Panic in incremental with tsbuildinfo with mismatched `fileNames` and `fileInfos`

[benjaminjkraft]

Stack trace

panic: runtime error: index out of range [61666] with length 61666

goroutine 1 [running]:
github.com/microsoft/typescript-go/internal/incremental.(*toSnapshot).toFilePath(...)
        /Users/benkraft/src/typescript-go/internal/incremental/buildinfotosnapshot.go:61
github.com/microsoft/typescript-go/internal/incremental.(*toSnapshot).setFileInfoAndEmitSignatures(0x140001ac800)
        /Users/benkraft/src/typescript-go/internal/incremental/buildinfotosnapshot.go:104 +0x400
github.com/microsoft/typescript-go/internal/incremental.buildInfoToSnapshot(0x140001c8b40, {0x140011feff0?, 0x46?}, 0x140001c87e0, {0x1031730d8, 0x140001eda40})
        /Users/benkraft/src/typescript-go/internal/incremental/buildinfotosnapshot.go:34 +0x328
github.com/microsoft/typescript-go/internal/incremental.ReadBuildInfoProgram(0x140001c87e0, {0x10316db20, 0x1400021c2c0}, {0x1031730d8, 0x140001eda40})
        /Users/benkraft/src/typescript-go/internal/incremental/incremental.go:53 +0xd4
github.com/microsoft/typescript-go/internal/execute.performIncrementalCompilation({0x103174ed8, 0x14000182c00}, 0x140001c87e0, 0x140011f9140, {0x10316db00, 0x140000c78c0}, 0x5480e30b, {0x0, 0x0})
        /Users/benkraft/src/typescript-go/internal/execute/tsc.go:251 +0x1fc
github.com/microsoft/typescript-go/internal/execute.tscCompilation({0x103174ed8, 0x14000182c00}, 0x140001c8c60, {0x0, 0x0})
        /Users/benkraft/src/typescript-go/internal/execute/tsc.go:198 +0x87c
github.com/microsoft/typescript-go/internal/execute.CommandLine({0x103174ed8, 0x14000182c00}, {0x14000020060, 0x4, 0x4}, {0x0, 0x0})
        /Users/benkraft/src/typescript-go/internal/execute/tsc.go:67 +0x1b4
main.runMain()
        /Users/benkraft/src/typescript-go/cmd/tsgo/main.go:23 +0x120
main.main()
        /Users/benkraft/src/typescript-go/cmd/tsgo/main.go:10 +0x1c

Steps to reproduce

I haven't been able to repro this in isolation -- one of our internal users ran into it and I can repro it by doing an incremental build from their tsbuildinfo file. I don't think I can share the full file but here's a relevant fact about it:

$ jq '.fileInfos|length' path/to/tsconfig.tsbuildinfo
61667
$ jq '.fileNames|length' path/to/tsconfig.tsbuildinfo
61666

Perhaps as a start the tsbuildinfo loader should validate this? It's a bit harder for me to figure out how the tsbuildinfo got that way, but I'm gonna try. (My guess is maybe some kind of casing-conflict or other condition that causes two file-infos for one file name? The code doesn't really look like it ensures they are 1:1, but then it assumes they are, I think.) Let me know if anyone has ideas for what to look at, or which other facts about the tsbuildinfo might be of interest.

[sheetalkamat]

This is duplicate of #1549

We need to come up with a fix in program to not have duplicate files in array - as thats the assumption buildInfo has.