undefined offset fix (#19406)

src/Symfony/Component/Console/Helper/Table.php

@@ -101,11 +101,11 @@ class Table
             self::$styles = self::initStyles();
         }
 
-        if (!self::$styles[$name]) {
-            throw new \InvalidArgumentException(sprintf('Style "%s" is not defined.', $name));
+        if (isset(self::$styles[$name])) {
+            return self::$styles[$name];
         }
 
-        return self::$styles[$name];
+        throw new \InvalidArgumentException(sprintf('Style "%s" is not defined.', $name));
     }
 
     /**
@@ -117,13 +117,7 @@ class Table
      */
     public function setStyle($name)
     {
-        if ($name instanceof TableStyle) {
-            $this->style = $name;
-        } elseif (isset(self::$styles[$name])) {
-            $this->style = self::$styles[$name];
-        } else {
-            throw new \InvalidArgumentException(sprintf('Style "%s" is not defined.', $name));
-        }
+        $this->style = $this->resolveStyle($name);
 
         return $this;
     }
@@ -611,4 +605,17 @@ class Table
             'symfony-style-guide' => $styleGuide,
         );
     }
+
+    private function resolveStyle($name)
+    {
+        if ($name instanceof TableStyle) {
+            return $name;
+        }
+
+        if (isset(self::$styles[$name])) {
+            return self::$styles[$name];
+        }
+
+        throw new \InvalidArgumentException(sprintf('Style "%s" is not defined.', $name));
+    }
 }

src/Symfony/Component/Console/Tests/Helper/TableTest.php

@@ -577,6 +577,25 @@ TABLE;
         $this->assertEquals($table, $table->addRow(new TableSeparator()), 'fluent interface on addRow() with a single TableSeparator() works');
     }
 
+    /**
+     * @expectedException \InvalidArgumentException
+     * @expectedExceptionMessage Style "absent" is not defined.
+     */
+    public function testIsNotDefinedStyleException()
+    {
+        $table = new Table($this->getOutputStream());
+        $table->setStyle('absent');
+    }
+
+    /**
+     * @expectedException \InvalidArgumentException
+     * @expectedExceptionMessage Style "absent" is not defined.
+     */
+    public function testGetStyleDefinition()
+    {
+        Table::getStyleDefinition('absent');
+    }
+
     protected function getOutputStream()
     {
         return new StreamOutput($this->stream, StreamOutput::VERBOSITY_NORMAL, false);