frontend: allow 0 (default) value for healthcheck retries

0 is the default value, so should be ok to explicitly use.

Signed-off-by: Sebastiaan van Stijn <[email protected]>

Author: thaJeztah

frontend/dockerfile/instructions/parse.go

@@ -582,8 +582,8 @@ func parseHealthcheck(req parseRequest) (*HealthCheckCommand, error) {
 			if err != nil {
 				return nil, err
 			}
-			if retries < 1 {
-				return nil, fmt.Errorf("--retries must be at least 1 (not %d)", retries)
+			if retries < 0 {
+				return nil, fmt.Errorf("--retries cannot be negative (%d)", retries)
 			}
 			healthcheck.Retries = int(retries)
 		} else {

frontend/dockerfile/parser/testfiles/health/Dockerfile

@@ -8,3 +8,4 @@ HEALTHCHECK CMD
 HEALTHCHECK   CMD   a b
 HEALTHCHECK --timeout=3s CMD ["foo"]
 HEALTHCHECK CONNECT TCP 7000
+HEALTHCHECK --start-period=0s --interval=5s --timeout=0s --retries=0 CMD ["foo"]

frontend/dockerfile/parser/testfiles/health/result

@@ -7,3 +7,4 @@
 (healthcheck "CMD" "a b")
 (healthcheck ["--timeout=3s"] "CMD" "foo")
 (healthcheck "CONNECT" "TCP 7000")
+(healthcheck ["--start-period=0s" "--interval=5s" "--timeout=0s" "--retries=0"] "CMD" "foo")