packages/meteor-jasmine/src/lib/parseStack.js
/* globals parseStack: true */
parseStack = {};
// Given an Error (eg, 'new Error'), return the stack associated with
// that error as an array. More recently called functions appear first
// and each element is an object with keys:
// - file: filename as it appears in the stack
// - line: 1-indexed line number in file, as a Number
// - column: 1-indexed column in line, as a Number
// - func: name of the function in the frame (maybe null)
//
// Accomplishes this by parsing the text representation of the stack
// with regular expressions. Unlikely to work anywhere but v8.
//
// If a function on the stack has been marked with mark(), don't
// return anything past that function. We call this the "user portion"
// of the stack.
parseStack.parse = function (err) {
var frames = err.stack.split('\n');
frames.shift(); // at least the first line is the exception
var stop = false;
var ret = [];
_.each(frames, function (frame) {
if (stop)
return;
var m;
if (m =
frame.match(/^\s*at\s*((new )?.+?)\s*(\[as\s*([^\]]*)\]\s*)?\((.*?)(:(\d+))?(:(\d+))?\)\s*$/)) {
// https://code.google.com/p/v8/wiki/JavaScriptStackTraceApi
// " at My.Function (/path/to/myfile.js:532:39)"
// " at Array.forEach (native)"
// " at new My.Class (file.js:1:2)"
// " at [object Object].main.registerCommand.name [as func] (meteor/tools/commands.js:1225:19)"
// " at __top_mark__ [as matchErr] (meteor/tools/parse-stack.js:82:14)"
//
// In that last example, it is not at all clear to me what the
// 'as' stanza refers to, but it is in m[3] if you find a use for it.
if (m[1].match(/(?:^|\.)__top_mark__$/)) {
// m[1] could be Object.__top_mark__ or something like that
// depending on where exactly you put the function returned by
// markTop
ret = [];
return;
}
if (m[1].match(/(?:^|\.)__bottom_mark__$/)) {
stop = true;
return;
}
ret.push({
func: m[1],
file: m[5],
line: m[7] ? +m[7] : undefined,
column: m[9] ? +m[9] : undefined
});
} else if (m = frame.match(/^\s*at\s+(.+?)(:(\d+))?(:(\d+))?\s*$/)) {
// " at /path/to/myfile.js:532:39"
ret.push({
file: m[1],
line: m[3] ? +m[3] : undefined,
column: m[5] ? +m[5] : undefined
});
} else if (m = frame.match(/^\s*-\s*-\s*-\s*-\s*-\s*$/)) {
// " - - - - -"
// This is something added when you throw an Error through a future. The
// stack above the dashes is the stack of the 'wait' call; the stack below
// is the stack inside the fiber where the Error is originally
// constructed. Taking just the former seems good for now, but in the
// future we may want to sew them together (possibly in the opposite
// order?)
stop = true;
}
});
return ret;
};
// Decorator. Mark the point at which a stack trace returned by
// parse() should stop: no frames earlier than this point will be
// included in the parsed stack. Confusingly, in the argot of the
// times, you'd say that frames "higher up" than this or "above" this
// will not be returned, but you'd also say that those frames are "at
// the bottom of the stack". Frames below the bottom are the outer
// context of the framework running the user's code.
parseStack.markBottom = function (f) {
return function __bottom_mark__ () {
return f.apply(this, arguments);
};
};
// Decorator. Mark the point at which a stack trace returned by
// parse() should begin: no frames later than this point will be
// included in the parsed stack. The opposite of markBottom().
// Frames above the top are helper functions defined by the
// framework and executed by user code whose internal behavior
// should not be exposed.
parseStack.markTop = function (f) {
return function __top_mark__ () {
return f.apply(this, arguments);
};
};