util: Divide inspect() into some subroutines

lib/util.js

@@ -95,12 +95,19 @@ var error = exports.error = function(x) {
  *    output. Default is false (no coloring).
  */
 function inspect(obj, showHidden, depth, colors) {
-  var seen = [];
+  var ctx = {
+    showHidden: showHidden,
+    seen: [],
+    stylize: colors ? stylizeWithColor : stylizeNoColor,
+  };
+  return formatValue(ctx, obj, (typeof depth === 'undefined' ? 2 : depth));
+}
+exports.inspect = inspect;
 
-  var stylize = function(str, styleType) {
+
-    // http://en.wikipedia.org/wiki/ANSI_escape_code#graphics
+// http://en.wikipedia.org/wiki/ANSI_escape_code#graphics
-    var styles =
+var colors = {
-        { 'bold' : [1, 22],
+   'bold' : [1, 22],
    'italic' : [3, 23],
    'underline' : [4, 24],
    'inverse' : [7, 27],
@@ -112,10 +119,11 @@ function inspect(obj, showHidden, depth, colors) {
    'green' : [32, 39],
    'magenta' : [35, 39],
    'red' : [31, 39],
-          'yellow' : [33, 39] };
+   'yellow' : [33, 39]
+};
 
-    var style =
+var styles = {
-        { 'special': 'cyan',
+   'special': 'cyan',
    'number': 'blue',
    'boolean': 'yellow',
    'undefined': 'grey',
@@ -123,20 +131,28 @@ function inspect(obj, showHidden, depth, colors) {
    'string': 'green',
    'date': 'magenta',
    // "name": intentionally not styling
-          'regexp': 'red' }[styleType];
+   'regexp': 'red'
+};
+
+
+function stylizeWithColor(str, styleType) {
+  var style = styles[styleType];
 
   if (style) {
-      return '\033[' + styles[style][0] + 'm' + str +
+    return '\033[' + colors[style][0] + 'm' + str +
-             '\033[' + styles[style][1] + 'm';
+           '\033[' + colors[style][1] + 'm';
   } else {
     return str;
   }
-  };
+}
-  if (! colors) {
+
-    stylize = function(str, styleType) { return str; };
-  }
 
-  function format(value, recurseTimes) {
+function stylizeNoColor(str, styleType) {
+  return str;
+}
+
+
+function formatValue(ctx, value, recurseTimes) {
   // Provide a hook for user-specified inspect functions.
   // Check that value is an object with an inspect function on it
   if (value && typeof value.inspect === 'function' &&
@@ -148,63 +164,41 @@ function inspect(obj, showHidden, depth, colors) {
   }
 
   // Primitive types cannot have properties
-    switch (typeof value) {
+  var primitive = formatPrimitive(ctx, value);
-      case 'undefined':
+  if (primitive) {
-        return stylize('undefined', 'undefined');
+    return primitive;
-
-      case 'string':
-        var simple = '\'' + JSON.stringify(value).replace(/^"|"$/g, '')
-                                                 .replace(/'/g, "\\'")
-                                                 .replace(/\\"/g, '"') + '\'';
-        return stylize(simple, 'string');
-
-      case 'number':
-        return stylize('' + value, 'number');
-
-      case 'boolean':
-        return stylize('' + value, 'boolean');
-    }
-    // For some reason typeof null is "object", so special case here.
-    if (value === null) {
-      return stylize('null', 'null');
   }
 
   // Look up the keys of the object.
-    var visible_keys = Object.keys(value);
+  var visibleKeys = Object.keys(value);
-    var keys = showHidden ? Object.getOwnPropertyNames(value) : visible_keys;
+  var keys = ctx.showHidden ? Object.getOwnPropertyNames(value) : visibleKeys;
 
-    // Functions without properties can be shortcutted.
+  // Some type of object without properties can be shortcutted.
-    if (typeof value === 'function' && keys.length === 0) {
+  if (keys.length === 0) {
+    if (typeof value === 'function') {
       var name = value.name ? ': ' + value.name : '';
-      return stylize('[Function' + name + ']', 'special');
+      return ctx.stylize('[Function' + name + ']', 'special');
     }
-
+    if (isRegExp(value)) {
-    // RegExp without properties can be shortcutted
+      return ctx.stylize('' + value, 'regexp');
-    if (isRegExp(value) && keys.length === 0) {
-      return stylize('' + value, 'regexp');
     }
-
+    if (isDate(value)) {
-    // Dates without properties can be shortcutted
+      return ctx.stylize(value.toUTCString(), 'date');
-    if (isDate(value) && keys.length === 0) {
-      return stylize(value.toUTCString(), 'date');
     }
+  }
+
+  var base = '', array = false, braces = ['{', '}'];
 
-    var base, type, braces;
+  // Make Array say that they are Array
-    // Determine the object type
   if (isArray(value)) {
-      type = 'Array';
+    array = true;
     braces = ['[', ']'];
-    } else {
-      type = 'Object';
-      braces = ['{', '}'];
   }
 
