inf or nan parsing should ignore leading spaces

src/support/strtod.c

@@ -118,9 +118,16 @@ JL_DLLEXPORT double jl_strtod_c(const char *nptr, char **endptr)
 
     decimal_point_pos = NULL;
 
+    p = nptr;
+
+    /* parse leading spaces */
+    while (isspace((unsigned char)*p)) {
+        p++;
+    }
+
     /* Parse infinities and nans */
-    val = parse_inf_or_nan(nptr, endptr);
-    if (*endptr != nptr)
+    val = parse_inf_or_nan(p, endptr);
+    if (*endptr != p)
         return val;
 
     /* Set errno to zero, so that we can distinguish zero results
@@ -130,12 +137,6 @@ JL_DLLEXPORT double jl_strtod_c(const char *nptr, char **endptr)
     /* We process the optional sign manually, then pass the remainder to
        the system strtod.  This ensures that the result of an underflow
        has the correct sign.  */
-    p = nptr;
-
-    /* parse leading spaces */
-    while (isspace((unsigned char)*p)) {
-        p++;
-    }
 
     /* Process leading sign, if present */
     if (*p == '-') {

test/parse.jl

@@ -338,3 +338,10 @@ end
     # Ensure dotting binary doesn't break dotting unary
     @test Meta.parse(".~[1,2]") == Expr(:call, :.~, Expr(:vect, 1, 2))
 end
+
+@testset "inf and nan parsing" begin
+    for (v,vs) in ((NaN,"nan"), (Inf,"inf"), (Inf,"infinity")), sbefore in ("", "  "), safter in ("", "  "), sign in (+, -), case in (lowercase, uppercase)
+        s = case(string(sbefore, sign, vs, safter))
+        @test isequal(parse(Float64, s), sign(v))
+    end
+end