build: add bazel-jest rule that works with tests that do not require …

…TestBed (#2533)

BUILD.bazel

@@ -4,4 +4,8 @@ package(default_visibility = ["//visibility:public"])
 exports_files([
     "tsconfig.json",
     "LICENSE",
+    # used by ts_jest_test
+    "jest.config.js",
+    "setup-jest.ts",
+    "tsconfig.json",
 ])

modules/component-store/spec/BUILD

@@ -1,7 +1,7 @@
-load("//tools:defaults.bzl", "jasmine_node_test", "ts_test_library")
+load("//tools:defaults.bzl", "ts_jest_test")
 
-ts_test_library(
-    name = "test_lib",
+ts_jest_test(
+    name = "test",
     srcs = glob(
         [
             "**/*.ts",
@@ -12,10 +12,3 @@ ts_test_library(
         "@npm//rxjs",
     ],
 )
-
-jasmine_node_test(
-    name = "test",
-    deps = [
-        ":test_lib",
-    ],
-)

tools/defaults.bzl

@@ -1,6 +1,7 @@
 """Re-export of some bazel rules with repository-wide defaults."""
 
 load("@build_bazel_rules_nodejs//:index.bzl", _pkg_npm = "pkg_npm")
+load("@npm//jest-cli:index.bzl", _jest_test = "jest_test")
 load("@npm_angular_bazel//:index.bzl", _ng_module = "ng_module", _ng_package = "ng_package")
 load("@npm_bazel_jasmine//:index.bzl", _jasmine_node_test = "jasmine_node_test")
 load("@npm_bazel_typescript//:index.bzl", _ts_library = "ts_library")
@@ -108,6 +109,35 @@ def jasmine_node_test(node_modules = None, deps = [], **kwargs):
         **kwargs
     )
 
+def ts_jest_test(name, srcs, deps = [], **kwargs):
+    # A macro around the autogenerated jest_test rule.
+    # Takes TS files as srcs and runs jest with them. Jest uses TS compiler
+    # to transform the sources into JS.
+    args = [
+        "--no-cache",
+        "--no-watchman",
+        "--ci",
+    ]
+
+    jest_config = "//:jest.config.js"
+    args.extend(["--config", "$(location %s)" % jest_config])
+
+    for src in srcs:
+        args.extend(["--runTestsByPath", "$(locations %s)" % src])
+
+    _jest_test(
+        name = name,
+        data = [
+            "@npm//typescript",
+            "@npm//jest-preset-angular",
+            "//:setup-jest.ts",
+            "//:tsconfig.json",
+            jest_config,
+        ] + deps + srcs,
+        args = args,
+        **kwargs
+    )
+
 def ng_module(name, tsconfig = None, entry_point = None, deps = [], **kwargs):
     if not tsconfig:
         tsconfig = DEFAULT_TSCONFIG