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{#
# Python has a built-in `enum` module which is nice to use, but doesn't support
# variants with associated data. So, we switch here, and generate a stdlib `enum`
# when none of the variants have associated data, or a generic nested-class
# construct when they do.
#}
{%- let type_name = e.self_type.type_name %}
{%- let uniffi_trait_methods = e.uniffi_trait_methods %}
{% if e.is_flat %}
class {{ type_name }}(enum.Enum):
{{ e.docstring|docstring(4) -}}
{%- for variant in e.variants %}
{{ variant.name }} = {{ variant.discr.py_lit }}
{{ variant.docstring|docstring(4) -}}
{% endfor %}
{%- for meth in e.methods -%}
{%- let callable = meth.callable %}
{% if callable.is_async %}async {% endif %}def {{ callable.name }}(self, {% include "CallableArgs.py" %}) -> {{ callable.return_type.type_name }}:
{{ meth.docstring|docstring(8) -}}
{%- filter indent(8) %}
{%- include "CallableBody.py" %}
{%- endfilter %}
{%- endfor %}
{% else %}
class {{ type_name }}:
{{ e.docstring|docstring(4) -}}
def __init__(self):
raise RuntimeError("{{ type_name }} cannot be instantiated directly")
# Each enum variant is a nested class of the enum itself.
{% for variant in e.variants -%}
@dataclass
class {{ variant.name }}:
{{ variant.docstring|docstring(8) -}}
{%- if variant.has_unnamed_fields() %}
def __init__(self, *values):
if len(values) != {{ variant.fields.len() }}:
raise TypeError(f"Expected {{ variant.fields.len() }} arguments, found {len(values)}")
self._values = values
def __getitem__(self, index):
return self._values[index]
{% filter indent(8) %}
{% include "UniffiTraitImpls.py" %}
{% endfilter %}
{# "builtin" methods not handled by a uniffi_trait #}
{%- if uniffi_trait_methods.display_fmt.is_none() %}
def __str__(self):
return f"{{ type_name }}.{{ variant.name }}{self._values!r}"
{%- endif %}
{%- if uniffi_trait_methods.eq_eq.is_none() %}
def __eq__(self, other):
if not isinstance(other, {{ type_name }}):
return NotImplemented
if not other.is_{{ variant.name }}():
return False
return self._values == other._values
{%- endif %}
{%- else %}
def __init__(self, {% for field in variant.fields %}
{{- field.name }}: {{- field.ty.type_name}}
{%- if let Some(default) = field.default %} = {{ default.arg_literal }}{% endif %}
{%- if !loop.last %}, {% endif %}
{%- endfor %}):
{%- for field in variant.fields %}
{%- match field.default %}
{%- when None %}
self.{{ field.name }} = {{ field.name }}
{%- when Some(default) %}
{%- if default.is_arg_literal %}
self.{{ field.name }} = {{ field.name }}
{%- else %}
if {{ field.name }} is {{ default.arg_literal }}:
self.{{ field.name }} = {{ default.py_default }}
else:
self.{{ field.name }} = {{ field.name }}
{%- endif %}
{%- endmatch %}
{# not sure what to do with docstrings - see #2552, suggests putting them after the field init #}
{{ field.docstring|docstring(8) -}}
{%- endfor %}
pass
{% filter indent(8) %}
{% include "UniffiTraitImpls.py" %}
{% endfilter %}
{# "builtin" methods not handled by a uniffi_trait #}
{%- if uniffi_trait_methods.display_fmt.is_none() %}
def __str__(self):
return "{{ type_name }}.{{ variant.name }}({% for field in variant.fields %}{{ field.name }}={}{% if loop.last %}{% else %}, {% endif %}{% endfor %})".format({% for field in variant.fields %}self.{{ field.name }}{% if loop.last %}{% else %}, {% endif %}{% endfor %})
{%- endif %}
{%- if uniffi_trait_methods.eq_eq.is_none() %}
def __eq__(self, other):
if not isinstance(other, {{ type_name }}):
return NotImplemented
if not other.is_{{ variant.name }}():
return False
{%- for field in variant.fields %}
if self.{{ field.name }} != other.{{ field.name }}:
return False
{%- endfor %}
return True
{%- endif %}
{%- endif %}
{% endfor %}
# For each variant, we have `is_NAME` and `is_name` methods for easily checking
# whether an instance is that variant.
{% for variant in e.variants -%}
def is_{{ variant.name }}(self) -> bool:
return isinstance(self, {{ type_name }}.{{ variant.name }})
{#- We used to think we used `is_NAME` but did `is_name` instead. In #2270 we decided to do both. #}
{%- if variant.name != variant.name.to_snake_case() %}
def is_{{ variant.name.to_snake_case() }}(self) -> bool:
return isinstance(self, {{ type_name }}.{{ variant.name }})
{%- endif %}
{% endfor %}
{%- for meth in e.methods -%}
{%- let callable = meth.callable %}
{% if callable.is_async %}async {% endif %}def {{ callable.name }}(self, {% include "CallableArgs.py" %}) -> {{ callable.return_type.type_name }}:
{{ meth.docstring|docstring(8) -}}
{%- filter indent(8) %}
{%- include "CallableBody.py" %}
{%- endfilter %}
{%- endfor %}
# Now, a little trick - we make each nested variant class be a subclass of the main
# enum class, so that method calls and instance checks etc will work intuitively.
# We might be able to do this a little more neatly with a metaclass, but this'll do.
{% for variant in e.variants -%}
{{ type_name }}.{{ variant.name }} = type("{{ type_name }}.{{ variant.name }}", ({{ type_name }}.{{variant.name}}, {{ type_name }},), {}) # type: ignore
{% endfor %}
{% endif %}
class {{ e.self_type.ffi_converter_name }}(_UniffiConverterRustBuffer):
@staticmethod
def read(buf):
variant = buf.read_i32()
{%- for variant in e.variants %}
if variant == {{ loop.index }}:
{%- if e.is_flat %}
return {{ type_name }}.{{variant.name}}
{%- else %}
return {{ type_name }}.{{variant.name}}(
{%- for field in variant.fields %}
{{ field.ty.ffi_converter_name }}.read(buf),
{%- endfor %}
)
{%- endif %}
{%- endfor %}
raise InternalError("Raw enum value doesn't match any cases")
@staticmethod
def check_lower(value):
{%- if e.variants.is_empty() %}
pass
{%- else %}
{%- for variant in e.variants %}
{%- if e.is_flat %}
if value == {{ type_name }}.{{ variant.name }}:
{%- else %}
if value.is_{{ variant.name }}():
{%- endif %}
{%- for field in variant.fields %}
{%- if variant.has_unnamed_fields() %}
{{ field.ty.ffi_converter_name }}.check_lower(value._values[{{ loop.index0 }}])
{%- else %}
{{ field.ty.ffi_converter_name }}.check_lower(value.{{ field.name }})
{%- endif %}
{%- endfor %}
return
{%- endfor %}
raise ValueError(value)
{%- endif %}
@staticmethod
def write(value, buf):
{%- for variant in e.variants %}
{%- if e.is_flat %}
if value == {{ type_name }}.{{ variant.name }}:
buf.write_i32({{ loop.index }})
{%- else %}
if value.is_{{ variant.name }}():
buf.write_i32({{ loop.index }})
{%- for field in variant.fields %}
{%- if variant.has_unnamed_fields() %}
{{ field.ty.ffi_converter_name }}.write(value._values[{{ loop.index0 }}], buf)
{%- else %}
{{ field.ty.ffi_converter_name }}.write(value.{{ field.name }}, buf)
{%- endif %}
{%- endfor %}
{%- endif %}
{%- endfor %}