More path utils

totten · Dec 3, 2019 · 84f690c · 84f690c
1 parent 3025964
commit 84f690c
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diff --git a/src/PathUtil.php b/src/PathUtil.php
@@ -3,6 +3,8 @@
 
 class PathUtil {
 
+  public static $SEP = DIRECTORY_SEPARATOR;
+
   public static function getPwd() {
     if (getenv('PWD')) {
       // Symlink sensitivity training
@@ -29,4 +31,75 @@ public static function findCommand($name) {
     return NULL;
   }
 
+  /**
+   * Convert relative paths to absolute
+   *
+   * @param $expr
+   * @param string|NULL $base
+   * @return string
+   */
+  public static function makeAbsolute($expr, $base = NULL) {
+    if (self::isAbsolute($expr)) {
+      return $expr;
+    }
+
+    if ($base === NULL) {
+      $base = self::getPwd();
+    }
+
+    $base = rtrim($base, '/' . self::$SEP);
+    return $base . self::$SEP . $expr;
+  }
+
+  public static function isAbsolute($expr) {
+    $slashes = '/' . self::$SEP;
+    if (strpos($slashes, $expr[0]) !== FALSE) {
+      return TRUE;
+    }
+    if (self::$SEP === '\\' && preg_match(';^[a-zA-Z]:[\\/];', $expr)) {
+      return TRUE;
+    }
+    return FALSE;
+  }
+
+  /**
+   * Evaluate as many expressions like "/./" or "/../" as we can.
+   *
+   * If the path is relative, then the leading "../" may not be evaluated.
+   *
+   * @param string $path
+   * @return string
+   */
+  public static function evaluateDots($path) {
+    $q = preg_quote(self::$SEP, ';');
+
+    $path = self::cleanSlashes($path);
+    $hasTail = substr($path, -1) === self::$SEP ? self::$SEP : '';
+    if (!$hasTail) {
+      $path .= self::$SEP;
+    }
+
+    $path = preg_replace(";^(\.{$q})+(.);", '$2', $path);
+    while (preg_match(";{$q}\.\.?{$q};", $path)) {
+      $path = preg_replace(";{$q}\.{$q};", self::$SEP, $path);
+      $path = preg_replace(";{$q}[^{$q}]+{$q}\.\.{$q};", self::$SEP, $path);
+    }
+    return $hasTail ? $path : rtrim($path, self::$SEP);
+  }
+
+  /**
+   * @param $path
+   * @param $preferredSeparator
+   * @return array
+   */
+  public static function cleanSlashes($path) {
+    if (self::$SEP !== '/') {
+      $path = str_replace('/', self::$SEP, $path);
+    }
+
+    $q = preg_quote(self::$SEP, ';');
+    $path = preg_replace(";{$q}+;", self::$SEP, $path);
+    return $path;
+  }
+
 }
diff --git a/tests/PathUtilTest.php b/tests/PathUtilTest.php
@@ -0,0 +1,43 @@
+<?php
+namespace Pogo;
+
+use PHPUnit\Framework\TestCase;
+
+class PathUtilTest extends TestCase {
+
+  public function getDotExamples() {
+    $exs = [
+      ["/", "/unix/abs", "/unix/abs"],
+      ["/", "unix/rel", "unix/rel"],
+      ["/", "c:/win/abs", "c:/win/abs"],
+      ["/", "win/rel", "win/rel"],
+      ["/", "/c:/win/abs", "/c:/win/abs"],
+      ["/", "/unix/foo/bar/..", "/unix/foo"],
+      ["/", "/unix/foo/bar/../", "/unix/foo/"],
+      ["/", "/unix/foo/bar/.", "/unix/foo/bar"],
+      ["/", "/unix/foo/bar/./", "/unix/foo/bar/"],
+      ["/", "/unix/foo/./bar", "/unix/foo/bar"],
+      ["/", ".", "."],
+      ["/", "../", "../"],
+      ["/", "..", ".."],
+      ["/", "./foo", "foo"],
+      ["/", "../foo/bar", "../foo/bar"],
+      ["/", ".foo", ".foo"],
+    ];
+    return $exs;
+  }
+
+  /**
+   * @param string $sep
+   * @param string $inputPath
+   * @param string $expectPath
+   * @dataProvider getDotExamples
+   */
+  public function testEvaluateDots($sep, $inputPath, $expectPath) {
+    $origSep = PathUtil::$SEP;
+    PathUtil::$SEP = $sep;
+    $this->assertEquals($expectPath, PathUtil::evaluateDots($inputPath));
+    PathUtil::$SEP = $origSep;
+  }
+
+}