bug[rust]: Fix float display (#4840)

pola-rs · Sep 13, 2022 · 3dcb2ad · 3dcb2ad
1 parent e2edab3
commit 3dcb2ad
Show file tree

Hide file tree

Showing 3 changed files with 112 additions and 82 deletions.
diff --git a/polars/polars-core/src/fmt.rs b/polars/polars-core/src/fmt.rs
@@ -483,8 +483,8 @@ fn fmt_float<T: Num + NumCast>(f: &mut Formatter<'_>, width: usize, v: T) -> fmt
                 let mut len = s.len() - 1;
 
                 while s.ends_with('0') {
-                    len -= 1;
                     s = &s[..len];
+                    len -= 1;
                 }
                 if s.ends_with('.') {
                     write!(f, "{}0", s)
@@ -837,73 +837,4 @@ ChunkedArray: 'name' [str]
             format!("{:?}", ca)
         );
     }
-
-    #[test]
-    fn test_fmt_series() {
-        let s = Series::new("foo", &["Somelongstringto eeat wit me oundaf"]);
-        assert_eq!(
-            r#"shape: (1,)
-Series: 'foo' [str]
-[
-	"Somelongstring...
-]"#,
-            format!("{:?}", s)
-        );
-
-        let s = Series::new("foo", &["😀😁😂😃😄😅😆😇😈😉😊😋😌😎😏😐😑😒😓"]);
-        assert_eq!(
-            r#"shape: (1,)
-Series: 'foo' [str]
-[
-	"😀😁😂😃😄😅😆😇😈😉😊😋😌😎...
-]"#,
-            format!("{:?}", s)
-        );
-
-        let s = Series::new("foo", &["yzäöüäöüäöüäö"]);
-        assert_eq!(
-            r#"shape: (1,)
-Series: 'foo' [str]
-[
-	"yzäöüäöüäöüäö"
-]"#,
-            format!("{:?}", s)
-        );
-
-        let s = Series::new("foo", (0..100).collect::<Vec<_>>());
-
-        dbg!(&s);
-        assert_eq!(
-            r#"shape: (100,)
-Series: 'foo' [i32]
-[
-	0
-	1
-	2
-	3
-	4
-	5
-	6
-	7
-	8
-	9
-	10
-	11
-	...
-	88
-	89
-	90
-	91
-	92
-	93
-	94
-	95
-	96
-	97
-	98
-	99
-]"#,
-            format!("{:?}", s)
-        );
-    }
 }
diff --git a/py-polars/polars/internals/expr/expr.py b/py-polars/polars/internals/expr/expr.py
@@ -388,17 +388,17 @@ def log10(self) -> Expr:
         >>> df = pl.DataFrame({"values": [1.0, 2.0, 4.0]})
         >>> df.select(pl.col("values").log10())
         shape: (3, 1)
-        ┌────────┐
-        │ values │
-        │ ---    │
-        │ f64    │
-        ╞════════╡
-        │ 0.0    │
-        ├╌╌╌╌╌╌╌╌┤
-        │ 0.301  │
-        ├╌╌╌╌╌╌╌╌┤
-        │ 0.602  │
-        └────────┘
+        ┌─────────┐
+        │ values  │
+        │ ---     │
+        │ f64     │
+        ╞═════════╡
+        │ 0.0     │
+        ├╌╌╌╌╌╌╌╌╌┤
+        │ 0.30103 │
+        ├╌╌╌╌╌╌╌╌╌┤
+        │ 0.60206 │
+        └─────────┘
 
         """
         return self.log(10.0)
@@ -421,7 +421,7 @@ def exp(self) -> Expr:
         ├╌╌╌╌╌╌╌╌╌╌┤
         │ 7.389056 │
         ├╌╌╌╌╌╌╌╌╌╌┤
-        │ 54.5981  │
+        │ 54.59815 │
         └──────────┘
 
         """

diff --git a/py-polars/tests/unit/test_fmt.py b/py-polars/tests/unit/test_fmt.py
@@ -0,0 +1,99 @@
+from typing import Any, List
+
+import pytest
+
+import polars as pl
+
+
+@pytest.mark.parametrize(
+    "expected, values",
+    [
+        pytest.param(
+            """shape: (1,)
+Series: 'foo' [str]
+[
+	"Somelongstring...
+]
+""",  # noqa: W191, E101
+            ["Somelongstringto eeat wit me oundaf"],
+            id="Long string",
+        ),
+        pytest.param(
+            """shape: (1,)
+Series: 'foo' [str]
+[
+	"😀😁😂😃😄😅😆😇😈😉😊😋😌😎...
+]
+""",  # noqa: W191, E101
+            ["😀😁😂😃😄😅😆😇😈😉😊😋😌😎😏😐😑😒😓"],
+            id="Emojis",
+        ),
+        pytest.param(
+            """shape: (1,)
+Series: 'foo' [str]
+[
+	"yzäöüäöüäöüäö"
+]
+""",  # noqa: W191, E101
+            ["yzäöüäöüäöüäö"],
+            id="Characters with accents",
+        ),
+        pytest.param(
+            """shape: (100,)
+Series: 'foo' [i64]
+[
+	0
+	1
+	2
+	3
+	4
+	5
+	6
+	7
+	8
+	9
+	10
+	11
+	...
+	88
+	89
+	90
+	91
+	92
+	93
+	94
+	95
+	96
+	97
+	98
+	99
+]
+""",  # noqa: W191, E101
+            [*range(100)],
+            id="Long series",
+        ),
+    ],
+)
+def test_fmt_series(
+    capfd: pytest.CaptureFixture[str], expected: str, values: List[Any]
+) -> None:
+    s = pl.Series(name="foo", values=values)
+    print(s)
+    out, err = capfd.readouterr()
+    assert out == expected
+
+
+def test_fmt_float(capfd: pytest.CaptureFixture[str]) -> None:
+    s = pl.Series(name="foo", values=[7.966e-05, 7.9e-05, 8.4666e-05, 8.00007966])
+    print(s)
+    out, err = capfd.readouterr()
+    expected = """shape: (4,)
+Series: 'foo' [f64]
+[
+	0.00008
+	0.000079
+	0.000085
+	8.00008
+]
+"""  # noqa: W191, E101
+    assert out == expected