Merge pull request #2932 from umohnani8/1.19

[release-1.19] Use build-arg ENV val from local environment if set

cmd/buildah/bud.go

@@ -129,7 +129,12 @@ func budCmd(c *cobra.Command, inputArgs []string, iopts budOptions) error {
 			if len(av) > 1 {
 				args[av[0]] = av[1]
 			} else {
-				delete(args, av[0])
+				// check if the env is set in the local environment and use that value if it is
+				if val, present := os.LookupEnv(av[0]); present {
+					args[av[0]] = val
+				} else {
+					delete(args, av[0])
+				}
 			}
 		}
 	}

tests/bud.bats

@@ -2154,9 +2154,15 @@ EOM
 }
 
 @test "bud with --build-arg" {
-  _prefetch alpine
-  run_buildah --log-level "warn" bud --signature-policy ${TESTSDIR}/policy.json -t test ${TESTSDIR}/bud/build-arg
+  _prefetch alpine busybox
+  target=busybox-image
+  run_buildah --log-level "warn" bud --signature-policy ${TESTSDIR}/policy.json -t ${target} ${TESTSDIR}/bud/build-arg
   expect_output --substring 'missing .+ build argument'
+  run_buildah bud --signature-policy ${TESTSDIR}/policy.json -t ${target} --build-arg foo=bar ${TESTSDIR}/bud/build-arg
+  expect_output --substring "bar"
+  export foo=hello-world
+  run_buildah bud --signature-policy ${TESTSDIR}/policy.json -t ${target} --build-arg foo ${TESTSDIR}/bud/build-arg
+  expect_output --substring "hello-world"
 }
 
 @test "bud arg and env var with same name" {

tests/bud/build-arg/Dockerfile

@@ -1,3 +1,3 @@
 FROM busybox
-
 ARG foo
+RUN echo $foo