Separate unicode formatting into its own fmt_unicode function.
Remove the fmtUnicode wrapper and the f.unicode and f.uniQuote
flags that are not needed anymore. Remove mangling and restoring
of the precision and sharp flags.
Removes the buffer copy needed for %#U by moving
the character encoding before the number encoding.
Changes the behavior of plus and space flag to have
no effect instead of printing a plus or space before "U+".
Always print at least four digits after "U+"
even if precision is set to less than 4.
Change-Id: If9a0ee79e9eca2c76f06a4e0fdd75d98393899ac
Reviewed-on: https://go-review.googlesource.com/20574
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Use The fmt internal buffer for character formatting instead of
the pp Printer rune decoding buffer.
Uses an uint64 instead of int64 argument to fmt_c and fmt_qc for easier
range checks since no valid runes are represented by negative numbers or
are above 0x10ffff.
Add range checks to fmt_c and fmt_qc to guarantee that a RuneError
character is returned by the functions for any invalid code point
in range uint64. For invalid code points in range utf8.MaxRune
the used utf8 and strconv functions already return a RuneError.
Change-Id: I9772f804dfcd79c3826fa7f6c5ebfbf4b5304a51
Reviewed-on: https://go-review.googlesource.com/20373
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Remove check for %p and %T in printValue.
These verbs are not recursive and are handled already in
printArg which is called on any argument before printValue.
Format the type string for %T directly instead of invoking
the more complex printArg with %s on the type string.
Decouple the %T tests from variables declared in scan_test.go.
Change-Id: Ibd51566bd4cc1a260ce6d052f36382ed05020b48
Reviewed-on: https://go-review.googlesource.com/20622
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Do a reset of the fmt flags before printing the extra argument
error message to prevent a malformed printing of extra arguments.
Regroup tests for extra argument error strings.
Change-Id: Ifd97f5ca36f6c97ed5a380d975cf154d17997d3f
Reviewed-on: https://go-review.googlesource.com/20571
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Use constants instead of dynamically computed values to determine
the bit sizes of types similar to how strconv and other packages
directly compute these sizes. Move these constants near the code
that uses them.
Change-Id: I78d113b7e697466097e32653975df5990380c2c1
Reviewed-on: https://go-review.googlesource.com/20514
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Treat the verb %X in the same special way as %q, %s and %x
are for arrays and slices with byte type elements.
Modify input for tests so the result of %x and %X is distinct.
Change-Id: I38d227755e98c7fad5e4adc2f603c6873aa910fd
Reviewed-on: https://go-review.googlesource.com/20516
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Uses a switch statement for direct format function selection
similar to other types verb handling in fmt.
Applies padding also to nil pointers formatted with %v.
Guards against "slice bounds out of range" panic in TestSprintf
when a pointer test results in a formatted string s
that is shorter than the index i the pointer should appear in.
Adds more and rearranges tests.
Fixes#14712Fixes#14714
Change-Id: Iaf5ae37b7e6ba7d27d528d199f2b2eb9d5829b8c
Reviewed-on: https://go-review.googlesource.com/20371
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Removes specialized functions for each verb and float/complex size
and replaces them with generic variants fmtFloat and
fmtComplex similar to other generic fmt functions.
Simplifies the complex formatting by relying on fmtFloat
to handle the verb and default precision selection.
Complex imaginary formatting does not need to clear the f.space flag
because the set f.plus flag will force a sign instead of a space.
Sets default precision for %b to -1 (same as %g and %G)
since precision for %b has no affect in strconv.AppendFloat.
Add more tests and group them a bit better.
Use local copies of +Inf,-Inf and NaN instead
of math package functions for testing.
Saves around 8kb in the go binary.
name old time/op new time/op delta
SprintfFloat-2 200ns ± 4% 196ns ± 4% -1.55% (p=0.007 n=20+20)
SprintfComplex-2 569ns ± 4% 570ns ± 3% ~ (p=0.804 n=20+20)
Change-Id: I36d35dab6f835fc2bd2c042ac97705868eb2446f
Reviewed-on: https://go-review.googlesource.com/20252
Reviewed-by: Rob Pike <r@golang.org>
Run-TryBot: Rob Pike <r@golang.org>
Instead of calling printArg in fmtBytes to format each byte call
the byte formatting functions directly since it is known each
element is of type byte.
