Add test for conditional Objective-C support

Closes #183

Author: mrexodia

docs/examples/objective-c.md

@@ -0,0 +1,30 @@
+---
+# Automatically generated from tests/objective-c/cmake.toml - DO NOT EDIT
+layout: default
+title: Objective-C
+permalink: /examples/objective-c
+parent: Examples
+nav_order: 11
+---
+
+# Objective-C
+
+Add Objective-C sources on Apple platforms:
+
+```toml
+[project]
+name = "objective-c"
+description = "Objective-C"
+languages = ["C"]
+apple.languages = ["OBJC"]
+
+[target.hello]
+type = "executable"
+sources = ["src/main.c"]
+apple.sources = ["src/apple.m"]
+apple.link-libraries = ["$<LINK_LIBRARY:FRAMEWORK,Foundation>"]
+```
+
+
+
+<sup><sub>This page was automatically generated from [tests/objective-c/cmake.toml](https://github.com/build-cpp/cmkr/tree/main/tests/objective-c/cmake.toml).</sub></sup>

tests/CMakeLists.txt

@@ -65,3 +65,9 @@ name = "relative-paths"
 working-directory = "relative-paths"
 command = "$<TARGET_FILE:cmkr>"
 arguments = ["build"]
+
+[[test]]
+name = "objective-c"
+working-directory = "objective-c"
+command = "$<TARGET_FILE:cmkr>"
+arguments = ["build"]

tests/cmake.toml

@@ -0,0 +1,13 @@
+# Add Objective-C sources on Apple platforms:
+
+[project]
+name = "objective-c"
+description = "Objective-C"
+languages = ["C"]
+apple.languages = ["OBJC"]
+
+[target.hello]
+type = "executable"
+sources = ["src/main.c"]
+apple.sources = ["src/apple.m"]
+apple.link-libraries = ["$<LINK_LIBRARY:FRAMEWORK,Foundation>"]

tests/objective-c/cmake.toml

@@ -0,0 +1,7 @@
+#import <Foundation/Foundation.h>
+
+void platform_specific() {
+  NSFileHandle *stdout = [NSFileHandle fileHandleWithStandardOutput];
+  NSString *message = @"Hello from Objective-C!\n";
+  [stdout writeData:[message dataUsingEncoding:NSUTF8StringEncoding] error:nil];
+}

tests/objective-c/src/apple.m

@@ -0,0 +1,14 @@
+#include <stdio.h>
+
+#ifdef __APPLE__
+void platform_specific();
+#else
+void platform_specific() {
+    puts("This is not an Apple platform.");
+}
+#endif
+
+int main() {
+    platform_specific();
+    return 0;
+}