Module fuzzcheck::mutators::grammar

Available on crate feature grammar_mutator only.

Expand description

Grammar-based mutators and related utilties.

This module provides a grammar-based impl Mutator<AST> which generates an abstract syntax tree satisfying a grammar, created through grammar_based_ast_mutator. The resulting mutator can be transformed into a Mutator<(AST, String)>, where the second element of the tuple is the string corresponding to the abstract syntax tree, by calling .with_string().

To specify a grammar, you should use the following functions:

regex to create a grammar from a regular expression (only supported on crate feature regex_grammar)
literal for a grammar that matches a single character
literal_ranges for a grammar matching a single character within a specified ranges
literal_ranges for a grammar matching a single character within any of multiple ranges
alternation for a grammar matching any of a list of grammar rules
concatenation matching multiple grammar rules one after the other
repetition matching a grammar rule multiple times
recursive and recurse to create recursive grammar rules Examples:

use fuzzcheck::mutators::grammar::{alternation, concatenation, literal, literal_range, recurse, recursive, regex, repetition};
let rule = repetition(
    concatenation([
        alternation([
            regex("hello[0-9]"),
            regex("world[0-9]?")
        ]),
        literal(' '),
    ]),
    1..5
);
/* “rule” matches/generates:
    hello1
    hello2 hello6 world
    world8 hello5 world7 world world
    ...
*/
let rule = recursive(|rule| {
    alternation([
        concatenation([
            regex(r"\(|\["),
            recurse(rule),
            regex(r"\)|\]"),
        ]),
        literal_range('a' ..= 'z')
    ])
});
/* rule matches/generates:
    (([a)))
    (([[d))])
    z
    ...
 */

Structs

ASTMutator

A mutator created by grammar_based_ast_mutator

Enums

AST

An abstract syntax tree.

Grammar

A grammar which can be used for fuzzing.

Functions

alternation

concatenation

grammar_based_ast_mutator

regexregex_grammar