handle file content that does not end with curly brace (#303)

(cherry picked from commit 9602441)

Author: hauner

openapi-processor-core/src/main/kotlin/io/openapiprocessor/core/writer/java/GoogleFormatter.kt

@@ -34,6 +34,9 @@ open class GoogleFormatter: SourceFormatter {
     // put line feed before last closing }
     private fun correctLineFeed(formatted: String): String {
         val index = formatted.lastIndexOf("}")
+        if (index == -1) {
+            return formatted
+        }
 
         return StringBuilder()
             .append(formatted.substring(0, index))

openapi-processor-core/src/test/kotlin/io/openapiprocessor/core/writer/java/GoogleFormatterSpec.kt

@@ -38,4 +38,22 @@ class GoogleFormatterSpec : StringSpec({
             formatter.format("....")
         }
     }
+
+    "does handle package-info.java, no closing curly brace" {
+        val formatter = GoogleFormatter()
+
+        formatter.format(
+            """
+               | @org.springframework.lang.NonNullApi
+               |@org.springframework.lang.NonNullFields
+               | package  generated.spring;
+               | 
+            """.trimMargin()
+        ) shouldBe """
+               |@org.springframework.lang.NonNullApi
+               |@org.springframework.lang.NonNullFields
+               |package generated.spring;
+               |
+            """.trimMargin()
+    }
 })