/generate.sh
2021-11-04 15:12:25 -07:00
Richard A Hofer
13d9e35858 Better python generated code naming (#6336)
* Remove a lot of redundancy from the Python generated code.

Update tutorial to reflect new Python generated code.

* Add aliases for newly deprecated Python generated methods.

This should help with backwards compatibility.

* Fix incorrect names in deprecated comments.
2021-01-28 12:35:37 -08:00
Vladimir Glavnyy
83ce29cc22 [C++, JSON] Fix nullptr access when reading a key with a default value. (#6375)
This commit fixes handling of default and NULL `key` fields in `Parser::ParseVector` (#5928).

The JSON generator updated. It outputs `key` fields even if the `--force-defaults` option is inactive.

Additional test cases for `key` added.
2021-01-07 11:24:59 -08:00
Richard A Hofer
4363c1d2cb Fix generated EndVector. (#6385) 2021-01-05 14:45:23 -08:00
Richard A Hofer
24dd85fd28 Generate code to encode and decode nested flatbuffers in Python. (#6354)
* Generate code to encode and decode nested flatbuffers in Python.

* Delete accidental trailing whitespace.

* Fully delete trailing whitespace.
2021-01-04 12:18:19 -08:00
Richard A Hofer
f8b203c9c4 Add vectorNumElements attribute to Builder for simpler vector creation. (#6328)
* Add vectorNumElements attribute to Builder for simpler vector creation.

This adds a default to EndVector which should simplify its use.

* Update tutorial to reflect new default arg in Python EndVector.

* Remove optional argument to Python EndVector.

* Add generated files.

* Unset Builder.vectorNumElems when not in use.
2020-12-14 12:00:28 -08:00
David P. Sicilia
a9e91116d2 [Python] Commit some orphan python genfile diffs. (#6325) 2020-12-10 16:43:40 -08:00
Casper
46a8c7e958 Added required-nested-flatbuffer to monster_test and fixed rust (#6236)
Co-authored-by: Casper Neo <cneo@google.com>
2020-11-05 13:58:06 -08:00
Marc Butler
0e3fdd0eea Escape characters in jsonschema descriptions (#5644)
* Escape JSON Schema comments

* Add quotes to monster comment

Thus exercising the JSON Schema comment escape support.
2020-03-12 12:10:30 -07:00
lu-wang-g
a2c12900aa Optimize Pack method using numpy (#5662)
Add the support to pack using numpy for scalar vectors when numpy is available.
2019-12-26 21:42:11 -05:00
lu-wang-g
65f8703572 Flatbuffers Python Object API (#5616)
* Flatbuffers Python Object API

Implement the logic to generate the Python object API that can
unpack the data from a buf class into an object class, and pack
the data of an object class to a buf class.

* Fix the build issues

Remove unused parameters and replace auto in the for-loop statement
with std::string to make it compatible with VS2010.

* Fix the build issues.

* Add support for Array type

Added logic to handle Array type in Python Object API. Updated the
generated code accordingly.

* Fix the old style casting from int to char

* Fixed another conversion from int to char

* Fixed the import for typing

Importing typing may cause errors when a machine do not have the
moduel typing installed. This PR fixes the issue by guarding
"import typing" with the "try/except" statement.

* Fix issue of iterating the vector of import list

* Update the generated examples using generate_code.sh

* Fix the import order for typing

The import list was stored in unordered_set, so that each generated
codes may have different import order. Therefore, it failed in the
consistency test where two generated copies need to have exactly the
same apperance.

* Optimize unpack using numpy

Use numpy to unpack vector whenever it is possible to improve unpack
performance.

Also, added codegen command for Python specificly in generate_code.sh,
because --no-includes cannot be turn on for Python.

* Fix the import order

* Update generate_code.bat for windows accordingly

* Replace error message with pass

Avoid printing error message for every Python2 users about typing.
Replace it with pass.
2019-12-02 14:11:28 -08:00
Jaemin Park
4b870aca98 [Javascript] Fix syntax error for signed enum (#5503)
* wrap quotes to enum name map to prevent syntax errorn when enum value is negative

* Add a test that covers signed enum case
2019-09-05 10:22:04 -07:00
Joseph Pyott
9fa8245e81 Python: Added support for file_identifiers (#5123)
* Python: Added support for file_identifiers

* Added tests. Fixed file_identifier code.

* Python: Fixed excessive padding of file_identifier. Repaired tests.

* Python: Made code compatible with python2.7

* Python: Typo fix in @endcond

* whitespace normaalization

* Stylistic change from if(not X is None) to if(X is not None). Added comment to type string.

* Python: Added support for automatic code generation of file_identifiers. Added tests for said code generation.

* converted sprintf to snprintf

* Bugfix, added snprint deffinition for MSVC

* changed snprint deffinition for MSVC to sprint_s

* changed scanf to IntToStringHex. Renamed HasFileIdentifier to GenHasFileIdentifier.

