Add support for the SHELL Dockerfile command

.dockerfilelintrc

@@ -0,0 +1,2 @@
+rules:
+  uppercase_commands: off

lib/checks.js

@@ -152,5 +152,14 @@ var commands = module.exports = {
 
       return result;
     }
+  },
+
+  is_valid_shell: function(args) {
+    // Dockerfile syntax requires that args be in JSON array format
+    var parsed = JSON.parse(args);
+    if (parsed.constructor !== Array) {
+      return ['invalid_format'];
+    }
+    return [];
   }
 }

lib/index.js

@@ -257,6 +257,11 @@ function runLine(state, instructions, idx) {
         break;
       case 'stopsignal':
         break;
+      case 'shell':
+        checks.is_valid_shell(args).forEach(function(item) {
+          items.push(messages.build(state.rules, item, line));
+        });
+        break;
       default:
          items.push(messages.build(state.rules, 'invalid_command', line));
          break;

test/cli_reporter.js

@@ -98,7 +98,7 @@ describe('cli_reporter', () => {
       expect(Object.keys(reporter.fileReports)).to.have.length(1);
       let fileReport = reporter.fileReports[file];
       expect(fileReport.uniqueIssues).to.equal(3);
-      expect(fileReport.contentArray).to.have.length(34);
+      expect(fileReport.contentArray).to.have.length(35);
       expect(fileReport.itemsByLine).to.deep.equal({
         '5': [ items[0] ],
         '6': items.splice(1)
@@ -126,7 +126,7 @@ describe('cli_reporter', () => {
       expect(Object.keys(reporter.fileReports)).to.have.length(1);
       let fileReport = reporter.fileReports[file];
       expect(fileReport.uniqueIssues).to.equal(1);
-      expect(fileReport.contentArray).to.have.length(34);
+      expect(fileReport.contentArray).to.have.length(35);
       expect(fileReport.itemsByLine).to.deep.equal({
         '6': [ items[0] ]
       });
@@ -171,7 +171,7 @@ describe('cli_reporter', () => {
       });
       let file2Report = reporter.fileReports[file2];
       expect(file2Report.uniqueIssues).to.equal(2);
-      expect(file2Report.contentArray).to.have.length(34);
+      expect(file2Report.contentArray).to.have.length(35);
       expect(file2Report.itemsByLine).to.deep.equal({
         '5': [ file2Items[0] ],
         '6': [ file2Items[1] ]

test/examples/Dockerfile.misc

@@ -30,4 +30,5 @@ ONBUILD RUN echo test
 STOPSIGNAL SIGKILL
 ADD /test* /test2
 CMD ["bash"]
+SHELL ["/bin/sh", "-c"]
 ENTRYPOINT ["bash"]

test/examples/Dockerfile.shell.fail

@@ -0,0 +1,5 @@
+FROM alpine:4
+
+SHELL ["/bin/sh"]
+SHELL "bin/sh"
+SHELL ["/bin/sh", "-c"]

test/examples/Dockerfile.shell.pass

@@ -0,0 +1,3 @@
+FROM alpine:4
+
+SHELL ["/bin/sh", "-c"]

test/index.js

@@ -64,6 +64,27 @@ describe("index", function(){
     });
   });
 
+  describe("#shell", function() {
+    it("validates the shell command is accepted when entered correctly", function() {
+      expect(dockerfilelint.run('./test/examples', fs.readFileSync('./test/examples/Dockerfile.shell.pass', 'UTF-8'))).to.be.empty;
+    });
+
+    it("validates the shell command detects invalid shell commands", function() {
+      var expected = [
+        { title: 'Invalid Argument Format',
+          line: 4,
+          rule: 'invalid_format'}
+      ];
+      var result = dockerfilelint.run('./test/examples', fs.readFileSync('./test/examples/Dockerfile.shell.fail', 'UTF-8'));
+      _.forEach(result, function(r) {
+        delete r['description'];
+        delete r['category'];
+      });
+      expect(result).to.have.length(expected.length);
+      expect(result).to.deep.equal(expected);
+    });
+  });
+
   describe("#misc", function(){
     it("validates the misc Dockerfile have the exact right issues reported", function(){
       var expected = [