Fix #76 Raise error if RUN has flags but no arguments

Signed-off-by: Remy Suen <remy.suen@gmail.com>

CHANGELOG.md

@@ -1,6 +1,10 @@
 # Changelog
 All notable changes to this project will be documented in this file.
 
+## [Unreleased]
+### Added
+- RUN instructions with only flags and no arguments will now be raised as an error
+
 ## [0.0.15] - 2020-03-08
 ### Fixed
 - multiline instructions with empty newlines will no longer throw an error during validation ([#71](https://github.com/rcjsuen/dockerfile-utils/issues/71))

package.json

@@ -27,7 +27,7 @@
   "main": "./lib/main.js",
   "types": "./lib/main.d.ts",
   "dependencies": {
-    "dockerfile-ast": "0.0.24",
+    "dockerfile-ast": "0.0.25",
     "vscode-languageserver-types": "3.6.0"
   },
   "devDependencies": {

test/dockerValidator.test.ts

@@ -3813,6 +3813,18 @@ describe("Docker Validator Tests", function() {
             diagnostics = validateDockerfile("FROM busybox\r\nRUN ls && \\\r\n \t# comment");
             assert.equal(diagnostics.length, 0);
         });
+
+        it("flags only with no argument", function () {
+            let diagnostics = validateDockerfile("FROM alpine\nRUN --x=y");
+            assert.equal(diagnostics.length, 1);
+            assertInstructionMissingArgument(diagnostics[0], 1, 0, 1, 3);
+
+            diagnostics = validateDockerfile("FROM alpine\nRUN --x=y --abc=def");
+            assert.equal(diagnostics.length, 1);
+            assertInstructionMissingArgument(diagnostics[0], 1, 0, 1, 3);
+        });
+
+        createSingleQuotedJSONTests("RUN");
     });
 
     describe("SHELL", function() {
@@ -4069,10 +4081,6 @@ describe("Docker Validator Tests", function() {
         });
     });
 
-    describe("RUN", function() {
-        createSingleQuotedJSONTests("RUN");
-    });
-
     describe("USER", function() {
         it("ok", function() {
             return testValidArgument("USER", "daemon");