add autofix

crates/ruff_linter/src/rules/flake8_django/rules/url_path_without_trailing_slash.rs

@@ -1,10 +1,10 @@
 use ruff_macros::{ViolationMetadata, derive_message_formats};
 use ruff_python_ast::{self as ast, Expr};
 use ruff_python_semantic::Modules;
-use ruff_text_size::Ranged;
+use ruff_text_size::{Ranged, TextSize};
 
-use crate::Violation;
 use crate::checkers::ast::Checker;
+use crate::{AlwaysFixableViolation, Edit, Fix};
 
 /// ## What it does
 /// Checks that all Django URL route definitions using `django.urls.path()`
@@ -47,12 +47,16 @@ pub(crate) struct DjangoURLPathWithoutTrailingSlash {
     url_pattern: String,
 }
 
-impl Violation for DjangoURLPathWithoutTrailingSlash {
+impl AlwaysFixableViolation for DjangoURLPathWithoutTrailingSlash {
     #[derive_message_formats]
     fn message(&self) -> String {
         let DjangoURLPathWithoutTrailingSlash { url_pattern } = self;
         format!("URL route `{url_pattern}` is missing a trailing slash")
     }
+
+    fn fix_title(&self) -> String {
+        "Add trailing slash".to_string()
+    }
 }
 
 /// DJ014
@@ -94,11 +98,35 @@ pub(crate) fn url_path_without_trailing_slash(checker: &Checker, call: &ast::Exp
         }
 
         // Report diagnostic for routes without trailing slash
-        checker.report_diagnostic(
+        let mut diagnostic = checker.report_diagnostic(
             DjangoURLPathWithoutTrailingSlash {
                 url_pattern: route.to_string(),
             },
             route_arg.range(),
         );
+
+        // Generate fix: add trailing slash to the string content
+        // We need to find the position of the closing quote and insert "/" before it
+        let string_range = route_arg.range();
+        let locator = checker.locator();
+        let string_content = locator.slice(string_range);
+
+        // Find the closing quote(s) by working backwards from the end
+        // Handle both single quotes, double quotes, and their triple variants
+        let quote_len = if string_content.ends_with("'''") || string_content.ends_with("\"\"\"") {
+            3
+        } else if string_content.ends_with('\'') || string_content.ends_with('"') {
+            1
+        } else {
+            // Shouldn't happen for a valid string literal
+            return;
+        };
+
+        // Insert "/" before the closing quote(s)
+        let insertion_point = string_range.end() - TextSize::new(quote_len);
+        diagnostic.set_fix(Fix::safe_edit(Edit::insertion(
+            "/".to_string(),
+            insertion_point,
+        )));
     }
 }

crates/ruff_linter/src/rules/flake8_django/snapshots/ruff_linter__rules__flake8_django__tests__DJ014_DJ014.py.snap

@@ -1,7 +1,7 @@
 ---
 source: crates/ruff_linter/src/rules/flake8_django/mod.rs
 ---
-DJ014 URL route `help` is missing a trailing slash
+DJ014 [*] URL route `help` is missing a trailing slash
  --> DJ014.py:6:10
   |
 4 | # Errors - missing trailing slash
@@ -11,8 +11,17 @@ DJ014 URL route `help` is missing a trailing slash
 7 |     path("about", views.about_view),  # DJ014
 8 |     path("contact", views.contact_view),  # DJ014
   |
+help: Add trailing slash
+3 | 
+4 | # Errors - missing trailing slash
+5 | urlpatterns = [
+  -     path("help", views.help_view),  # DJ014
+6 +     path("help/", views.help_view),  # DJ014
+7 |     path("about", views.about_view),  # DJ014
+8 |     path("contact", views.contact_view),  # DJ014
+9 |     path("api/users", views.users_view),  # DJ014
 
-DJ014 URL route `about` is missing a trailing slash
+DJ014 [*] URL route `about` is missing a trailing slash
  --> DJ014.py:7:10
   |
 5 | urlpatterns = [
@@ -22,8 +31,17 @@ DJ014 URL route `about` is missing a trailing slash
 8 |     path("contact", views.contact_view),  # DJ014
 9 |     path("api/users", views.users_view),  # DJ014
   |
+help: Add trailing slash
+4  | # Errors - missing trailing slash
+5  | urlpatterns = [
+6  |     path("help", views.help_view),  # DJ014
+   -     path("about", views.about_view),  # DJ014
+7  +     path("about/", views.about_view),  # DJ014
+8  |     path("contact", views.contact_view),  # DJ014
+9  |     path("api/users", views.users_view),  # DJ014
+10 |     path("blog/posts", views.posts_view),  # DJ014
 
