From 5b8ac58ed8a54f46d28b5cca61fec6d42e1cf6ab Mon Sep 17 00:00:00 2001 From: Ruben Bridgewater Date: Sun, 27 Jan 2019 16:07:00 +0100 Subject: [PATCH] path: refactor code for clarity MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This moves a condition inside of a for loop which can only be triggered at the very end of the for loop outside of the loop. That way the for loop itself is much simpler and easier to understand and the code itself is less indented which should increase the readability. It also refactors some `var` to `let` and `const`. PR-URL: https://github.com/nodejs/node/pull/25278 Reviewed-By: Michaël Zasso --- lib/path.js | 128 ++++++++++++++++++++++++++-------------------------- 1 file changed, 63 insertions(+), 65 deletions(-) diff --git a/lib/path.js b/lib/path.js index 64cd5eee92c8e3..6ac65cfe4a7a3f 100644 --- a/lib/path.js +++ b/lib/path.js @@ -478,38 +478,12 @@ const win32 = { const toLen = toEnd - toStart; // Compare paths to find the longest common path from root - var length = (fromLen < toLen ? fromLen : toLen); - var lastCommonSep = -1; - var i = 0; - for (; i <= length; ++i) { - if (i === length) { - if (toLen > length) { - if (to.charCodeAt(toStart + i) === CHAR_BACKWARD_SLASH) { - // We get here if `from` is the exact base path for `to`. - // For example: from='C:\\foo\\bar'; to='C:\\foo\\bar\\baz' - return toOrig.slice(toStart + i + 1); - } else if (i === 2) { - // We get here if `from` is the device root. - // For example: from='C:\\'; to='C:\\foo' - return toOrig.slice(toStart + i); - } - } - if (fromLen > length) { - if (from.charCodeAt(fromStart + i) === CHAR_BACKWARD_SLASH) { - // We get here if `to` is the exact base path for `from`. - // For example: from='C:\\foo\\bar'; to='C:\\foo' - lastCommonSep = i; - } else if (i === 2) { - // We get here if `to` is the device root. - // For example: from='C:\\foo\\bar'; to='C:\\' - lastCommonSep = 3; - } - } - break; - } - var fromCode = from.charCodeAt(fromStart + i); - var toCode = to.charCodeAt(toStart + i); - if (fromCode !== toCode) + const length = fromLen < toLen ? fromLen : toLen; + let lastCommonSep = -1; + let i = 0; + for (; i < length; i++) { + const fromCode = from.charCodeAt(fromStart + i); + if (fromCode !== to.charCodeAt(toStart + i)) break; else if (fromCode === CHAR_BACKWARD_SLASH) lastCommonSep = i; @@ -517,8 +491,33 @@ const win32 = { // We found a mismatch before the first common path separator was seen, so // return the original `to`. - if (i !== length && lastCommonSep === -1) { - return toOrig; + if (i !== length) { + if (lastCommonSep === -1) + return toOrig; + } else { + if (toLen > length) { + if (to.charCodeAt(toStart + i) === CHAR_BACKWARD_SLASH) { + // We get here if `from` is the exact base path for `to`. + // For example: from='C:\\foo\\bar'; to='C:\\foo\\bar\\baz' + return toOrig.slice(toStart + i + 1); + } + if (i === 2) { + // We get here if `from` is the device root. + // For example: from='C:\\'; to='C:\\foo' + return toOrig.slice(toStart + i); + } + } + if (fromLen > length) { + if (from.charCodeAt(fromStart + i) === CHAR_BACKWARD_SLASH) { + // We get here if `to` is the exact base path for `from`. + // For example: from='C:\\foo\\bar'; to='C:\\foo' + lastCommonSep = i; + } else if (i === 2) { + // We get here if `to` is the device root. + // For example: from='C:\\foo\\bar'; to='C:\\' + lastCommonSep = 3; + } + } } let out = ''; @@ -1079,41 +1078,40 @@ const posix = { const toLen = (toEnd - toStart); // Compare paths to find the longest common path from root - var length = (fromLen < toLen ? fromLen : toLen); - var lastCommonSep = -1; - var i = 0; - for (; i <= length; ++i) { - if (i === length) { - if (toLen > length) { - if (to.charCodeAt(toStart + i) === CHAR_FORWARD_SLASH) { - // We get here if `from` is the exact base path for `to`. - // For example: from='/foo/bar'; to='/foo/bar/baz' - return to.slice(toStart + i + 1); - } else if (i === 0) { - // We get here if `from` is the root - // For example: from='/'; to='/foo' - return to.slice(toStart + i); - } - } else if (fromLen > length) { - if (from.charCodeAt(fromStart + i) === CHAR_FORWARD_SLASH) { - // We get here if `to` is the exact base path for `from`. - // For example: from='/foo/bar/baz'; to='/foo/bar' - lastCommonSep = i; - } else if (i === 0) { - // We get here if `to` is the root. - // For example: from='/foo'; to='/' - lastCommonSep = 0; - } - } - break; - } - var fromCode = from.charCodeAt(fromStart + i); - var toCode = to.charCodeAt(toStart + i); - if (fromCode !== toCode) + const length = (fromLen < toLen ? fromLen : toLen); + let lastCommonSep = -1; + let i = 0; + for (; i < length; i++) { + const fromCode = from.charCodeAt(fromStart + i); + if (fromCode !== to.charCodeAt(toStart + i)) break; else if (fromCode === CHAR_FORWARD_SLASH) lastCommonSep = i; } + if (i === length) { + if (toLen > length) { + if (to.charCodeAt(toStart + i) === CHAR_FORWARD_SLASH) { + // We get here if `from` is the exact base path for `to`. + // For example: from='/foo/bar'; to='/foo/bar/baz' + return to.slice(toStart + i + 1); + } + if (i === 0) { + // We get here if `from` is the root + // For example: from='/'; to='/foo' + return to.slice(toStart + i); + } + } else if (fromLen > length) { + if (from.charCodeAt(fromStart + i) === CHAR_FORWARD_SLASH) { + // We get here if `to` is the exact base path for `from`. + // For example: from='/foo/bar/baz'; to='/foo/bar' + lastCommonSep = i; + } else if (i === 0) { + // We get here if `to` is the root. + // For example: from='/foo'; to='/' + lastCommonSep = 0; + } + } + } var out = ''; // Generate the relative path based on the path difference between `to`