gtestutils: Improve g_assert_cmpuint

While x86_64 has enough precision in long double to do a round trip
from guint64 to long double and back, this is platform-specific, and
is a disservice to users trying to debug failing unit tests on other
architectures where it loses precision for g_assert_cmp{int,uint,hex}.
See also https://bugzilla.gnome.org/show_bug.cgi?id=788385 which
mentions having to add casts to specifically silence the compiler on
platforms where the precision loss occurs.

Meanwhile, g_assert_cmpuint() does an unsigned comparison, but outputs
signed values if the comparison fails, which is confusing.

Fix both issues by introducing a new g_assertion_message_cmpint()
function with a new 'u' numtype.  For backwards compatibility, the
macros still call into the older g_assertion_message_cmpnum() when not
targetting 2.78, and that function still works when passed 'i' and 'x'
types even though code compiled for 2.78 and later will never invoke
it with numtype anything other than 'f'.  Note that g_assert_cmpmem
can also take advantage of the new code, even though in practice,
comparison between two size_t values representing array lengths that
can actually be compiled is unlikely to have ever hit the precision
loss.  The macros in signals.c test code does not have to worry about
versioning, since it is not part of the glib library proper.

Closes #2997
Signed-off-by: Eric Blake <eblake@redhat.com>

4 files changed, 81 insertions, 4 deletions

diff --git a/docs/reference/glib/glib-sections.txt.in b/docs/reference/glib/glib-sections.txt.in
index a674f8320..012aeef77 100644
--- a/docs/reference/glib/glib-sections.txt.in
+++ b/docs/reference/glib/glib-sections.txt.in
@@ -3401,6 +3401,7 @@ g_test_trap_assertions
 g_assertion_message
 g_assertion_message_expr
 g_assertion_message_cmpstr
+g_assertion_message_cmpint
 g_assertion_message_cmpnum
 g_assertion_message_error
 g_test_assert_expected_messages_internal
diff --git a/glib/gtestutils.c b/glib/gtestutils.c
index d5cf23683..0164804a9 100644
--- a/glib/gtestutils.c
+++ b/glib/gtestutils.c
@@ -3487,6 +3487,29 @@ g_assertion_message_expr (const char     *domain,
 }
 
 void
+g_assertion_message_cmpint (const char     *domain,
+                            const char     *file,
+                            int             line,
+                            const char     *func,
+                            const char     *expr,
+                            guint64         arg1,
+                            const char     *cmp,
+                            guint64         arg2,
+                            char            numtype)
+{
+  char *s = NULL;
+
+  switch (numtype)
+    {
+    case 'i':   s = g_strdup_printf ("assertion failed (%s): (%" G_GINT64_MODIFIER "i %s %" G_GINT64_MODIFIER "i)", expr, (gint64) arg1, cmp, (gint64) arg2); break;
+    case 'u':   s = g_strdup_printf ("assertion failed (%s): (%" G_GINT64_MODIFIER "u %s %" G_GINT64_MODIFIER "u)", expr, arg1, cmp, arg2); break;
+    case 'x':   s = g_strdup_printf ("assertion failed (%s): (0x%08" G_GINT64_MODIFIER "x %s 0x%08" G_GINT64_MODIFIER "x)", expr, arg1, cmp, arg2); break;
+    }
+  g_assertion_message (domain, file, line, func, s);
+  g_free (s);
+}
+
+void
 g_assertion_message_cmpnum (const char     *domain,
                             const char     *file,
                             int             line,
@@ -3501,8 +3524,10 @@ g_assertion_message_cmpnum (const char     *domain,
 
