Adds the option to throw an exception on missing parameters in non-in…

…teractive mode Incenteev#105

Processor.php

@@ -104,7 +104,7 @@ private function processParams(array $config, array $expectedParams, array $actu
         // Add the params coming from the environment values
         $actualParams = array_replace($actualParams, $this->getEnvValues($envMap));
 
-        return $this->getParams($expectedParams, $actualParams);
+        return $this->getParams($config, $expectedParams, $actualParams);
     }
 
     private function getEnvValues(array $envMap)
@@ -137,10 +137,20 @@ private function processRenamedValues(array $renameMap, array $actualParams)
         return $actualParams;
     }
 
-    private function getParams(array $expectedParams, array $actualParams)
+    private function getParams(array $config, array $expectedParams, array $actualParams)
     {
-        // Simply use the expectedParams value as default for the missing params.
         if (!$this->io->isInteractive()) {
+            if (isset($config['exception-when-missing'])) {
+                foreach ($expectedParams as $key => $message) {
+                    if (array_key_exists($key, $actualParams)) {
+                        continue;
+                    }
+
+                    throw new \InvalidArgumentException(sprintf('Some parameters are missing. Please provide them. Missing %s', $key));
+                }
+            }
+
+            // Simply use the expectedParams value as default for the missing params.
             return array_replace($expectedParams, $actualParams);
         }
 

README.md

@@ -60,7 +60,18 @@ in the parameters file, using the value of the dist file as default value.
 All prompted values are parsed as inline Yaml, to allow you to define ``true``,
 ``false``, ``null`` or numbers easily.
 If composer is run in a non-interactive mode, the values of the dist file
-will be used for missing parameters.
+will be used for missing parameters, unless the ``exception-when-missing`` is set
+in the configuration, then an exception is thrown. Example:
+
+```json
+{
+    "extra": {
+        "incenteev-parameters": {
+            "exception-when-missing": true
+        }
+    }
+}
+```
 
 **Warning:** This parameters handler will overwrite any comments or spaces into
 your parameters.yml file so handle with care. If you want to give format