snarkvm_synthesizer_program/logic/command/
get_or_use.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
16use crate::{CallOperator, FinalizeStoreTrait, Opcode, Operand, RegistersTrait, StackTrait};
17use console::{
18    network::prelude::*,
19    program::{Register, Value},
20};
21
22/// A get command that uses the provided default in case of failure, e.g. `get.or_use accounts[r0] r1 into r2;`.
23/// Gets the value stored at `operand` in `mapping` and stores the result in `destination`.
24/// If the key is not present, `default` is stored in `destination`.
25#[derive(Clone, PartialEq, Eq, Hash)]
26pub struct GetOrUse<N: Network> {
27    /// The mapping.
28    mapping: CallOperator<N>,
29    /// The operands.
30    operands: [Operand<N>; 2],
31    /// The destination register.
32    destination: Register<N>,
33}
34
35impl<N: Network> GetOrUse<N> {
36    /// Returns the opcode.
37    #[inline]
38    pub const fn opcode() -> Opcode {
39        Opcode::Command("get.or_use")
40    }
41
42    /// Returns the operands in the operation.
43    #[inline]
44    pub fn operands(&self) -> &[Operand<N>] {
45        &self.operands
46    }
47
48    /// Returns the mapping.
49    #[inline]
50    pub const fn mapping(&self) -> &CallOperator<N> {
51        &self.mapping
52    }
53
54    /// Returns the operand containing the key.
55    #[inline]
56    pub const fn key(&self) -> &Operand<N> {
57        &self.operands[0]
58    }
59
60    /// Returns the default value.
61    #[inline]
62    pub const fn default(&self) -> &Operand<N> {
63        &self.operands[1]
64    }
65
66    /// Returns the destination register.
67    #[inline]
68    pub const fn destination(&self) -> &Register<N> {
69        &self.destination
70    }
71}
72
73impl<N: Network> GetOrUse<N> {
74    /// Finalizes the command.
75    #[inline]
76    pub fn finalize(
77        &self,
78        stack: &impl StackTrait<N>,
79        store: &impl FinalizeStoreTrait<N>,
80        registers: &mut impl RegistersTrait<N>,
81    ) -> Result<()> {
82        // Determine the program ID and mapping name.
83        let (program_id, mapping_name) = match self.mapping {
84            CallOperator::Locator(locator) => (*locator.program_id(), *locator.resource()),
85            CallOperator::Resource(mapping_name) => (*stack.program_id(), mapping_name),
86        };
87
88        // Ensure the mapping exists.
89        if !store.contains_mapping_speculative(&program_id, &mapping_name)? {
90            bail!("Mapping '{program_id}/{mapping_name}' does not exist");
91        }
92
93        // Load the operand as a plaintext.
94        let key = registers.load_plaintext(stack, self.key())?;
95
96        // Retrieve the value from storage as a literal.
97        let value = match store.get_value_speculative(program_id, mapping_name, &key)? {
98            Some(Value::Plaintext(plaintext)) => Value::Plaintext(plaintext),
99            Some(Value::Record(..)) => bail!("Cannot 'get.or_use' a 'record'"),
100            Some(Value::Future(..)) => bail!("Cannot 'get.or_use' a 'future'"),
101            // If a key does not exist, then use the default value.
102            None => Value::Plaintext(registers.load_plaintext(stack, self.default())?),
103        };
104
105        // Assign the value to the destination register.
106        registers.store(stack, &self.destination, value)?;
107
108        // Return the finalize operation.
109        Ok(())
110    }
111}
112
113impl<N: Network> Parser for GetOrUse<N> {
114    /// Parses a string into an operation.
115    #[inline]
116    fn parse(string: &str) -> ParserResult<Self> {
117        // Parse the whitespace and comments from the string.
118        let (string, _) = Sanitizer::parse(string)?;
119        // Parse the opcode from the string.
120        let (string, _) = tag(*Self::opcode())(string)?;
121        // Parse the whitespace from the string.
122        let (string, _) = Sanitizer::parse_whitespaces(string)?;
123
124        // Parse the mapping name from the string.
125        let (string, mapping) = CallOperator::parse(string)?;
126        // Parse the "[" from the string.
127        let (string, _) = tag("[")(string)?;
128        // Parse the whitespace from the string.
129        let (string, _) = Sanitizer::parse_whitespaces(string)?;
130        // Parse the key operand from the string.
131        let (string, key) = Operand::parse(string)?;
132        // Parse the whitespace from the string.
133        let (string, _) = Sanitizer::parse_whitespaces(string)?;
134        // Parse the "]" from the string.
135        let (string, _) = tag("]")(string)?;
136        // Parse the whitespace from the string.
137        let (string, _) = Sanitizer::parse_whitespaces(string)?;
138        // Parse the default value from the string.
139        let (string, default) = Operand::parse(string)?;
140
141        // Parse the whitespace from the string.
142        let (string, _) = Sanitizer::parse_whitespaces(string)?;
143        // Parse the "into" keyword from the string.
144        let (string, _) = tag("into")(string)?;
145        // Parse the whitespace from the string.
