vim-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.

9992237a3e

src/nvim/strings.c

@@ -1209,9 +1209,10 @@ int vim_vsnprintf(char *str, size_t str_m, const char *fmt, va_list ap,
             }
 
             if (fmt_spec == 'f' && abs_f > 1.0e307) {
+              const char inf_str[] = f < 0 ? "-inf" : "inf";
               // avoid a buffer overflow
-              memmove(tmp, "inf", sizeof("inf"));
+              memmove(tmp, inf_str, sizeof(inf_str) - 1);
-              str_arg_l = sizeof("inf") - 1;
+              str_arg_l = sizeof(inf_str) - 1;
             } else {
               format[0] = '%';
               int l = 1;
@@ -1234,6 +1235,23 @@ int vim_vsnprintf(char *str, size_t str_m, const char *fmt, va_list ap,
               str_arg_l = (size_t)snprintf(tmp, sizeof(tmp), format, f);
               assert(str_arg_l < sizeof(tmp));
 
+              // Be consistent: Change "1.#IND" to "nan" and
+              // "1.#INF" to "inf".
+              char *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;
                 char *tp;

src/nvim/testdir/test_expr.vim

@@ -201,12 +201,10 @@ 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', sqrt(-1.0)))
+  call assert_match('^nan$', printf('%f', 0.0/0.0))
-  call assert_match('^-\?nan$', printf('%f', 0.0/0.0))
 
   call assert_fails('echo printf("%f", "a")', 'E807:')
 endfunc

src/nvim/version.c

@@ -175,7 +175,7 @@ static int included_patches[] = {
   // 2269,
   // 2268,
   // 2267 NA
-  // 2266,
+  2266,
   2265,
   2264,
   // 2263,