test: Test wctype functions by comparing with native C library

Check every unicode code point using every wctype function and make
sure the picolibc versions matches the native C library implemetation.
This makes some bold assumptions that picolibc and the native C
library are using the same Unicode tables.

Signed-off-by: Keith Packard <[email protected]>

Author: keith-packard

test/meson.build

@@ -708,6 +708,31 @@ if enable_native_tests
 		    link_args: native_c_args))
   endforeach
 
+  if newlib_mb
+    diff = find_program('diff', required: false)
+
+    if diff.found()
+      wctype = executable('test-wctype', 'test-wctype.c',
+                          c_args: _c_args,
+                          link_args: _link_args,
+                          objects: _objs,
+                          link_depends: _link_depends + _libs,
+                          include_directories: inc)
+
+      wctype_native = executable('test-wctype-native', 'test-wctype.c',
+                                 c_args: native_c_args,
+                                 link_args: native_c_args)
+
+      wctype_out = custom_target ('wctype-out', output: 'wctype-out',
+                                  command: [wctype, '@OUTPUT@'])
+
+      wctype_native_out = custom_target ('wctype-native-out', output: 'wctype-native-out',
+                                         command: [wctype_native, '@OUTPUT@'])
+
+      test('wctype-compare', diff, args: [wctype_out, wctype_native_out])
+    endif
+  endif
+       
 endif
 
 subdir('libc-testsuite')

test/test-wctype.c

@@ -0,0 +1,94 @@
+/*
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright © 2024 Keith Packard
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ *    copyright notice, this list of conditions and the following
+ *    disclaimer in the documentation and/or other materials provided
+ *    with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <wctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <locale.h>
+
+static struct {
+    char *n;
+    int (*f)(wint_t);
+} funcs[] = {
+    { .n = "alnum", iswalnum },
+    { .n = "alpha", iswalpha },
+    { .n = "blank", iswblank },
+    { .n = "cntrl", iswcntrl },
+    { .n = "digit", iswdigit },
+    { .n = "graph", iswgraph },
+    { .n = "lower", iswlower },
+    { .n = "print", iswprint },
+    { .n = "punct", iswpunct },
+    { .n = "space", iswspace },
+    { .n = "upper", iswupper },
+    { .n = "xdigit", iswxdigit },
+};
+
+#define NFUNC sizeof(funcs)/sizeof(funcs[0])
+
+int main(int argc, char **argv)
+{
+    wchar_t     c;
+    unsigned    f;
+    FILE        *out = stdout;
+
+    if (argc > 1) {
+        out = fopen(argv[1], "w");
+        if (!out) {
+            perror(argv[1]);
+            exit(1);
+        }
+    }
+
+    c = 0x0000;
+    setlocale(LC_ALL, "C.UTF-8");
+    for (;;) {
+        fprintf(out, "0x%04x", c);
+        for (f = 0; f < NFUNC; f++)
+            fprintf(out, "%6.6s ", funcs[f].f(c) ? funcs[f].n : "      ");
+
+        fprintf(out, "\n");
+#if __SIZEOF_WCHAR_T__ == 2
+        if (c == 0xffff)
+            break;
+#else
+        if (c == 0xe01ef)
+            break;
+#endif
+        c++;
+    }
+    fflush(out);
+    return 0;
+}