fix PLC2701 false positive for dunder submodules and improve diagnostic ranges

Author: Jkhall81

crates/ruff_linter/src/rules/pylint/rules/import_private_name.rs

@@ -116,7 +116,9 @@ pub(crate) fn import_private_name(checker: &Checker, scope: &Scope) {
             .qualified_name
             .segments()
             .iter()
-            .find_position(|name| name.starts_with('_'))
+            .find_position(|name| {
+                name.starts_with('_') && !(name.starts_with("__") && name.ends_with("__"))
+            })
         else {
             continue;
         };
@@ -137,7 +139,25 @@ pub(crate) fn import_private_name(checker: &Checker, scope: &Scope) {
         } else {
             None
         };
-        checker.report_diagnostic(ImportPrivateName { name, module }, binding.range());
+        let range = match binding.source.map(|id| checker.semantic().statement(id)) {
+            Some(ruff_python_ast::Stmt::ImportFrom(import_from)) => {
+                if index < import_info.module_name.len() {
+                    import_from
+                        .module
+                        .as_ref()
+                        .map_or(binding.range(), |m| m.range())
+                } else {
+                    import_from
+                        .names
+                        .iter()
+                        .find(|alias| alias.name.as_str() == import_info.member_name)
+                        .map_or(binding.range(), |alias| alias.range())
+                }
+            }
+            _ => binding.range(),
+        };
+
+        checker.report_diagnostic(ImportPrivateName { name, module }, range);
     }
 }
 

crates/ruff_linter/src/rules/pylint/snapshots/ruff_linter__rules__pylint__tests__PLC2701_import_private_name__submodule____main__.py.snap

@@ -2,33 +2,33 @@
 source: crates/ruff_linter/src/rules/pylint/mod.rs
 ---
 PLC2701 Private name import `_a`
- --> __main__.py:2:16
+ --> __main__.py:2:6
   |
 1 | # Errors.
 2 | from _a import b
-  |                ^
+  |      ^^
 3 | from c._d import e
 4 | from _f.g import h
   |
 
 PLC2701 Private name import `_d` from external module `c`
- --> __main__.py:3:18
+ --> __main__.py:3:6
   |
 1 | # Errors.
 2 | from _a import b
 3 | from c._d import e
-  |                  ^
+  |      ^^^^
 4 | from _f.g import h
 5 | from i import _j
   |
 
 PLC2701 Private name import `_f`
- --> __main__.py:4:18
+ --> __main__.py:4:6
   |
 2 | from _a import b
 3 | from c._d import e
 4 | from _f.g import h
-  |                  ^
+  |      ^^^^
 5 | from i import _j
 6 | from k import _l as m
   |
@@ -45,12 +45,12 @@ PLC2701 Private name import `_j` from external module `i`
   |
 
 PLC2701 Private name import `_l` from external module `k`
- --> __main__.py:6:21
+ --> __main__.py:6:15
   |
 4 | from _f.g import h
 5 | from i import _j
 6 | from k import _l as m
-  |                     ^
+  |               ^^^^^^^
 7 | import _aaa
 8 | import bbb.ccc._ddd as eee  # Panicked in https://github.com/astral-sh/ruff/pull/5920
   |