diff options
Diffstat (limited to 'vendor/github.com/uptrace/bun/internal/parser/parser.go')
-rw-r--r-- | vendor/github.com/uptrace/bun/internal/parser/parser.go | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/vendor/github.com/uptrace/bun/internal/parser/parser.go b/vendor/github.com/uptrace/bun/internal/parser/parser.go new file mode 100644 index 000000000..cdfc0be16 --- /dev/null +++ b/vendor/github.com/uptrace/bun/internal/parser/parser.go @@ -0,0 +1,141 @@ +package parser + +import ( + "bytes" + "strconv" + + "github.com/uptrace/bun/internal" +) + +type Parser struct { + b []byte + i int +} + +func New(b []byte) *Parser { + return &Parser{ + b: b, + } +} + +func NewString(s string) *Parser { + return New(internal.Bytes(s)) +} + +func (p *Parser) Valid() bool { + return p.i < len(p.b) +} + +func (p *Parser) Bytes() []byte { + return p.b[p.i:] +} + +func (p *Parser) Read() byte { + if p.Valid() { + c := p.b[p.i] + p.Advance() + return c + } + return 0 +} + +func (p *Parser) Peek() byte { + if p.Valid() { + return p.b[p.i] + } + return 0 +} + +func (p *Parser) Advance() { + p.i++ +} + +func (p *Parser) Skip(skip byte) bool { + if p.Peek() == skip { + p.Advance() + return true + } + return false +} + +func (p *Parser) SkipBytes(skip []byte) bool { + if len(skip) > len(p.b[p.i:]) { + return false + } + if !bytes.Equal(p.b[p.i:p.i+len(skip)], skip) { + return false + } + p.i += len(skip) + return true +} + +func (p *Parser) ReadSep(sep byte) ([]byte, bool) { + ind := bytes.IndexByte(p.b[p.i:], sep) + if ind == -1 { + b := p.b[p.i:] + p.i = len(p.b) + return b, false + } + + b := p.b[p.i : p.i+ind] + p.i += ind + 1 + return b, true +} + +func (p *Parser) ReadIdentifier() (string, bool) { + if p.i < len(p.b) && p.b[p.i] == '(' { + s := p.i + 1 + if ind := bytes.IndexByte(p.b[s:], ')'); ind != -1 { + b := p.b[s : s+ind] + p.i = s + ind + 1 + return internal.String(b), false + } + } + + ind := len(p.b) - p.i + var alpha bool + for i, c := range p.b[p.i:] { + if isNum(c) { + continue + } + if isAlpha(c) || (i > 0 && alpha && c == '_') { + alpha = true + continue + } + ind = i + break + } + if ind == 0 { + return "", false + } + b := p.b[p.i : p.i+ind] + p.i += ind + return internal.String(b), !alpha +} + +func (p *Parser) ReadNumber() int { + ind := len(p.b) - p.i + for i, c := range p.b[p.i:] { + if !isNum(c) { + ind = i + break + } + } + if ind == 0 { + return 0 + } + n, err := strconv.Atoi(string(p.b[p.i : p.i+ind])) + if err != nil { + panic(err) + } + p.i += ind + return n +} + +func isNum(c byte) bool { + return c >= '0' && c <= '9' +} + +func isAlpha(c byte) bool { + return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') +} |