/
eval.js
149 lines (119 loc) · 3.95 KB
/
eval.js
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var test = require('tape');
var evaluate = require('../');
var parse = require('esprima').parse;
test('resolved', function (t) {
t.plan(1);
var src = '[1,2,3+4*10+(n||6),foo(3+5),obj[""+"x"].y]';
var ast = parse(src).body[0].expression;
var res = evaluate(ast, {
n: false,
foo: function (x) { return x * 100 },
obj: { x: { y: 555 } }
});
t.deepEqual(res, [ 1, 2, 49, 800, 555 ]);
});
test('unresolved', function (t) {
t.plan(1);
var src = '[1,2,3+4*10*z+n,foo(3+5),obj[""+"x"].y]';
var ast = parse(src).body[0].expression;
var res = evaluate(ast, {
n: 6,
foo: function (x) { return x * 100 },
obj: { x: { y: 555 } }
});
t.equal(res, undefined);
});
test('boolean', function (t) {
t.plan(1);
var src = '[ 1===2+3-16/4, [2]==2, [2]!==2, [2]!==[2] ]';
var ast = parse(src).body[0].expression;
t.deepEqual(evaluate(ast), [ true, true, true, true ]);
});
test('array methods', function(t) {
t.plan(1);
var src = '[1, 2, 3].map(function(n) { return n * 2 })';
var ast = parse(src).body[0].expression;
t.deepEqual(evaluate(ast), [2, 4, 6]);
});
test('array methods with vars', function(t) {
t.plan(1);
var src = '[1, 2, 3].map(function(n) { return n * x })';
var ast = parse(src).body[0].expression;
t.deepEqual(evaluate(ast, {x: 2}), [2, 4, 6]);
});
test('evaluate this', function(t) {
t.plan(1);
var src = 'this.x + this.y.z';
var ast = parse(src).body[0].expression;
var res = evaluate(ast, {
'this': { x: 1, y: { z: 100 } }
});
t.equal(res, 101);
});
test('FunctionExpression unresolved', function(t) {
t.plan(1);
var src = '(function(){console.log("Not Good")})';
var ast = parse(src).body[0].expression;
var res = evaluate(ast, {});
t.equal(res, undefined);
});
test('MemberExpressions from Functions unresolved', function(t) {
t.plan(1);
var src = '(function () {}).constructor';
var ast = parse(src).body[0].expression;
var res = evaluate(ast, {});
t.equal(res, undefined);
});
test('disallow accessing constructor or __proto__', function (t) {
t.plan(4)
var someValue = {};
var src = 'object.constructor';
var ast = parse(src).body[0].expression;
var res = evaluate(ast, { vars: { object: someValue } });
t.equal(res, undefined);
var src = 'object["constructor"]';
var ast = parse(src).body[0].expression;
var res = evaluate(ast, { vars: { object: someValue } });
t.equal(res, undefined);
var src = 'object.__proto__';
var ast = parse(src).body[0].expression;
var res = evaluate(ast, { vars: { object: someValue } });
t.equal(res, undefined);
var src = 'object["__pro"+"t\x6f__"]';
var ast = parse(src).body[0].expression;
var res = evaluate(ast, { vars: { object: someValue } });
t.equal(res, undefined);
});
test('constructor at runtime only', function(t) {
t.plan(2)
var src = '(function myTag(y){return ""[!y?"__proto__":"constructor"][y]})("constructor")("console.log(process.env)")()'
var ast = parse(src).body[0].expression;
var res = evaluate(ast);
t.equal(res, undefined);
var src = '(function(prop) { return {}[prop ? "benign" : "constructor"][prop] })("constructor")("alert(1)")()'
var ast = parse(src).body[0].expression;
var res = evaluate(ast);
t.equal(res, undefined);
});
test('short circuit evaluation AND', function(t) {
t.plan(1);
var variables = {
value: null
};
var src = 'value && value.func()';
var ast = parse(src).body[0].expression;
var res = evaluate(ast, variables);
t.equals(res, null);
})
test('short circuit evaluation OR', function(t) {
t.plan(1);
var fnInvoked = false;
var variables = {
value: true,
fn: function() { fnInvoked = true}
};
var src = 'value || fn()';
var ast = parse(src).body[0].expression;
evaluate(ast, variables);
t.equals(fnInvoked, false);
})