Use deletion for D215 full-line removals (#7625)

Closes #7619.

crates/ruff_linter/resources/test/fixtures/pydocstyle/D215.py

@@ -0,0 +1,4 @@
+"""
+TODO:
+    -
+"""

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

@@ -79,6 +79,7 @@ mod tests {
     #[test_case(Rule::SectionNameEndsInColon, Path::new("D.py"))]
     #[test_case(Rule::SectionNotOverIndented, Path::new("sections.py"))]
     #[test_case(Rule::SectionNotOverIndented, Path::new("D214_module.py"))]
+    #[test_case(Rule::SectionUnderlineNotOverIndented, Path::new("D215.py"))]
     #[test_case(Rule::SectionUnderlineAfterName, Path::new("sections.py"))]
     #[test_case(Rule::SectionUnderlineMatchesSectionLength, Path::new("sections.py"))]
     #[test_case(Rule::SectionUnderlineNotOverIndented, Path::new("sections.py"))]

crates/ruff_linter/src/rules/pydocstyle/rules/sections.rs

@@ -1440,16 +1440,17 @@ fn blanks_and_section_underline(
                         docstring.range(),
                     );
                     if checker.patch(diagnostic.kind.rule()) {
+                        // Replace the existing indentation with whitespace of the appropriate length.
                         let range = TextRange::at(
                             blank_lines_end,
                             leading_space.text_len() + TextSize::from(1),
                         );
-
-                        // Replace the existing indentation with whitespace of the appropriate length.
-                        diagnostic.set_fix(Fix::automatic(Edit::range_replacement(
-                            clean_space(docstring.indentation),
-                            range,
-                        )));
+                        let contents = clean_space(docstring.indentation);
+                        diagnostic.set_fix(Fix::automatic(if contents.is_empty() {
+                            Edit::range_deletion(range)
+                        } else {
+                            Edit::range_replacement(contents, range)
+                        }));
                     };
                     checker.diagnostics.push(diagnostic);
                 }

crates/ruff_linter/src/rules/pydocstyle/snapshots/ruff_linter__rules__pydocstyle__tests__D215_D215.py.snap

@@ -0,0 +1,21 @@
+---
+source: crates/ruff_linter/src/rules/pydocstyle/mod.rs
+---
+D215.py:1:1: D215 [*] Section underline is over-indented ("TODO")
+  |
+1 | / """
+2 | | TODO:
+3 | |     -
+4 | | """
+  | |___^ D215
+  |
+  = help: Remove over-indentation from "TODO" underline
+
+ℹ Fix
+1 1 | """
+2 2 | TODO:
+3   |-    -
+  3 |+
+4 4 | """
+
+