add tests

Author: perazz

test/system/CMakeLists.txt

@@ -1,2 +1,3 @@
+ADDTEST(os)
 ADDTEST(sleep)
 ADDTEST(subprocess)

test/system/test_os.f90

@@ -0,0 +1,70 @@
+module test_os
+    use testdrive, only : new_unittest, unittest_type, error_type, check, skip_test
+    use stdlib_system, only: get_runtime_os, OS_WINDOWS, OS_UNKNOWN, OS_TYPE, is_windows
+
+    implicit none
+
+contains
+
+    !> Collect all exported unit tests
+    subroutine collect_suite(testsuite)
+        !> Collection of tests
+        type(unittest_type), allocatable, intent(out) :: testsuite(:)
+
+        testsuite = [ &
+            new_unittest('test_get_runtime_os', test_get_runtime_os), &
+            new_unittest('test_is_windows', test_is_windows) &
+        ]
+    end subroutine collect_suite
+
+    subroutine test_get_runtime_os(error)
+        type(error_type), allocatable, intent(out) :: error
+        integer :: os
+
+        !> Get current OS
+        os = get_runtime_os()
+
+        call check(error, os /= OS_UNKNOWN, "running on an unknown/unsupported OS")
+        
+    end subroutine test_get_runtime_os
+
+    !> If running on Windows (_WIN32 macro is defined), test that the appropriate OS flag is returned
+    subroutine test_is_windows(error)
+        type(error_type), allocatable, intent(out) :: error
+        integer :: os_cached, os_runtime
+        
+        call check(error, OS_TYPE()==OS_WINDOWS .eqv. is_windows(), &
+                   "Cached OS type does not match _WIN32 macro presence")
+
+    end subroutine test_is_windows
+
+
+end module test_os
+
+program tester
+    use, intrinsic :: iso_fortran_env, only : error_unit
+    use testdrive, only : run_testsuite, new_testsuite, testsuite_type
+    use test_os, only : collect_suite
+
+    implicit none
+
+    integer :: stat, is
+    type(testsuite_type), allocatable :: testsuites(:)
+    character(len=*), parameter :: fmt = '("#", *(1x, a))'
+
+    stat = 0
+
+    testsuites = [ &
+        new_testsuite("os", collect_suite) &
+    ]
+
+    do is = 1, size(testsuites)
+        write(error_unit, fmt) "Testing:", testsuites(is)%name
+        call run_testsuite(testsuites(is)%collect, error_unit, stat)
+    end do
+
+    if (stat > 0) then
+        write(error_unit, '(i0, 1x, a)') stat, "test(s) failed!"
+        error stop
+    end if
+end program