Dockerfiles with quotes on base image tags fail to parse

[nkubala]

Expected behavior

Dockerfile parses correctly and skaffold build builds container image

Actual behavior

skaffold build fails with:

➜  getting-started git:(main) ✗ skaffold build 
Generating tags...
 - skaffold-example -> skaffold-example:v1.35.0-54-ga04528748-dirty
Checking cache...
 - skaffold-example: Error checking cache.
getting hash for artifact "skaffold-example": getting dependencies for "skaffold-example": parsing ONBUILD instructions: retrieving image "golang:\"1.15": parsing reference "golang:\"1.15": could not parse reference: golang:"1.15

Information

• Skaffold version: v1.35.2 (or any)
• Contents of skaffold.yaml:

<paste your skaffold.yaml here>

Dockerfile:

FROM golang:"1.15"
RUN ls

This is happening because in our parsing logic, we remove quotes around base images provided in the FROM clause, but we only removing leading/trailing. This results in golang:"1.15" being passed in as golang:"1.15, which fails.

skaffold/pkg/skaffold/docker/parse.go

Lines 443 to 451 in a045287

	func unquote(v string) string {
	unquoted := strings.TrimFunc(v, func(r rune) bool { return r == '"' })
	if unquoted != v {
	return unquoted
	}
	unquoted = strings.TrimFunc(v, func(r rune) bool { return r == '\'' })
	return unquoted
	}