Support newline parameter in FURB101 for Python 3.13+

crates/ruff_linter/resources/test/fixtures/refurb/FURB101_0.py

@@ -81,11 +81,11 @@ def bar(x):
 with open("file.txt", buffering=1) as f:
     x = f.read()
 
-# force CRLF, not supported in read_text()
+# FURB101 (newline is supported in read_text on Python 3.13+)
 with open("file.txt", newline="\r\n") as f:
     x = f.read()
 
-# dont mistake "newline" for "mode"
+# FURB101 (dont mistake "newline" for "mode")
 with open("file.txt", newline="b") as f:
     x = f.read()
 

crates/ruff_linter/resources/test/fixtures/refurb/FURB101_3.py

@@ -0,0 +1,13 @@
+# Tests for Python 3.13+ where `pathlib.Path.read_text` supports `newline`.
+
+# FURB101 (newline is supported in read_text on Python 3.13+)
+with open("file.txt", newline="\r\n") as f:
+    x = f.read()
+
+# FURB101 (newline with encoding)
+with open("file.txt", encoding="utf-8", newline="") as f:
+    x = f.read()
+
+# FURB101 (newline=None is also valid)
+with open("file.txt", newline=None) as f:
+    x = f.read()

crates/ruff_linter/src/rules/refurb/helpers.rs

@@ -366,10 +366,12 @@ fn match_open_keywords(
             "encoding" | "errors" => result.push(keyword),
             "newline" => {
                 if read_mode {
-                    // newline is only valid for write_text
-                    return None;
+                    if target_version < PythonVersion::PY313 {
+                        // `pathlib.Path.read_text` doesn't support `newline` until Python 3.13.
+                        return None;
+                    }
                 } else if target_version < PythonVersion::PY310 {
-                    // `pathlib` doesn't support `newline` until Python 3.10.
+                    // `pathlib.Path.write_text` doesn't support `newline` until Python 3.10.
                     return None;
                 }
 

crates/ruff_linter/src/rules/refurb/mod.rs

@@ -13,7 +13,7 @@ mod tests {
 
     use crate::registry::Rule;
     use crate::test::test_path;
-    use crate::{assert_diagnostics, settings};
+    use crate::{assert_diagnostics, assert_diagnostics_diff, settings};
 
     #[test_case(Rule::ReadWholeFile, Path::new("FURB101_0.py"))]
     #[test_case(Rule::ReadWholeFile, Path::new("FURB101_1.py"))]
@@ -66,6 +66,18 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn read_whole_file_newline_python_version_diff() -> Result<()> {
+        assert_diagnostics_diff!(
+            Path::new("refurb/FURB101_3.py"),
+            &settings::LinterSettings::for_rule(Rule::ReadWholeFile)
+                .with_target_version(PythonVersion::PY313),
+            &settings::LinterSettings::for_rule(Rule::ReadWholeFile)
+                .with_target_version(PythonVersion::PY312),
+        );
+        Ok(())
+    }
+
     #[test]
     fn write_whole_file_python_39() -> Result<()> {
         let diagnostics = test_path(

crates/ruff_linter/src/rules/refurb/snapshots/ruff_linter__rules__refurb__tests__FURB101_FURB101_0.py.snap

@@ -190,6 +190,54 @@ FURB101 `open` and `read` should be replaced by `Path("file.txt").read_text()`
    |
 help: Replace with `Path("file.txt").read_text()`
 
+FURB101 [*] `open` and `read` should be replaced by `Path("file.txt").read_text(newline="\r\n")`
+  --> FURB101_0.py:85:6
+   |
+84 | # FURB101 (newline is supported in read_text on Python 3.13+)
+85 | with open("file.txt", newline="\r\n") as f:
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+86 |     x = f.read()
+   |
+help: Replace with `Path("file.txt").read_text(newline="\r\n")`
+1  + import pathlib
+2  | def foo():
+3  |     ...
+4  | 
+--------------------------------------------------------------------------------
+83 |     x = f.read()
+84 | 
+85 | # FURB101 (newline is supported in read_text on Python 3.13+)
+   - with open("file.txt", newline="\r\n") as f:
+   -     x = f.read()
+86 + x = pathlib.Path("file.txt").read_text(newline="\r\n")
+87 | 
+88 | # FURB101 (dont mistake "newline" for "mode")
+89 | with open("file.txt", newline="b") as f:
+
+FURB101 [*] `open` and `read` should be replaced by `Path("file.txt").read_text(newline="b")`
+  --> FURB101_0.py:89:6
+   |
+88 | # FURB101 (dont mistake "newline" for "mode")
+89 | with open("file.txt", newline="b") as f:
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+90 |     x = f.read()
+   |
+help: Replace with `Path("file.txt").read_text(newline="b")`
+1  + import pathlib
+2  | def foo():
+3  |     ...
+4  | 
+--------------------------------------------------------------------------------
+87 |     x = f.read()
+88 | 
+89 | # FURB101 (dont mistake "newline" for "mode")
+   - with open("file.txt", newline="b") as f:
+   -     x = f.read()
+90 + x = pathlib.Path("file.txt").read_text(newline="b")
+91 | 
+92 | # I guess we can possibly also report this case, but the question
+93 | # is why the user would put "r+" here in the first place.
+
 FURB101 [*] `open` and `read` should be replaced by `Path("file.txt").read_text(encoding="utf-8")`
    --> FURB101_0.py:130:6
     |

