forked from M3-Academy/challenge-algorithms-v2.0
417 lines
9.3 KiB
JavaScript
417 lines
9.3 KiB
JavaScript
"use strict";
|
|
|
|
Object.defineProperty(exports, "__esModule", {
|
|
value: true
|
|
});
|
|
exports.evaluate = evaluate;
|
|
exports.evaluateTruthy = evaluateTruthy;
|
|
const VALID_CALLEES = ["String", "Number", "Math"];
|
|
const INVALID_METHODS = ["random"];
|
|
|
|
function isValidCallee(val) {
|
|
return VALID_CALLEES.includes(val);
|
|
}
|
|
|
|
function isInvalidMethod(val) {
|
|
return INVALID_METHODS.includes(val);
|
|
}
|
|
|
|
function evaluateTruthy() {
|
|
const res = this.evaluate();
|
|
if (res.confident) return !!res.value;
|
|
}
|
|
|
|
function deopt(path, state) {
|
|
if (!state.confident) return;
|
|
state.deoptPath = path;
|
|
state.confident = false;
|
|
}
|
|
|
|
function evaluateCached(path, state) {
|
|
const {
|
|
node
|
|
} = path;
|
|
const {
|
|
seen
|
|
} = state;
|
|
|
|
if (seen.has(node)) {
|
|
const existing = seen.get(node);
|
|
|
|
if (existing.resolved) {
|
|
return existing.value;
|
|
} else {
|
|
deopt(path, state);
|
|
return;
|
|
}
|
|
} else {
|
|
const item = {
|
|
resolved: false
|
|
};
|
|
seen.set(node, item);
|
|
|
|
const val = _evaluate(path, state);
|
|
|
|
if (state.confident) {
|
|
item.resolved = true;
|
|
item.value = val;
|
|
}
|
|
|
|
return val;
|
|
}
|
|
}
|
|
|
|
function _evaluate(path, state) {
|
|
if (!state.confident) return;
|
|
|
|
if (path.isSequenceExpression()) {
|
|
const exprs = path.get("expressions");
|
|
return evaluateCached(exprs[exprs.length - 1], state);
|
|
}
|
|
|
|
if (path.isStringLiteral() || path.isNumericLiteral() || path.isBooleanLiteral()) {
|
|
return path.node.value;
|
|
}
|
|
|
|
if (path.isNullLiteral()) {
|
|
return null;
|
|
}
|
|
|
|
if (path.isTemplateLiteral()) {
|
|
return evaluateQuasis(path, path.node.quasis, state);
|
|
}
|
|
|
|
if (path.isTaggedTemplateExpression() && path.get("tag").isMemberExpression()) {
|
|
const object = path.get("tag.object");
|
|
const {
|
|
node: {
|
|
name
|
|
}
|
|
} = object;
|
|
const property = path.get("tag.property");
|
|
|
|
if (object.isIdentifier() && name === "String" && !path.scope.getBinding(name) && property.isIdentifier() && property.node.name === "raw") {
|
|
return evaluateQuasis(path, path.node.quasi.quasis, state, true);
|
|
}
|
|
}
|
|
|
|
if (path.isConditionalExpression()) {
|
|
const testResult = evaluateCached(path.get("test"), state);
|
|
if (!state.confident) return;
|
|
|
|
if (testResult) {
|
|
return evaluateCached(path.get("consequent"), state);
|
|
} else {
|
|
return evaluateCached(path.get("alternate"), state);
|
|
}
|
|
}
|
|
|
|
if (path.isExpressionWrapper()) {
|
|
return evaluateCached(path.get("expression"), state);
|
|
}
|
|
|
|
if (path.isMemberExpression() && !path.parentPath.isCallExpression({
|
|
callee: path.node
|
|
})) {
|
|
const property = path.get("property");
|
|
const object = path.get("object");
|
|
|
|
if (object.isLiteral() && property.isIdentifier()) {
|
|
const value = object.node.value;
|
|
const type = typeof value;
|
|
|
|
if (type === "number" || type === "string") {
|
|
return value[property.node.name];
|
|
}
|
|
}
|
|
}
|
|
|
|
if (path.isReferencedIdentifier()) {
|
|