   // Make functions say that they are functions
   if (typeof value === 'function') {
     var n = value.name ? ': ' + value.name : '';
     base = ' [Function' + n + ']';
-    } else {
-      base = '';
   }
 
   // Make RegExps say that they are RegExps
@@ -223,41 +217,75 @@ function inspect(obj, showHidden, depth, colors) {
 
   if (recurseTimes < 0) {
     if (isRegExp(value)) {
-        return stylize('' + value, 'regexp');
+      return ctx.stylize('' + value, 'regexp');
     } else {
-        return stylize('[Object]', 'special');
+      return ctx.stylize('[Object]', 'special');
     }
   }
 
-    seen.push(value);
+  ctx.seen.push(value);
 
   var output = keys.map(function(key) {
+    return formatProperty(ctx, value, recurseTimes, visibleKeys, key, array);
+  });
+
+  ctx.seen.pop();
+
+  return reduceToSingleString(output, base, braces);
+}
+
+
+function formatPrimitive(ctx, value) {
+  switch (typeof value) {
+    case 'undefined':
+      return ctx.stylize('undefined', 'undefined');
+
+    case 'string':
+      var simple = '\'' + JSON.stringify(value).replace(/^"|"$/g, '')
+                                               .replace(/'/g, "\\'")
+                                               .replace(/\\"/g, '"') + '\'';
+      return ctx.stylize(simple, 'string');
+
+    case 'number':
+      return ctx.stylize('' + value, 'number');
+
+    case 'boolean':
+      return ctx.stylize('' + value, 'boolean');
+  }
+  // For some reason typeof null is "object", so special case here.
+  if (value === null) {
+    return ctx.stylize('null', 'null');
+  }
+}
+
+
+function formatProperty(ctx, value, recurseTimes, visibleKeys, key, array) {
   var name, str;
   if (value.__lookupGetter__) {
     if (value.__lookupGetter__(key)) {
       if (value.__lookupSetter__(key)) {
-            str = stylize('[Getter/Setter]', 'special');
+        str = ctx.stylize('[Getter/Setter]', 'special');
       } else {
-            str = stylize('[Getter]', 'special');
+        str = ctx.stylize('[Getter]', 'special');
       }
     } else {
       if (value.__lookupSetter__(key)) {
-            str = stylize('[Setter]', 'special');
+        str = ctx.stylize('[Setter]', 'special');
       }
     }
   }
-      if (visible_keys.indexOf(key) < 0) {
+  if (visibleKeys.indexOf(key) < 0) {
     name = '[' + key + ']';
   }
   if (!str) {
-        if (seen.indexOf(value[key]) < 0) {
+    if (ctx.seen.indexOf(value[key]) < 0) {
       if (recurseTimes === null) {
-            str = format(value[key]);
+        str = formatValue(ctx, value[key], null);
       } else {
-            str = format(value[key], recurseTimes - 1);
+        str = formatValue(ctx, value[key], recurseTimes - 1);
       }
       if (str.indexOf('\n') > -1) {
-            if (isArray(value)) {
+        if (array) {
           str = str.split('\n').map(function(line) {
             return '  ' + line;
           }).join('\n').substr(2);
@@ -268,30 +296,30 @@ function inspect(obj, showHidden, depth, colors) {
         }
       }
     } else {
-          str = stylize('[Circular]', 'special');
+      str = ctx.stylize('[Circular]', 'special');
     }
   }
   if (typeof name === 'undefined') {
-        if (type === 'Array' && key.match(/^\d+$/)) {
+    if (array && key.match(/^\d+$/)) {
       return str;
     }
     name = JSON.stringify('' + key);
     if (name.match(/^"([a-zA-Z_][a-zA-Z_0-9]*)"$/)) {
       name = name.substr(1, name.length - 2);
-          name = stylize(name, 'name');
+      name = ctx.stylize(name, 'name');
     } else {
       name = name.replace(/'/g, "\\'")
                  .replace(/\\"/g, '"')
                  .replace(/(^"|"$)/g, "'");
-          name = stylize(name, 'string');
+      name = ctx.stylize(name, 'string');
     }
   }
 
   return name + ': ' + str;
-    });
+}
 
-    seen.pop();
 
+function reduceToSingleString(output, base, braces) {
   var numLinesEst = 0;
   var length = output.reduce(function(prev, cur) {
     numLinesEst++;
@@ -300,22 +328,16 @@ function inspect(obj, showHidden, depth, colors) {
   }, 0);
 
   if (length > (require('readline').columns || 50)) {
-      output = braces[0] +
+    return braces[0] +
            (base === '' ? '' : base + '\n ') +
            ' ' +
            output.join(',\n  ') +
            ' ' +
            braces[1];
-
-    } else {
-      output = braces[0] + base + ' ' + output.join(', ') + ' ' + braces[1];
   }
 
-    return output;
+  return braces[0] + base + ' ' + output.join(', ') + ' ' + braces[1];
-  }
-  return format(obj, (typeof depth === 'undefined' ? 2 : depth));
 }
-exports.inspect = inspect;
 
 
 function isArray(ar) {