snarkvm_circuit_program/data/identifier/
mod.rs

1// Copyright (c) 2019-2025 Provable Inc.
2// This file is part of the snarkVM library.
3
4// Licensed under the Apache License, Version 2.0 (the "License");
5// you may not use this file except in compliance with the License.
6// You may obtain a copy of the License at:
7
8// http://www.apache.org/licenses/LICENSE-2.0
9
10// Unless required by applicable law or agreed to in writing, software
11// distributed under the License is distributed on an "AS IS" BASIS,
12// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13// See the License for the specific language governing permissions and
14// limitations under the License.
15
16#[cfg(test)]
17use snarkvm_circuit_types::environment::assert_scope;
18
19mod equal;
20mod from_bits;
21mod from_field;
22mod size_in_bits;
23mod to_bits;
24mod to_field;
25
26use snarkvm_circuit_network::Aleo;
27use snarkvm_circuit_types::{Boolean, Field, U8, environment::prelude::*};
28use snarkvm_utilities::ToBits as TB;
29
30/// An identifier is an **immutable** UTF-8 string,
31/// represented as a **constant** field element in the circuit.
32///
33/// # Requirements
34/// The identifier must not be an empty string.
35/// The identifier must not start with a number.
36/// The identifier must be alphanumeric, and may include underscores.
37/// The identifier must not consist solely of underscores.
38/// The identifier must fit within the data capacity of a base field element.
39#[derive(Clone)]
40pub struct Identifier<A: Aleo>(Field<A>, u8); // Number of bytes in the identifier.
41
42impl<A: Aleo> Inject for Identifier<A> {
43    type Primitive = console::Identifier<A::Network>;
44
45    /// Initializes a new identifier from a string.
46    /// Note: Identifiers are always `Mode::Constant`.
47    fn new(_: Mode, identifier: Self::Primitive) -> Self {
48        // Convert the identifier to a string to check its validity.
49        let identifier = identifier.to_string();
50
51        // Note: The string bytes themselves are **not** little-endian. Rather, they are order-preserving
52        // for reconstructing the string when recovering the field element back into bytes.
53        let field = Field::from_bits_le(&Vec::<Boolean<_>>::constant(identifier.to_bits_le()));
54
55        // Return the identifier.
56        Self(field, identifier.len() as u8)
57    }
58}
59
60impl<A: Aleo> Eject for Identifier<A> {
61    type Primitive = console::Identifier<A::Network>;
62
63    /// Ejects the mode of the identifier.
64    fn eject_mode(&self) -> Mode {
65        debug_assert!(self.0.eject_mode() == Mode::Constant, "Identifier::eject_mode - Mode must be 'Constant'");
66        Mode::Constant
67    }
68
69    /// Ejects the identifier as a string.
70    fn eject_value(&self) -> Self::Primitive {
71        match console::FromField::from_field(&self.0.eject_value()) {
72            Ok(identifier) => identifier,
73            Err(error) => A::halt(format!("Failed to convert an identifier to a string: {error}")),
74        }
75    }
76}
77
78impl<A: Aleo> Parser for Identifier<A> {
79    /// Parses a UTF-8 string into an identifier.
80    #[inline]
81    fn parse(string: &str) -> ParserResult<Self> {
82        // Parse the identifier from the string.
83        let (string, identifier) = console::Identifier::parse(string)?;
84
85        Ok((string, Identifier::constant(identifier)))
86    }
87}
88
89impl<A: Aleo> FromStr for Identifier<A> {
90    type Err = Error;
91
92    /// Parses a UTF-8 string into an identifier.
93    #[inline]
94    fn from_str(string: &str) -> Result<Self> {
95        match Self::parse(string) {
96            Ok((remainder, object)) => {
97                // Ensure the remainder is empty.
98                ensure!(remainder.is_empty(), "Failed to parse string. Found invalid character in: \"{remainder}\"");
99                // Return the object.
100                Ok(object)
101            }
102            Err(error) => bail!("Failed to parse string. {error}"),
103        }
104    }
105}
106
107impl<A: Aleo> Debug for Identifier<A> {
108    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
109        Display::fmt(self, f)
110    }
111}
112
113impl<A: Aleo> Display for Identifier<A> {
114    /// Prints the identifier as a string.
115    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
116        write!(f, "{}", self.eject_value())
117    }
118}
119
120impl<A: Aleo> Eq for Identifier<A> {}
121
122impl<A: Aleo> PartialEq for Identifier<A> {
123    /// Implements the `Eq` trait for the identifier.
124    fn eq(&self, other: &Self) -> bool {
125        self.0.eject_value() == other.0.eject_value()
126    }
127}
128
129impl<A: Aleo> core::hash::Hash for Identifier<A> {
130    /// Implements the `Hash` trait for the identifier.
131    fn hash<H: core::hash::Hasher>(&self, state: &mut H) {
132        self.0.eject_value().hash(state);
133    }
134}
135
136impl<A: Aleo> From<Identifier<A>> for LinearCombination<A::BaseField> {
137    /// Note: Identifier is always `Mode::Constant`.
