check flags on schema view init

src/nanoarrow/schema.c

@@ -1178,16 +1178,32 @@ ArrowErrorCode ArrowSchemaViewInit(struct ArrowSchemaView* schema_view,
     schema_view->type = NANOARROW_TYPE_DICTIONARY;
   }
 
-  result = ArrowSchemaViewValidate(schema_view, schema_view->storage_type, error);
-  if (result != NANOARROW_OK) {
-    return result;
-  }
+  NANOARROW_RETURN_NOT_OK(
+      ArrowSchemaViewValidate(schema_view, schema_view->storage_type, error));
 
   if (schema_view->storage_type != schema_view->type) {
-    result = ArrowSchemaViewValidate(schema_view, schema_view->type, error);
-    if (result != NANOARROW_OK) {
-      return result;
-    }
+    NANOARROW_RETURN_NOT_OK(
+        ArrowSchemaViewValidate(schema_view, schema_view->type, error));
+  }
+
+  int64_t unknown_flags = schema->flags & ~ARROW_FLAG_DICTIONARY_ORDERED &
+                          ~ARROW_FLAG_NULLABLE & ~ARROW_FLAG_MAP_KEYS_SORTED;
+  if (unknown_flags != 0) {
+    ArrowErrorSet(error, "Unknown ArrowSchema flag");
+    return EINVAL;
+  }
+
+  if (schema->flags & ARROW_FLAG_DICTIONARY_ORDERED &&
+      schema_view->type != NANOARROW_TYPE_DICTIONARY) {
+    ArrowErrorSet(error,
+                  "ARROW_FLAG_DICTIONARY_ORDERED is only relevant for dictionaries");
+    return EINVAL;
+  }
+
+  if (schema->flags & ARROW_FLAG_MAP_KEYS_SORTED &&
+      schema_view->type != NANOARROW_TYPE_MAP) {
+    ArrowErrorSet(error, "ARROW_FLAG_MAP_KEYS_SORTED is only relevant for a map type");
+    return EINVAL;
   }
 
   ArrowLayoutInit(&schema_view->layout, schema_view->storage_type);

src/nanoarrow/schema_test.cc

@@ -574,6 +574,24 @@ TEST(SchemaViewTest, SchemaViewInitErrors) {
   EXPECT_STREQ(ArrowErrorMessage(&error),
                "Error parsing schema->format 'n*': parsed 1/2 characters");
 
+  ASSERT_EQ(ArrowSchemaSetFormat(&schema, "n"), NANOARROW_OK);
+  schema.flags = 0;
+  schema.flags |= ARROW_FLAG_DICTIONARY_ORDERED;
+  EXPECT_EQ(ArrowSchemaViewInit(&schema_view, &schema, &error), EINVAL);
+  EXPECT_STREQ(ArrowErrorMessage(&error),
+               "ARROW_FLAG_DICTIONARY_ORDERED is only relevant for dictionaries");
+
+  schema.flags = 0;
+  schema.flags |= ARROW_FLAG_MAP_KEYS_SORTED;
+  EXPECT_EQ(ArrowSchemaViewInit(&schema_view, &schema, &error), EINVAL);
+  EXPECT_STREQ(ArrowErrorMessage(&error),
+               "ARROW_FLAG_MAP_KEYS_SORTED is only relevant for a map type");
+
+  schema.flags = 0;
+  schema.flags |= (ARROW_FLAG_MAP_KEYS_SORTED << 1);
+  EXPECT_EQ(ArrowSchemaViewInit(&schema_view, &schema, &error), EINVAL);
+  EXPECT_STREQ(ArrowErrorMessage(&error), "Unknown ArrowSchema flag");
+
   ArrowSchemaRelease(&schema);
 }