Lake fails to parse result of config translation script

[Peiran Wu]

Prerequisites

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  • Check that your issue is not already filed.
  • Reduce the issue to a minimal, self-contained, reproducible test case. Avoid dependencies to mathlib4 or std4.

Description

Lake fails to parse the toml configuration file produced by running lake translate-config toml on the default math project template's lakefile.lean.

Context

The toml configuration file is a new feature in v4.8.0-rc1.

Steps to Reproduce

Run the following commands:

lake new example math
cd example
lake translate-config toml
lake build

Expected behavior: Exit without error.

Actual behavior: Error message:

error: lakefile.toml:6:17: expected string, boolean, or nonnegative integer

Versions

Lean (version 4.8.0-rc1, x86_64-unknown-linux-gnu, commit dcccfb7, Release)
Ubuntu 23.10

Additional Information

Content of lakefile.lean prior to translation:

import Lake
open Lake DSL

package «example» where
  -- Settings applied to both builds and interactive editing
  leanOptions := #[
    ⟨`pp.unicode.fun, true⟩, -- pretty-prints `fun a ↦ b`
    ⟨`pp.proofs.withType, false⟩
  ]
  -- add any additional package configuration options here

require mathlib from git
  "https://github.com/leanprover-community/mathlib4.git"

@[default_target]
lean_lib «Example» where
  -- add any library configuration options here

Content of lakefile.toml after translation:

name = "example"

[leanOptions]
pp.unicode.fun = true
pp.proofs.withType = false
defaultTargets = ["Example"]

[[require]]
name = "mathlib"
git = "https://github.com/leanprover-community/mathlib4.git"

[[lean_lib]]
name = "Example"

The aforementioned error does not occur if the line

defaultTargets = ["Example"]

is either moved to line 2 or changed to

defaultTargets = "Example"

Impact

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