Support building with Bazel (#1033)

Adds support for building with Bazel. If merged, I can push this to
https://registry.bazel.build/ when a new release is cut :)

---------

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
Co-authored-by: Caleb Zulawski <caleb.zulawski@caci.com>
Co-authored-by: Henry Schreiner <henryschreineriii@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

.github/workflows/tests.yml

@@ -169,6 +169,18 @@ jobs:
       - name: Test
         run: meson test -C build-meson
 
+  bazel-build:
+    name: Bazel build
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Build
+        run: bazel build //...
+
+      - name: Test
+        run: bazel test --test_output=errors //...
+
   install:
     name: install tests
     runs-on: ubuntu-latest

.gitignore

@@ -10,6 +10,8 @@ a.out*
 /html/*
 !/meson.build
 /CMakeUserPresets.json
+/bazel-*
+/MODULE.bazel.lock
 
 /node_modules/*
 /package.json

BUILD.bazel

@@ -0,0 +1,8 @@
+cc_library(
+    name = "cli11",
+    srcs = glob(["src/**/*.cpp"]),
+    hdrs = glob(["include/**/*.hpp"]),
+    local_defines = ["CLI11_COMPILE"],
+    strip_include_prefix = "/include",
+    visibility = ["//visibility:public"],
+)

MODULE.bazel

@@ -0,0 +1,3 @@
+module(name = "cli11")
+
+bazel_dep(name = "catch2", version = "3.5.4", dev_dependency = True)

tests/BUILD.bazel

@@ -0,0 +1,75 @@
+cc_binary(
+    name = "ensure_utf8",
+    srcs = ["applications/ensure_utf8.cpp"],
+    deps = ["//:cli11"],
+)
+
+cc_binary(
+    name = "ensure_utf8_twice",
+    srcs = ["applications/ensure_utf8_twice.cpp"],
+    deps = ["//:cli11"],
+)
+
+cc_library(
+    name = "catch_main",
+    srcs = ["main.cpp"],
+    hdrs = ["catch.hpp"],
+    defines = ["CLI11_CATCH3"],
+    deps = ["@catch2//:catch2_main"],
+)
+
+cc_test(
+    name = "AppTest",
+    srcs = [
+        "AppTest.cpp",
+        "app_helper.hpp",
+    ],
+    data = [
+        "ensure_utf8",
+        "ensure_utf8_twice",
+    ],
+    local_defines = [
+        'CLI11_ENSURE_UTF8_EXE=\\"$(rootpath ensure_utf8)\\"',
+        'CLI11_ENSURE_UTF8_TWICE_EXE=\\"$(rootpath ensure_utf8_twice)\\"',
+    ],
+    deps = [
+        "catch_main",
+        "//:cli11",
+        "@catch2",
+    ],
+)
+
+[
+    cc_test(
+        name = test,
+        srcs = [
+            test + ".cpp",
+            "app_helper.hpp",
+        ],
+        deps = [
+            "catch_main",
+            "//:cli11",
+            "@catch2",
+        ],
+    )
+    for test in [
+        "HelpersTest",
+        "ConfigFileTest",
+        "OptionTypeTest",
+        "SimpleTest",
+        "SetTest",
+        "TransformTest",
+        "CreationTest",
+        "SubcommandTest",
+        "HelpTest",
+        "FormatterTest",
+        "NewParseTest",
+        "OptionalTest",
+        "DeprecatedTest",
+        "StringParseTest",
+        "ComplexTypeTest",
+        "TrueFalseTest",
+        "OptionGroupTest",
+        "EncodingTest",
+    ]
+]

tests/CMakeLists.txt

@@ -106,7 +106,7 @@ file(
   GLOB_RECURSE DATA_FILES
   LIST_DIRECTORIES false
   RELATIVE "${CMAKE_CURRENT_SOURCE_DIR}"
-  "${CMAKE_CURRENT_SOURCE_DIR}/data/*")
+  "${CMAKE_CURRENT_SOURCE_DIR}/data/*" "${CMAKE_CURRENT_SOURCE_DIR}/tests/.gitkeep")
 
 foreach(DATA_FILE IN LISTS DATA_FILES)
   add_custom_command(

tests/HelpersTest.cpp

@@ -522,7 +522,7 @@ TEST_CASE("Validators: FileIsDir", "[helpers]") {
 }
 
 TEST_CASE("Validators: DirectoryExists", "[helpers]") {
-    std::string mydir{"../tests"};
+    std::string mydir{"tests"};
     CHECK(CLI::ExistingDirectory(mydir).empty());
 }
 
@@ -543,7 +543,7 @@ TEST_CASE("Validators: DirectoryIsFile", "[helpers]") {
 }
 
 TEST_CASE("Validators: PathExistsDir", "[helpers]") {
-    std::string mydir{"../tests"};
+    std::string mydir{"tests"};
     CHECK(CLI::ExistingPath(mydir).empty());
 }
 
@@ -665,7 +665,7 @@ TEST_CASE("Validators: CombinedPaths", "[helpers]") {
     bool ok = static_cast<bool>(std::ofstream(myfile.c_str()).put('a'));  // create file
     CHECK(ok);
 
-    std::string dir{"../tests"};
+    std::string dir{"tests"};
     std::string notpath{"nondirectory"};
 
     auto path_or_dir = CLI::ExistingPath | CLI::ExistingDirectory;