S2 EsLint implementation

ci/CiTests.java

@@ -102,6 +102,21 @@ class CiTests {
                 equal(0L,f.calls("build")); equal(0L,f.calls("push"));
             }
         });
+        test("Frontend lint runs after install and blocks tests and build on failure", () -> {
+            try (Fixture f = new Fixture()) {
+                f.fake.lintFailure = true;
+                try { f.pipeline.verifyFrontend(); throw new AssertionError("Expected failure"); }
+                catch (Commands.Failure error) { equal(1,error.exitCode); }
+                equal(List.of(List.of("npm", "ci"), List.of("npm", "run", "lint")), f.fake.calls);
+            }
+        });
+        test("Frontend verification checks before testing and building", () -> {
+            try (Fixture f = new Fixture()) {
+                f.pipeline.verifyFrontend();
+                equal(List.of("ci", "run lint", "test -- --reporters=default --reporters=junit --output-file=unit-results/junit.xml", "run build"),
+                        f.fake.calls.stream().map(a -> String.join(" ", a.subList(1,a.size()))).toList());
+            }
+        });
         test("Process execution enforces its deadline", () -> {
             Path dir = Files.createTempDirectory("ci-process-test-");
             try {
@@ -135,13 +150,14 @@ class CiTests {
         final List<List<String>> calls = new ArrayList<>();
         final Map<String,String> images = new HashMap<>(), tags = new HashMap<>();
         String head = SHA, pushFailure = "", pullFailure = "";
-        boolean manifestError, mavenFailure;
+        boolean manifestError, mavenFailure, lintFailure;
         boolean dockerAvailable = true;
         FakeCommands() { super(Duration.ofMinutes(1)); }
         @Override Result execute(List<String> args, Path cwd, Map<String,String> env, String input, boolean echo) {
             calls.add(List.copyOf(args));
             if (args.getFirst().equals("git")) return new Result(0,SHA);
             if (args.getFirst().equals("mvn") && mavenFailure) return new Result(42,"deliberate failure");
+            if (args.equals(List.of("npm", "run", "lint")) && lintFailure) return new Result(1,"deliberate lint failure");
             if (!args.getFirst().equals("docker")) return new Result(0,"");
             String command = args.get(1), ref = args.getLast();
             if (command.equals("info")) return new Result(dockerAvailable ? 0 : 1,args.contains("{{.Architecture}}") ? "amd64" : "linux");