surrealdb_core/sql/
strand.rs

1use crate::err::Error;
2use revision::revisioned;
3use serde::{Deserialize, Serialize};
4use std::fmt::{self, Display, Formatter};
5use std::ops::Deref;
6use std::ops::{self};
7use std::str;
8
9use super::escape::QuoteStr;
10use super::value::TryAdd;
11
12pub(crate) const TOKEN: &str = "$surrealdb::private::sql::Strand";
13
14/// A string that doesn't contain NUL bytes.
15#[revisioned(revision = 1)]
16#[derive(Clone, Debug, Default, Eq, PartialEq, Ord, PartialOrd, Serialize, Deserialize, Hash)]
17#[serde(rename = "$surrealdb::private::sql::Strand")]
18#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
19#[non_exhaustive]
20pub struct Strand(#[serde(with = "no_nul_bytes")] pub String);
21
22impl Strand {
23	/// Create a new strand, returns None if the string contains a null byte.
24	pub fn new(s: String) -> Option<Strand> {
25		if s.contains('\0') {
26			None
27		} else {
28			Some(Strand(s))
29		}
30	}
31
32	/// Create a new strand, without checking the string.
33	///
34	/// # Safety
35	/// Caller must ensure that string handed as an argument does not contain any null bytes.
36	pub unsafe fn new_unchecked(s: String) -> Strand {
37		// Check in debug mode if the variants
38		debug_assert!(!s.contains('\0'));
39		Strand(s)
40	}
41}
42
43impl From<String> for Strand {
44	fn from(s: String) -> Self {
45		// TODO: For now, fix this in the future.
46		unsafe { Self::new_unchecked(s) }
47	}
48}
49
50impl From<&str> for Strand {
51	fn from(s: &str) -> Self {
52		// TODO: For now, fix this in the future.
53		unsafe { Self::new_unchecked(s.to_string()) }
54	}
55}
56
57impl Deref for Strand {
58	type Target = String;
59	fn deref(&self) -> &Self::Target {
60		&self.0
61	}
62}
63
64impl From<Strand> for String {
65	fn from(s: Strand) -> Self {
66		s.0
67	}
68}
69
70impl Strand {
71	/// Get the underlying String slice
72	pub fn as_str(&self) -> &str {
73		self.0.as_str()
74	}
75	/// Returns the underlying String
76	pub fn as_string(self) -> String {
77		self.0
78	}
79	/// Convert the Strand to a raw String
80	pub fn to_raw(self) -> String {
81		self.0
82	}
83}
84
85impl Display for Strand {
86	fn fmt(&self, f: &mut Formatter) -> fmt::Result {
87		QuoteStr(&self.0).fmt(f)
88	}
89}
90
91impl ops::Add for Strand {
92	type Output = Self;
93	fn add(mut self, other: Self) -> Self {
94		self.0.push_str(other.as_str());
95		self
96	}
97}
98
99impl TryAdd for Strand {
100	type Output = Self;
101	fn try_add(mut self, other: Self) -> Result<Self, Error> {
102		if self.0.try_reserve(other.len()).is_ok() {
103			self.0.push_str(other.as_str());
104			Ok(self)
105		} else {
106			Err(Error::InsufficientReserve(format!(
107				"additional string of length {} bytes",
108				other.0.len()
109			)))
110		}
111	}
112}
113
114// serde(with = no_nul_bytes) will (de)serialize with no NUL bytes.
115pub(crate) mod no_nul_bytes {
116	use serde::{
117		de::{self, Visitor},
118		Deserializer, Serializer,
119	};
120	use std::fmt;
121
122	pub(crate) fn serialize<S>(s: &str, serializer: S) -> Result<S::Ok, S::Error>
123	where
124		S: Serializer,
125	{
126		if s.contains('\0') {
127			return Err(<S::Error as serde::ser::Error>::custom(
128				"to be serialized string contained a null byte",
129			));
130		}
131		serializer.serialize_str(s)
132	}
133
134	pub(crate) fn deserialize<'de, D>(deserializer: D) -> Result<String, D::Error>
135	where
136		D: Deserializer<'de>,
137	{
138		struct NoNulBytesVisitor;
139
140		impl Visitor<'_> for NoNulBytesVisitor {
141			type Value = String;
142
143			fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
144				formatter.write_str("a string without any NUL bytes")
145			}
146
147			fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
148			where
149				E: de::Error,
150			{
151				if value.contains('\0') {
152					Err(de::Error::custom("contained NUL byte"))
153				} else {
154					Ok(value.to_owned())
155				}
156			}
157
158			fn visit_string<E>(self, value: String) -> Result<Self::Value, E>
159			where
160				E: de::Error,
161			{
162				if value.contains('\0') {
163					Err(de::Error::custom("contained NUL byte"))
164				} else {
165					Ok(value)
166				}
167			}
168		}
169
170		deserializer.deserialize_string(NoNulBytesVisitor)
171	}
172}
surrealdb_core/sql/strand.rs

surrealdb_core/sql/
strand.rs