crates/ruff_linter/src/rules/refurb/snapshots/ruff_linter__rules__refurb__tests__read_whole_file_newline_python_version_diff.snap

@@ -0,0 +1,81 @@
+---
+source: crates/ruff_linter/src/rules/refurb/mod.rs
+---
+--- Linter settings ---
+-linter.unresolved_target_version = 3.13
++linter.unresolved_target_version = 3.12
+
+--- Summary ---
+Removed: 3
+Added: 0
+
+--- Removed ---
+FURB101 [*] `open` and `read` should be replaced by `Path("file.txt").read_text(newline="\r\n")`
+ --> FURB101_3.py:4:6
+  |
+3 | # FURB101 (newline is supported in read_text on Python 3.13+)
+4 | with open("file.txt", newline="\r\n") as f:
+  |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+5 |     x = f.read()
+  |
+help: Replace with `Path("file.txt").read_text(newline="\r\n")`
+1 | # Tests for Python 3.13+ where `pathlib.Path.read_text` supports `newline`.
+2 | 
+3 | # FURB101 (newline is supported in read_text on Python 3.13+)
+  - with open("file.txt", newline="\r\n") as f:
+  -     x = f.read()
+4 + import pathlib
+5 + x = pathlib.Path("file.txt").read_text(newline="\r\n")
+6 | 
+7 | # FURB101 (newline with encoding)
+8 | with open("file.txt", encoding="utf-8", newline="") as f:
+
+
+FURB101 [*] `open` and `read` should be replaced by `Path("file.txt").read_text(encoding="utf-8", newline="")`
+ --> FURB101_3.py:8:6
+  |
+7 | # FURB101 (newline with encoding)
+8 | with open("file.txt", encoding="utf-8", newline="") as f:
+  |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+9 |     x = f.read()
+  |
+help: Replace with `Path("file.txt").read_text(encoding="utf-8", newline="")`
+1  | # Tests for Python 3.13+ where `pathlib.Path.read_text` supports `newline`.
+2  | 
+3  | # FURB101 (newline is supported in read_text on Python 3.13+)
+4  + import pathlib
+5  | with open("file.txt", newline="\r\n") as f:
+6  |     x = f.read()
+7  | 
+8  | # FURB101 (newline with encoding)
+   - with open("file.txt", encoding="utf-8", newline="") as f:
+   -     x = f.read()
+9  + x = pathlib.Path("file.txt").read_text(encoding="utf-8", newline="")
+10 | 
+11 | # FURB101 (newline=None is also valid)
+12 | with open("file.txt", newline=None) as f:
+
+
+FURB101 [*] `open` and `read` should be replaced by `Path("file.txt").read_text(newline=None)`
+  --> FURB101_3.py:12:6
+   |
+11 | # FURB101 (newline=None is also valid)
+12 | with open("file.txt", newline=None) as f:
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+13 |     x = f.read()
+   |
+help: Replace with `Path("file.txt").read_text(newline=None)`
+1  | # Tests for Python 3.13+ where `pathlib.Path.read_text` supports `newline`.
+2  | 
+3  | # FURB101 (newline is supported in read_text on Python 3.13+)
+4  + import pathlib
+5  | with open("file.txt", newline="\r\n") as f:
+6  |     x = f.read()
+7  | 
+--------------------------------------------------------------------------------
+10 |     x = f.read()
+11 | 
+12 | # FURB101 (newline=None is also valid)
+   - with open("file.txt", newline=None) as f:
+   -     x = f.read()
+13 + x = pathlib.Path("file.txt").read_text(newline=None)