LSlog: fix computing exception context

src/includes/class/class.LSlog.php

@@ -401,13 +401,12 @@ class LSlog {
    * @return void
    **/
   public static function exception($exception, $prefix=null, $fatal=true, $logger=null) {
-    $message =
-      ($prefix?"$prefix :\n":"An exception occured :\n").
-      implode(
-        "\n",
-        array_map(
-          function($line) { return "  $line"; },
-          array_slice(
+    $message = sprintf("%s:\n", $prefix ? $prefix : "An exception occured");
+
+    // Add backtrace
+    // Note: reverse the backtrace lines to get the entrypoint as first and remove useless first
+    // "{main}" line.
+    $lines = array_slice(
       array_reverse(
         explode(
           "\n",
@@ -416,9 +415,21 @@ class LSlog {
         1
       ),
       1
-          )
-        )
-      )."\n    => ". $exception->getMessage();
+    );
+    foreach($lines as $idx => $line)
+      $message .= sprintf(
+        "  #%d %s\n",
+        $idx + 1,
+        substr($line, 2)
+      );
+
+    // Add exception details
+    $message .= sprintf(
+      "  #0  %s(%s) :\n    => %s",
+      $exception->getFile(),
+      $exception->getLine(),
+      $exception->getMessage()
+    );
     self :: logging(($fatal?'FATAL':'ERROR'), $message, $logger, true);
   }