test(datafusion): cover the factory's one-location check; fix fork branch notes

Cargo.toml

@@ -166,7 +166,7 @@ zstd = "0.13.3"
 # Spice links iceberg-rust against its arrow-rs and DataFusion forks, so the tests here run
 # against the same forks.
 [patch.crates-io]
-# arrow-rs 59.3.0 with Spice patches — branch: spiceai-59-patches
+# arrow-rs 59.3.0 with Spice patches — branch: spiceai-59
 arrow = { git = "https://github.com/spiceai/arrow-rs.git", rev = "2e2cc330c64ac8a9e44d2a5f2da171b391f775b8" }
 arrow-arith = { git = "https://github.com/spiceai/arrow-rs.git", rev = "2e2cc330c64ac8a9e44d2a5f2da171b391f775b8" }
 arrow-array = { git = "https://github.com/spiceai/arrow-rs.git", rev = "2e2cc330c64ac8a9e44d2a5f2da171b391f775b8" }
@@ -185,7 +185,7 @@ arrow-select = { git = "https://github.com/spiceai/arrow-rs.git", rev = "2e2cc33
 arrow-string = { git = "https://github.com/spiceai/arrow-rs.git", rev = "2e2cc330c64ac8a9e44d2a5f2da171b391f775b8" }
 parquet = { git = "https://github.com/spiceai/arrow-rs.git", rev = "2e2cc330c64ac8a9e44d2a5f2da171b391f775b8" }
 
-# DataFusion 55.1.0 with Spice patches — branch: spiceai-55-patches
+# DataFusion 55.1.0 with Spice patches — branch: spiceai-55
 datafusion = { git = "https://github.com/spiceai/datafusion.git", rev = "02550cf9462b9f56506b6b1cd07eabf08c46e200" }
 datafusion-catalog = { git = "https://github.com/spiceai/datafusion.git", rev = "02550cf9462b9f56506b6b1cd07eabf08c46e200" }
 datafusion-catalog-listing = { git = "https://github.com/spiceai/datafusion.git", rev = "02550cf9462b9f56506b6b1cd07eabf08c46e200" }

crates/integrations/datafusion/src/table/table_provider_factory.rs

@@ -298,6 +298,52 @@ mod tests {
         assert_eq!(actual_schema.as_ref(), &expected_schema);
     }
 
+    #[tokio::test]
+    async fn test_create_rejects_zero_locations() {
+        let factory = IcebergTableProviderFactory::new();
+
+        let state = SessionStateBuilder::new().build();
+        let cmd = CreateExternalTable {
+            locations: vec![],
+            ..create_external_table_cmd()
+        };
+
+        let error = factory
+            .create(&state, &cmd)
+            .await
+            .expect_err("a command without a location should be rejected");
+
+        assert!(
+            error
+                .to_string()
+                .contains("exactly one metadata file location, got 0"),
+            "unexpected error: {error}"
+        );
+    }
+
+    #[tokio::test]
+    async fn test_create_rejects_multiple_locations() {
+        let factory = IcebergTableProviderFactory::new();
+
+        let state = SessionStateBuilder::new().build();
+        let cmd = CreateExternalTable {
+            locations: vec![table_metadata_location(), table_metadata_location()],
+            ..create_external_table_cmd()
+        };
+
+        let error = factory
+            .create(&state, &cmd)
+            .await
+            .expect_err("a command with several locations should be rejected");
+
+        assert!(
+            error
+                .to_string()
+                .contains("exactly one metadata file location, got 2"),
+            "unexpected error: {error}"
+        );
+    }
+
     #[tokio::test]
     async fn test_schema_of_created_external_table_sql() {
         let mut state = SessionStateBuilder::new().with_default_features().build();