146        let (string, _) = Sanitizer::parse_whitespaces(string)?;
147        // Parse the destination register from the string.
148        let (string, destination) = Register::parse(string)?;
149
150        // Parse the whitespace from the string.
151        let (string, _) = Sanitizer::parse_whitespaces(string)?;
152        // Parse the ";" from the string.
153        let (string, _) = tag(";")(string)?;
154
155        Ok((string, Self { mapping, operands: [key, default], destination }))
156    }
157}
158
159impl<N: Network> FromStr for GetOrUse<N> {
160    type Err = Error;
161
162    /// Parses a string into the command.
163    #[inline]
164    fn from_str(string: &str) -> Result<Self> {
165        match Self::parse(string) {
166            Ok((remainder, object)) => {
167                // Ensure the remainder is empty.
168                ensure!(remainder.is_empty(), "Failed to parse string. Found invalid character in: \"{remainder}\"");
169                // Return the object.
170                Ok(object)
171            }
172            Err(error) => bail!("Failed to parse string. {error}"),
173        }
174    }
175}
176
177impl<N: Network> Debug for GetOrUse<N> {
178    /// Prints the command as a string.
179    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
180        Display::fmt(self, f)
181    }
182}
183
184impl<N: Network> Display for GetOrUse<N> {
185    /// Prints the command to a string.
186    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
187        // Print the command.
188        write!(f, "{} ", Self::opcode())?;
189        // Print the mapping and key operand.
190        write!(f, "{}[{}] {} into ", self.mapping, self.key(), self.default())?;
191        // Print the destination register.
192        write!(f, "{};", self.destination)
193    }
194}
195
196impl<N: Network> FromBytes for GetOrUse<N> {
197    /// Reads the command from a buffer.
198    fn read_le<R: Read>(mut reader: R) -> IoResult<Self> {
199        // Read the mapping name.
200        let mapping = CallOperator::read_le(&mut reader)?;
201        // Read the key operand.
202        let key = Operand::read_le(&mut reader)?;
203        // Read the default value.
204        let default = Operand::read_le(&mut reader)?;
205        // Read the destination register.
206        let destination = Register::read_le(&mut reader)?;
207        // Return the command.
208        Ok(Self { mapping, operands: [key, default], destination })
209    }
210}
211
212impl<N: Network> ToBytes for GetOrUse<N> {
213    /// Writes the operation to a buffer.
214    fn write_le<W: Write>(&self, mut writer: W) -> IoResult<()> {
215        // Write the mapping name.
216        self.mapping.write_le(&mut writer)?;
217        // Write the key operand.
218        self.key().write_le(&mut writer)?;
219        // Write the default value.
220        self.default().write_le(&mut writer)?;
221        // Write the destination register.
222        self.destination.write_le(&mut writer)
223    }
224}
225
226#[cfg(test)]
227mod tests {
228    use super::*;
229    use console::{network::MainnetV0, program::Register};
230
231    type CurrentNetwork = MainnetV0;
232
233    #[test]
234    fn test_parse() {
235        let (string, get_or_use) = GetOrUse::<CurrentNetwork>::parse("get.or_use account[r0] r1 into r2;").unwrap();
236        assert!(string.is_empty(), "Parser did not consume all of the string: '{string}'");
237        assert_eq!(get_or_use.mapping, CallOperator::from_str("account").unwrap());
238        assert_eq!(get_or_use.operands().len(), 2, "The number of operands is incorrect");
239        assert_eq!(get_or_use.key(), &Operand::Register(Register::Locator(0)), "The first operand is incorrect");
240        assert_eq!(get_or_use.default(), &Operand::Register(Register::Locator(1)), "The second operand is incorrect");
241        assert_eq!(get_or_use.destination, Register::Locator(2), "The second operand is incorrect");
242
243        let (string, get_or_use) =
244            GetOrUse::<CurrentNetwork>::parse("get.or_use token.aleo/balances[r0] r1 into r2;").unwrap();
245        assert!(string.is_empty(), "Parser did not consume all of the string: '{string}'");
246        assert_eq!(get_or_use.mapping, CallOperator::from_str("token.aleo/balances").unwrap());
247        assert_eq!(get_or_use.operands().len(), 2, "The number of operands is incorrect");
248        assert_eq!(get_or_use.key(), &Operand::Register(Register::Locator(0)), "The first operand is incorrect");
249        assert_eq!(get_or_use.default(), &Operand::Register(Register::Locator(1)), "The second operand is incorrect");
250        assert_eq!(get_or_use.destination, Register::Locator(2), "The second operand is incorrect");
251    }
252
253    #[test]
254    fn test_from_bytes() {
255        let (string, get_or_use) = GetOrUse::<CurrentNetwork>::parse("get.or_use account[r0] r1 into r2;").unwrap();
256        assert!(string.is_empty());
257        let bytes_le = get_or_use.to_bytes_le().unwrap();
258        let result = GetOrUse::<CurrentNetwork>::from_bytes_le(&bytes_le[..]);
259        assert!(result.is_ok());
260    }
261}
snarkvm_synthesizer_program/logic/command/get_or_use.rs

snarkvm_synthesizer_program/logic/command/
get_or_use.rs
