update typecheck_only example

examples/typecheck_only/BUILD.bazel

@@ -1,22 +1,19 @@
 """Only type-checks the input file, but does no transpilation or output any typings files.
 
-As such, it cannot run as a Bazel action under `bazel build`, as Bazel will only run actions when
-their outputs are requested.
-
-Therefore this is a test target and should be run with `bazel test`.
+Therefore type-checking is done with a validation action within the `ts_project` rule.
 """
 
-load("@npm//examples:typescript/package_json.bzl", "bin")
+load("@aspect_rules_ts//ts:defs.bzl", "ts_project")
 
-bin.tsc_test(
+ts_project(
     name = "typecheck_only",
-    args = [
-        "--noEmit",
-        "$(location check-me.ts)",
+    srcs = [
+        "check-me.ts",
+        "lib.js",
     ],
-    data = ["check-me.ts"],
-    # It should fail because we made a typing mistake
-    # TypeScript ReturnCode:
-    # OutputGeneratedWithErrors = 2,      // .js and .map generated with semantic errors
-    expected_exit_code = 2,
+    tsconfig = {
+        "compilerOptions": {
+            "noEmit": True,
+        },
+    },
 )

examples/typecheck_only/check-me.ts

@@ -1 +1,2 @@
-const a: number = 'a-string'
+// Ensure importing from .js works
+export * from './lib'

examples/typecheck_only/lib.js

@@ -0,0 +1 @@
+export const a = 42