blob: 10d964b965b6ff83e07d79c8fb7d0bd410c2d51d [file] [log] [blame]
//
// Eyes.js - a customizable value inspector for Node.js
//
// usage:
//
// var inspect = require('eyes').inspector({styles: {all: 'magenta'}});
// inspect(something); // inspect with the settings passed to `inspector`
//
// or
//
// var eyes = require('eyes');
// eyes.inspect(something); // inspect with the default settings
//
var eyes = exports,
stack = [];
eyes.defaults = {
styles: { // Styles applied to stdout
all: 'cyan', // Overall style applied to everything
label: 'underline', // Inspection labels, like 'array' in `array: [1, 2, 3]`
other: 'inverted', // Objects which don't have a literal representation, such as functions
key: 'bold', // The keys in object literals, like 'a' in `{a: 1}`
special: 'grey', // null, undefined...
string: 'green',
number: 'magenta',
bool: 'blue', // true false
regexp: 'green', // /\d+/
},
pretty: true, // Indent object literals
hideFunctions: false,
showHidden: false,
stream: process.stdout,
maxLength: 2048 // Truncate output if longer
};
// Return a curried inspect() function, with the `options` argument filled in.
eyes.inspector = function (options) {
var that = this;
return function (obj, label, opts) {
return that.inspect.call(that, obj, label,
merge(options || {}, opts || {}));
};
};
// If we have a `stream` defined, use it to print a styled string,
// if not, we just return the stringified object.
eyes.inspect = function (obj, label, options) {
options = merge(this.defaults, options || {});
if (options.stream) {
return this.print(stringify(obj, options), label, options);
} else {
return stringify(obj, options) + (options.styles ? '\033[39m' : '');
}
};
// Output using the 'stream', and an optional label
// Loop through `str`, and truncate it after `options.maxLength` has been reached.
// Because escape sequences are, at this point embeded within
// the output string, we can't measure the length of the string
// in a useful way, without separating what is an escape sequence,
// versus a printable character (`c`). So we resort to counting the
// length manually.
eyes.print = function (str, label, options) {
for (var c = 0, i = 0; i < str.length; i++) {
if (str.charAt(i) === '\033') { i += 4 } // `4` because '\033[25m'.length + 1 == 5
else if (c === options.maxLength) {
str = str.slice(0, i - 1) + '…';
break;
} else { c++ }
}
return options.stream.write.call(options.stream, (label ?
this.stylize(label, options.styles.label, options.styles) + ': ' : '') +
this.stylize(str, options.styles.all, options.styles) + '\033[0m' + "\n");
};
// Apply a style to a string, eventually,
// I'd like this to support passing multiple
// styles.
eyes.stylize = function (str, style, styles) {
var codes = {
'bold' : [1, 22],
'underline' : [4, 24],
'inverse' : [7, 27],
'cyan' : [36, 39],
'magenta' : [35, 39],
'blue' : [34, 39],
'yellow' : [33, 39],
'green' : [32, 39],
'red' : [31, 39],
'grey' : [90, 39]
}, endCode;
if (style && codes[style]) {
endCode = (codes[style][1] === 39 && styles.all) ? codes[styles.all][0]
: codes[style][1];
return '\033[' + codes[style][0] + 'm' + str +
'\033[' + endCode + 'm';
} else { return str }
};
// Convert any object to a string, ready for output.
// When an 'array' or an 'object' are encountered, they are
// passed to specialized functions, which can then recursively call
// stringify().
function stringify(obj, options) {
var that = this, stylize = function (str, style) {
return eyes.stylize(str, options.styles[style], options.styles)
}, index, result;
if ((index = stack.indexOf(obj)) !== -1) {
return stylize(new(Array)(stack.length - index + 1).join('.'), 'special');
}
stack.push(obj);
result = (function (obj) {
switch (typeOf(obj)) {
case "string" : obj = stringifyString(obj.indexOf("'") === -1 ? "'" + obj + "'"
: '"' + obj + '"');
return stylize(obj, 'string');
case "regexp" : return stylize('/' + obj.source + '/', 'regexp');
case "number" : return stylize(obj + '', 'number');
case "function" : return options.stream ? stylize("Function", 'other') : '[Function]';
case "null" : return stylize("null", 'special');
case "undefined": return stylize("undefined", 'special');
case "boolean" : return stylize(obj + '', 'bool');
case "date" : return stylize(obj.toUTCString());
case "array" : return stringifyArray(obj, options, stack.length);
case "object" : return stringifyObject(obj, options, stack.length);
}
})(obj);
stack.pop();
return result;
};
// Escape invisible characters in a string
function stringifyString (str, options) {
return str.replace(/\\/g, '\\\\')
.replace(/\n/g, '\\n')
.replace(/[\u0001-\u001F]/g, function (match) {
return '\\0' + match[0].charCodeAt(0).toString(8);
});
}
// Convert an array to a string, such as [1, 2, 3].
// This function calls stringify() for each of the elements
// in the array.
function stringifyArray(ary, options, level) {
var out = [];
var pretty = options.pretty && (ary.length > 4 || ary.some(function (o) {
return (o !== null && typeof(o) === 'object' && Object.keys(o).length > 0) ||
(Array.isArray(o) && o.length > 0);
}));
var ws = pretty ? '\n' + new(Array)(level * 4 + 1).join(' ') : ' ';
for (var i = 0; i < ary.length; i++) {
out.push(stringify(ary[i], options));
}
if (out.length === 0) {
return '[]';
} else {
return '[' + ws
+ out.join(',' + (pretty ? ws : ' '))
+ (pretty ? ws.slice(0, -4) : ws) +
']';
}
};
// Convert an object to a string, such as {a: 1}.
// This function calls stringify() for each of its values,
// and does not output functions or prototype values.
function stringifyObject(obj, options, level) {
var out = [];
var pretty = options.pretty && (Object.keys(obj).length > 2 ||
Object.keys(obj).some(function (k) { return typeof(obj[k]) === 'object' }));
var ws = pretty ? '\n' + new(Array)(level * 4 + 1).join(' ') : ' ';
var keys = options.showHidden ? Object.keys(obj) : Object.getOwnPropertyNames(obj);
keys.forEach(function (k) {
if (Object.prototype.hasOwnProperty.call(obj, k)
&& !(obj[k] instanceof Function && options.hideFunctions)) {
out.push(eyes.stylize(k, options.styles.key, options.styles) + ': ' +
stringify(obj[k], options));
}
});
if (out.length === 0) {
return '{}';
} else {
return "{" + ws
+ out.join(',' + (pretty ? ws : ' '))
+ (pretty ? ws.slice(0, -4) : ws) +
"}";
}
};
// A better `typeof`
function typeOf(value) {
var s = typeof(value),
types = [Object, Array, String, RegExp, Number, Function, Boolean, Date];
if (s === 'object' || s === 'function') {
if (value) {
types.forEach(function (t) {
if (value instanceof t) { s = t.name.toLowerCase() }
});
} else { s = 'null' }
}
return s;
}
function merge(/* variable args */) {
var objs = Array.prototype.slice.call(arguments);
var target = {};
objs.forEach(function (o) {
Object.keys(o).forEach(function (k) {
if (k === 'styles') {
if (! o.styles) {
target.styles = false;
} else {
target.styles = {}
for (var s in o.styles) {
target.styles[s] = o.styles[s];
}
}
} else {
target[k] = o[k];
}
});
});
return target;
}