Multiple file output does not work with symlinks

[pauloborges]

Using a regular output directory:

$ pkl eval -m output birds.pkl
output/birds/pigeon.json
output/birds/parrot.yaml
$ pkl eval -m output birds.pkl
output/birds/pigeon.json
output/birds/parrot.yaml

birds.pkl has the same content as the example in the documentation.

Using a symlink:

$ DIR=$(mktemp -d)
$ pkl eval -m $DIR birds.pkl
../../../../../var/folders/p2/m6p8_spd68j2jbdnzwxxrvgr0000gn/T/tmp.ZMUU0W8BMv/birds/pigeon.json
../../../../../var/folders/p2/m6p8_spd68j2jbdnzwxxrvgr0000gn/T/tmp.ZMUU0W8BMv/birds/parrot.yaml
$ pkl eval -m $DIR birds.pkl
Output file conflict: `output.files` entry `"birds/pigeon.json"` in module `file:///[redacted]/birds.pkl` resolves to file path `/private/var/folders/p2/m6p8_spd68j2jbdnzwxxrvgr0000gn/T/tmp.ZMUU0W8BMv/birds/pigeon.json`, which is outside output directory `/var/folders/p2/m6p8_spd68j2jbdnzwxxrvgr0000gn/T/tmp.ZMUU0W8BMv`.

macOS symlinks /var to /private/var.

The related code path is the following:

pkl/pkl-cli/src/main/kotlin/org/pkl/cli/CliEvaluator.kt

Lines 221 to 227 in 8e15556

	val resolvedPath = outputDir.resolve(pathSpec).normalize()
	val realPath = if (resolvedPath.exists()) resolvedPath.toRealPath() else resolvedPath
	if (!realPath.startsWith(outputDir)) {
	throw CliException(
	"Output file conflict: `output.files` entry `\"$pathSpec\"` in module `$moduleUri` resolves to file path `$realPath`, which is outside output directory `$outputDir`."
	)
	}