Accept a Locator for ast::whitespace::indentation

Co-authored-by: Charlie Marsh <charlie.r.marsh@gmail.com>
Signed-off-by: Anders Kaseorg <andersk@mit.edu>

src/ast/whitespace.rs

@@ -4,12 +4,12 @@ use std::str::Lines;
 use rustpython_ast::{Located, Location};
 
 use crate::ast::types::Range;
-use crate::checkers::ast::Checker;
+use crate::source_code::Locator;
 
 /// Extract the leading indentation from a line.
-pub fn indentation<'a, T>(checker: &'a Checker, located: &'a Located<T>) -> Cow<'a, str> {
+pub fn indentation<'a, T>(locator: &'a Locator, located: &'a Located<T>) -> Cow<'a, str> {
     let range = Range::from_located(located);
-    checker.locator.slice_source_code_range(&Range::new(
+    locator.slice_source_code_range(&Range::new(
         Location::new(range.location.row(), 0),
         Location::new(range.location.row(), range.location.column()),
     ))

src/rules/flake8_return/rules.rs

@@ -108,7 +108,7 @@ fn implicit_return(checker: &mut Checker, last_stmt: &Stmt) {
                 Diagnostic::new(violations::ImplicitReturn, Range::from_located(last_stmt));
             if checker.patch(&RuleCode::RET503) {
                 let mut content = String::new();
-                content.push_str(&indentation(checker, last_stmt));
+                content.push_str(&indentation(&checker.locator, last_stmt));
                 content.push_str("return None");
                 content.push('\n');
                 diagnostic.amend(Fix::insertion(

src/rules/pyupgrade/rules/replace_stdout_stderr.rs

@@ -89,7 +89,7 @@ pub fn replace_stdout_stderr(checker: &mut Checker, expr: &Expr, kwargs: &[Keywo
                 if middle.multi_line {
                     contents.push(',');
                     contents.push('\n');
-                    contents.push_str(&indentation(checker, first));
+                    contents.push_str(&indentation(&checker.locator, first));
                 } else {
                     contents.push(',');
                     contents.push(' ');

src/rules/pyupgrade/rules/rewrite_mock_import.rs

@@ -227,7 +227,7 @@ pub fn rewrite_mock_import(checker: &mut Checker, stmt: &Stmt) {
             {
                 // Generate the fix, if needed, which is shared between all `mock` imports.
                 let content = if checker.patch(&RuleCode::UP026) {
-                    let indent = indentation(checker, stmt);
+                    let indent = indentation(&checker.locator, stmt);
                     match format_import(stmt, &indent, checker.locator, checker.stylist) {
                         Ok(content) => Some(content),
                         Err(e) => {
@@ -273,7 +273,7 @@ pub fn rewrite_mock_import(checker: &mut Checker, stmt: &Stmt) {
                     Range::from_located(stmt),
                 );
                 if checker.patch(&RuleCode::UP026) {
-                    let indent = indentation(checker, stmt);
+                    let indent = indentation(&checker.locator, stmt);
                     match format_import_from(stmt, &indent, checker.locator, checker.stylist) {
                         Ok(content) => {
                             diagnostic.amend(Fix::replacement(