Add more tests for byte slice and array formatting.
name old time/op new time/op delta
SprintfBytes-2 843ns ±16% 417ns ±11% -50.58% (p=0.000 n=20+20)
Change-Id: I5b907dbf52091e3de9710b09d67649c76f4c17e9
Reviewed-on: https://go-review.googlesource.com/20176
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Use only reflect.TypeOf to detect if argument is a string.
The wasString return is only needed in doPrint with the 'v' verb.
This type of string detection is handled correctly by reflect.TypeOf
which is used already in doPrint for identifying a string argument.
Remove now obsolete wasString computations and return values.
Change-Id: Iea2de7ac0f5c536a53eec63f7e679d628f5af8dc
Reviewed-on: https://go-review.googlesource.com/19976
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Named returned values should only be used on public funcs and methods
when it contributes to the documentation.
Named return values should not be used if they're only saving the
programmer a few lines of code inside the body of the function,
especially if that means there's stutter in the documentation or it
was only there so the programmer could use a naked return
statement. (Naked returns should not be used except in very small
functions)
This change is a manual audit & cleanup of public func signatures.
Signatures were not changed if:
* the func was private (wouldn't be in public godoc)
* the documentation referenced it
* the named return value was an interesting name. (i.e. it wasn't
simply stutter, repeating the name of the type)
There should be no changes in behavior. (At least: none intended)
Change-Id: I3472ef49619678fe786e5e0994bdf2d9de76d109
Reviewed-on: https://go-review.googlesource.com/20024
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>
Once upon a time fmt did use bytes.Buffer for its buffer.
The buffer write methods still mimic the bytes.Buffer signatures.
The current code depends on manipulating the buffer []bytes array directly
which makes going back to bytes.Buffer by only changing the type of buffer
impossible. Since type buffer is not exported the methods can be simplified
to the needs of fmt. This saves space and avoids unnecessary overhead.
Use WriteString instead of Write for known inputs since
WriteString is faster than Write to append the same data.
This also saves space in the binary.
Remove the add method from Printer and depending on the data to be written
use WriteRune or WriteByte directly instead.
In total makes the go binary around 4 kilobyte smaller.
name old time/op new time/op delta
SprintfEmpty-2 24.1ns ± 3% 23.8ns ± 1% -1.14% (p=0.000 n=20+20)
SprintfString-2 114ns ± 2% 114ns ± 4% ~ (p=0.558 n=20+19)
SprintfInt-2 116ns ± 9% 118ns ± 7% ~ (p=0.086 n=20+20)
SprintfIntInt-2 195ns ± 6% 193ns ± 5% ~ (p=0.345 n=20+19)
SprintfPrefixedInt-2 251ns ±16% 241ns ± 9% -3.69% (p=0.024 n=20+19)
SprintfFloat-2 203ns ± 4% 205ns ± 5% ~ (p=0.153 n=20+20)
SprintfBoolean-2 101ns ± 7% 96ns ±11% -5.23% (p=0.005 n=19+20)
ManyArgs-2 651ns ± 7% 628ns ± 7% -3.44% (p=0.002 n=20+20)
FprintInt-2 164ns ± 2% 158ns ± 2% -3.62% (p=0.000 n=20+18)
FprintfBytes-2 215ns ± 1% 216ns ± 1% +0.58% (p=0.000 n=20+20)
FprintIntNoAlloc-2 115ns ± 0% 112ns ± 0% -2.61% (p=0.000 n=20+20)
ScanInts-2 700µs ± 0% 702µs ± 1% +0.38% (p=0.000 n=18+20)
ScanRecursiveInt-2 82.7ms ± 0% 82.7ms ± 0% ~ (p=0.820 n=20+20)
Change-Id: I0409eb170b8a26d9f4eb271f6292e5d39faf2d8b
Reviewed-on: https://go-review.googlesource.com/19955
Reviewed-by: Rob Pike <r@golang.org>
Move the decision if zero padding is allowed to doPrintf
where the other formatting decisions are made.
