html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,issue,performed_via_github_app
https://github.com/simonw/datasette/issues/1650#issuecomment-1060836262,https://api.github.com/repos/simonw/datasette/issues/1650,1060836262,IC_kwDOBm6k_c4_OxOm,9599,2022-03-07T15:52:09Z,2022-03-07T15:52:09Z,OWNER,"This is a bit tricky.

I tried this, sending a redirect only if a 404 happens:

```diff
diff --git a/datasette/app.py b/datasette/app.py
index 8c5480c..420664c 100644
--- a/datasette/app.py
+++ b/datasette/app.py
@@ -1211,6 +1211,10 @@ class DatasetteRouter:
         return await self.handle_404(request, send)
 
     async def handle_404(self, request, send, exception=None):
+        # If path contains % encoding, redirect to dash encoding
+        if '%' in request.scope[""path""]:
+            await asgi_send_redirect(send, request.scope[""path""].replace(""%"", ""-""))
+            return
         # If URL has a trailing slash, redirect to URL without it
         path = request.scope.get(
             ""raw_path"", request.scope[""path""].encode(""utf8"")
```
But this URL didn't work:

- http://127.0.0.1:8001/fivethirtyeight/twitter-ratio%2Fsenators

I was expecting that to redirect to this page:

- http://127.0.0.1:8001/fivethirtyeight/twitter-2Dratio-2Fsenators

But instead it took me to another 404:

- http://127.0.0.1:8001/fivethirtyeight/twitter-ratio%2Fsenators

This is because that URL contains both a %-escaped `/` AND a plain `-` - which was not escaped in the old system but is escaped in the new system.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1160750713,
https://github.com/simonw/datasette/issues/1650#issuecomment-1060863311,https://api.github.com/repos/simonw/datasette/issues/1650,1060863311,IC_kwDOBm6k_c4_O31P,9599,2022-03-07T16:13:17Z,2022-03-07T16:13:17Z,OWNER,"This doesn't seem to work.

https://latest.datasette.io/fixtures/table%2Fwith%2Fslashes.csv should be redirecting now that this is deployed - which it is, because https://latest.datasette.io/-/versions shows 644d25d1de78a36b105cca479e7b3e4375a6eadc - but I'm not getting that redirect.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1160750713,
https://github.com/simonw/datasette/issues/1650#issuecomment-1060864823,https://api.github.com/repos/simonw/datasette/issues/1650,1060864823,IC_kwDOBm6k_c4_O4M3,9599,2022-03-07T16:14:33Z,2022-03-07T16:14:33Z,OWNER,Same problem here: https://fivethirtyeight.datasettes.com/fivethirtyeight/ahca-2Dpolls%2Fahca_polls should redirect but doesn't.,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1160750713,
https://github.com/simonw/datasette/issues/1650#issuecomment-1061038414,https://api.github.com/repos/simonw/datasette/issues/1650,1061038414,IC_kwDOBm6k_c4_PilO,9599,2022-03-07T19:14:04Z,2022-03-07T19:14:04Z,OWNER,"The problem seems to be that `http://127.0.0.1:8002/fixtures/table%2Fwith%2Fslashes.csv` doesn't result in a 404 at all. If it did, it would be redirected.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1160750713,
https://github.com/simonw/datasette/issues/1650#issuecomment-1061041034,https://api.github.com/repos/simonw/datasette/issues/1650,1061041034,IC_kwDOBm6k_c4_PjOK,9599,2022-03-07T19:16:51Z,2022-03-07T19:16:51Z,OWNER,"Here's the problem: https://github.com/simonw/datasette/blob/020effe47bf89f35182960a9645f2383a42ebd54/datasette/utils/__init__.py#L1173-L1175

Which is called here:

https://github.com/simonw/datasette/blob/1baa030eca375f839f3471237547ab403523e643/datasette/views/base.py#L469-L473

So `table%2Fwith%2Fslashes` ends up decoded as if it was  using dash encoding.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1160750713,