patch 7.4.2266

Problem:    printf() test fails on Windows. "-inf" is not used.
Solution:   Check for Windows-specific values for "nan".  Add sign to "inf"
            when appropriate.

Author: brammool

src/message.c

@@ -4701,6 +4701,7 @@ vim_vsnprintf(
 		    char	format[40];
 		    int		l;
 		    int		remove_trailing_zeroes = FALSE;
+		    char	*s;
 
 		    f =
 #  if defined(FEAT_EVAL)
@@ -4730,8 +4731,16 @@ vim_vsnprintf(
 			    )
 		    {
 			/* Avoid a buffer overflow */
-			strcpy(tmp, "inf");
-			str_arg_l = 3;
+			if (f < 0)
+			{
+			    strcpy(tmp, "-inf");
+			    str_arg_l = 4;
+			}
+			else
+			{
+			    strcpy(tmp, "inf");
+			    str_arg_l = 3;
+			}
 		    }
 		    else
 		    {
@@ -4753,6 +4762,22 @@ vim_vsnprintf(
 			format[l + 1] = NUL;
 			str_arg_l = sprintf(tmp, format, f);
 
+			/* Be consistent: Change "1.#IND" to "nan" and
+			 * "1.#INF" to "inf". */
+			s = *tmp == '-' ? tmp + 1 : tmp;
+			if (STRNCMP(s, "1.#INF", 6) == 0)
+			    STRCPY(s, "inf");
+			else if (STRNCMP(s, "1.#IND", 6) == 0)
+			    STRCPY(s, "nan");
+
+			/* Remove sign before "nan". */
+			if (STRNCMP(tmp, "-nan", 4) == 0)
+			    STRCPY(tmp, "nan");
+
+			/* Add sign before "inf" if needed. */
+			if (isinf(f) == -1 && STRNCMP(tmp, "inf", 3) == 0)
+			    STRCPY(tmp, "-inf");
+
 			if (remove_trailing_zeroes)
 			{
 			    int i;

src/testdir/test_expr.vim

@@ -204,12 +204,10 @@ function Test_printf_float()
 
     call assert_equal('inf', printf('%f', 1.0/0.0))
 
-    " This prints inf but shouldn't it print -inf instead?
-    call assert_match('^-\?inf$', printf('%f', -1.0/0.0))
+    call assert_match('^-inf$', printf('%f', -1.0/0.0))
 
-    " This prints -nan but shouldn't it print nan instead?
-    call assert_match('^-\?nan$', printf('%f', sqrt(-1.0)))
-    call assert_match('^-\?nan$', printf('%f', 0.0/0.0))
+    call assert_match('^nan$', printf('%f', sqrt(-1.0)))
+    call assert_match('^nan$', printf('%f', 0.0/0.0))
 
     call assert_fails('echo printf("%f", "a")', 'E807:')
   endif

src/version.c

@@ -763,6 +763,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2266,
 /**/
     2265,
 /**/