   switch (numtype)
     {
-    case 'i':   s = g_strdup_printf ("assertion failed (%s): (%" G_GINT64_MODIFIER "i %s %" G_GINT64_MODIFIER "i)", expr, (gint64) arg1, cmp, (gint64) arg2); break;
-    case 'x':   s = g_strdup_printf ("assertion failed (%s): (0x%08" G_GINT64_MODIFIER "x %s 0x%08" G_GINT64_MODIFIER "x)", expr, (guint64) arg1, cmp, (guint64) arg2); break;
+    case 'i':
+    case 'x':
+      /* Backwards compatibility to apps compiled before 2.78 */
+      g_assertion_message_cmpint (domain, file, line, func, expr, (guint64) arg1, cmp, (guint64) arg2, numtype); break;
     case 'f':   s = g_strdup_printf ("assertion failed (%s): (%.9g %s %.9g)", expr, (double) arg1, cmp, (double) arg2); break;
       /* ideally use: floats=%.7g double=%.17g */
     }
diff --git a/glib/gtestutils.h b/glib/gtestutils.h
index 86ee4e521..9406ff0d8 100644
--- a/glib/gtestutils.h
+++ b/glib/gtestutils.h
@@ -49,6 +49,26 @@ typedef void (*GTestFixtureFunc) (gpointer      fixture,
                                                g_assertion_message_cmpstr (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
                                                  #s1 " " #cmp " " #s2, __s1, #cmp, __s2); \
                                         } G_STMT_END
+#if GLIB_VERSION_MIN_REQUIRED >= GLIB_VERSION_2_78
+#define g_assert_cmpint(n1, cmp, n2)    G_STMT_START { \
+                                             gint64 __n1 = (n1), __n2 = (n2); \
+                                             if (__n1 cmp __n2) ; else \
+                                               g_assertion_message_cmpint (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
+                                                 #n1 " " #cmp " " #n2, __n1, #cmp, __n2, 'i'); \
+                                        } G_STMT_END
+#define g_assert_cmpuint(n1, cmp, n2)   G_STMT_START { \
+                                             guint64 __n1 = (n1), __n2 = (n2); \
+                                             if (__n1 cmp __n2) ; else \
+                                               g_assertion_message_cmpint (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
+                                                 #n1 " " #cmp " " #n2, __n1, #cmp, __n2, 'u'); \
+                                        } G_STMT_END
+#define g_assert_cmphex(n1, cmp, n2)    G_STMT_START { \
+                                             guint64 __n1 = (n1), __n2 = (n2); \
+                                             if (__n1 cmp __n2) ; else \
+                                               g_assertion_message_cmpint (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
+                                                 #n1 " " #cmp " " #n2, __n1, #cmp, __n2, 'x'); \
+                                        } G_STMT_END
+#else /* GLIB_VERSION_MIN_REQUIRED < GLIB_VERSION_2_78 */
 #define g_assert_cmpint(n1, cmp, n2)    G_STMT_START { \
                                              gint64 __n1 = (n1), __n2 = (n2); \
                                              if (__n1 cmp __n2) ; else \
@@ -67,6 +87,7 @@ typedef void (*GTestFixtureFunc) (gpointer      fixture,
                                                g_assertion_message_cmpnum (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
                                                  #n1 " " #cmp " " #n2, (long double) __n1, #cmp, (long double) __n2, 'x'); \
                                         } G_STMT_END
+#endif /* GLIB_VERSION_MIN_REQUIRED >= GLIB_VERSION_2_78 */
 #define g_assert_cmpfloat(n1,cmp,n2)    G_STMT_START { \
                                              long double __n1 = (long double) (n1), __n2 = (long double) (n2); \
                                              if (__n1 cmp __n2) ; else \
@@ -80,6 +101,25 @@ typedef void (*GTestFixtureFunc) (gpointer      fixture,
                                                g_assertion_message_cmpnum (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
                                                  #n1 " == " #n2 " (+/- " #epsilon ")", __n1, "==", __n2, 'f'); \
                                         } G_STMT_END
+#if GLIB_VERSION_MIN_REQUIRED >= GLIB_VERSION_2_78
+#define g_assert_cmpmem(m1, l1, m2, l2) G_STMT_START {\
+                                             gconstpointer __m1 = m1, __m2 = m2; \
+                                             size_t __l1 = (size_t) l1, __l2 = (size_t) l2; \
+                                             if (__l1 != 0 && __m1 == NULL) \
+                                               g_assertion_message (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