* Added updated genereated code to commit

* Python bugix: flatc no longer produces HasFileIdentfier for shcemas with no file identifier

* Added tests to verify `MonsterBufferHasIdentifier` returns false on no Identifier

* Python: added tests for GetBufferIdentifier and BufferHasIdentifier
Python: removed unessasary parenethesis in if statements
Minor format changes.

* Python : correceted instances of keyword arguments being called as positional arguments

* fixed typos and grammer in comments

* Minor style fixes

* Indentation fix

* Equals style changes

* Python: Fixed Alignment Issues. Changed test code to test against atual output

* Ran make(forgot to run make last commit)

* Python: Style changes

* Style changes

* indentation and style

* readded CONTRIBUTING.md

* Formatting tweak

Mostly to make CI run again

* More formatting fixes

* More formatting fixes

* More formatting fixes

* More formatting fixes

* Formatting fix

* More formatting fixes

* Formatting

* ran generate_code.sh
2019-07-26 11:06:25 -07:00
Vladimir Glavnyy
95004218f7 Fix multi-line comments for cpp enums (#5345) (#5346)
- fix CSharp comments generation
- fix Python comments generation
- fix Lua comments generation
- fix PHP comments generation
- fix Dart comments generation
- add brief description of Color enum
- add multi-line comments to the Monster:Color
2019-06-02 12:36:49 -07:00
Vladimir Glavnyy
f9ebfcb9c4 Make Monster's Color unsigned (#5318)
- update C++ monster_test::Color to unsigned type
- update Go Color:ubyte in the go_test.go
- add workaround for unsigned enum in java test
- sync generate.bat and generate.sh
2019-05-09 10:07:38 -07:00
Wouter van Oortmerssen
980a6d66d3 Fixed vectors of enums in object API serialized incorrectly.
And also added tests for them.

Change-Id: I91af1904105435601287291412e82d5066f476a5
Tested: on Linux.
2018-11-05 14:33:36 -08:00
Frank Benkstein
91fe9ba93f make unions with type aliases more usable (#5019)
Some generic C++ and Rust code is not generated when unions use type
aliases because of potential ambiguity. Actually check for this
ambiguity and only disable offending code only if it is found.
2018-11-01 12:51:25 -07:00
Tin Tvrtković
a9640bd9e1 [BREAKING CHANGE] Python: handle bool table fields properly. (#4736)
* Python: handle bool table fields properly.

* Small refactor.

* Use snake_case instead of camelCase. Use auto.
2018-05-14 13:30:10 -07:00
Tin Tvrtković
b10123ff63 Python: return None for missing strings. (#4733)
[BREAKING CHANGE] Python: return None for missing strings.
2018-05-10 10:34:20 -07:00
Christian Helmich
9ce98dd77d Support attribute "cpp_ptr_type" on table elements marked as "hash" (#4643)
* added intended use-cases to monster_test.fbs

* added check for `cpp_ptr_type` on hashed fields
added default value 'naked' to `cpp_ptr_type` on hashed fields

* added C++ generation of cpp_type vectors
removed ctor call for vector fields
added condition !vector for cpp_type check
added Pack() and UnPack() code generation for vector of hashes
added generation of correct resolve/rehash for cpp_type elements

* added attribute 'cpp_ptr_type_get' to hold accessor for pointer types possible where '.get()' does not work
use case: cpp_ptr_type:"std::weak_ptr", cpp_ptr_type_get:".lock().get()"

* run flatc to re-generate headers

* added bool param is_ctor to GetDefaultScalarValue() to differentiate between usage places

* modified monster_test.fbs to remove usage of shared_ptr/weak_ptr
reason: STLport does not support std::shared_ptr and std::weak_ptr

* run flatc again to re-generate headers

* fixed symbol unique_ptr not in namespace std when building with STLport
2018-03-05 08:40:55 -08:00
Christian Helmich
59e26017cb added support for parsing hash on vector elements (#4502)
* added support for parsing hash on vector elements

reversed check for scalar to check for vector

added C++ generation of cpp_type vectors

removed ctor call for vector fields
added condition !vector for cpp_type check

added Pack() and UnPack() code generation for vector of hashes

* schema change:
added table Referrable and weak references towards it from Monster

added single_weak_reference to Monster table
changed order with vector_of_weak_references

* re-generated monster schema dependent code

added Referrable.cs to FlatBuffers.Test.csproj
2018-02-22 11:04:26 -08:00
Dariusz Ostolski
5e4739184f Fix issue #4389, if field is ommitted the return type is the same for… (#4444)
* Fix issue #4389, if field is ommitted the return type is the same for python generator

* Fix issue #4389, bytes is returned when field is omitted

* Fix issue #4389, added generated python code after generator modification
2017-10-05 14:07:42 -07:00
Wouter van Oortmerssen
321a1c9dc0 Cleaned up namespace handling.
A Namespace object is now guaranteed unique.
This cleaned up some old workarounds and latent bugs.