const binding = path.scope.getBinding(path.node.name);
|
|
|
|
if (binding && binding.constantViolations.length > 0) {
|
|
return deopt(binding.path, state);
|
|
}
|
|
|
|
if (binding && path.node.start < binding.path.node.end) {
|
|
return deopt(binding.path, state);
|
|
}
|
|
|
|
if (binding != null && binding.hasValue) {
|
|
return binding.value;
|
|
} else {
|
|
if (path.node.name === "undefined") {
|
|
return binding ? deopt(binding.path, state) : undefined;
|
|
} else if (path.node.name === "Infinity") {
|
|
return binding ? deopt(binding.path, state) : Infinity;
|
|
} else if (path.node.name === "NaN") {
|
|
return binding ? deopt(binding.path, state) : NaN;
|
|
}
|
|
|
|
const resolved = path.resolve();
|
|
|
|
if (resolved === path) {
|
|
return deopt(path, state);
|
|
} else {
|
|
return evaluateCached(resolved, state);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (path.isUnaryExpression({
|
|
prefix: true
|
|
})) {
|
|
if (path.node.operator === "void") {
|
|
return undefined;
|
|
}
|
|
|
|
const argument = path.get("argument");
|
|
|
|
if (path.node.operator === "typeof" && (argument.isFunction() || argument.isClass())) {
|
|
return "function";
|
|
}
|
|
|
|
const arg = evaluateCached(argument, state);
|
|
if (!state.confident) return;
|
|
|
|
switch (path.node.operator) {
|
|
case "!":
|
|
return !arg;
|
|
|
|
case "+":
|
|
return +arg;
|
|
|
|
case "-":
|
|
return -arg;
|
|
|
|
case "~":
|
|
return ~arg;
|
|
|
|
case "typeof":
|
|
return typeof arg;
|
|
}
|
|
}
|
|
|
|
if (path.isArrayExpression()) {
|
|
const arr = [];
|
|
const elems = path.get("elements");
|
|
|
|
for (const elem of elems) {
|
|
const elemValue = elem.evaluate();
|
|
|
|
if (elemValue.confident) {
|
|
arr.push(elemValue.value);
|
|
} else {
|
|
return deopt(elemValue.deopt, state);
|
|
}
|
|
}
|
|
|
|
return arr;
|
|
}
|
|
|
|
if (path.isObjectExpression()) {
|
|
const obj = {};
|
|
const props = path.get("properties");
|
|
|
|
for (const prop of props) {
|
|
if (prop.isObjectMethod() || prop.isSpreadElement()) {
|
|
return deopt(prop, state);
|
|
}
|
|
|
|
const keyPath = prop.get("key");
|
|
let key;
|
|
|
|
if (prop.node.computed) {
|
|
key = keyPath.evaluate();
|
|
|
|
if (!key.confident) {
|
|
return deopt(key.deopt, state);
|
|
}
|
|
|
|
key = key.value;
|
|
} else if (keyPath.isIdentifier()) {
|
|
key = keyPath.node.name;
|
|
} else {
|
|
key = keyPath.node.value;
|
|
}
|
|
|
|
const valuePath = prop.get("value");
|
|
let value = valuePath.evaluate();
|
|
|
|
if (!value.confident) {
|
|
return deopt(value.deopt, state);
|
|
}
|
|
|
|
value = value.value;
|
|
obj[key] = value;
|
|
}
|
|
|
|
return obj;
|
|
}
|
|
|
|
if (path.isLogicalExpression()) {
|
|
const wasConfident = state.confident;
|
|
const left = evaluateCached(path.get("left"), state);
|
|
const leftConfident = state.confident;
|
|
state.confident = wasConfident;
|
|
const right = evaluateCached(path.get("right"), state);
|
|
const rightConfident = state.confident;
|
|
|
|
switch (path.node.operator) {
|
|
case "||":
|
|
state.confident = leftConfident && (!!left || rightConfident);
|
|
if (!state.confident) return;
|
|
return left || right;
|
|
|
|
case "&&":
|
|
state.confident = leftConfident && (!left || rightConfident);
|
|
if (!state.confident) return;
