/rust/registry/src/index.crates.io-6f17d22bba15001f/icu_provider-1.5.0/src/buf.rs

Source (jump to first uncovered line)
// This file is part of ICU4X. For terms of use, please see the file
// called LICENSE at the top level of the ICU4X source tree
// (online at: https://github.com/unicode-org/icu4x/blob/main/LICENSE ).

//! Traits for data providers that produce opaque buffers.

use crate::prelude::*;

/// [`DataMarker`] for raw buffers. Returned by [`BufferProvider`].
///
/// The data is expected to be deserialized before it can be used; see
/// [`DataPayload::into_deserialized`].
#[allow(clippy::exhaustive_structs)] // marker type
#[derive(Debug)]
pub struct BufferMarker;

impl DataMarker for BufferMarker {
    type Yokeable = &'static [u8];
}

/// A data provider that returns opaque bytes.
///
/// Generally, these bytes are expected to be deserializable with Serde. To get an object
/// implementing [`DataProvider`] via Serde, use [`as_deserializing()`].
///
/// Passing a  `BufferProvider` to a `*_with_buffer_provider` constructor requires enabling
/// the deserialization Cargo feature for the expected format(s):
/// - `deserialize_json`
/// - `deserialize_postcard_1`
/// - `deserialize_bincode_1`
///
/// Along with [`DataProvider`], this is one of the two foundational traits in this crate.
///
/// [`BufferProvider`] can be made into a trait object. It is used over FFI.
///
/// # Examples
///
/// ```
/// # #[cfg(feature = "deserialize_json")] {
/// use icu_locid::langid;
/// use icu_provider::hello_world::*;
/// use icu_provider::prelude::*;
/// use std::borrow::Cow;
///
/// let buffer_provider = HelloWorldProvider.into_json_provider();
///
/// let req = DataRequest {
///     locale: &langid!("de").into(),
///     metadata: Default::default(),
/// };
///
/// // Deserializing manually
/// assert_eq!(
///     serde_json::from_slice::<HelloWorldV1>(
///         buffer_provider
///             .load_buffer(HelloWorldV1Marker::KEY, req)
///             .expect("load should succeed")
///             .take_payload()
///             .unwrap()
///             .get()
///     )
///     .expect("should deserialize"),
///     HelloWorldV1 {
///         message: Cow::Borrowed("Hallo Welt"),
///     },
/// );
///
/// // Deserialize automatically
/// let deserializing_provider: &dyn DataProvider<HelloWorldV1Marker> =
///     &buffer_provider.as_deserializing();
///
/// assert_eq!(
///     deserializing_provider
///         .load(req)
///         .expect("load should succeed")
///         .take_payload()
///         .unwrap()
///         .get(),
///     &HelloWorldV1 {
///         message: Cow::Borrowed("Hallo Welt"),
///     },
/// );
/// # }
/// ```
///
/// [`as_deserializing()`]: AsDeserializingBufferProvider::as_deserializing
pub trait BufferProvider {
    /// Loads a [`DataPayload`]`<`[`BufferMarker`]`>` according to the key and request.
    fn load_buffer(
        &self,
        key: DataKey,
        req: DataRequest,
    ) -> Result<DataResponse<BufferMarker>, DataError>;
}

impl<'a, T: BufferProvider + ?Sized> BufferProvider for &'a T {
    #[inline]
    fn load_buffer(
        &self,
        key: DataKey,
        req: DataRequest,
    ) -> Result<DataResponse<BufferMarker>, DataError> {
        (**self).load_buffer(key, req)
    }
}

impl<T: BufferProvider + ?Sized> BufferProvider for alloc::boxed::Box<T> {
    #[inline]
    fn load_buffer(
        &self,
        key: DataKey,
        req: DataRequest,
    ) -> Result<DataResponse<BufferMarker>, DataError> {
        (**self).load_buffer(key, req)
    }
}

impl<T: BufferProvider + ?Sized> BufferProvider for alloc::rc::Rc<T> {
    #[inline]
    fn load_buffer(
        &self,
        key: DataKey,
        req: DataRequest,
    ) -> Result<DataResponse<BufferMarker>, DataError> {
        (**self).load_buffer(key, req)
    }
}