138    fn from(identifier: Identifier<A>) -> Self {
139        From::from(&identifier)
140    }
141}
142
143impl<A: Aleo> From<&Identifier<A>> for LinearCombination<A::BaseField> {
144    /// Note: Identifier is always `Mode::Constant`.
145    fn from(identifier: &Identifier<A>) -> Self {
146        LinearCombination::from(&identifier.0)
147    }
148}
149
150#[cfg(test)]
151pub(crate) mod tests {
152    use super::*;
153    use crate::Circuit;
154    use console::{Rng, TestRng};
155
156    use anyhow::{Result, bail};
157    use core::str::FromStr;
158    use rand::distributions::Alphanumeric;
159
160    /// Samples a random identifier.
161    pub(crate) fn sample_console_identifier<A: Aleo>() -> Result<console::Identifier<A::Network>> {
162        // Sample a random fixed-length alphanumeric string, that always starts with an alphabetic character.
163        let string = sample_console_identifier_as_string::<A>()?;
164        // Return the identifier.
165        console::Identifier::from_str(&string)
166    }
167
168    /// Samples a random identifier as a string.
169    pub(crate) fn sample_console_identifier_as_string<A: Aleo>() -> Result<String> {
170        // Initialize a test RNG.
171        let rng = &mut TestRng::default();
172        // Sample a random fixed-length alphanumeric string, that always starts with an alphabetic character.
173        let string = "a".to_string()
174            + &rng
175                .sample_iter(&Alphanumeric)
176                .take(A::BaseField::size_in_data_bits() / (8 * 2))
177                .map(char::from)
178                .collect::<String>();
179        // Ensure identifier fits within the data capacity of the base field.
180        let max_bytes = A::BaseField::size_in_data_bits() / 8; // Note: This intentionally rounds down.
181        match string.len() <= max_bytes {
182            // Return the identifier.
183            true => Ok(string),
184            false => bail!("Identifier exceeds the maximum capacity allowed"),
185        }
186    }
187
188    /// Samples a random identifier as a string.
189    pub(crate) fn sample_lowercase_console_identifier_as_string<A: Aleo>() -> Result<String> {
190        // Sample a random identifier.
191        let string = sample_console_identifier_as_string::<A>()?;
192        // Return the identifier as lowercase.
193        Ok(string.to_lowercase())
194    }
195
196    #[test]
197    fn test_identifier_parse() -> Result<()> {
198        let candidate = Identifier::<Circuit>::parse("foo_bar").unwrap();
199        assert_eq!("", candidate.0);
200        assert_eq!(Identifier::<Circuit>::constant("foo_bar".try_into()?).eject(), candidate.1.eject());
201        Ok(())
202    }
203
204    #[test]
205    fn test_identifier_parse_fails() -> Result<()> {
206        // Must be alphanumeric or underscore.
207        let identifier = Identifier::<Circuit>::parse("foo_bar~baz").unwrap();
208        assert_eq!(("~baz", Identifier::<Circuit>::from_str("foo_bar")?.eject()), (identifier.0, identifier.1.eject()));
209        let identifier = Identifier::<Circuit>::parse("foo_bar-baz").unwrap();
210        assert_eq!(("-baz", Identifier::<Circuit>::from_str("foo_bar")?.eject()), (identifier.0, identifier.1.eject()));
211
212        // Must not be solely underscores.
213        assert!(Identifier::<Circuit>::parse("_").is_err());
214        assert!(Identifier::<Circuit>::parse("__").is_err());
215        assert!(Identifier::<Circuit>::parse("___").is_err());
216        assert!(Identifier::<Circuit>::parse("____").is_err());
217
218        // Must not start with a number.
219        assert!(Identifier::<Circuit>::parse("1").is_err());
220        assert!(Identifier::<Circuit>::parse("2").is_err());
221        assert!(Identifier::<Circuit>::parse("3").is_err());
222        assert!(Identifier::<Circuit>::parse("1foo").is_err());
223        assert!(Identifier::<Circuit>::parse("12").is_err());
224        assert!(Identifier::<Circuit>::parse("111").is_err());
225
226        // Must fit within the data capacity of a base field element.
227        let identifier =
228            Identifier::<Circuit>::parse("foo_bar_baz_qux_quux_quuz_corge_grault_garply_waldo_fred_plugh_xyzzy");
229        assert!(identifier.is_err());
230        Ok(())
231    }
232
233    #[test]
234    fn test_identifier_display() -> Result<()> {
235        let identifier = Identifier::<Circuit>::from_str("foo_bar")?;
236        assert_eq!("foo_bar", format!("{identifier}"));
237        Ok(())
238    }
239
240    #[test]
241    fn test_identifier_bits() -> Result<()> {
242        let identifier = Identifier::<Circuit>::from_str("foo_bar")?;
243        assert_eq!(
244            identifier.to_bits_le().eject(),
245            Identifier::from_bits_le(&identifier.to_bits_le()).to_bits_le().eject()
246        );
247        assert_eq!(
248            identifier.to_bits_be().eject(),
249            Identifier::from_bits_be(&identifier.to_bits_be()).to_bits_be().eject()
250        );
251        Ok(())
252    }
253}
snarkvm_circuit_program/data/identifier/mod.rs

snarkvm_circuit_program/data/identifier/
mod.rs
