tests: move tests for eqzero() to a new file

It's a bit silly to have a separate file that one short test, but this is the
last part of the test code that is misplaced, and here consistency beats
brevity.

TODO

@@ -72,8 +72,6 @@ Regularly:
 
 Janitorial Clean-ups:
 
-* Rearrange tests so that the various test-xyz.c match a specific src/basic/xyz.c again
-
 * rework mount.c and swap.c to follow proper state enumeration/deserialization
   semantics, like we do for device.c now
 

src/test/meson.build

@@ -217,6 +217,8 @@ tests += [
          [],
          [libm]],
 
+        [files('test-memory-util.c')],
+
         [files('test-mkdir.c')],
 
         [files('test-json.c'),

src/test/test-memory-util.c

@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "memory-util.h"
+#include "tests.h"
+
+TEST(eqzero) {
+        const uint32_t zeros[] = {0, 0, 0};
+        const uint32_t ones[] = {1, 1};
+        const uint32_t mixed[] = {0, 1, 0, 0, 0};
+        const uint8_t longer[] = {[55] = 255};
+
+        assert_se(eqzero(zeros));
+        assert_se(!eqzero(ones));
+        assert_se(!eqzero(mixed));
+        assert_se(!eqzero(longer));
+}
+
+DEFINE_TEST_MAIN(LOG_INFO);

src/test/test-util.c

@@ -1,17 +1,5 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
-#include <errno.h>
-
-#include "fileio.h"
-#include "fs-util.h"
-#include "limits-util.h"
-#include "memory-util.h"
-#include "missing_syscall.h"
-#include "parse-util.h"
-#include "process-util.h"
-#include "raw-clone.h"
-#include "rm-rf.h"
-#include "string-util.h"
 #include "tests.h"
 #include "util.h"
 
@@ -83,16 +71,4 @@ TEST(log2i) {
         assert_se(log2i(INT_MAX) == sizeof(int)*8-2);
 }
 
-TEST(eqzero) {
-        const uint32_t zeros[] = {0, 0, 0};
-        const uint32_t ones[] = {1, 1};
-        const uint32_t mixed[] = {0, 1, 0, 0, 0};
-        const uint8_t longer[] = {[55] = 255};
-
-        assert_se(eqzero(zeros));
-        assert_se(!eqzero(ones));
-        assert_se(!eqzero(mixed));
-        assert_se(!eqzero(longer));
-}
-
 DEFINE_TEST_MAIN(LOG_INFO);