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/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/*---
defines: [testLenientAndStrict, parsesSuccessfully, parseRaisesException, returns]
allow_unused: True
---*/
(function(global) {
/*
* Return true if both of these return true:
* - LENIENT_PRED applied to CODE
* - STRICT_PRED applied to CODE with a use strict directive added to the front
*
* Run STRICT_PRED first, for testing code that affects the global environment
* in loose mode, but fails in strict mode.
*/
global.testLenientAndStrict = function testLenientAndStrict(code, lenient_pred, strict_pred) {
return (strict_pred("'use strict'; " + code) &&
lenient_pred(code));
}
/*
* parsesSuccessfully(CODE) returns true if CODE parses as function
* code without an error.
*/
global.parsesSuccessfully = function parsesSuccessfully(code) {
try {
Function(code);
return true;
} catch (exception) {
return false;
}
};
/*
* parseRaisesException(EXCEPTION)(CODE) returns true if parsing CODE
* as function code raises EXCEPTION.
*/
global.parseRaisesException = function parseRaisesException(exception) {
return function (code) {
try {
Function(code);
return false;
} catch (actual) {
return exception.prototype.isPrototypeOf(actual);
}
};
};
/*
* returns(VALUE)(CODE) returns true if evaluating CODE (as eval code)
* completes normally (rather than throwing an exception), yielding a value
* strictly equal to VALUE.
*/
global.returns = function returns(value) {
return function(code) {
try {
return eval(code) === value;
} catch (exception) {
return false;
}
}
}
})(this);