fast-check
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Property based testing framework for JavaScript (like QuickCheck)
153 lines (152 loc) • 7.48 kB
JavaScript
import { safeCharCodeAt, safeEvery, safeJoin, safeSubstring, Error, safeIndexOf, safeMap } from '../utils/globals.js';
import { stringify } from '../utils/stringify.js';
import { addMissingDotStar } from './_internals/helpers/SanitizeRegexAst.js';
import { tokenizeRegex } from './_internals/helpers/TokenizeRegex.js';
import { char } from './char.js';
import { constant } from './constant.js';
import { constantFrom } from './constantFrom.js';
import { integer } from './integer.js';
import { oneof } from './oneof.js';
import { stringOf } from './stringOf.js';
import { tuple } from './tuple.js';
const safeStringFromCodePoint = String.fromCodePoint;
const wordChars = [...'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_'];
const digitChars = [...'0123456789'];
const spaceChars = [...' \t\r\n\v\f'];
const newLineChars = [...'\r\n'];
const terminatorChars = [...'\x1E\x15'];
const newLineAndTerminatorChars = [...newLineChars, ...terminatorChars];
const defaultChar = char();
function raiseUnsupportedASTNode(astNode) {
return new Error(`Unsupported AST node! Received: ${stringify(astNode)}`);
}
function toMatchingArbitrary(astNode, constraints, flags) {
switch (astNode.type) {
case 'Char': {
if (astNode.kind === 'meta') {
switch (astNode.value) {
case '\\w': {
return constantFrom(...wordChars);
}
case '\\W': {
return defaultChar.filter((c) => safeIndexOf(wordChars, c) === -1);
}
case '\\d': {
return constantFrom(...digitChars);
}
case '\\D': {
return defaultChar.filter((c) => safeIndexOf(digitChars, c) === -1);
}
case '\\s': {
return constantFrom(...spaceChars);
}
case '\\S': {
return defaultChar.filter((c) => safeIndexOf(spaceChars, c) === -1);
}
case '\\b':
case '\\B': {
throw new Error(`Meta character ${astNode.value} not implemented yet!`);
}
case '.': {
const forbiddenChars = flags.dotAll ? terminatorChars : newLineAndTerminatorChars;
return defaultChar.filter((c) => safeIndexOf(forbiddenChars, c) === -1);
}
}
}
if (astNode.symbol === undefined) {
throw new Error(`Unexpected undefined symbol received for non-meta Char! Received: ${stringify(astNode)}`);
}
return constant(astNode.symbol);
}
case 'Repetition': {
const node = toMatchingArbitrary(astNode.expression, constraints, flags);
switch (astNode.quantifier.kind) {
case '*': {
return stringOf(node, constraints);
}
case '+': {
return stringOf(node, Object.assign(Object.assign({}, constraints), { minLength: 1 }));
}
case '?': {
return stringOf(node, Object.assign(Object.assign({}, constraints), { minLength: 0, maxLength: 1 }));
}
case 'Range': {
return stringOf(node, Object.assign(Object.assign({}, constraints), { minLength: astNode.quantifier.from, maxLength: astNode.quantifier.to }));
}
default: {
throw raiseUnsupportedASTNode(astNode.quantifier);
}
}
}
case 'Quantifier': {
throw new Error(`Wrongly defined AST tree, Quantifier nodes not supposed to be scanned!`);
}
case 'Alternative': {
return tuple(...safeMap(astNode.expressions, (n) => toMatchingArbitrary(n, constraints, flags))).map((vs) => safeJoin(vs, ''));
}
case 'CharacterClass':
if (astNode.negative) {
const childrenArbitraries = safeMap(astNode.expressions, (n) => toMatchingArbitrary(n, constraints, flags));
return defaultChar.filter((c) => safeEvery(childrenArbitraries, (arb) => !arb.canShrinkWithoutContext(c)));
}
return oneof(...safeMap(astNode.expressions, (n) => toMatchingArbitrary(n, constraints, flags)));
case 'ClassRange': {
const min = astNode.from.codePoint;
const max = astNode.to.codePoint;
return integer({ min, max }).map((n) => safeStringFromCodePoint(n), (c) => {
if (typeof c !== 'string')
throw new Error('Invalid type');
if ([...c].length !== 1)
throw new Error('Invalid length');
return safeCharCodeAt(c, 0);
});
}
case 'Group': {
return toMatchingArbitrary(astNode.expression, constraints, flags);
}
case 'Disjunction': {
const left = astNode.left !== null ? toMatchingArbitrary(astNode.left, constraints, flags) : constant('');
const right = astNode.right !== null ? toMatchingArbitrary(astNode.right, constraints, flags) : constant('');
return oneof(left, right);
}
case 'Assertion': {
if (astNode.kind === '^' || astNode.kind === '$') {
if (flags.multiline) {
if (astNode.kind === '^') {
return oneof(constant(''), tuple(stringOf(defaultChar), constantFrom(...newLineChars)).map((t) => `${t[0]}${t[1]}`, (value) => {
if (typeof value !== 'string' || value.length === 0)
throw new Error('Invalid type');
return [safeSubstring(value, 0, value.length - 1), value[value.length - 1]];
}));
}
else {
return oneof(constant(''), tuple(constantFrom(...newLineChars), stringOf(defaultChar)).map((t) => `${t[0]}${t[1]}`, (value) => {
if (typeof value !== 'string' || value.length === 0)
throw new Error('Invalid type');
return [value[0], safeSubstring(value, 1)];
}));
}
}
return constant('');
}
throw new Error(`Assertions of kind ${astNode.kind} not implemented yet!`);
}
case 'Backreference': {
throw new Error(`Backreference nodes not implemented yet!`);
}
default: {
throw raiseUnsupportedASTNode(astNode);
}
}
}
export function stringMatching(regex, constraints = {}) {
for (const flag of regex.flags) {
if (flag !== 'd' && flag !== 'g' && flag !== 'm' && flag !== 's' && flag !== 'u') {
throw new Error(`Unable to use "stringMatching" against a regex using the flag ${flag}`);
}
}
const sanitizedConstraints = { size: constraints.size };
const flags = { multiline: regex.multiline, dotAll: regex.dotAll };
const regexRootToken = addMissingDotStar(tokenizeRegex(regex));
return toMatchingArbitrary(regexRootToken, sanitizedConstraints, flags);
}