[pycodestyle] - add autofix for multiple_imports_on_one_line (`E4…

…01`)

crates/ruff_linter/resources/test/fixtures/pycodestyle/E40.py

@@ -1,5 +1,12 @@
 #: E401
 import os, sys
+import re as regex, string  # also with a comment!
+
+def blah():
+    import datetime as dt, copy 
+    def nested_and_tested():
+        import builtins, textwrap as tw
+
 #: Okay
 import os
 import sys

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

@@ -67,6 +67,7 @@ mod tests {
     }
 
     #[test_case(Rule::IsLiteral, Path::new("constant_literals.py"))]
+    #[test_case(Rule::MultipleImportsOnOneLine, Path::new("E40.py"))]
     #[test_case(Rule::ModuleImportNotAtTopOfFile, Path::new("E402_0.py"))]
     #[test_case(Rule::TypeComparison, Path::new("E721.py"))]
     fn preview_rules(rule_code: Rule, path: &Path) -> Result<()> {

crates/ruff_linter/src/rules/pycodestyle/rules/imports.rs

@@ -1,6 +1,7 @@
-use ruff_diagnostics::{Diagnostic, Violation};
+use ruff_diagnostics::{AlwaysFixableViolation, Diagnostic, Edit, Fix, Violation};
 use ruff_macros::{derive_message_formats, violation};
 use ruff_python_ast::{Alias, PySourceType, Stmt};
+use ruff_python_trivia::{indentation_at_offset, PythonWhitespace};
 use ruff_text_size::Ranged;
 
 use crate::checkers::ast::Checker;
@@ -26,11 +27,15 @@ use crate::checkers::ast::Checker;
 #[violation]
 pub struct MultipleImportsOnOneLine;
 
-impl Violation for MultipleImportsOnOneLine {
+impl AlwaysFixableViolation for MultipleImportsOnOneLine {
     #[derive_message_formats]
     fn message(&self) -> String {
         format!("Multiple imports on one line")
     }
+
+    fn fix_title(&self) -> String {
+        format!("Split imports onto multiple lines")
+    }
 }
 
 /// ## What it does
@@ -85,9 +90,40 @@ impl Violation for ModuleImportNotAtTopOfFile {
 /// E401
 pub(crate) fn multiple_imports_on_one_line(checker: &mut Checker, stmt: &Stmt, names: &[Alias]) {
     if names.len() > 1 {
-        checker
-            .diagnostics
-            .push(Diagnostic::new(MultipleImportsOnOneLine, stmt.range()));
+        let mut diagnostic = Diagnostic::new(MultipleImportsOnOneLine, stmt.range());
+
+        if checker.settings.preview.is_enabled() {
+            let indentation = indentation_at_offset(stmt.start(), checker.locator()).unwrap_or("");
+
+            let mut replacement = String::new();
+
+            for item in names {
+                let Alias {
+                    range: _,
+                    name,
+                    asname,
+                } = item;
+
+                if let Some(asname) = asname {
+                    replacement = format!("{replacement}{indentation}import {name} as {asname}\n",);
+                } else {
+                    replacement = format!("{replacement}{indentation}import {name}\n",);
+                }
+            }
+
+            // remove leading whitespace because we start at the import keyword
+            replacement = replacement.trim_whitespace_start().to_string();
+
+            // remove trailing newline
+            replacement = replacement.trim_end_matches('\n').to_string();
+
+            diagnostic.set_fix(Fix::safe_edit(Edit::range_replacement(
+                replacement,
+                stmt.range(),
+            )));
+        }
+
+        checker.diagnostics.push(diagnostic);
     }
 }
 

crates/ruff_linter/src/rules/pycodestyle/snapshots/ruff_linter__rules__pycodestyle__tests__E402_E40.py.snap

