Implement small world integration test project (#177)

Implement a small world project, which shows (and tests) the basic use
of some `rules_swiftnav` repos and tests the coverage with the clang
toolchains.
It contains some basic libs, which follow the old/legacy "cmake" folder
structure and the modern Bazel folder structure.

Author: martin4861

.bazeliskrc

@@ -1 +1 @@
-USE_BAZEL_VERSION=7.6.1
+USE_BAZEL_VERSION=8.3.1

.github/workflows/ci.yaml

@@ -7,26 +7,45 @@ on:
       - 'main'
 
 jobs:
-
   check-formatting:
     runs-on: ubuntu-latest
     steps:
-      - name: Set up credentials
-        uses: aws-actions/configure-aws-credentials@v1
+      - name: Checkout source
+        uses: actions/checkout@v5
+
+      - uses: bazel-contrib/[email protected]
+
+      - name: Mount bazel cache
+        uses: actions/cache@v4
         with:
-          aws-access-key-id: ${{ secrets.AWS_ACCESS_KEY_ID }}
-          aws-secret-access-key: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
-          aws-region: us-west-2
+          path: "~/.cache/bazel"
+          key: bazel
 
-      - name: Set up cache
+      - name: Run format
         run: |
-          npm install -g bazels3cache
-          bazels3cache --bucket=${{ secrets.BAZEL_BUCKET }}
+          bazel run //:buildifier
+          git diff --exit-code
 
+  example-small-world:
+    runs-on: ubuntu-latest
+    steps:
       - name: Checkout source
-        uses: actions/checkout@v2
+        uses: actions/checkout@v5
+
+      - uses: bazel-contrib/[email protected]
+
+      - name: Mount bazel cache
+        uses: actions/cache@v4
+        with:
+          path: "~/.cache/bazel"
+          key: bazel-example-small-world
+
+      - name: Build and generate coverage
+        run: |
+          cd examples/small_world
+          ./scripts/generate_coverage.sh
 
       - name: Run format
         run: |
-          bazel run --remote_cache=http://localhost:7777 //:buildifier
+          bazel run //:buildifier
           git diff --exit-code

.gitignore

@@ -1 +1 @@
-/bazel-*
+bazel-*

MODULE.bazel

@@ -15,10 +15,10 @@ module(
 )
 
 # Core Bazel dependencies
-bazel_dep(name = "bazel_skylib", version = "1.4.1")
-bazel_dep(name = "platforms", version = "0.0.6")
-bazel_dep(name = "rules_cc", version = "0.0.9")
-bazel_dep(name = "rules_pkg", version = "0.9.1")
+bazel_dep(name = "bazel_skylib", version = "1.7.1")
+bazel_dep(name = "platforms", version = "0.0.11")
+bazel_dep(name = "rules_cc", version = "0.1.1")
+bazel_dep(name = "rules_pkg", version = "1.0.1")
 bazel_dep(name = "rules_oci", version = "1.0.0")
 
 # Register module extensions

MODULE.bazel.lock

@@ -102,7 +102,7 @@ def swift_cc_toolchain_llvm20():
         build_file = Label("@rules_swiftnav//cc/toolchains/llvm20:llvm.BUILD.bzl"),
         url = AARCH64_DARWIN_LLVM20,
         strip_prefix = "LLVM-20.1.7-macOS-ARM64",
-        # TODO: Add sha256 hash for integrity
+        sha256 = "6aa75de00575ad0663183b00f00f39992ded611b5136e57649ace1e6a53c0d16",
     )
 
     maybe(

cc/repositories.bzl

@@ -66,6 +66,7 @@ filegroup(
             "lib/libclang*.a",
             "lib/liblld*.a",
         ],
+        allow_empty = True,
     ),
     # Do not include the .dylib files in the linker sandbox because they will
     # not be available at runtime. Any library linked from the toolchain should

cc/toolchains/llvm20/llvm.BUILD.bzl

@@ -0,0 +1 @@
+USE_BASEL_VERSION=8.3.1

examples/small_world/.bazeliskrc

@@ -0,0 +1,10 @@
+common --@rules_swiftnav//cc:enable_bzlmod=true
+
+coverage --experimental_generate_llvm_lcov
+coverage --combined_report=lcov
+
+# Work around for Mac: https://github.com/bazelbuild/bazel/issues/14970.
+# bazel coverage --config=cov_mac //...
+build:cov_mac --repo_env=GCOV=/Library/Developer/CommandLineTools/usr/bin/llvm-profdata
+build:cov_mac --test_env=LLVM_COV=/Library/Developer/CommandLineTools/usr/bin/llvm-cov
+build:cov_mac --copt=-ffile-compilation-dir=.

examples/small_world/.bazelrc

@@ -0,0 +1,2 @@
+cov.dat
+cov_html/