Ensure user-provided SupportVectorMachine paths are valid (#126)

src/Phpml/Exception/InvalidArgumentException.php

@@ -39,7 +39,7 @@ public static function arrayCantBeEmpty()
      */
     public static function arraySizeToSmall($minimumSize = 2)
     {
-        return new self(sprintf('The array must have at least %s elements', $minimumSize));
+        return new self(sprintf('The array must have at least %d elements', $minimumSize));
     }
 
     /**
@@ -73,7 +73,7 @@ public static function invalidClustersNumber()
      */
     public static function invalidTarget($target)
     {
-        return new self('Target with value '.$target.' is not part of the accepted classes');
+        return new self(sprintf('Target with value "%s" is not part of the accepted classes', $target));
     }
 
     /**
@@ -83,7 +83,7 @@ public static function invalidTarget($target)
      */
     public static function invalidStopWordsLanguage(string $language)
     {
-        return new self(sprintf('Can\'t find %s language for StopWords', $language));
+        return new self(sprintf('Can\'t find "%s" language for StopWords', $language));
     }
 
     /**
@@ -110,8 +110,51 @@ public static function invalidClassesNumber()
         return new self('Provide at least 2 different classes');
     }
 
+    /**
+     * @return InvalidArgumentException
+     */
     public static function inconsistentClasses()
     {
         return new self('The provided classes don\'t match the classes provided in the constructor');
     }
+
+    /**
+     * @param string $file
+     *
+     * @return InvalidArgumentException
+     */
+    public static function fileNotFound(string $file)
+    {
+        return new self(sprintf('File "%s" not found', $file));
+    }
+
+    /**
+     * @param string $file
+     *
+     * @return InvalidArgumentException
+     */
+    public static function fileNotExecutable(string $file)
+    {
+        return new self(sprintf('File "%s" is not executable', $file));
+    }
+
+    /**
+     * @param string $path
+     *
+     * @return InvalidArgumentException
+     */
+    public static function pathNotFound(string $path)
+    {
+        return new self(sprintf('The specified path "%s" does not exist', $path));
+    }
+
+    /**
+     * @param string $path
+     *
+     * @return InvalidArgumentException
+     */
+    public static function pathNotWritable(string $path)
+    {
+        return new self(sprintf('The specified path "%s" is not writable', $path));
+    }
 }

src/Phpml/SupportVectorMachine/SupportVectorMachine.php

@@ -4,6 +4,7 @@
 
 namespace Phpml\SupportVectorMachine;
 
+use Phpml\Exception\InvalidArgumentException;
 use Phpml\Helper\Trainable;
 
 class SupportVectorMachine
@@ -140,25 +141,29 @@ public function __construct(
     /**
      * @param string $binPath
      *
-     * @return $this
+     * @throws InvalidArgumentException
      */
     public function setBinPath(string $binPath)
     {
-        $this->binPath = $binPath;
+        $this->ensureDirectorySeparator($binPath);
+        $this->verifyBinPath($binPath);
 
-        return $this;
+        $this->binPath = $binPath;
     }
 
     /**
      * @param string $varPath
      *
-     * @return $this
+     * @throws InvalidArgumentException
      */
     public function setVarPath(string $varPath)
     {
-        $this->varPath = $varPath;
+        if (!is_writable($varPath)) {
+            throw InvalidArgumentException::pathNotWritable($varPath);
+        }
 
-        return $this;
+        $this->ensureDirectorySeparator($varPath);
+        $this->varPath = $varPath;
     }
 
     /**
@@ -270,4 +275,38 @@ private function buildTrainCommand(string $trainingSetFileName, string $modelFil
             escapeshellarg($modelFileName)
         );
     }
+
+    /**
+     * @param string $path
+     */
+    private function ensureDirectorySeparator(string &$path)
+    {
+        if (substr($path, -1) !== DIRECTORY_SEPARATOR) {
+            $path .= DIRECTORY_SEPARATOR;
+        }
+    }
+
+    /**
+     * @param string $path
+     *
+     * @throws InvalidArgumentException
+     */
+    private function verifyBinPath(string $path)
+    {
+        if (!is_dir($path)) {
+            throw InvalidArgumentException::pathNotFound($path);
+        }
+
+        $osExtension = $this->getOSExtension();
+        foreach (['svm-predict', 'svm-scale', 'svm-train'] as $filename) {
+            $filePath = $path.$filename.$osExtension;
+            if (!file_exists($filePath)) {
+                throw InvalidArgumentException::fileNotFound($filePath);
+            }
+
+            if (!is_executable($filePath)) {
+                throw InvalidArgumentException::fileNotExecutable($filePath);
+            }
+        }
+    }
 }

tests/Phpml/SupportVectorMachine/SupportVectorMachineTest.php

@@ -80,4 +80,34 @@ public function testPredictSampleFromMultipleClassWithRbfKernel()
         $this->assertEquals('b', $predictions[1]);
         $this->assertEquals('c', $predictions[2]);
     }
+
+    /**
+     * @expectedException \Phpml\Exception\InvalidArgumentException
+     * @expectedExceptionMessage is not writable
+     */
+    public function testThrowExceptionWhenVarPathIsNotWritable()
+    {
+        $svm = new SupportVectorMachine(Type::C_SVC, Kernel::RBF);
+        $svm->setVarPath('var-path');
+    }
+
+    /**
+     * @expectedException \Phpml\Exception\InvalidArgumentException
+     * @expectedExceptionMessage does not exist
+     */
+    public function testThrowExceptionWhenBinPathDoesNotExist()
+    {
+        $svm = new SupportVectorMachine(Type::C_SVC, Kernel::RBF);
+        $svm->setBinPath('bin-path');
+    }
+
+    /**
+     * @expectedException \Phpml\Exception\InvalidArgumentException
+     * @expectedExceptionMessage not found
+     */
+    public function testThrowExceptionWhenFileIsNotFoundInBinPath()
+    {
+        $svm = new SupportVectorMachine(Type::C_SVC, Kernel::RBF);
+        $svm->setBinPath('var');
+    }
 }