From 73df946d56c74384511a194dd01dbe099584fd1a Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 15:14:23 +0200 Subject: Adding upstream version 1.16.10. Signed-off-by: Daniel Baumann --- src/go/scanner/errors.go | 124 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 124 insertions(+) create mode 100644 src/go/scanner/errors.go (limited to 'src/go/scanner/errors.go') diff --git a/src/go/scanner/errors.go b/src/go/scanner/errors.go new file mode 100644 index 0000000..bf7bfa3 --- /dev/null +++ b/src/go/scanner/errors.go @@ -0,0 +1,124 @@ +// Copyright 2009 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 scanner + +import ( + "fmt" + "go/token" + "io" + "sort" +) + +// In an ErrorList, an error is represented by an *Error. +// The position Pos, if valid, points to the beginning of +// the offending token, and the error condition is described +// by Msg. +// +type Error struct { + Pos token.Position + Msg string +} + +// Error implements the error interface. +func (e Error) Error() string { + if e.Pos.Filename != "" || e.Pos.IsValid() { + // don't print "" + // TODO(gri) reconsider the semantics of Position.IsValid + return e.Pos.String() + ": " + e.Msg + } + return e.Msg +} + +// ErrorList is a list of *Errors. +// The zero value for an ErrorList is an empty ErrorList ready to use. +// +type ErrorList []*Error + +// Add adds an Error with given position and error message to an ErrorList. +func (p *ErrorList) Add(pos token.Position, msg string) { + *p = append(*p, &Error{pos, msg}) +} + +// Reset resets an ErrorList to no errors. +func (p *ErrorList) Reset() { *p = (*p)[0:0] } + +// ErrorList implements the sort Interface. +func (p ErrorList) Len() int { return len(p) } +func (p ErrorList) Swap(i, j int) { p[i], p[j] = p[j], p[i] } + +func (p ErrorList) Less(i, j int) bool { + e := &p[i].Pos + f := &p[j].Pos + // Note that it is not sufficient to simply compare file offsets because + // the offsets do not reflect modified line information (through //line + // comments). + if e.Filename != f.Filename { + return e.Filename < f.Filename + } + if e.Line != f.Line { + return e.Line < f.Line + } + if e.Column != f.Column { + return e.Column < f.Column + } + return p[i].Msg < p[j].Msg +} + +// Sort sorts an ErrorList. *Error entries are sorted by position, +// other errors are sorted by error message, and before any *Error +// entry. +// +func (p ErrorList) Sort() { + sort.Sort(p) +} + +// RemoveMultiples sorts an ErrorList and removes all but the first error per line. +func (p *ErrorList) RemoveMultiples() { + sort.Sort(p) + var last token.Position // initial last.Line is != any legal error line + i := 0 + for _, e := range *p { + if e.Pos.Filename != last.Filename || e.Pos.Line != last.Line { + last = e.Pos + (*p)[i] = e + i++ + } + } + (*p) = (*p)[0:i] +} + +// An ErrorList implements the error interface. +func (p ErrorList) Error() string { + switch len(p) { + case 0: + return "no errors" + case 1: + return p[0].Error() + } + return fmt.Sprintf("%s (and %d more errors)", p[0], len(p)-1) +} + +// Err returns an error equivalent to this error list. +// If the list is empty, Err returns nil. +func (p ErrorList) Err() error { + if len(p) == 0 { + return nil + } + return p +} + +// PrintError is a utility function that prints a list of errors to w, +// one error per line, if the err parameter is an ErrorList. Otherwise +// it prints the err string. +// +func PrintError(w io.Writer, err error) { + if list, ok := err.(ErrorList); ok { + for _, e := range list { + fmt.Fprintf(w, "%s\n", e) + } + } else if err != nil { + fmt.Fprintf(w, "%s\n", err) + } +} -- cgit v1.2.3