PostHog CLI glob parser fails on Next.js catch-all routes [[...slug]]

[paulodearaujo]

Bug description

When using @posthog/nextjs-config with sourcemap uploads enabled, the PostHog CLI fails to parse Next.js catch-all route patterns like [[...sign-in]] or [[...slug]].

The CLI's glob parser incorrectly interprets the [...] syntax inside the route name as a character range pattern. For example, [[...sign-in]] is parsed as containing [n-i], which fails because 'n' > 'i' in ASCII order.

Error message:

ERROR posthog_cli::commands: msg="Oops! error parsing glob '**/app/(auth)/sign-in/[[...sign-in]]/page.js': invalid range; 'n' > 'i'"
Oops! error parsing glob '**/app/(auth)/sign-in/[[...sign-in]]/page.js': invalid range; 'n' > 'i'
[PostHog Webpack] Error running PostHog sourcemap plugin: Command failed with code 1

Expected behavior: The CLI should escape or handle Next.js routing conventions ([[...slug]], [...slug], [slug]) which are valid filesystem paths, not glob character ranges.

Actual behavior: The CLI treats square brackets in filenames as glob syntax, causing parsing failures.

How to reproduce

1. Create a Next.js 15 App Router project with Clerk authentication (or any catch-all route)
2. Add a catch-all route like app/(auth)/sign-in/[[...sign-in]]/page.tsx
3. Configure @posthog/nextjs-config with sourcemaps enabled:

   import { withPostHogConfig } from "@posthog/nextjs-config";
   
   export default withPostHogConfig(nextConfig, {
     personalApiKey: process.env.POSTHOG_API_KEY,
     envId: process.env.POSTHOG_ENV_ID,
     sourcemaps: { enabled: true, deleteAfterUpload: true },
   });
   

4. Run next build
5. Observe the glob parsing error

Impact

• The build completes successfully despite the error
• Sourcemaps for routes with catch-all patterns are not uploaded
• Other sourcemaps upload correctly

Environment

• Next.js: 15.5.7
• @posthog/nextjs-config: 1.6.4
• OS: macOS 15.6 (also reproducible on Linux)
• Node: 22.x
• Package manager: pnpm

Suggested fix

The glob library used by posthog-cli should escape square brackets in file paths before constructing glob patterns, or use a literal path matching approach for sourcemap file discovery instead of glob patterns.

Alternatively, paths containing [[ or [... should be treated as literal strings rather than glob syntax.

Related sub-libraries

• [x] @posthog/nextjs-config
• [x] posthog-cli (Rust CLI)

Workaround

Set POSTHOG_SOURCEMAPS=false in environment to disable sourcemap uploads entirely, or accept that catch-all route sourcemaps won't be uploaded.

[marandaneto]

@PostHog/team-error-tracking

[hpouillot]

@paulodearaujo Could you try with the latest nextjs-config version (1.7.1) ? It should have been fixed