Add a test for link_depends using a custom target

test cases/common/152 link depends custom target/foo.c

@@ -0,0 +1,15 @@
+#include <stdio.h>
+
+int main() {
+  const char *fn = DEPFILE;
+  FILE *f = fopen(fn, "r");
+  if (!f) {
+    printf("could not open %s", fn);
+    return 1;
+  }
+  else {
+    printf("successfully opened %s", fn);
+  }
+
+  return 0;
+}

test cases/common/152 link depends custom target/make_file.py

@@ -0,0 +1,5 @@
+#!/usr/bin/env python3
+import sys
+
+with open(sys.argv[1], 'w') as f:
+    print('# this file does nothing', file=f)

test cases/common/152 link depends custom target/meson.build

@@ -0,0 +1,19 @@
+project('link_depends_custom_target', 'c')
+
+if meson.backend().startswith('vs')
+  # FIXME: Broken on the VS backends
+  error('MESON_SKIP_TEST see https://github.com/mesonbuild/meson/issues/1799')
+endif
+
+cmd = find_program('make_file.py')
+
+dep_file = custom_target('gen_dep',
+        command: [cmd, '@OUTPUT@'],
+        output: 'dep_file')
+
+exe = executable('foo', 'foo.c',
+        link_depends: dep_file,
+        c_args: ['-DDEPFILE="' + dep_file.full_path()+ '"'])
+
+# check that dep_file exists, which means that link_depends target ran
+test('runtest', exe)