Fix NPE in ksp processing (#862) (#865)

### Overview
The `containingFile` of `KSClassDeclaration` is nullable. Update the
processing to handle a null containingFile.

I was able to pull, modify, and build the project artifacts. This change
fixes the NullPointerException (my local project build now fully
completes) and I am able to see the generated Q entities from the
external library. Both my Child class entity and Parent Entity in the
external library are generated.

### Testing
Run build to completion (`mvn -Pquickbuild,all clean install`), pulled
in artifacts to my project, built & ran without issues.

### Note
Please let me know if `master` is the correct branch to get a quick fix
out. Thanks!

querydsl-tooling/querydsl-ksp-codegen/src/main/kotlin/com/querydsl/ksp/codegen/QueryDslProcessor.kt

@@ -36,7 +36,7 @@ class QueryDslProcessor(
                 .writeTo(
                     codeGenerator = codeGenerator,
                     aggregating = false,
-                    originatingKSFiles = listOf(model.originatingFile)
+                    originatingKSFiles = listOfNotNull(model.originatingFile)
                 )
         }
     }

querydsl-tooling/querydsl-ksp-codegen/src/main/kotlin/com/querydsl/ksp/codegen/QueryModel.kt

@@ -8,7 +8,7 @@ class QueryModel(
     val typeParameterCount: Int,
     val className: ClassName,
     val type: QueryModelType,
-    val originatingFile: KSFile
+    val originatingFile: KSFile?
 ) {
     var superclass: QueryModel? = null
 

querydsl-tooling/querydsl-ksp-codegen/src/main/kotlin/com/querydsl/ksp/codegen/QueryModelExtractor.kt

@@ -112,7 +112,7 @@ class QueryModelExtractor(
             typeParameterCount = classDeclaration.typeParameters.size,
             className = queryClassName(classDeclaration, settings),
             type = type,
-            originatingFile = classDeclaration.containingFile!!
+            originatingFile = classDeclaration.containingFile
         )
     }
 

querydsl-tooling/querydsl-ksp-codegen/src/test/kotlin/RenderTest.kt

@@ -72,6 +72,30 @@ class RenderTest {
         code.assertContainLines("val _super: QAnimal by lazy { QAnimal(this) }")
     }
 
+    @Test
+    fun superclassNullContainingFile() {
+        val model = QueryModel(
+            originalClassName = ClassName("", "Cat"),
+            typeParameterCount = 0,
+            className = ClassName("", "QCat"),
+            type = QueryModelType.ENTITY,
+            mockk()
+        )
+        val superClass = QueryModel(
+            originalClassName = ClassName("", "Animal"),
+            typeParameterCount = 0,
+            className = ClassName("", "QAnimal"),
+            type = QueryModelType.SUPERCLASS,
+            null
+        )
+        model.superclass = superClass
+        val typeSpec = QueryModelRenderer.render(model)
+        val code = typeSpec.toString()
+        code.assertCompiles()
+        code.assertContains("class QCat : com.querydsl.core.types.dsl.EntityPathBase<Cat>")
+        code.assertContainLines("val _super: QAnimal by lazy { QAnimal(this) }")
+    }
+
     @Test
     fun genericTypeArgs() {
         val model = QueryModel(