Expose redirect path in RequestRedirect

When we raise the RequestRedirect exception
we have already computed the new url that
should be redirected to in the exception
(new_url) but we don't pass the the
new path that we used to compute the url.

This causes another layer of redirection
in depending code that needs to urlparse()
the url to get the path we already have
the data for.

This adds new_path to the RequestRedirect
exception and populates it with the path
used when computing new_url.

Fixes: pallets#3000

src/werkzeug/routing/exceptions.py

@@ -34,9 +34,10 @@ class RequestRedirect(HTTPException, RoutingException):
 
     code = 308
 
-    def __init__(self, new_url: str) -> None:
+    def __init__(self, new_url: str, new_path: t.Optional[str] = None) -> None:
         super().__init__(new_url)
         self.new_url = new_url
+        self.new_path = new_path
 
     def get_response(
         self,
@@ -98,7 +99,8 @@ def _score_rule(rule: Rule) -> float:
                         str(rule.endpoint),
                         str(self.endpoint),
                     ).ratio(),
-                    0.01 * bool(set(self.values or ()).issubset(rule.arguments)),
+                    0.01 * bool(set(self.values or ()
+                                    ).issubset(rule.arguments)),
                     0.01 * bool(rule.methods and self.method in rule.methods),
                 ]
             )
@@ -134,7 +136,8 @@ def __str__(self) -> str:
                         f" Did you forget to specify values {sorted(missing_values)!r}?"
                     )
             else:
-                message.append(f" Did you mean {self.suggested.endpoint!r} instead?")
+                message.append(
+                    f" Did you mean {self.suggested.endpoint!r} instead?")
         return "".join(message)
 
 

src/werkzeug/routing/map.py

@@ -222,7 +222,8 @@ def bind(
         server_name = server_name.lower()
         if self.host_matching:
             if subdomain is not None:
-                raise RuntimeError("host matching enabled and a subdomain was provided")
+                raise RuntimeError(
+                    "host matching enabled and a subdomain was provided")
         elif subdomain is None:
             subdomain = self.default_subdomain
         if script_name is None:
@@ -602,12 +603,14 @@ def match(
         path_part = f"/{path_info.lstrip('/')}" if path_info else ""
 
         try:
-            result = self.map._matcher.match(domain_part, path_part, method, websocket)
+            result = self.map._matcher.match(
+                domain_part, path_part, method, websocket)
         except RequestPath as e:
             # safe = https://url.spec.whatwg.org/#url-path-segment-string
             new_path = quote(e.path_info, safe="!$&'()*+,/:;=@")
             raise RequestRedirect(
-                self.make_redirect_url(new_path, query_args)
+                self.make_redirect_url(new_path, query_args),
+                new_path,
             ) from None
         except RequestAliasRedirect as e:
             raise RequestRedirect(
@@ -617,11 +620,13 @@ def match(
                     e.matched_values,
                     method,
                     query_args,
-                )
+                ),
+                path_part,
             ) from None
         except NoMatch as e:
             if e.have_match_for:
-                raise MethodNotAllowed(valid_methods=list(e.have_match_for)) from None
+                raise MethodNotAllowed(
+                    valid_methods=list(e.have_match_for)) from None
 
             if e.websocket_mismatch:
                 raise WebsocketMismatch() from None
@@ -631,9 +636,10 @@ def match(
             rule, rv = result
 
             if self.map.redirect_defaults:
-                redirect_url = self.get_default_redirect(rule, method, rv, query_args)
+                (redirect_url, redirect_path) = self.get_default_redirect(
+                    rule, method, rv, query_args)
                 if redirect_url is not None:
-                    raise RequestRedirect(redirect_url)
+                    raise RequestRedirect(redirect_url, redirect_path)
 
             if rule.redirect_to is not None:
                 if isinstance(rule.redirect_to, str):
@@ -642,7 +648,8 @@ def _handle_match(match: t.Match[str]) -> str:
                         value = rv[match.group(1)]
                         return rule._converters[match.group(1)].to_url(value)
 
-                    redirect_url = _simple_rule_re.sub(_handle_match, rule.redirect_to)
+                    redirect_url = _simple_rule_re.sub(
+                        _handle_match, rule.redirect_to)
                 else:
                     redirect_url = rule.redirect_to(self, **rv)
 
@@ -655,7 +662,8 @@ def _handle_match(match: t.Match[str]) -> str:
                     urljoin(
                         f"{self.url_scheme or 'http'}://{netloc}{self.script_name}",
                         redirect_url,
-                    )
+                    ),
+                    redirect_url,
                 )
 
             if return_rule:
@@ -736,8 +744,9 @@ def get_default_redirect(
             if r.provides_defaults_for(rule) and r.suitable_for(values, method):
                 values.update(r.defaults)  # type: ignore
                 domain_part, path = r.build(values)  # type: ignore
-                return self.make_redirect_url(path, query_args, domain_part=domain_part)
-        return None
+                return self.make_redirect_url(path, query_args,
+                                              domain_part=domain_part), path
+        return None, None
 
     def encode_query_args(self, query_args: t.Mapping[str, t.Any] | str) -> str:
         if not isinstance(query_args, str):