url: replace "magic" numbers by constants

PR-URL: https://github.com/nodejs/node/pull/19035
Reviewed-By: Myles Borins <myles.borins@gmail.com>
Reviewed-By: Daijiro Wachi <daijiro.wachi@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Khaidi Chu <i@2333.moe>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>

2 files changed, 109 insertions, 49 deletions

diff --git a/lib/internal/constants.js b/lib/internal/constants.js
index 93bf926a84..6fc16e57d9 100644
--- a/lib/internal/constants.js
+++ b/lib/internal/constants.js
@@ -11,13 +11,34 @@ module.exports = {
   CHAR_DOT: 46, /* . */
   CHAR_FORWARD_SLASH: 47, /* / */
   CHAR_BACKWARD_SLASH: 92, /* \ */
+  CHAR_VERTICAL_LINE: 124, /* | */
   CHAR_COLON: 58, /* : */
   CHAR_QUESTION_MARK: 63, /* ? */
   CHAR_UNDERSCORE: 95, /* _ */
   CHAR_LINE_FEED: 10, /* \n */
   CHAR_CARRIAGE_RETURN: 13, /* \r */
+  CHAR_TAB: 9, /* \t */
+  CHAR_FORM_FEED: 12, /* \f */
   CHAR_EXCLAMATION_MARK: 33, /* ! */
   CHAR_HASH: 35, /* # */
+  CHAR_SPACE: 32, /*   */
+  CHAR_NO_BREAK_SPACE: 160, /* \u00A0 */
+  CHAR_ZERO_WIDTH_NOBREAK_SPACE: 65279, /* \uFEFF */
+  CHAR_LEFT_SQUARE_BRACKET: 91, /* [ */
+  CHAR_RIGHT_SQUARE_BRACKET: 93, /* ] */
+  CHAR_LEFT_ANGLE_BRACKET: 60, /* < */
+  CHAR_RIGHT_ANGLE_BRACKET: 62, /* > */
+  CHAR_LEFT_CURLY_BRACKET: 123, /* { */
+  CHAR_RIGHT_CURLY_BRACKET: 125, /* } */
+  CHAR_HYPHEN_MINUS: 45, /* - */
+  CHAR_PLUS: 43, /* + */
+  CHAR_DOUBLE_QUOTE: 34, /* " */
+  CHAR_SINGLE_QUOTE: 39, /* ' */
+  CHAR_PERCENT: 37, /* % */
+  CHAR_SEMICOLON: 59, /* ; */
+  CHAR_CIRCUMFLEX_ACCENT: 94, /* ^ */
+  CHAR_GRAVE_ACCENT: 96, /* ` */
+  CHAR_AT: 64, /* @ */
 
   // Digits
   CHAR_0: 48, /* 0 */
diff --git a/lib/url.js b/lib/url.js
index bb6637809a..61662b4a97 100644
--- a/lib/url.js
+++ b/lib/url.js
@@ -94,6 +94,43 @@ const slashedProtocol = {
   'file:': true
 };
 const querystring = require('querystring');
+const {
+  CHAR_SPACE,
+  CHAR_TAB,
+  CHAR_CARRIAGE_RETURN,
+  CHAR_LINE_FEED,
+  CHAR_FORM_FEED,
+  CHAR_NO_BREAK_SPACE,
+  CHAR_ZERO_WIDTH_NOBREAK_SPACE,
+  CHAR_HASH,
+  CHAR_FORWARD_SLASH,
+  CHAR_LEFT_SQUARE_BRACKET,
+  CHAR_RIGHT_SQUARE_BRACKET,
+  CHAR_LEFT_ANGLE_BRACKET,
+  CHAR_RIGHT_ANGLE_BRACKET,
+  CHAR_LEFT_CURLY_BRACKET,
+  CHAR_RIGHT_CURLY_BRACKET,
+  CHAR_QUESTION_MARK,
+  CHAR_LOWERCASE_A,
+  CHAR_LOWERCASE_Z,
+  CHAR_UPPERCASE_A,
+  CHAR_UPPERCASE_Z,
+  CHAR_DOT,
+  CHAR_0,
+  CHAR_9,
+  CHAR_HYPHEN_MINUS,
+  CHAR_PLUS,
+  CHAR_UNDERSCORE,
+  CHAR_DOUBLE_QUOTE,
+  CHAR_SINGLE_QUOTE,
+  CHAR_PERCENT,
+  CHAR_SEMICOLON,
+  CHAR_BACKWARD_SLASH,
+  CHAR_CIRCUMFLEX_ACCENT,
+  CHAR_GRAVE_ACCENT,
+  CHAR_VERTICAL_LINE,
+  CHAR_AT,
+} = require('internal/constants');
 
 function urlParse(url, parseQueryString, slashesDenoteHost) {
   if (url instanceof Url) return url;
@@ -121,13 +158,13 @@ Url.prototype.parse = function parse(url, parseQueryString, slashesDenoteHost) {
     const code = url.charCodeAt(i);
 