#[cfg(target_has_atomic = "ptr")]
impl<T: BufferProvider + ?Sized> BufferProvider for alloc::sync::Arc<T> {
    #[inline]
    fn load_buffer(
        &self,
        key: DataKey,
        req: DataRequest,
    ) -> Result<DataResponse<BufferMarker>, DataError> {
        (**self).load_buffer(key, req)
    }
}

/// An enum expressing all Serde formats known to ICU4X.
#[derive(Debug, PartialEq, Eq, Hash, Copy, Clone)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
#[non_exhaustive]
pub enum BufferFormat {
    /// Serialize using JavaScript Object Notation (JSON).
    Json,
    /// Serialize using Bincode version 1.
    Bincode1,
    /// Serialize using Postcard version 1.
    Postcard1,
}

impl BufferFormat {
    /// Returns an error if the buffer format is not enabled.
    pub fn check_available(&self) -> Result<(), DataError> {
        match self {
            #[cfg(feature = "deserialize_json")]
            BufferFormat::Json => Ok(()),

            #[cfg(feature = "deserialize_bincode_1")]
            BufferFormat::Bincode1 => Ok(()),

            #[cfg(feature = "deserialize_postcard_1")]
            BufferFormat::Postcard1 => Ok(()),

            // Allowed for cases in which all features are enabled
            #[allow(unreachable_patterns)]
            _ => Err(DataErrorKind::UnavailableBufferFormat(*self).into_error()),
        }
    }
}

