diff --git a/stdlib/Printf/src/Printf.jl b/stdlib/Printf/src/Printf.jl index 9226d2c7fa5c6..8dacee5a1dc1b 100644 --- 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)