chore: fix basePath redirects for fallback preview mode lol pain

Author: lindsaylevine

Diff for: src/lib/helpers/convertToBasePathRedirects.js

@@ -34,6 +34,13 @@ const convertToBasePathRedirects = ({ basePath, nextRedirects }) => {
         },
       ]
       basePathRedirects.push(...indexRedirects)
+    } else if (r.specialPreviewMode) {
+      basePathRedirects.push({
+        route: `${basePath}${r.route}`,
+        target: r.target,
+        force: true,
+        conditions: r.conditions,
+      })
     } else if (!r.route.includes('_next/') && r.target.includes('/.netlify/functions') && r.conditions) {
       // If this is a preview mode redirect, we need different behavior than other function targets below
       // because the conditions prevent us from doing a route -> basePath/route force

Diff for: src/lib/pages/getStaticPropsWithFallback/redirects.js

@@ -30,6 +30,7 @@ const getRedirects = async () => {
       target: previewModeTarget,
       conditions: PREVIEW_MODE_COOKIES,
       force: true,
+      specialPreviewMode: true,
     })
 
     // Add one redirect pointing to the ODB

Diff for: src/tests/__snapshots__/basePath.test.js.snap

@@ -66,16 +66,12 @@ exports[`Routing creates Netlify redirects 1`] = `
 /foo/getServerSideProps/all/*  /.netlify/functions/next_getServerSideProps_all_slug  200
 /foo/getServerSideProps/:id  /.netlify/functions/next_getServerSideProps_id  200
 /foo/getStaticProps/withFallback/:id  /.netlify/functions/preview-next_getStaticProps_withFallback_id  200!  Cookie=__prerender_bypass,__next_preview_data
-/foo/getStaticProps/withFallback/:id  /getStaticProps/withFallback/[id]  200
 /foo/getStaticProps/withFallback/:id  /.netlify/functions/next_getStaticProps_withFallback_id  200
 /foo/getStaticProps/withFallback/:slug/*  /.netlify/functions/preview-next_getStaticProps_withFallback_slug  200!  Cookie=__prerender_bypass,__next_preview_data
-/foo/getStaticProps/withFallback/:slug/*  /getStaticProps/withFallback/[...slug]  200
 /foo/getStaticProps/withFallback/:slug/*  /.netlify/functions/next_getStaticProps_withFallback_slug  200
 /foo/getStaticProps/withFallbackBlocking/:id  /.netlify/functions/preview-next_getStaticProps_withFallbackBlocking_id  200!  Cookie=__prerender_bypass,__next_preview_data
-/foo/getStaticProps/withFallbackBlocking/:id  /getStaticProps/withFallbackBlocking/[id]  200
 /foo/getStaticProps/withFallbackBlocking/:id  /.netlify/functions/next_getStaticProps_withFallbackBlocking_id  200
 /foo/getStaticProps/withRevalidate/withFallback/:id  /.netlify/functions/preview-next_getStaticProps_withRevalidate_withFallback_id  200!  Cookie=__prerender_bypass,__next_preview_data
-/foo/getStaticProps/withRevalidate/withFallback/:id  /getStaticProps/withRevalidate/withFallback/[id]  200
 /foo/getStaticProps/withRevalidate/withFallback/:id  /.netlify/functions/next_getStaticProps_withRevalidate_withFallback_id  200
 /foo/shows/:id  /.netlify/functions/next_shows_id  200
 /foo/shows/:params/*  /.netlify/functions/next_shows_params  200