diff options
author | Thomas Voss <mail@thomasvoss.com> | 2024-08-07 00:21:12 +0200 |
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committer | Thomas Voss <mail@thomasvoss.com> | 2024-08-07 00:21:12 +0200 |
commit | 351c15d28e0444fd8a78c510a0c4d62ed433c758 (patch) | |
tree | b97aae6ec45c1b341075da147fb9e333246c19f7 /vendor/golang.org/x/text/internal/format |
Genesis commit
Diffstat (limited to 'vendor/golang.org/x/text/internal/format')
-rw-r--r-- | vendor/golang.org/x/text/internal/format/format.go | 41 | ||||
-rw-r--r-- | vendor/golang.org/x/text/internal/format/parser.go | 358 |
2 files changed, 399 insertions, 0 deletions
diff --git a/vendor/golang.org/x/text/internal/format/format.go b/vendor/golang.org/x/text/internal/format/format.go new file mode 100644 index 0000000..ee1c57a --- /dev/null +++ b/vendor/golang.org/x/text/internal/format/format.go @@ -0,0 +1,41 @@ +// Copyright 2015 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package format contains types for defining language-specific formatting of +// values. +// +// This package is internal now, but will eventually be exposed after the API +// settles. +package format // import "golang.org/x/text/internal/format" + +import ( + "fmt" + + "golang.org/x/text/language" +) + +// State represents the printer state passed to custom formatters. It provides +// access to the fmt.State interface and the sentence and language-related +// context. +type State interface { + fmt.State + + // Language reports the requested language in which to render a message. + Language() language.Tag + + // TODO: consider this and removing rune from the Format method in the + // Formatter interface. + // + // Verb returns the format variant to render, analogous to the types used + // in fmt. Use 'v' for the default or only variant. + // Verb() rune + + // TODO: more info: + // - sentence context such as linguistic features passed by the translator. +} + +// Formatter is analogous to fmt.Formatter. +type Formatter interface { + Format(state State, verb rune) +} diff --git a/vendor/golang.org/x/text/internal/format/parser.go b/vendor/golang.org/x/text/internal/format/parser.go new file mode 100644 index 0000000..855aed7 --- /dev/null +++ b/vendor/golang.org/x/text/internal/format/parser.go @@ -0,0 +1,358 @@ +// Copyright 2017 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package format + +import ( + "reflect" + "unicode/utf8" +) + +// A Parser parses a format string. The result from the parse are set in the +// struct fields. +type Parser struct { + Verb rune + + WidthPresent bool + PrecPresent bool + Minus bool + Plus bool + Sharp bool + Space bool + Zero bool + + // For the formats %+v %#v, we set the plusV/sharpV flags + // and clear the plus/sharp flags since %+v and %#v are in effect + // different, flagless formats set at the top level. + PlusV bool + SharpV bool + + HasIndex bool + + Width int + Prec int // precision + + // retain arguments across calls. + Args []interface{} + // retain current argument number across calls + ArgNum int + + // reordered records whether the format string used argument reordering. + Reordered bool + // goodArgNum records whether the most recent reordering directive was valid. + goodArgNum bool + + // position info + format string + startPos int + endPos int + Status Status +} + +// Reset initializes a parser to scan format strings for the given args. +func (p *Parser) Reset(args []interface{}) { + p.Args = args + p.ArgNum = 0 + p.startPos = 0 + p.Reordered = false +} + +// Text returns the part of the format string that was parsed by the last call +// to Scan. It returns the original substitution clause if the current scan +// parsed a substitution. +func (p *Parser) Text() string { return p.format[p.startPos:p.endPos] } + +// SetFormat sets a new format string to parse. It does not reset the argument +// count. +func (p *Parser) SetFormat(format string) { + p.format = format + p.startPos = 0 + p.endPos = 0 +} + +// Status indicates the result type of a call to Scan. +type Status int + +const ( + StatusText Status = iota + StatusSubstitution + StatusBadWidthSubstitution + StatusBadPrecSubstitution + StatusNoVerb + StatusBadArgNum + StatusMissingArg +) + +// ClearFlags reset the parser to default behavior. +func (p *Parser) ClearFlags() { + p.WidthPresent = false + p.PrecPresent = false + p.Minus = false + p.Plus = false + p.Sharp = false + p.Space = false + p.Zero = false + + p.PlusV = false + p.SharpV = false + + p.HasIndex = false +} + +// Scan scans the next part of the format string and sets the status to +// indicate whether it scanned a string literal, substitution or error. +func (p *Parser) Scan() bool { + p.Status = StatusText + format := p.format + end := len(format) + if p.endPos >= end { + return false + } + afterIndex := false // previous item in format was an index like [3]. + + p.startPos = p.endPos + p.goodArgNum = true + i := p.startPos + for i < end && format[i] != '%' { + i++ + } + if i > p.startPos { + p.endPos = i + return true + } + // Process one verb + i++ + + p.Status = StatusSubstitution + + // Do we have flags? + p.ClearFlags() + +simpleFormat: + for ; i < end; i++ { + c := p.format[i] + switch c { + case '#': + p.Sharp = true + case '0': + p.Zero = !p.Minus // Only allow zero padding to the left. + case '+': + p.Plus = true + case '-': + p.Minus = true + p.Zero = false // Do not pad with zeros to the right. + case ' ': + p.Space = true + default: + // Fast path for common case of ascii lower case simple verbs + // without precision or width or argument indices. + if 'a' <= c && c <= 'z' && p.ArgNum < len(p.Args) { + if c == 'v' { + // Go syntax + p.SharpV = p.Sharp + p.Sharp = false + // Struct-field syntax + p.PlusV = p.Plus + p.Plus = false + } + p.Verb = rune(c) + p.ArgNum++ + p.endPos = i + 1 + return true + } + // Format is more complex than simple flags and a verb or is malformed. + break simpleFormat + } + } + + // Do we have an explicit argument index? + i, afterIndex = p.updateArgNumber(format, i) + + // Do we have width? + if i < end && format[i] == '*' { + i++ + p.Width, p.WidthPresent = p.intFromArg() + + if !p.WidthPresent { + p.Status = StatusBadWidthSubstitution + } + + // We have a negative width, so take its value and ensure + // that the minus flag is set + if p.Width < 0 { + p.Width = -p.Width + p.Minus = true + p.Zero = false // Do not pad with zeros to the right. + } + afterIndex = false + } else { + p.Width, p.WidthPresent, i = parsenum(format, i, end) + if afterIndex && p.WidthPresent { // "%[3]2d" + p.goodArgNum = false + } + } + + // Do we have precision? + if i+1 < end && format[i] == '.' { + i++ + if afterIndex { // "%[3].2d" + p.goodArgNum = false + } + i, afterIndex = p.updateArgNumber(format, i) + if i < end && format[i] == '*' { + i++ + p.Prec, p.PrecPresent = p.intFromArg() + // Negative precision arguments don't make sense + if p.Prec < 0 { + p.Prec = 0 + p.PrecPresent = false + } + if !p.PrecPresent { + p.Status = StatusBadPrecSubstitution + } + afterIndex = false + } else { + p.Prec, p.PrecPresent, i = parsenum(format, i, end) + if !p.PrecPresent { + p.Prec = 0 + p.PrecPresent = true + } + } + } + + if !afterIndex { + i, afterIndex = p.updateArgNumber(format, i) + } + p.HasIndex = afterIndex + + if i >= end { + p.endPos = i + p.Status = StatusNoVerb + return true + } + + verb, w := utf8.DecodeRuneInString(format[i:]) + p.endPos = i + w + p.Verb = verb + + switch { + case verb == '%': // Percent does not absorb operands and ignores f.wid and f.prec. + p.startPos = p.endPos - 1 + p.Status = StatusText + case !p.goodArgNum: + p.Status = StatusBadArgNum + case p.ArgNum >= len(p.Args): // No argument left over to print for the current verb. + p.Status = StatusMissingArg + p.ArgNum++ + case verb == 'v': + // Go syntax + p.SharpV = p.Sharp + p.Sharp = false + // Struct-field syntax + p.PlusV = p.Plus + p.Plus = false + fallthrough + default: + p.ArgNum++ + } + return true +} + +// intFromArg gets the ArgNumth element of Args. On return, isInt reports +// whether the argument has integer type. +func (p *Parser) intFromArg() (num int, isInt bool) { + if p.ArgNum < len(p.Args) { + arg := p.Args[p.ArgNum] + num, isInt = arg.(int) // Almost always OK. + if !isInt { + // Work harder. + switch v := reflect.ValueOf(arg); v.Kind() { + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: + n := v.Int() + if int64(int(n)) == n { + num = int(n) + isInt = true + } + case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: + n := v.Uint() + if int64(n) >= 0 && uint64(int(n)) == n { + num = int(n) + isInt = true + } + default: + // Already 0, false. + } + } + p.ArgNum++ + if tooLarge(num) { + num = 0 + isInt = false + } + } + return +} + +// parseArgNumber returns the value of the bracketed number, minus 1 +// (explicit argument numbers are one-indexed but we want zero-indexed). +// The opening bracket is known to be present at format[0]. +// The returned values are the index, the number of bytes to consume +// up to the closing paren, if present, and whether the number parsed +// ok. The bytes to consume will be 1 if no closing paren is present. +func parseArgNumber(format string) (index int, wid int, ok bool) { + // There must be at least 3 bytes: [n]. + if len(format) < 3 { + return 0, 1, false + } + + // Find closing bracket. + for i := 1; i < len(format); i++ { + if format[i] == ']' { + width, ok, newi := parsenum(format, 1, i) + if !ok || newi != i { + return 0, i + 1, false + } + return width - 1, i + 1, true // arg numbers are one-indexed and skip paren. + } + } + return 0, 1, false +} + +// updateArgNumber returns the next argument to evaluate, which is either the value of the passed-in +// argNum or the value of the bracketed integer that begins format[i:]. It also returns +// the new value of i, that is, the index of the next byte of the format to process. +func (p *Parser) updateArgNumber(format string, i int) (newi int, found bool) { + if len(format) <= i || format[i] != '[' { + return i, false + } + p.Reordered = true + index, wid, ok := parseArgNumber(format[i:]) + if ok && 0 <= index && index < len(p.Args) { + p.ArgNum = index + return i + wid, true + } + p.goodArgNum = false + return i + wid, ok +} + +// 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++ { + if tooLarge(num) { + return 0, false, end // Overflow; crazy long number most likely. + } + num = num*10 + int(s[newi]-'0') + isnum = true + } + return +} |