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-rw-r--r--node_modules/@babel/traverse/lib/path/evaluation.js401
1 files changed, 401 insertions, 0 deletions
diff --git a/node_modules/@babel/traverse/lib/path/evaluation.js b/node_modules/@babel/traverse/lib/path/evaluation.js
new file mode 100644
index 0000000..abbbe05
--- /dev/null
+++ b/node_modules/@babel/traverse/lib/path/evaluation.js
@@ -0,0 +1,401 @@
+"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 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 = keyPath;
+
+ if (prop.node.computed) {
+ key = key.evaluate();
+
+ if (!key.confident) {
+ return deopt(key.deopt, state);
+ }
+
+ key = key.value;
+ } else if (key.isIdentifier()) {
+ key = key.node.name;
+ } else {
+ key = key.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;
+ }
+ }
+
+ 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) && VALID_CALLEES.indexOf(callee.node.name) >= 0) {
+ func = global[callee.node.name];
+ }
+
+ if (callee.isMemberExpression()) {
+ const object = callee.get("object");
+ const property = callee.get("property");
+
+ if (object.isIdentifier() && property.isIdentifier() && VALID_CALLEES.indexOf(object.node.name) >= 0 && INVALID_METHODS.indexOf(property.node.name) < 0) {
+ 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
+ };
+} \ No newline at end of file