add test that asserts utf8 fields if no inference of schema is done i…

…n csv
pola-rs · Nov 16, 2021 · 4ac3ec9 · 4ac3ec9
1 parent fb361c4
commit 4ac3ec9
Showing 1 changed file with 20 additions and 0 deletions.
diff --git a/polars/polars-io/src/csv.rs b/polars/polars-io/src/csv.rs
@@ -1290,4 +1290,24 @@ A3,\"B4_\"\"with_embedded_double_quotes\"\"\",C4,4";
 
         Ok(())
     }
+
+    #[test]
+    fn test_infer_schema_0_rows() -> Result<()> {
+        let csv = r#"a,b,c,d
+1,a,1.0,true
+1,a,1.0,false
+"#;
+        let file = Cursor::new(csv);
+        let df = CsvReader::new(file).infer_schema(Some(0)).finish()?;
+        assert_eq!(
+            df.dtypes(),
+            &[
+                DataType::Utf8,
+                DataType::Utf8,
+                DataType::Utf8,
+                DataType::Utf8
+            ]
+        );
+        Ok(())
+    }
 }