Add isinf/isnan check for %g/%G formatting

JuliaLang · Jul 20, 2021 · 860f994 · 860f994
1 parent 5a16805
commit 860f994
Showing 1 changed file with 23 additions and 19 deletions.
diff --git a/stdlib/Printf/src/Printf.jl b/stdlib/Printf/src/Printf.jl
@@ -424,27 +424,31 @@ const __BIG_FLOAT_MAX__ = 8192
     elseif T == Val{'f'} || T == Val{'F'}
         newpos = Ryu.writefixed(buf, pos, x, prec, plus, space, hash, UInt8('.'))
     elseif T == Val{'g'} || T == Val{'G'}
-        # C11-compliant general format
-        prec = prec == 0 ? 1 : prec
-        # format the value in scientific notation and parse the exponent part
-        exp = let p = Ryu.writeexp(buf, pos, x, prec)
-            b1, b2, b3, b4 = buf[p-4], buf[p-3], buf[p-2], buf[p-1]
-            Z = UInt8('0')
-            if b1 == UInt8('e')
-                # two-digit exponent
-                sign = b2 == UInt8('+') ? 1 : -1
-                exp = 10 * (b3 - Z) + (b4 - Z)
+        if isinf(x) || isnan(x)
+            newpos = Ryu.writeshortest(buf, pos, x, plus, space)
+        else
+            # C11-compliant general format
+            prec = prec == 0 ? 1 : prec
+            # format the value in scientific notation and parse the exponent part
+            exp = let p = Ryu.writeexp(buf, pos, x, prec)
+                b1, b2, b3, b4 = buf[p-4], buf[p-3], buf[p-2], buf[p-1]
+                Z = UInt8('0')
+                if b1 == UInt8('e')
+                    # two-digit exponent
+                    sign = b2 == UInt8('+') ? 1 : -1
+                    exp = 10 * (b3 - Z) + (b4 - Z)
+                else
+                    # three-digit exponent
+                    sign = b1 == UInt8('+') ? 1 : -1
+                    exp = 100 * (b2 - Z) + 10 * (b3 - Z) + (b4 - Z)
+                end
+                flipsign(exp, sign)
+            end
+            if -4 ≤ exp < prec
+                newpos = Ryu.writefixed(buf, pos, x, prec - (exp + 1), plus, space, hash, UInt8('.'), !hash)
             else
-                # three-digit exponent
-                sign = b1 == UInt8('+') ? 1 : -1
-                exp = 100 * (b2 - Z) + 10 * (b3 - Z) + (b4 - Z)
+                newpos = Ryu.writeexp(buf, pos, x, prec - 1, plus, space, hash, T == Val{'g'} ? UInt8('e') : UInt8('E'), UInt8('.'), !hash)
             end
-            flipsign(exp, sign)
-        end
-        if -4 ≤ exp < prec
-            newpos = Ryu.writefixed(buf, pos, x, prec - (exp + 1), plus, space, hash, UInt8('.'), !hash)
-        else
-            newpos = Ryu.writeexp(buf, pos, x, prec - 1, plus, space, hash, T == Val{'g'} ? UInt8('e') : UInt8('E'), UInt8('.'), !hash)
         end
     elseif T == Val{'a'} || T == Val{'A'}
         x, neg = x < 0 || x === -Base.zero(x) ? (-x, true) : (x, false)