Line	Count	Source (jump to first uncovered line)
1		// This file is part of ICU4X. For terms of use, please see the file
2		// called LICENSE at the top level of the ICU4X source tree
3		// (online at: https://github.com/unicode-org/icu4x/blob/main/LICENSE ).
4
5		//! Traits for data providers that produce opaque buffers.
6
7		use crate::prelude::*;
8
9		/// [`DataMarker`] for raw buffers. Returned by [`BufferProvider`].
10		///
11		/// The data is expected to be deserialized before it can be used; see
12		/// [`DataPayload::into_deserialized`].
13		#[allow(clippy::exhaustive_structs)] // marker type
14		#[derive(Debug)]
15		pub struct BufferMarker;
16
17		impl DataMarker for BufferMarker {
18		type Yokeable = &'static [u8];
19		}
20
21		/// A data provider that returns opaque bytes.
22		///
23		/// Generally, these bytes are expected to be deserializable with Serde. To get an object
24		/// implementing [`DataProvider`] via Serde, use [`as_deserializing()`].
25		///
26		/// Passing a `BufferProvider` to a `*_with_buffer_provider` constructor requires enabling
27		/// the deserialization Cargo feature for the expected format(s):
28		/// - `deserialize_json`
29		/// - `deserialize_postcard_1`
30		/// - `deserialize_bincode_1`
31		///
32		/// Along with [`DataProvider`], this is one of the two foundational traits in this crate.
33		///
34		/// [`BufferProvider`] can be made into a trait object. It is used over FFI.
35		///
36		/// # Examples
37		///
38		/// ```
39		/// # #[cfg(feature = "deserialize_json")] {
40		/// use icu_locid::langid;
41		/// use icu_provider::hello_world::*;
42		/// use icu_provider::prelude::*;
43		/// use std::borrow::Cow;
44		///
45		/// let buffer_provider = HelloWorldProvider.into_json_provider();
46		///
47		/// let req = DataRequest {
48		/// locale: &langid!("de").into(),
49		/// metadata: Default::default(),
50		/// };
51		///
52		/// // Deserializing manually
53		/// assert_eq!(
54		/// serde_json::from_slice::<HelloWorldV1>(
55		/// buffer_provider
56		/// .load_buffer(HelloWorldV1Marker::KEY, req)
57		/// .expect("load should succeed")
58		/// .take_payload()
59		/// .unwrap()
60		/// .get()
61		/// )
62		/// .expect("should deserialize"),
63		/// HelloWorldV1 {
64		/// message: Cow::Borrowed("Hallo Welt"),
65		/// },
66		/// );
67		///
68		/// // Deserialize automatically
69		/// let deserializing_provider: &dyn DataProvider<HelloWorldV1Marker> =
70		/// &buffer_provider.as_deserializing();
71		///
72		/// assert_eq!(
73		/// deserializing_provider
74		/// .load(req)
75		/// .expect("load should succeed")
76		/// .take_payload()
77		/// .unwrap()
78		/// .get(),
79		/// &HelloWorldV1 {
80		/// message: Cow::Borrowed("Hallo Welt"),
81		/// },
82		/// );
83		/// # }
84		/// ```
85		///
86		/// [`as_deserializing()`]: AsDeserializingBufferProvider::as_deserializing
87		pub trait BufferProvider {
88		/// Loads a [`DataPayload`]`<`[`BufferMarker`]`>` according to the key and request.
89		fn load_buffer(
90		&self,
91		key: DataKey,
92		req: DataRequest,
93		) -> Result<DataResponse<BufferMarker>, DataError>;
94		}
95
96		impl<'a, T: BufferProvider + ?Sized> BufferProvider for &'a T {
97		#[inline]
98	0	fn load_buffer(
99	0	&self,
100	0	key: DataKey,
101	0	req: DataRequest,
102	0	) -> Result<DataResponse<BufferMarker>, DataError> {
103	0	(**self).load_buffer(key, req)
104	0	}
105		}
106
107		impl<T: BufferProvider + ?Sized> BufferProvider for alloc::boxed::Box<T> {
108		#[inline]
109	0	fn load_buffer(
110	0	&self,
111	0	key: DataKey,
112	0	req: DataRequest,
113	0	) -> Result<DataResponse<BufferMarker>, DataError> {
114	0	(**self).load_buffer(key, req)
115	0	}
116		}
117
118		impl<T: BufferProvider + ?Sized> BufferProvider for alloc::rc::Rc<T> {
119		#[inline]
120	0	fn load_buffer(
121	0	&self,
122	0	key: DataKey,
123	0	req: DataRequest,
124	0	) -> Result<DataResponse<BufferMarker>, DataError> {
125	0	(**self).load_buffer(key, req)
126	0	}
127		}
128
129		#[cfg(target_has_atomic = "ptr")]
130		impl<T: BufferProvider + ?Sized> BufferProvider for alloc::sync::Arc<T> {
131		#[inline]
132	0	fn load_buffer(
133	0	&self,
134	0	key: DataKey,
135	0	req: DataRequest,
136	0	) -> Result<DataResponse<BufferMarker>, DataError> {
137	0	(**self).load_buffer(key, req)
138	0	}
139		}
140
141		/// An enum expressing all Serde formats known to ICU4X.
142		#[derive(Debug, PartialEq, Eq, Hash, Copy, Clone)]
143		#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
144		#[non_exhaustive]
145		pub enum BufferFormat {
146		/// Serialize using JavaScript Object Notation (JSON).
147		Json,
148		/// Serialize using Bincode version 1.
149		Bincode1,
150		/// Serialize using Postcard version 1.
151		Postcard1,
152		}
153
154		impl BufferFormat {
155		/// Returns an error if the buffer format is not enabled.
156	0	pub fn check_available(&self) -> Result<(), DataError> {
157	0	match self {
158	0	#[cfg(feature = "deserialize_json")]
159	0	BufferFormat::Json => Ok(()),
160	0
161	0	#[cfg(feature = "deserialize_bincode_1")]
162	0	BufferFormat::Bincode1 => Ok(()),
163	0
164	0	#[cfg(feature = "deserialize_postcard_1")]
165	0	BufferFormat::Postcard1 => Ok(()),
166	0
167	0	// Allowed for cases in which all features are enabled
168	0	#[allow(unreachable_patterns)]
169	0	_ => Err(DataErrorKind::UnavailableBufferFormat(*self).into_error()),
170	0	}
171	0	}
172		}

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Created: 2025-05-08 06:13