     // Find first and last non-whitespace characters for trimming
-    const isWs = code === 32/* */ ||
-                 code === 9/*\t*/ ||
-                 code === 13/*\r*/ ||
-                 code === 10/*\n*/ ||
-                 code === 12/*\f*/ ||
-                 code === 160/*\u00A0*/ ||
-                 code === 65279/*\uFEFF*/;
+    const isWs = code === CHAR_SPACE ||
+                 code === CHAR_TAB ||
+                 code === CHAR_CARRIAGE_RETURN ||
+                 code === CHAR_LINE_FEED ||
+                 code === CHAR_FORM_FEED ||
+                 code === CHAR_NO_BREAK_SPACE ||
+                 code === CHAR_ZERO_WIDTH_NOBREAK_SPACE;
     if (start === -1) {
       if (isWs)
         continue;
@@ -145,20 +182,20 @@ Url.prototype.parse = function parse(url, parseQueryString, slashesDenoteHost) {
     // Only convert backslashes while we haven't seen a split character
     if (!split) {
       switch (code) {
-        case 35: // '#'
+        case CHAR_HASH:
           hasHash = true;
         // Fall through
-        case 63: // '?'
+        case CHAR_QUESTION_MARK:
           split = true;
           break;
-        case 92: // '\\'
+        case CHAR_BACKWARD_SLASH:
           if (i - lastPos > 0)
             rest += url.slice(lastPos, i);
           rest += '/';
           lastPos = i + 1;
           break;
       }
-    } else if (!hasHash && code === 35/*#*/) {
+    } else if (!hasHash && code === CHAR_HASH) {
       hasHash = true;
     }
   }
@@ -220,8 +257,8 @@ Url.prototype.parse = function parse(url, parseQueryString, slashesDenoteHost) {
   // resolution will treat //foo/bar as host=foo,path=bar because that's
   // how the browser resolves relative URLs.
   if (slashesDenoteHost || proto || hostPattern.test(rest)) {
-    var slashes = rest.charCodeAt(0) === 47/*/*/ &&
-                  rest.charCodeAt(1) === 47/*/*/;
+    var slashes = rest.charCodeAt(0) === CHAR_FORWARD_SLASH &&
+                  rest.charCodeAt(1) === CHAR_FORWARD_SLASH;
     if (slashes && !(proto && hostlessProtocol[proto])) {
       rest = rest.slice(2);
       this.slashes = true;
@@ -251,35 +288,35 @@ Url.prototype.parse = function parse(url, parseQueryString, slashesDenoteHost) {
     var nonHost = -1;
     for (i = 0; i < rest.length; ++i) {
       switch (rest.charCodeAt(i)) {
-        case 9:   // '\t'
-        case 10:  // '\n'
-        case 13:  // '\r'
-        case 32:  // ' '
-        case 34:  // '"'
-        case 37:  // '%'
-        case 39:  // '\''
-        case 59:  // ';'
-        case 60:  // '<'
-        case 62:  // '>'
-        case 92:  // '\\'
-        case 94:  // '^'
-        case 96:  // '`'
-        case 123: // '{'
-        case 124: // '|'
-        case 125: // '}'
+        case CHAR_TAB:
+        case CHAR_LINE_FEED:
+        case CHAR_CARRIAGE_RETURN:
+        case CHAR_SPACE:
+        case CHAR_DOUBLE_QUOTE:
+        case CHAR_PERCENT:
+        case CHAR_SINGLE_QUOTE:
+        case CHAR_SEMICOLON:
+        case CHAR_LEFT_ANGLE_BRACKET:
+        case CHAR_RIGHT_ANGLE_BRACKET:
+        case CHAR_BACKWARD_SLASH:
+        case CHAR_CIRCUMFLEX_ACCENT:
+        case CHAR_GRAVE_ACCENT:
+        case CHAR_LEFT_CURLY_BRACKET:
+        case CHAR_VERTICAL_LINE:
+        case CHAR_RIGHT_CURLY_BRACKET:
           // Characters that are never ever allowed in a hostname from RFC 2396
           if (nonHost === -1)
             nonHost = i;
           break;
-        case 35: // '#'
-        case 47: // '/'
-        case 63: // '?'
+        case CHAR_HASH:
+        case CHAR_FORWARD_SLASH:
+        case CHAR_QUESTION_MARK:
           // Find the first instance of any host-ending characters
           if (nonHost === -1)
             nonHost = i;
           hostEnd = i;
           break;
-        case 64: // '@'
+        case CHAR_AT:
           // At this point, either we have an explicit point where the
           // auth portion cannot go past, or the last @ char is the decider.
           atSign = i;
@@ -314,8 +351,8 @@ Url.prototype.parse = function parse(url, parseQueryString, slashesDenoteHost) {
 