|
|
return left && right;
|
|
|
|
case "??":
|
|
state.confident = leftConfident && (left != null || rightConfident);
|
|
if (!state.confident) return;
|
|
return left != null ? left : right;
|
|
}
|
|
}
|
|
|
|
if (path.isBinaryExpression()) {
|
|
const left = evaluateCached(path.get("left"), state);
|
|
if (!state.confident) return;
|
|
const right = evaluateCached(path.get("right"), state);
|
|
if (!state.confident) return;
|
|
|
|
switch (path.node.operator) {
|
|
case "-":
|
|
return left - right;
|
|
|
|
case "+":
|
|
return left + right;
|
|
|
|
case "/":
|
|
return left / right;
|
|
|
|
case "*":
|
|
return left * right;
|
|
|
|
case "%":
|
|
return left % right;
|
|
|
|
case "**":
|
|
return Math.pow(left, right);
|
|
|
|
case "<":
|
|
return left < right;
|
|
|
|
case ">":
|
|
return left > right;
|
|
|
|
case "<=":
|
|
return left <= right;
|
|
|
|
case ">=":
|
|
return left >= right;
|
|
|
|
case "==":
|
|
return left == right;
|
|
|
|
case "!=":
|
|
return left != right;
|
|
|
|
case "===":
|
|
return left === right;
|
|
|
|
case "!==":
|
|
return left !== right;
|
|
|
|
case "|":
|
|
return left | right;
|
|
|
|
case "&":
|
|
return left & right;
|
|
|
|
case "^":
|
|
return left ^ right;
|
|
|
|
case "<<":
|
|
return left << right;
|
|
|
|
case ">>":
|
|
return left >> right;
|
|
|
|
case ">>>":
|
|
return left >>> right;
|
|
}
|
|
}
|
|
|
|
if (path.isCallExpression()) {
|
|
const callee = path.get("callee");
|
|
let context;
|
|
let func;
|
|
|
|
if (callee.isIdentifier() && !path.scope.getBinding(callee.node.name) && isValidCallee(callee.node.name)) {
|
|
func = global[callee.node.name];
|
|
}
|
|
|
|
if (callee.isMemberExpression()) {
|
|
const object = callee.get("object");
|
|
const property = callee.get("property");
|
|
|
|
if (object.isIdentifier() && property.isIdentifier() && isValidCallee(object.node.name) && !isInvalidMethod(property.node.name)) {
|
|
context = global[object.node.name];
|
|
func = context[property.node.name];
|
|
}
|
|
|
|
if (object.isLiteral() && property.isIdentifier()) {
|
|
const type = typeof object.node.value;
|
|
|
|
if (type === "string" || type === "number") {
|
|
context = object.node.value;
|
|
func = context[property.node.name];
|
|
}
|
|
}
|
|
}
|
|
|
|
if (func) {
|
|
const args = path.get("arguments").map(arg => evaluateCached(arg, state));
|
|
if (!state.confident) return;
|
|
return func.apply(context, args);
|
|
}
|
|
}
|
|
|
|
deopt(path, state);
|
|
}
|
|
|
|
function evaluateQuasis(path, quasis, state, raw = false) {
|
|
let str = "";
|
|
let i = 0;
|
|
const exprs = path.get("expressions");
|
|
|
|
for (const elem of quasis) {
|
|
if (!state.confident) break;
|
|
str += raw ? elem.value.raw : elem.value.cooked;
|
|
const expr = exprs[i++];
|
|
if (expr) str += String(evaluateCached(expr, state));
|
|
}
|
|
|
|
if (!state.confident) return;
|
|
return str;
|
|
}
|
|
|
|
function evaluate() {
|
|
const state = {
|
|
confident: true,
|
|
deoptPath: null,
|
|
seen: new Map()
|
|
};
|
|
let value = evaluateCached(this, state);
|
|
if (!state.confident) value = undefined;
|
|
return {
|
|
confident: state.confident,
|
|
deopt: state.deoptPath,
|
|
value: value
|
|
};
|
|
}
|
|
|
|
//# sourceMappingURL=evaluation.js.map
|