v5

node_modules/@babel/traverse/lib/path/evaluation.js

@@ -0,0 +1,404 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.evaluateTruthy = evaluateTruthy;
+exports.evaluate = evaluate;
+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;
+  const {
+    node
+  } = path;
+
+  if (path.isSequenceExpression()) {
+    const exprs = path.get("expressions");
+    return evaluateCached(exprs[exprs.length - 1], state);
+  }
+
+  if (path.isStringLiteral() || path.isNumericLiteral() || path.isBooleanLiteral()) {
+    return node.value;
+  }
+
+  if (path.isNullLiteral()) {
+    return null;
+  }
+
+  if (path.isTemplateLiteral()) {
+    return evaluateQuasis(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, true) && property.isIdentifier && property.node.name === "raw") {
+      return evaluateQuasis(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: 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(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 && binding.hasValue) {
+      return binding.value;
+    } else {
+      if (node.name === "undefined") {
+        return binding ? deopt(binding.path, state) : undefined;
+      } else if (node.name === "Infinity") {
+        return binding ? deopt(binding.path, state) : Infinity;
+      } else if (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 (node.operator === "void") {
+      return undefined;
+    }
+
+    const argument = path.get("argument");
+
+    if (node.operator === "typeof" && (argument.isFunction() || argument.isClass())) {
+      return "function";
+    }
+
+    const arg = evaluateCached(argument, state);
+    if (!state.confident) return;
+
+    switch (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(elem, 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(keyPath, 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(valuePath, 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 (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 (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, true) && VALID_CALLEES.indexOf(callee.node.name) >= 0) {
+      func = global[node.callee.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
+  };
+}