     // if hostname begins with [ and ends with ]
     // assume that it's an IPv6 address.
-    var ipv6Hostname = hostname.charCodeAt(0) === 91/*[*/ &&
-                       hostname.charCodeAt(hostname.length - 1) === 93/*]*/;
+    var ipv6Hostname = hostname.charCodeAt(0) === CHAR_LEFT_SQUARE_BRACKET &&
+      hostname.charCodeAt(hostname.length - 1) === CHAR_RIGHT_SQUARE_BRACKET;
 
     // validate a little.
     if (!ipv6Hostname) {
@@ -369,11 +406,11 @@ Url.prototype.parse = function parse(url, parseQueryString, slashesDenoteHost) {
   var hashIdx = -1;
   for (i = 0; i < rest.length; ++i) {
     const code = rest.charCodeAt(i);
-    if (code === 35/*#*/) {
+    if (code === CHAR_HASH) {
       this.hash = rest.slice(i);
       hashIdx = i;
       break;
-    } else if (code === 63/*?*/ && questionIdx === -1) {
+    } else if (code === CHAR_QUESTION_MARK && questionIdx === -1) {
       questionIdx = i;
     }
   }
@@ -424,13 +461,13 @@ Url.prototype.parse = function parse(url, parseQueryString, slashesDenoteHost) {
 function validateHostname(self, rest, hostname) {
   for (var i = 0; i < hostname.length; ++i) {
     const code = hostname.charCodeAt(i);
-    const isValid = (code >= 97/*a*/ && code <= 122/*z*/) ||
-                    code === 46/*.*/ ||
-                    (code >= 65/*A*/ && code <= 90/*Z*/) ||
-                    (code >= 48/*0*/ && code <= 57/*9*/) ||
-                    code === 45/*-*/ ||
-                    code === 43/*+*/ ||
-                    code === 95/*_*/ ||
+    const isValid = (code >= CHAR_LOWERCASE_A && code <= CHAR_LOWERCASE_Z) ||
+                    code === CHAR_DOT ||
+                    (code >= CHAR_UPPERCASE_A && code <= CHAR_UPPERCASE_Z) ||
+                    (code >= CHAR_0 && code <= CHAR_9) ||
+                    code === CHAR_HYPHEN_MINUS ||
+                    code === CHAR_PLUS ||
+                    code === CHAR_UNDERSCORE ||
                     code > 127;
 
     // Invalid host character
@@ -544,13 +581,13 @@ Url.prototype.format = function format() {
   var lastPos = 0;
   for (var i = 0; i < pathname.length; ++i) {
     switch (pathname.charCodeAt(i)) {
-      case 35: // '#'
+      case CHAR_HASH:
         if (i - lastPos > 0)
           newPathname += pathname.slice(lastPos, i);
         newPathname += '%23';
         lastPos = i + 1;
         break;
-      case 63: // '?'
+      case CHAR_QUESTION_MARK:
         if (i - lastPos > 0)
           newPathname += pathname.slice(lastPos, i);
         newPathname += '%3F';
@@ -569,7 +606,7 @@ Url.prototype.format = function format() {
   // unless they had them to begin with.
   if (this.slashes || slashedProtocol[protocol]) {
     if (this.slashes || host) {
-      if (pathname && pathname.charCodeAt(0) !== 47/*/*/)
+      if (pathname && pathname.charCodeAt(0) !== CHAR_FORWARD_SLASH)
         pathname = '/' + pathname;
       host = '//' + host;
     } else if (protocol.length >= 4 &&
@@ -583,8 +620,10 @@ Url.prototype.format = function format() {
 
   search = search.replace(/#/g, '%23');
 
-  if (hash && hash.charCodeAt(0) !== 35/*#*/) hash = '#' + hash;
-  if (search && search.charCodeAt(0) !== 63/*?*/) search = '?' + search;
+  if (hash && hash.charCodeAt(0) !== CHAR_HASH)
+    hash = '#' + hash;
+  if (search && search.charCodeAt(0) !== CHAR_QUESTION_MARK)
+    search = '?' + search;
 
   return protocol + host + pathname + search + hash;
 };