commands: rename context flag to build-context

Avoid conflicts with docker context

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

build/build.go

@@ -1090,10 +1090,10 @@ func LoadInputs(ctx context.Context, d driver.Driver, inp Inputs, pw progress.Wr
 		}
 		st, err := os.Stat(v)
 		if err != nil {
-			return nil, errors.Wrapf(err, "failed to get context %v", k)
+			return nil, errors.Wrapf(err, "failed to get build context %v", k)
 		}
 		if !st.IsDir() {
-			return nil, errors.Wrapf(syscall.ENOTDIR, "failed to get context path %v", v)
+			return nil, errors.Wrapf(syscall.ENOTDIR, "failed to get build context path %v", v)
 		}
 		localName := k
 		if k == "context" || k == "dockerfile" {

commands/build.go

@@ -347,7 +347,7 @@ func buildCmd(dockerCli command.Cli, rootOpts *rootOptions) *cobra.Command {
 	flags.StringVar(&options.cgroupParent, "cgroup-parent", "", "Optional parent cgroup for the container")
 	flags.SetAnnotation("cgroup-parent", annotation.ExternalURL, []string{"https://docs.docker.com/engine/reference/commandline/build/#use-a-custom-parent-cgroup---cgroup-parent"})
 
-	flags.StringArrayVar(&options.contexts, "context", []string{}, "Additional named contexts (e.g., name=path)")
+	flags.StringArrayVar(&options.contexts, "build-context", []string{}, "Additional build contexts (e.g., name=path)")
 
 	flags.StringVarP(&options.dockerfileName, "file", "f", "", `Name of the Dockerfile (default: "PATH/Dockerfile")`)
 	flags.SetAnnotation("file", annotation.ExternalURL, []string{"https://docs.docker.com/engine/reference/commandline/build/#specify-a-dockerfile--f"})