BigfootDev/flatbuffers
1
0
Fork 1
mirror of https://github.com/google/flatbuffers.git synced 2026-06-05 04:58:57 +00:00
Code Issues Packages Projects Releases Wiki Activity

Refactor FieldDef to model presense as an enum rather than 2 bools. (#6420)

Browse Source 
* Define presence.

* Migrate to IsRequired and IsOptional methods

* moved stuff around

* Removed optional and required bools from FieldDef

* change assert to return error

* Fix tests.cpp

* MakeFieldPresence helper

* fmt

* old c++ compatibility stuff

Co-authored-by: Casper Neo <cneo@google.com>
This commit is contained in:
Casper
2021-01-25 12:29:43 -05:00
committed by GitHub
parent 0984d4328d
commit e581013e3d
14 changed files with 183 additions and 160 deletions
Download Patch File Download Diff File Expand all files Collapse all files

159
src/idl_parser.cpp
View File

@@ -800,34 +800,6 @@ CheckedError Parser::ParseField(StructDef &struct_def) {
"default values currently only supported for scalars in tables");
}
// Mark the optional scalars. Note that a side effect of ParseSingleValue is
// fixing field->value.constant to null.
if (IsScalar(type.base_type)) {
field->optional = (field->value.constant == "null");
if (field->optional) {
if (type.enum_def && type.enum_def->Lookup("null")) {
FLATBUFFERS_ASSERT(IsInteger(type.base_type));
return Error(
"the default 'null' is reserved for declaring optional scalar "
"fields, it conflicts with declaration of enum '" +
type.enum_def->name + "'.");
}
if (field->attributes.Lookup("key")) {
return Error(
"only a non-optional scalar field can be used as a 'key' field");
}
if (!SupportsOptionalScalars()) {
return Error(
"Optional scalars are not yet supported in at least one the of "
"the specified programming languages.");
}
}
} else {
// For nonscalars, only required fields are non-optional.
// At least until https://github.com/google/flatbuffers/issues/6053
field->optional = !field->required;
}
// Append .0 if the value has not it (skip hex and scientific floats).
// This suffix needed for generated C++ code.
if (IsFloat(type.base_type)) {
@@ -843,27 +815,6 @@ CheckedError Parser::ParseField(StructDef &struct_def) {
field->value.constant += ".0";
}
}
if (type.enum_def) {
// The type.base_type can only be scalar, union, array or vector.
// Table, struct or string can't have enum_def.
// Default value of union and vector in NONE, NULL translated to "0".
FLATBUFFERS_ASSERT(IsInteger(type.base_type) ||
(type.base_type == BASE_TYPE_UNION) || IsVector(type) ||
IsArray(type));
if (IsVector(type)) {
// Vector can't use initialization list.
FLATBUFFERS_ASSERT(field->value.constant == "0");
} else {
// All unions should have the NONE ("0") enum value.
auto in_enum = type.enum_def->attributes.Lookup("bit_flags") ||
field->IsScalarOptional() ||
type.enum_def->FindByValue(field->value.constant);
if (false == in_enum)
return Error("default value of " + field->value.constant +
" for field " + name + " is not part of enum " +
type.enum_def->name);
}
}
field->doc_comment = dc;
ECHECK(ParseMetaData(&field->attributes));
@@ -898,6 +849,75 @@ CheckedError Parser::ParseField(StructDef &struct_def) {
"hashing.");
}
}
// For historical convenience reasons, string keys are assumed required.
// Scalars are kDefault unless otherwise specified.
// Nonscalars are kOptional unless required;
field->key = field->attributes.Lookup("key") != nullptr;
const bool required = field->attributes.Lookup("required") != nullptr ||
(IsString(type) && field->key);
const bool optional =
IsScalar(type.base_type) ? (field->value.constant == "null") : !required;
if (required && optional) {
return Error("Fields cannot be both optional and required.");
}
field->presence = FieldDef::MakeFieldPresence(optional, required);
if (required && (struct_def.fixed || IsScalar(type.base_type))) {
return Error("only non-scalar fields in tables may be 'required'");
}
if (field->key) {
if (struct_def.has_key) return Error("only one field may be set as 'key'");
struct_def.has_key = true;
if (!IsScalar(type.base_type) && !IsString(type)) {
return Error("'key' field must be string or scalar type");
}
}
if (field->IsScalarOptional()) {
if (type.enum_def && type.enum_def->Lookup("null")) {
FLATBUFFERS_ASSERT(IsInteger(type.base_type));
return Error(
"the default 'null' is reserved for declaring optional scalar "
"fields, it conflicts with declaration of enum '" +
type.enum_def->name + "'.");
}
if (field->attributes.Lookup("key")) {
return Error(
"only a non-optional scalar field can be used as a 'key' field");
}
if (!SupportsOptionalScalars()) {
return Error(
"Optional scalars are not yet supported in at least one the of "
"the specified programming languages.");
}
}
if (type.enum_def) {
// The type.base_type can only be scalar, union, array or vector.
// Table, struct or string can't have enum_def.
// Default value of union and vector in NONE, NULL translated to "0".
FLATBUFFERS_ASSERT(IsInteger(type.base_type) ||
(type.base_type == BASE_TYPE_UNION) || IsVector(type) ||
