diff options
| -rw-r--r-- | src/fmt/fmt_test.go | 12 | ||||
| -rw-r--r-- | src/fmt/print.go | 28 |
2 files changed, 36 insertions, 4 deletions
diff --git a/src/fmt/fmt_test.go b/src/fmt/fmt_test.go index 059d09e1bf..28b7e0551a 100644 --- a/src/fmt/fmt_test.go +++ b/src/fmt/fmt_test.go @@ -832,6 +832,10 @@ var reorderTests = []struct { {"%[5]d %[2]d %d", SE{1, 2, 3}, "%!d(BADINDEX) 2 3"}, {"%d %[3]d %d", SE{1, 2}, "1 %!d(BADINDEX) 2"}, // Erroneous index does not affect sequence. {"%.[]", SE{}, "%!](BADINDEX)"}, // Issue 10675 + {"%.-3d", SE{42}, "%!-(int=42)3d"}, // TODO: Should this set return better error messages? + {"%2147483648d", SE{42}, "%!(NOVERB)%!(EXTRA int=42)"}, + {"%-2147483648d", SE{42}, "%!(NOVERB)%!(EXTRA int=42)"}, + {"%.2147483648d", SE{42}, "%!(NOVERB)%!(EXTRA int=42)"}, } func TestReorder(t *testing.T) { @@ -1158,14 +1162,20 @@ var startests = []struct { out string }{ {"%*d", args(4, 42), " 42"}, + {"%-*d", args(4, 42), "42 "}, + {"%*d", args(-4, 42), "42 "}, + {"%-*d", args(-4, 42), "42 "}, {"%.*d", args(4, 42), "0042"}, {"%*.*d", args(8, 4, 42), " 0042"}, {"%0*d", args(4, 42), "0042"}, - {"%-*d", args(4, 42), "42 "}, // erroneous {"%*d", args(nil, 42), "%!(BADWIDTH)42"}, + {"%*d", args(int(1e7), 42), "%!(BADWIDTH)42"}, + {"%*d", args(int(-1e7), 42), "%!(BADWIDTH)42"}, {"%.*d", args(nil, 42), "%!(BADPREC)42"}, + {"%.*d", args(-1, 42), "%!(BADPREC)42"}, + {"%.*d", args(int(1e7), 42), "%!(BADPREC)42"}, {"%*d", args(5, "foo"), "%!d(string= foo)"}, {"%*% %d", args(20, 5), "% 5"}, {"%*", args(4), "%!(NOVERB)"}, diff --git a/src/fmt/print.go b/src/fmt/print.go index d07835da49..8d3e97c3ab 100644 --- a/src/fmt/print.go +++ b/src/fmt/print.go @@ -285,15 +285,20 @@ func getField(v reflect.Value, i int) reflect.Value { return val } +// tooLarge reports whether the magnitude of the integer is +// too large to be used as a formatting width or precision. +func tooLarge(x int) bool { + const max int = 1e6 + return x > max || x < -max +} + // parsenum converts ASCII to integer. num is 0 (and isnum is false) if no number present. func parsenum(s string, start, end int) (num int, isnum bool, newi int) { if start >= end { return 0, false, end } for newi = start; newi < end && '0' <= s[newi] && s[newi] <= '9'; newi++ { - const maxInt32 = 1<<31 - 1 // 31 bits is plenty for a width. - max := maxInt32/10 - 1 - if num > max { + if tooLarge(num) { return 0, false, end // Overflow; crazy long number most likely. } num = num*10 + int(s[newi]-'0') @@ -1025,6 +1030,10 @@ func intFromArg(a []interface{}, argNum int) (num int, isInt bool, newArgNum int if argNum < len(a) { num, isInt = a[argNum].(int) newArgNum = argNum + 1 + if tooLarge(num) { + num = 0 + isInt = false + } } return } @@ -1119,9 +1128,17 @@ func (p *pp) doPrintf(format string, a []interface{}) { if i < end && format[i] == '*' { i++ p.fmt.wid, p.fmt.widPresent, argNum = intFromArg(a, argNum) + if !p.fmt.widPresent { p.buf.Write(badWidthBytes) } + + // We have a negative width, so take its value and ensure + // that the minus flag is set + if p.fmt.wid < 0 { + p.fmt.wid = -p.fmt.wid + p.fmt.minus = true + } afterIndex = false } else { p.fmt.wid, p.fmt.widPresent, i = parsenum(format, i, end) @@ -1140,6 +1157,11 @@ func (p *pp) doPrintf(format string, a []interface{}) { if i < end && format[i] == '*' { i++ p.fmt.prec, p.fmt.precPresent, argNum = intFromArg(a, argNum) + // Negative precision arguments don't make sense + if p.fmt.prec < 0 { + p.fmt.prec = 0 + p.fmt.precPresent = false + } if !p.fmt.precPresent { p.buf.Write(badPrecBytes) } |