Change-Id: Ic3f12d89947871b03b2c449ba51b3186f953adde
Tested: on Linux.
Bug: 21336857
2017-08-24 13:39:45 -07:00
Kevin Rose
3282a84e30 [Python] (scalar) vector reading speedup via numpy (#4390)
* Add numpy accessor to python flatbuffers scalar vectors

* Update python tests to test numpy vector accessor

* Update appveyor CI to run Python tests, save generated code as artifact

* Update example generated python code

* Add numpy info to python usage docs

* Update test schema and python tests w/ multi-byte vector

* did not mean to push profiling code

* adding float64 numpy tests
2017-08-01 08:34:00 -07:00
Stewart Miles
f064a6cc60 Test case for CreateVectorOfStructs() using a callback.
Fixes issue #4392, also fixed C++98 compatible code generation in tests.

Change-Id: Ia5833026e615ad19d24a0439bdba2e3b45c5f86c
2017-07-24 14:19:49 -07:00
Wouter van Oortmerssen
dddd0865cb Added nested FlexBuffer parsing
Change-Id: I918b66eb5646d035e3aae675f745802eb54b03ea
2017-06-12 14:34:45 -07:00
tianyapiaozi
a5cc2092a6 Support binary search for struct in cpp (#4245)
* Support binary search for struct in cpp

CreateVectorOfSortedStruct is provided for convenience.

* fix continuous-integration error

* add generated files

* compile Ability.cs in csharp test

* compile Ability.cs in csharp

* modify according to code review
2017-03-29 09:51:12 -07:00
Robert
a56c6e5195 Merge pull request #363 from danring/fix-341
Emit GetRootAs methods for all types in Go and Python
2016-07-22 15:12:35 -07:00
Wouter van Oortmerssen
afa276288c Added additional convenience overloads to CreateVector().
Bug: 29337887, 29336299
Change-Id: Iad8b3b2263f6cea7ee7e45994369194960df293b
Tested: on Linux.
2016-06-15 14:31:34 -07:00
Dan Ring
1f8e3c13e6 Emit GetRootAs methods for all types in Go and Python 2016-06-14 18:41:33 -04:00
lakedaemon
cd1493b082 sharing the Flatbuffers warning 2016-05-26 15:26:58 +02:00
Wouter van Oortmerssen
fd542c71e3 Fixed float suffix not being added on implicit float defaults.
Change-Id: I8dcbb5e93836356511d411ef86452babd3dd3c0b
Tested: on Linux.
2016-04-20 12:06:32 -07:00
Wouter van Oortmerssen
4d7890c2c9 Fixed whole-number float default values missing a .0 suffix.
A previous commit that added "f" for C++/Java/C# would break
on gcc of constants like 3f, which are now output as 3.0f

Tested: on Linux

Change-Id: If9cabbe3c6d6948a5050b8b123bda9c06e181f52
2016-04-18 11:50:46 -07:00
Wouter van Oortmerssen
29d957ed5e Fixed missing "f" on float default values in C++/Java/C#
Bug: 28145201
Change-Id: I5a1818c40c2f4fbd00cfec3362040407976f7a39
Tested: on Linux.
2016-04-13 17:29:03 -07:00
Wouter van Oortmerssen
4d7810424c Allow structs to be parsed in JSON with out of order fields.
Also simplified the code and made it faster.

Change-Id: I1d83b1165a4a9a4380d1bfb5538769c012d2d367
Tested: on Linux.
2015-10-28 17:54:11 -07:00
Maxim Zaks
ac10873e26 fixed code generator for array of bools
Change-Id: I3cdd801b641bf180222203a37634598350d340e3
2015-08-19 14:39:06 -07:00
rw
48dfc69ee6 Port FlatBuffers to Python.
Implement code generation and self-contained runtime library for Python.

The test suite verifies:
  - Correctness of generated Python code by comparing output to that of
    the other language ports.
  - The exact bytes in the Builder buffer during many scenarios.
  - Vtable deduplication correctness.
  - Edge cases for table construction, via a fuzzer derived from the Go
    implementation.
  - All code is simultaneously valid in Python 2.6, 2.7, and 3.4.

The test suite includes benchmarks for:
  - Building 'gold' data.
  - Parsing 'gold' data.
  - Deduplicating vtables.

All tests pass on this author's system for the following Python
implementations:
  - CPython 2.6.7
  - CPython 2.7.8
  - CPython 3.4.2
  - PyPy 2.5.0 (CPython 2.7.8 compatible)
2015-05-12 15:40:29 -07:00