-DJ014 URL route `contact` is missing a trailing slash
+DJ014 [*] URL route `contact` is missing a trailing slash
   --> DJ014.py:8:10
    |
  6 |     path("help", views.help_view),  # DJ014
@@ -33,8 +51,17 @@ DJ014 URL route `contact` is missing a trailing slash
  9 |     path("api/users", views.users_view),  # DJ014
 10 |     path("blog/posts", views.posts_view),  # DJ014
    |
+help: Add trailing slash
+5  | urlpatterns = [
+6  |     path("help", views.help_view),  # DJ014
+7  |     path("about", views.about_view),  # DJ014
+   -     path("contact", views.contact_view),  # DJ014
+8  +     path("contact/", views.contact_view),  # DJ014
+9  |     path("api/users", views.users_view),  # DJ014
+10 |     path("blog/posts", views.posts_view),  # DJ014
+11 | ]
 
-DJ014 URL route `api/users` is missing a trailing slash
+DJ014 [*] URL route `api/users` is missing a trailing slash
   --> DJ014.py:9:10
    |
  7 |     path("about", views.about_view),  # DJ014
@@ -44,8 +71,17 @@ DJ014 URL route `api/users` is missing a trailing slash
 10 |     path("blog/posts", views.posts_view),  # DJ014
 11 | ]
    |
+help: Add trailing slash
+6  |     path("help", views.help_view),  # DJ014
+7  |     path("about", views.about_view),  # DJ014
+8  |     path("contact", views.contact_view),  # DJ014
+   -     path("api/users", views.users_view),  # DJ014
+9  +     path("api/users/", views.users_view),  # DJ014
+10 |     path("blog/posts", views.posts_view),  # DJ014
+11 | ]
+12 | 
 
-DJ014 URL route `blog/posts` is missing a trailing slash
+DJ014 [*] URL route `blog/posts` is missing a trailing slash
   --> DJ014.py:10:10
    |
  8 |     path("contact", views.contact_view),  # DJ014
@@ -54,8 +90,17 @@ DJ014 URL route `blog/posts` is missing a trailing slash
    |          ^^^^^^^^^^^^
 11 | ]
    |
+help: Add trailing slash
+7  |     path("about", views.about_view),  # DJ014
+8  |     path("contact", views.contact_view),  # DJ014
+9  |     path("api/users", views.users_view),  # DJ014
+   -     path("blog/posts", views.posts_view),  # DJ014
+10 +     path("blog/posts/", views.posts_view),  # DJ014
+11 | ]
+12 | 
+13 | # OK - has trailing slash
 
-DJ014 URL route `bad` is missing a trailing slash
+DJ014 [*] URL route `bad` is missing a trailing slash
   --> DJ014.py:37:10
    |
 35 | urlpatterns_mixed = [
@@ -65,8 +110,17 @@ DJ014 URL route `bad` is missing a trailing slash
 38 |     path("also-good/", views.also_good_view),
 39 |     path("also-bad", views.also_bad_view),  # DJ014
    |
+help: Add trailing slash
+34 | # Mixed cases
+35 | urlpatterns_mixed = [
+36 |     path("good/", views.good_view),
+   -     path("bad", views.bad_view),  # DJ014
+37 +     path("bad/", views.bad_view),  # DJ014
+38 |     path("also-good/", views.also_good_view),
+39 |     path("also-bad", views.also_bad_view),  # DJ014
+40 | ]
 
-DJ014 URL route `also-bad` is missing a trailing slash
+DJ014 [*] URL route `also-bad` is missing a trailing slash
   --> DJ014.py:39:10
    |
 37 |     path("bad", views.bad_view),  # DJ014
@@ -75,3 +129,10 @@ DJ014 URL route `also-bad` is missing a trailing slash
    |          ^^^^^^^^^^
 40 | ]
    |
+help: Add trailing slash
+36 |     path("good/", views.good_view),
+37 |     path("bad", views.bad_view),  # DJ014
+38 |     path("also-good/", views.also_good_view),
+   -     path("also-bad", views.also_bad_view),  # DJ014
+39 +     path("also-bad/", views.also_bad_view),  # DJ014
+40 | ]