Syft fileresolver.containsPath allocates unnecessarily

[yoav-orca]

What happened:
I'm using syft to generate an SBOM for container images, we are seeing OOM conditions due to a lot of heap memory.

All the allocations are coming from this line:
https://github.com/anchore/syft/blob/main/syft/internal/fileresolver/path_skipper.go#L146

Changing it from the original to this:

func containsPath(p1, p2 string) bool {
	p1Clean := simpleClean(p1)
	p2Clean := simpleClean(p2)
	if p1Clean == p2Clean {
		return true
	}
	if !strings.HasPrefix(p1Clean, p2Clean) {
		return false
	}

	// Check if the next character after prefix is '/'
	return len(p1Clean) > len(p2Clean) && p1Clean[len(p2Clean)] == '/'
}

Reduces peak memory.

What you expected to happen:

I expected the compiler to be smart enough not to make a memory allocation at all.

Steps to reproduce the issue:
Use syft.CreateSBOM to generate an SBOM.

Anything else we need to know?:

Environment:

• Output of syft version: I'm using it as a library github.com/anchore/syft v1.18.2-0.20250108175148-b4e7b64d5ce0
• OS (e.g: cat /etc/os-release or similar):

PRETTY_NAME="Debian GNU/Linux 12 (bookworm)"
NAME="Debian GNU/Linux"
VERSION_ID="12"
VERSION="12 (bookworm)"
VERSION_CODENAME=bookworm
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"