TypeError: Class extends value undefined is not a constructor or null

[mwoodpatrick]

When building I'm getting the following error with latest packages and node v16.2.0 (npm v7.13.0)

TypeError: Class extends value undefined is not a constructor or null
at Object.618 (/home/mwoodpatrick/projects/git/www/nextjs-wp/node_modules/next/dist/compiled/postcss-scss/scss-syntax.js:1:100)
at nccwpck_require (/home/mwoodpatrick/projects/git/www/nextjs-wp/node_modules/next/dist/compiled/postcss-scss/scss-syntax.js:1:11843)
at Object.270 (/home/mwoodpatrick/projects/git/www/nextjs-wp/node_modules/next/dist/compiled/postcss-scss/scss-syntax.js:1:413)
at nccwpck_require (/home/mwoodpatrick/projects/git/www/nextjs-wp/node_modules/next/dist/compiled/postcss-scss/scss-syntax.js:1:11843)

at Object.327 (/home/mwoodpatrick/projects/git/www/nextjs-wp/node_modules/next/dist/compiled/postcss-scss/scss-syntax.js:1:260)
at __nccwpck_require__ (/home/mwoodpatrick/projects/git/www/nextjs-wp/node_modules/next/dist/compiled/postcss-scss/scss-syntax.js:1:11843)
at Object.845 (/home/mwoodpatrick/projects/git/www/nextjs-wp/node_modules/next/dist/compiled/postcss-scss/scss-syntax.js:1:3733)
at __nccwpck_require__ (/home/mwoodpatrick/projects/git/www/nextjs-wp/node_modules/next/dist/compiled/postcss-scss/scss-syntax.js:1:11843)
at /home/mwoodpatrick/projects/git/www/nextjs-wp/node_modules/next/dist/compiled/postcss-scss/scss-syntax.js:1:11971
at Object.<anonymous> (/home/mwoodpatrick/projects/git/www/nextjs-wp/node_modules/next/dist/compiled/postcss-scss/scss-syntax.js:1:11997)
at Module._compile (internal/modules/cjs/loader.js:1063:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
at Module.load (internal/modules/cjs/loader.js:928:32)
at Function.Module._load (internal/modules/cjs/loader.js:769:14)
at Module.require (internal/modules/cjs/loader.js:952:19)
at require (internal/modules/cjs/helpers.js:88:18)

[leerob]

Is your code identical to the working examples here?

[mwoodpatrick]

I had added more modules but recreating package-lock.json and node_modules fixed my problem and I was able to deploy to Vercel

[bayram00]

i have a problem like this too

error - Error [TypeError]: Class extends value undefined is not a constructor or null
at ../../node_modules/.pnpm/undici@5.11.0/node_modules/undici/lib/fetch/file.js (evalmachine.:5724:19)
at __require (evalmachine.:14:50)
at ../../node_modules/.pnpm/undici@5.11.0/node_modules/undici/lib/fetch/formdata.js (evalmachine.:5881:49)
at __require (evalmachine.:14:50)
at ../../node_modules/.pnpm/undici@5.11.0/node_modules/undici/lib/fetch/body.js (evalmachine.:6094:35)
at __require (evalmachine.:14:50)
at ../../node_modules/.pnpm/undici@5.11.0/node_modules/undici/lib/fetch/response.js (evalmachine.:6510:49)
at __require (evalmachine.:14:50)
at (evalmachine.:11635:30)
at requireFn (file://C:\Users\Bayram\Desktop\nextapi\node_modules\next\dist\compiled\edge-runtime\index.js:1:7079) {
middleware: true

[fernandolucchesi]

i have a problem like this too

error - Error [TypeError]: Class extends value undefined is not a constructor or null at ../../node_modules/.pnpm/undici@5.11.0/node_modules/undici/lib/fetch/file.js (evalmachine.:5724:19) at __require (evalmachine.:14:50) at ../../node_modules/.pnpm/undici@5.11.0/node_modules/undici/lib/fetch/formdata.js (evalmachine.:5881:49) at __require (evalmachine.:14:50) at ../../node_modules/.pnpm/undici@5.11.0/node_modules/undici/lib/fetch/body.js (evalmachine.:6094:35) at __require (evalmachine.:14:50) at ../../node_modules/.pnpm/undici@5.11.0/node_modules/undici/lib/fetch/response.js (evalmachine.:6510:49) at __require (evalmachine.:14:50) at (evalmachine.:11635:30) at requireFn (file://C:\Users\Bayram\Desktop\nextapi\node_modules\next\dist\compiled\edge-runtime\index.js:1:7079) { middleware: true

same, happening after upgraded to next 13

[fernandolucchesi]

i have a problem like this too

error - Error [TypeError]: Class extends value undefined is not a constructor or null at ../../node_modules/.pnpm/undici@5.11.0/node_modules/undici/lib/fetch/file.js (evalmachine.:5724:19) at __require (evalmachine.:14:50) at ../../node_modules/.pnpm/undici@5.11.0/node_modules/undici/lib/fetch/formdata.js (evalmachine.:5881:49) at __require (evalmachine.:14:50) at ../../node_modules/.pnpm/undici@5.11.0/node_modules/undici/lib/fetch/body.js (evalmachine.:6094:35) at __require (evalmachine.:14:50) at ../../node_modules/.pnpm/undici@5.11.0/node_modules/undici/lib/fetch/response.js (evalmachine.:6510:49) at __require (evalmachine.:14:50) at (evalmachine.:11635:30) at requireFn (file://C:\Users\Bayram\Desktop\nextapi\node_modules\next\dist\compiled\edge-runtime\index.js:1:7079) { middleware: true

Upgrading node fixes this. Check: vercel/next.js#42729

[maniatoffl]

Updating Node version didn't work for me, I had to remove next 13 middleware.ts under src folder, and created custom server.js for handling middlewares. The issue then resolved for me .

[eichgi]

@maniatoffl It seems you need to use node v16.4 at least in order to use a middleware.ts file as I did.

Source: https://stackoverflow.com/questions/74739282/next-js13-middleware-occurs-typeerror-class-extends-value-undefined-is-not-a-c