Removes some dead code for negative f.wid that was never used
due to f.wid always being positive and f.minus deciding if left
or right padding should be used.
New padding code writes directly into the buffer and is as fast
as the old version but avoids the cost of needing package init.
name old time/op new time/op delta
SprintfPadding-2 246ns ± 5% 245ns ± 4% ~ (p=0.345 n=50+47)
Change-Id: I7dfddbac8e328f4ef0cdee8fafc0d06c784b2711
Reviewed-on: https://go-review.googlesource.com/19957
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
The construction
fmt.Printf("%*d", n, 4)
reads the argument n as a width specifier to use when printing 4.
Until now, only strict int type was accepted here and it couldn't
be fixed because the fix, using reflection, broke escape analysis
and added an extra allocation in every Printf call, even those that
do not use this feature.
The compiler has been fixed, although I am not sure when exactly,
so let's fix Printf and then write
Fixes#10732.
Change-Id: I79cf0c4fadd876265aa39d3cb62867247b36ab65
Reviewed-on: https://go-review.googlesource.com/14491
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Negative width arguments now left align the way a minus-width in the
format string aligns. The minus in the format string overrides the sign
of the argument as in C.
Precision behavior is modified to include an error if the argument is
negative. This differs from a negative precision in a format string
which just terminates the format.
Additional checks for large magnitude widths and precisions are added to
make the runtime behavior (failure, but with different error messages),
more consistent between format string specified width/precision and
argument specified width/precision.
Fixes#11376
Change-Id: I8c7ed21088e9c18128a45d4c487c5ab9fafd13ef
Reviewed-on: https://go-review.googlesource.com/11405
Reviewed-by: Rob Pike <r@golang.org>
Run-TryBot: Rob Pike <r@golang.org>
The old one was inferior.
Fixes#10695.
Change-Id: Ia7fb88c9ceb1b10197b77a54f729865385288d98
Reviewed-on: https://go-review.googlesource.com/9709
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
When a reflect.Value is passed to Printf (etc.), fmt called the
String method, which does not disclose its contents. To get the
contents, one could call Value.Interface(), but that is illegal
if the Value is not exported or otherwise forbidden.
This CL improves the situation with a trivial change to the
fmt package: when we see a reflect.Value as an argument,
we treat it exactly as we treat a reflect.Value we make inside
the package. This means that we always print the
contents of the Value as if _that_ was the argument to Printf.
This is arguably a breaking change but I think it is a genuine
improvement and no greater a break than many other tweaks
we have made to formatted output from this package.
Fixes#8965.
Change-Id: Ifc2a4ce3c1134ad5160e101d2196c22f1542faab
Reviewed-on: https://go-review.googlesource.com/8731
Reviewed-by: roger peppe <rogpeppe@gmail.com>
Reviewed-by: Russ Cox <rsc@golang.org>
It was inconsistent.
Also test these better.
Also document the default format for types.
This wasn't written down.
Fixes#8470.
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/154870043
Apply a similar transformation to %+v that we did to %#v, making it
a top-level setting separate from the + flag itself. This fixes the
appearance of flags in Formatters and cleans up the code too,
probably making it a little faster.
Fixes#8835.
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/154820043
The %#v verb is special: it says all values below need to print as %#v.
However, for some situations the # flag has other meanings and this
causes some issues, particularly in how Formatters work. Since %#v
dominates all formatting, translate it into actual state of the formatter
and decouple it from the # flag itself within the calculations (although
it must be restored when methods are doing the work.)
The result is cleaner code and correct handling of # for Formatters.
TODO: Apply the same thinking to the + flag in a followup CL.
Also, the wasString return value in handleMethods is always false,
so eliminate it.
Update #8835
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/146650043
This thing should never be called, but before
151960044 it was being called, incorrectly.
This is now just a precaution but let's pretend it
Fixes#8843
even though that was fixed by 151960044.
The test case was already there and ran, another mystery.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/151970043
