Files
flatbuffers-bigfoot/tests/MyGame/Example/NestedStruct.py
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

155 lines
4.8 KiB
Python

# automatically generated by the FlatBuffers compiler, do not modify
# namespace: Example
import flatbuffers
from flatbuffers.compat import import_numpy
np = import_numpy()
class NestedStruct(object):
__slots__ = ['_tab']
@classmethod
def SizeOf(cls):
return 32
# NestedStruct
def Init(self, buf, pos):
self._tab = flatbuffers.table.Table(buf, pos)
# NestedStruct
def A(self, j = None):
if j is None:
return [self._tab.Get(flatbuffers.number_types.Int32Flags, self._tab.Pos + flatbuffers.number_types.UOffsetTFlags.py_type(0 + i * 4)) for i in range(self.ALength())]
elif j >= 0 and j < self.ALength():
return self._tab.Get(flatbuffers.number_types.Int32Flags, self._tab.Pos + flatbuffers.number_types.UOffsetTFlags.py_type(0 + j * 4))
else:
return None
# NestedStruct
def AAsNumpy(self):
return self._tab.GetArrayAsNumpy(flatbuffers.number_types.Int32Flags, self._tab.Pos + 0, self.ALength())
# NestedStruct
def ALength(self):
return 2
# NestedStruct
def AIsNone(self):
return False
# NestedStruct
def B(self): return self._tab.Get(flatbuffers.number_types.Int8Flags, self._tab.Pos + flatbuffers.number_types.UOffsetTFlags.py_type(8))
# NestedStruct
def C(self, j = None):
if j is None:
return [self._tab.Get(flatbuffers.number_types.Int8Flags, self._tab.Pos + flatbuffers.number_types.UOffsetTFlags.py_type(9 + i * 1)) for i in range(self.CLength())]
elif j >= 0 and j < self.CLength():
return self._tab.Get(flatbuffers.number_types.Int8Flags, self._tab.Pos + flatbuffers.number_types.UOffsetTFlags.py_type(9 + j * 1))
else:
return None
# NestedStruct
def CAsNumpy(self):
return self._tab.GetArrayAsNumpy(flatbuffers.number_types.Int8Flags, self._tab.Pos + 9, self.CLength())
# NestedStruct
def CLength(self):
return 2
# NestedStruct
def CIsNone(self):
return False
# NestedStruct
def D(self, j = None):
if j is None:
return [self._tab.Get(flatbuffers.number_types.Int64Flags, self._tab.Pos + flatbuffers.number_types.UOffsetTFlags.py_type(16 + i * 8)) for i in range(self.DLength())]
elif j >= 0 and j < self.DLength():
return self._tab.Get(flatbuffers.number_types.Int64Flags, self._tab.Pos + flatbuffers.number_types.UOffsetTFlags.py_type(16 + j * 8))
else:
return None
# NestedStruct
def DAsNumpy(self):
return self._tab.GetArrayAsNumpy(flatbuffers.number_types.Int64Flags, self._tab.Pos + 16, self.DLength())
# NestedStruct
def DLength(self):
return 2
# NestedStruct
def DIsNone(self):
return False
def CreateNestedStruct(builder, a, b, c, d):
builder.Prep(8, 32)
for _idx0 in range(2 , 0, -1):
builder.PrependInt64(d[_idx0-1])
builder.Pad(5)
for _idx0 in range(2 , 0, -1):
builder.PrependInt8(c[_idx0-1])
builder.PrependInt8(b)
for _idx0 in range(2 , 0, -1):
builder.PrependInt32(a[_idx0-1])
return builder.Offset()
try:
from typing import List
except:
pass
class NestedStructT(object):
# NestedStructT
def __init__(self):
self.a = None # type: List[int]
self.b = 0 # type: int
self.c = None # type: List[int]
self.d = None # type: List[int]
@classmethod
def InitFromBuf(cls, buf, pos):
n = flatbuffers.encode.Get(flatbuffers.packer.uoffset, buf, 0)
nestedStruct = NestedStruct()
nestedStruct.Init(buf, pos+n)
return cls.InitFromObj(nestedStruct)
@classmethod
def InitFromObj(cls, nestedStruct):
x = NestedStructT()
x._UnPack(nestedStruct)
return x
# NestedStructT
def _UnPack(self, nestedStruct):
if nestedStruct is None:
return
if not nestedStruct.AIsNone():
if np is None:
self.a = []
for i in range(nestedStruct.ALength()):
self.a.append(nestedStruct.A(i))
else:
self.a = nestedStruct.AAsNumpy()
self.b = nestedStruct.B()
if not nestedStruct.CIsNone():
if np is None:
self.c = []
for i in range(nestedStruct.CLength()):
self.c.append(nestedStruct.C(i))
else:
self.c = nestedStruct.CAsNumpy()
if not nestedStruct.DIsNone():
if np is None:
self.d = []
for i in range(nestedStruct.DLength()):
self.d.append(nestedStruct.D(i))
else:
self.d = nestedStruct.DAsNumpy()
# NestedStructT
def Pack(self, builder):
return CreateNestedStruct(builder, self.a, self.b, self.c, self.d)