move integration tests from their own modules into examples (#1513)

The tests are slightly better tests in their own modules, but bazelci
doesn't really have a great way to handle them other than matrix ops on
the working_directory, which causes us to need to generate twice as many
jobs. I need to free up some headroom in order to add bazel 8 tests, so
this is a necessary compromise.

Author: novas0x2a

.bazelci/config.yaml

@@ -27,10 +27,6 @@ matrix:
     Main: ''
     Examples: examples
 
-  mini:
-    Flags: test/standard_cxx_flags_test
-    DetectRoot: test/detect_root_test
-
   exclude:
     # bazel 9 no longer supports workspaces
     - bazel_version: 9.x
@@ -73,17 +69,6 @@ tasks:
 
     test_flags: *primary_flags
 
-  mini:
-    <<: *default_task
-    name: '{mini}/{bazel_version}/{bzlmod}'
-    working_directory: ${{ mini }}
-
-    build_flags: &mini_flags
-      - --config=ci
-      - ${{ bzlmod }}
-
-    test_flags: *mini_flags
-
   docs:
     name: Docs
     platform: ubuntu2404

.bazelignore

@@ -1,4 +1,2 @@
 docs
 examples
-test/standard_cxx_flags_test
-test/detect_root_test

.gitignore

@@ -85,6 +85,4 @@ bazelci.py
 /bazel-*
 /docs/bazel-*
 /examples/bazel-*
-/test/detect_root_test/bazel-*
-/test/standard_cxx_flags_test/bazel-*
 .ijwb/

examples/MODULE.bazel

@@ -27,6 +27,7 @@ bazel_dep(name = "rules_python", version = "1.9.0")
 bazel_dep(name = "rules_cc", version = "0.2.13")
 bazel_dep(name = "rules_shell", version = "0.6.1")
 bazel_dep(name = "rules_perl", version = "1.0.0")
+bazel_dep(name = "with_cfg.bzl", version = "0.14.6")
 
 perl = use_extension("@rules_perl//perl:extensions.bzl", "perl_repositories")
 use_repo(
@@ -139,3 +140,19 @@ use_repo(
 
 bazel_dep(name = "bazel_skylib", version = "1.9.0")
 bazel_dep(name = "bazel_lib", version = "3.2.0")
+
+# Support the integration tests
+
+new_local_repository = use_repo_rule("@bazel_tools//tools/build_defs/repo:local.bzl", "new_local_repository")
+
+new_local_repository(
+    name = "rules_foreign_cc_detect_root_test_repo",
+    build_file_content = """\
+filegroup(
+    name = "srcs",
+    srcs = glob(["**/**"]),
+    visibility = ["//visibility:public"],
+)
+""",
+    path = "integration_tests/detect_root_test/dir1",
+)

examples/MODULE.bazel.lock

@@ -1,6 +1,7 @@
 workspace(name = "rules_foreign_cc_examples")
 
 load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+load("@bazel_tools//tools/build_defs/repo:local.bzl", "new_local_repository")
 
 local_repository(
     name = "rules_foreign_cc",
@@ -15,6 +16,15 @@ load("@bazel_features//:deps.bzl", "bazel_features_deps")
 
 bazel_features_deps()
 
+http_archive(
+    name = "with_cfg.bzl",
+    integrity = "sha256-h4UuEzw3VaVkL+EFQ+4g7acA2uFNMNE9rJbiLqUQbQc=",
+    strip_prefix = "with_cfg.bzl-0.14.6",
+    urls = [
+        "https://github.com/fmeum/with_cfg.bzl/releases/download/v0.14.6/with_cfg.bzl-v0.14.6.tar.gz",
+    ],
+)
+
 load("@rules_cc//cc:extensions.bzl", "compatibility_proxy_repo")
 
 compatibility_proxy_repo()
@@ -190,3 +200,15 @@ load(
 )
 
 rust_example_crate_repositories()
+
+new_local_repository(
+    name = "rules_foreign_cc_detect_root_test_repo",
+    build_file_content = """\
+filegroup(
+    name = "srcs",
+    srcs = glob(["**/**"]),
+    visibility = ["//visibility:public"],
+)
+""",
+    path = "integration_tests/detect_root_test/dir1",
+)

examples/WORKSPACE.bazel

@@ -0,0 +1,8 @@
+# Integration Tests
+
+Integration tests live in the example module instead of the main one because:
+- We want to run them from a seperate module so they're stronger as tests, but...
+- We very rapidly run into max task limits in bazelci if we matrix-generate working_directory tests.
+
+So this is a compromise between testing and CI limits. There are certain types of test that can't be written this way
+(anything testing the extensions...) but that's a problem for another day.