IsArray(type));
if (IsVector(type)) {
// Vector can't use initialization list.
FLATBUFFERS_ASSERT(field->value.constant == "0");
} else {
// All unions should have the NONE ("0") enum value.
auto in_enum = field->IsOptional() ||
type.enum_def->attributes.Lookup("bit_flags") ||
type.enum_def->FindByValue(field->value.constant);
if (false == in_enum)
return Error("default value of " + field->value.constant +
" for field " + name + " is not part of enum " +
type.enum_def->name);
}
}
if (field->deprecated && struct_def.fixed)
return Error("can't deprecate fields in a struct");
auto cpp_type = field->attributes.Lookup("cpp_type");
if (cpp_type) {
if (!hash_name)
@@ -911,29 +931,7 @@ CheckedError Parser::ParseField(StructDef &struct_def) {
field->attributes.Add("cpp_ptr_type", val);
}
}
if (field->deprecated && struct_def.fixed)
return Error("can't deprecate fields in a struct");
field->required = field->attributes.Lookup("required") != nullptr;
if (field->required && (struct_def.fixed || IsScalar(type.base_type)))
return Error("only non-scalar fields in tables may be 'required'");
if (!IsScalar(type.base_type)) {
// For nonscalars, only required fields are non-optional.
// At least until https://github.com/google/flatbuffers/issues/6053
field->optional = !field->required;
}
field->key = field->attributes.Lookup("key") != nullptr;
if (field->key) {
if (struct_def.has_key) return Error("only one field may be set as 'key'");
struct_def.has_key = true;
if (!IsScalar(type.base_type)) {
field->required = true;
field->optional = false;
if (type.base_type != BASE_TYPE_STRING)
return Error("'key' field must be string or scalar type");
}
}
field->shared = field->attributes.Lookup("shared") != nullptr;
if (field->shared && field->value.type.base_type != BASE_TYPE_STRING)
return Error("shared can only be defined on strings");
@@ -972,7 +970,7 @@ CheckedError Parser::ParseField(StructDef &struct_def) {
if (typefield) {
if (!IsScalar(typefield->value.type.base_type)) {
// this is a union vector field
typefield->required = field->required;
typefield->presence = field->presence;
}
// If this field is a union, and it has a manually assigned id,
// the automatically added type field should have an id as well (of N - 1).
@@ -1267,7 +1265,7 @@ CheckedError Parser::ParseTable(const StructDef &struct_def, std::string *value,
for (auto field_it = struct_def.fields.vec.begin();
field_it != struct_def.fields.vec.end(); ++field_it) {
auto required_field = *field_it;
if (!required_field->required) { continue; }
if (!required_field->IsRequired()) { continue; }
bool found = false;
for (auto pf_it = field_stack_.end() - fieldn_outer;
pf_it != field_stack_.end(); ++pf_it) {
@@ -1299,7 +1297,7 @@ CheckedError Parser::ParseTable(const StructDef &struct_def, std::string *value,
if (!struct_def.sortbysize ||
size == SizeOf(field_value.type.base_type)) {
switch (field_value.type.base_type) {
// clang-format off
// clang-format off
#define FLATBUFFERS_TD(ENUM, IDLTYPE, CTYPE, ...) \
case BASE_TYPE_ ## ENUM: \
builder_.Pad(field->padding); \
@@ -1485,7 +1483,7 @@ CheckedError Parser::ParseVector(const Type &type, uoffset_t *ovalue,
// start at the back, since we're building the data backwards.
auto &val = field_stack_.back().first;
switch (val.type.base_type) {
// clang-format off
// clang-format off
#define FLATBUFFERS_TD(ENUM, IDLTYPE, CTYPE,...) \
case BASE_TYPE_ ## ENUM: \
if (IsStruct(val.type)) SerializeStruct(*val.type.struct_def, val); \
@@ -2792,7 +2790,9 @@ CheckedError Parser::ParseProtoFields(StructDef *struct_def, bool isextend,
}
if (!field) ECHECK(AddField(*struct_def, name, type, &field));
field->doc_comment = field_comment;
if (!IsScalar(type.base_type)) field->required = required;
if (!IsScalar(type.base_type) && required) {
field->presence = FieldDef::kRequired;
}
// See if there's a default specified.
if (Is('[')) {
NEXT();
@@ -3497,8 +3497,8 @@ Offset<reflection::Field> FieldDef::Serialize(FlatBufferBuilder *builder,
// Is uint64>max(int64) tested?
IsInteger(value.type.base_type) ? StringToInt(value.constant.c_str()) : 0,
// result may be platform-dependent if underlying is float (not double)
IsFloat(value.type.base_type) ? d : 0.0, deprecated, required, key,
attr__, docs__, optional);
IsFloat(value.type.base_type) ? d : 0.0, deprecated, IsRequired(), key,
attr__, docs__, IsOptional());
// TODO: value.constant is almost always "0", we could save quite a bit of
// space by sharing it. Same for common values of value.type.
}
@@ -3513,8 +3513,7 @@ bool FieldDef::Deserialize(Parser &parser, const reflection::Field *field) {
} else if (IsFloat(value.type.base_type)) {
value.constant = FloatToString(field->default_real(), 16);
}
deprecated = field->deprecated();
required = field->required();
presence = FieldDef::MakeFieldPresence(field->optional(), field->required());
key = field->key();
if (!DeserializeAttributes(parser, field->attributes())) return false;
// TODO: this should probably be handled by a separate attribute