@@ -1,31 +1,156 @@
 ---
 source: crates/ruff_linter/src/rules/pycodestyle/mod.rs
 ---
-E40.py:55:1: E402 Module level import not at top of file
+E40.py:11:1: E402 Module level import not at top of file
    |
-53 | VERSION = '1.2.3'
-54 | 
-55 | import foo
+10 | #: Okay
+11 | import os
+   | ^^^^^^^^^ E402
+12 | import sys
+   |
+
+E40.py:12:1: E402 Module level import not at top of file
+   |
+10 | #: Okay
+11 | import os
+12 | import sys
+   | ^^^^^^^^^^ E402
+13 | 
+14 | from subprocess import Popen, PIPE
+   |
+
+E40.py:14:1: E402 Module level import not at top of file
+   |
+12 | import sys
+13 | 
+14 | from subprocess import Popen, PIPE
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ E402
+15 | 
+16 | from myclass import MyClass
+   |
+
+E40.py:16:1: E402 Module level import not at top of file
+   |
+14 | from subprocess import Popen, PIPE
+15 | 
+16 | from myclass import MyClass
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ E402
+17 | from foo.bar.yourclass import YourClass
+   |
+
+E40.py:17:1: E402 Module level import not at top of file
+   |
+16 | from myclass import MyClass
+17 | from foo.bar.yourclass import YourClass
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ E402
+18 | 
+19 | import myclass
+   |
+
+E40.py:19:1: E402 Module level import not at top of file
+   |
+17 | from foo.bar.yourclass import YourClass
+18 | 
+19 | import myclass
+   | ^^^^^^^^^^^^^^ E402
+20 | import foo.bar.yourclass
+21 | #: Okay
+   |
+
+E40.py:20:1: E402 Module level import not at top of file
+   |
+19 | import myclass
+20 | import foo.bar.yourclass
+   | ^^^^^^^^^^^^^^^^^^^^^^^^ E402
+21 | #: Okay
+22 | __all__ = ['abc']
+   |
+
+E40.py:24:1: E402 Module level import not at top of file
+   |
+22 | __all__ = ['abc']
+23 | 
+24 | import foo
+   | ^^^^^^^^^^ E402
+25 | #: Okay
+26 | __version__ = "42"
+   |
+
+E40.py:28:1: E402 Module level import not at top of file
+   |
+26 | __version__ = "42"
+27 | 
+28 | import foo
+   | ^^^^^^^^^^ E402
+29 | #: Okay
+30 | __author__ = "Simon Gomizelj"
+   |
+
+E40.py:32:1: E402 Module level import not at top of file
+   |
+30 | __author__ = "Simon Gomizelj"
+31 | 
+32 | import foo
+   | ^^^^^^^^^^ E402
+33 | #: Okay
+34 | try:
+   |
+
+E40.py:43:1: E402 Module level import not at top of file
+   |
+41 |     print('made attempt to import foo')
+42 | 
+43 | import bar
+   | ^^^^^^^^^^ E402
+44 | #: Okay
+45 | with warnings.catch_warnings():
+   |
+
+E40.py:49:1: E402 Module level import not at top of file
+   |
+47 |     import foo
+48 | 
+49 | import bar
+   | ^^^^^^^^^^ E402
+50 | #: Okay
+51 | if False:
+   |
+
+E40.py:58:1: E402 Module level import not at top of file
+   |
+56 |     import mwahaha
+57 | 
+58 | import bar
+   | ^^^^^^^^^^ E402
+59 | #: E402
+60 | VERSION = '1.2.3'
+   |
+
+E40.py:62:1: E402 Module level import not at top of file
+   |
+60 | VERSION = '1.2.3'
+61 | 
+62 | import foo
    | ^^^^^^^^^^ E402
-56 | #: E402
-57 | import foo
+63 | #: E402
+64 | import foo
    |
 
-E40.py:57:1: E402 Module level import not at top of file
+E40.py:64:1: E402 Module level import not at top of file
    |
-55 | import foo
-56 | #: E402
-57 | import foo
+62 | import foo
+63 | #: E402
+64 | import foo
    | ^^^^^^^^^^ E402
-58 | 
-59 | a = 1
+65 | 
+66 | a = 1
    |
 
-E40.py:61:1: E402 Module level import not at top of file
+E40.py:68:1: E402 Module level import not at top of file
    |
-59 | a = 1
-60 | 
-61 | import bar
+66 | a = 1
+67 | 
+68 | import bar
    | ^^^^^^^^^^ E402
    |
 

crates/ruff_linter/src/rules/pycodestyle/snapshots/ruff_linter__rules__pycodestyle__tests__preview__E401_E40.py.snap

@@ -0,0 +1,86 @@
+---
+source: crates/ruff_linter/src/rules/pycodestyle/mod.rs
+---
+E40.py:2:1: E401 [*] Multiple imports on one line
+  |
+1 | #: E401
+2 | import os, sys
+  | ^^^^^^^^^^^^^^ E401
+3 | import re as regex, string  # also with a comment!
+  |
+  = help: Split imports onto multiple lines
+
+ℹ Safe fix
+1 1 | #: E401
+2   |-import os, sys
+  2 |+import os
+  3 |+import sys
+3 4 | import re as regex, string  # also with a comment!
+4 5 | 
+5 6 | def blah():
+
+E40.py:3:1: E401 [*] Multiple imports on one line
+  |
+1 | #: E401
+2 | import os, sys
+3 | import re as regex, string  # also with a comment!
+  | ^^^^^^^^^^^^^^^^^^^^^^^^^^ E401
+4 | 
+5 | def blah():
+  |
+  = help: Split imports onto multiple lines
+
+ℹ Safe fix
+1 1 | #: E401
+2 2 | import os, sys
+3   |-import re as regex, string  # also with a comment!
+  3 |+import re as regex
+  4 |+import string  # also with a comment!
+4 5 | 
+5 6 | def blah():
+6 7 |     import datetime as dt, copy 
+
+E40.py:6:5: E401 [*] Multiple imports on one line
+  |
+5 | def blah():
+6 |     import datetime as dt, copy 
+  |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ E401
+7 |     def nested_and_tested():
+8 |         import builtins, textwrap as tw
+  |
+  = help: Split imports onto multiple lines
+
+ℹ Safe fix
+3 3 | import re as regex, string  # also with a comment!
+4 4 | 
+5 5 | def blah():
+6   |-    import datetime as dt, copy 
+  6 |+    import datetime as dt
+  7 |+    import copy 
+7 8 |     def nested_and_tested():
+8 9 |         import builtins, textwrap as tw
+9 10 | 
+
+E40.py:8:9: E401 [*] Multiple imports on one line
+   |
+ 6 |     import datetime as dt, copy 
+ 7 |     def nested_and_tested():
+ 8 |         import builtins, textwrap as tw
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ E401
+ 9 | 
+10 | #: Okay
+   |
+   = help: Split imports onto multiple lines
+
+ℹ Safe fix
+5  5  | def blah():
+6  6  |     import datetime as dt, copy 
+7  7  |     def nested_and_tested():
+8     |-        import builtins, textwrap as tw
+   8  |+        import builtins
+   9  |+        import textwrap as tw
+9  10 | 
+10 11 | #: Okay
+11 12 | import os
+
+