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Diffstat (limited to 'src/pkg/go/ast/import.go')
-rw-r--r-- | src/pkg/go/ast/import.go | 196 |
1 files changed, 0 insertions, 196 deletions
diff --git a/src/pkg/go/ast/import.go b/src/pkg/go/ast/import.go deleted file mode 100644 index d2770d16c..000000000 --- a/src/pkg/go/ast/import.go +++ /dev/null @@ -1,196 +0,0 @@ -// Copyright 2011 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 ast - -import ( - "go/token" - "sort" - "strconv" -) - -// SortImports sorts runs of consecutive import lines in import blocks in f. -// It also removes duplicate imports when it is possible to do so without data loss. -func SortImports(fset *token.FileSet, f *File) { - for _, d := range f.Decls { - d, ok := d.(*GenDecl) - if !ok || d.Tok != token.IMPORT { - // Not an import declaration, so we're done. - // Imports are always first. - break - } - - if !d.Lparen.IsValid() { - // Not a block: sorted by default. - continue - } - - // Identify and sort runs of specs on successive lines. - i := 0 - specs := d.Specs[:0] - for j, s := range d.Specs { - if j > i && fset.Position(s.Pos()).Line > 1+fset.Position(d.Specs[j-1].End()).Line { - // j begins a new run. End this one. - specs = append(specs, sortSpecs(fset, f, d.Specs[i:j])...) - i = j - } - } - specs = append(specs, sortSpecs(fset, f, d.Specs[i:])...) - d.Specs = specs - - // Deduping can leave a blank line before the rparen; clean that up. - if len(d.Specs) > 0 { - lastSpec := d.Specs[len(d.Specs)-1] - lastLine := fset.Position(lastSpec.Pos()).Line - if rParenLine := fset.Position(d.Rparen).Line; rParenLine > lastLine+1 { - fset.File(d.Rparen).MergeLine(rParenLine - 1) - } - } - } -} - -func importPath(s Spec) string { - t, err := strconv.Unquote(s.(*ImportSpec).Path.Value) - if err == nil { - return t - } - return "" -} - -func importName(s Spec) string { - n := s.(*ImportSpec).Name - if n == nil { - return "" - } - return n.Name -} - -func importComment(s Spec) string { - c := s.(*ImportSpec).Comment - if c == nil { - return "" - } - return c.Text() -} - -// collapse indicates whether prev may be removed, leaving only next. -func collapse(prev, next Spec) bool { - if importPath(next) != importPath(prev) || importName(next) != importName(prev) { - return false - } - return prev.(*ImportSpec).Comment == nil -} - -type posSpan struct { - Start token.Pos - End token.Pos -} - -func sortSpecs(fset *token.FileSet, f *File, specs []Spec) []Spec { - // Can't short-circuit here even if specs are already sorted, - // since they might yet need deduplication. - // A lone import, however, may be safely ignored. - if len(specs) <= 1 { - return specs - } - - // Record positions for specs. - pos := make([]posSpan, len(specs)) - for i, s := range specs { - pos[i] = posSpan{s.Pos(), s.End()} - } - - // Identify comments in this range. - // Any comment from pos[0].Start to the final line counts. - lastLine := fset.Position(pos[len(pos)-1].End).Line - cstart := len(f.Comments) - cend := len(f.Comments) - for i, g := range f.Comments { - if g.Pos() < pos[0].Start { - continue - } - if i < cstart { - cstart = i - } - if fset.Position(g.End()).Line > lastLine { - cend = i - break - } - } - comments := f.Comments[cstart:cend] - - // Assign each comment to the import spec preceding it. - importComment := map[*ImportSpec][]*CommentGroup{} - specIndex := 0 - for _, g := range comments { - for specIndex+1 < len(specs) && pos[specIndex+1].Start <= g.Pos() { - specIndex++ - } - s := specs[specIndex].(*ImportSpec) - importComment[s] = append(importComment[s], g) - } - - // Sort the import specs by import path. - // Remove duplicates, when possible without data loss. - // Reassign the import paths to have the same position sequence. - // Reassign each comment to abut the end of its spec. - // Sort the comments by new position. - sort.Sort(byImportSpec(specs)) - - // Dedup. Thanks to our sorting, we can just consider - // adjacent pairs of imports. - deduped := specs[:0] - for i, s := range specs { - if i == len(specs)-1 || !collapse(s, specs[i+1]) { - deduped = append(deduped, s) - } else { - p := s.Pos() - fset.File(p).MergeLine(fset.Position(p).Line) - } - } - specs = deduped - - // Fix up comment positions - for i, s := range specs { - s := s.(*ImportSpec) - if s.Name != nil { - s.Name.NamePos = pos[i].Start - } - s.Path.ValuePos = pos[i].Start - s.EndPos = pos[i].End - for _, g := range importComment[s] { - for _, c := range g.List { - c.Slash = pos[i].End - } - } - } - - sort.Sort(byCommentPos(comments)) - - return specs -} - -type byImportSpec []Spec // slice of *ImportSpec - -func (x byImportSpec) Len() int { return len(x) } -func (x byImportSpec) Swap(i, j int) { x[i], x[j] = x[j], x[i] } -func (x byImportSpec) Less(i, j int) bool { - ipath := importPath(x[i]) - jpath := importPath(x[j]) - if ipath != jpath { - return ipath < jpath - } - iname := importName(x[i]) - jname := importName(x[j]) - if iname != jname { - return iname < jname - } - return importComment(x[i]) < importComment(x[j]) -} - -type byCommentPos []*CommentGroup - -func (x byCommentPos) Len() int { return len(x) } -func (x byCommentPos) Swap(i, j int) { x[i], x[j] = x[j], x[i] } -func (x byCommentPos) Less(i, j int) bool { return x[i].Pos() < x[j].Pos() } |