+                                                                    "assertion failed (" #l1 " == 0 || " #m1 " != NULL)"); \
+                                             else if (__l2 != 0 && __m2 == NULL) \
+                                               g_assertion_message (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
+                                                                    "assertion failed (" #l2 " == 0 || " #m2 " != NULL)"); \
+                                             else if (__l1 != __l2) \
+                                               g_assertion_message_cmpint (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
+                                                                           #l1 " (len(" #m1 ")) == " #l2 " (len(" #m2 "))", \
+                                                                           __l1, "==", __l2, 'u'); \
+                                             else if (__l1 != 0 && __m2 != NULL && memcmp (__m1, __m2, __l1) != 0) \
+                                               g_assertion_message (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
+                                                                    "assertion failed (" #m1 " == " #m2 ")"); \
+                                        } G_STMT_END
+#else /* GLIB_VERSION_MIN_REQUIRED < GLIB_VERSION_2_78 */
 #define g_assert_cmpmem(m1, l1, m2, l2) G_STMT_START {\
                                              gconstpointer __m1 = m1, __m2 = m2; \
                                              size_t __l1 = (size_t) l1, __l2 = (size_t) l2; \
@@ -97,6 +137,7 @@ typedef void (*GTestFixtureFunc) (gpointer      fixture,
                                                g_assertion_message (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
                                                                     "assertion failed (" #m1 " == " #m2 ")"); \
                                         } G_STMT_END
+#endif /* GLIB_VERSION_MIN_REQUIRED >= GLIB_VERSION_2_78 */
 #define g_assert_cmpvariant(v1, v2) \
   G_STMT_START \
   { \
@@ -567,6 +608,16 @@ void    g_assertion_message_cmpstrv     (const char         *domain,
                                          const char * const *arg1,
                                          const char * const *arg2,
                                          gsize               first_wrong_idx) G_ANALYZER_NORETURN;
+GLIB_AVAILABLE_IN_2_78
+void    g_assertion_message_cmpint      (const char     *domain,
+                                         const char     *file,
+                                         int             line,
+                                         const char     *func,
+                                         const char     *expr,
+                                         guint64         arg1,
+                                         const char     *cmp,
+                                         guint64         arg2,
+                                         char            numtype) G_ANALYZER_NORETURN;
 GLIB_AVAILABLE_IN_ALL
 void    g_assertion_message_cmpnum      (const char     *domain,
                                          const char     *file,
diff --git a/gobject/tests/signals.c b/gobject/tests/signals.c
index ef52255cd..ec9a584ca 100644
--- a/gobject/tests/signals.c
+++ b/gobject/tests/signals.c
@@ -4,13 +4,13 @@
 #define g_assert_cmpflags(type,n1, cmp, n2) G_STMT_START { \
                                                type __n1 = (n1), __n2 = (n2); \
                                                if (__n1 cmp __n2) ; else \
-                                                 g_assertion_message_cmpnum (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
+                                                 g_assertion_message_cmpint (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
                                                                              #n1 " " #cmp " " #n2, __n1, #cmp, __n2, 'i'); \
                                             } G_STMT_END
 #define g_assert_cmpenum(type,n1, cmp, n2) G_STMT_START { \
                                                type __n1 = (n1), __n2 = (n2); \
                                                if (__n1 cmp __n2) ; else \
-                                                 g_assertion_message_cmpnum (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
+                                                 g_assertion_message_cmpint (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, \
                                                                              #n1 " " #cmp " " #n2, __n1, #cmp, __n2, 'i'); \
                                             } G_STMT_END