+++ /dev/null
-package source
-
-import (
- "context"
- "go/ast"
- "go/token"
- "sort"
-
- "golang.org/x/tools/internal/lsp/protocol"
-)
-
-// FoldingRangeInfo holds range and kind info of folding for an ast.Node
-type FoldingRangeInfo struct {
- MappedRange
- Kind protocol.FoldingRangeKind
-}
-
-// FoldingRange gets all of the folding range for f.
-func FoldingRange(ctx context.Context, snapshot Snapshot, fh FileHandle, lineFoldingOnly bool) (ranges []*FoldingRangeInfo, err error) {
- // TODO(suzmue): consider limiting the number of folding ranges returned, and
- // implement a way to prioritize folding ranges in that case.
- pgf, err := snapshot.ParseGo(ctx, fh, ParseFull)
- if err != nil {
- return nil, err
- }
- fset := snapshot.FileSet()
-
- // Get folding ranges for comments separately as they are not walked by ast.Inspect.
- ranges = append(ranges, commentsFoldingRange(fset, pgf.Mapper, pgf.File)...)
-
- visit := func(n ast.Node) bool {
- rng := foldingRangeFunc(fset, pgf.Mapper, n, lineFoldingOnly)
- if rng != nil {
- ranges = append(ranges, rng)
- }
- return true
- }
- // Walk the ast and collect folding ranges.
- ast.Inspect(pgf.File, visit)
-
- sort.Slice(ranges, func(i, j int) bool {
- irng, _ := ranges[i].Range()
- jrng, _ := ranges[j].Range()
- return protocol.CompareRange(irng, jrng) < 0
- })
-
- return ranges, nil
-}
-
-// foldingRangeFunc calculates the line folding range for ast.Node n
-func foldingRangeFunc(fset *token.FileSet, m *protocol.ColumnMapper, n ast.Node, lineFoldingOnly bool) *FoldingRangeInfo {
- // TODO(suzmue): include trailing empty lines before the closing
- // parenthesis/brace.
- var kind protocol.FoldingRangeKind
- var start, end token.Pos
- switch n := n.(type) {
- case *ast.BlockStmt:
- // Fold between positions of or lines between "{" and "}".
- var startList, endList token.Pos
- if num := len(n.List); num != 0 {
- startList, endList = n.List[0].Pos(), n.List[num-1].End()
- }
- start, end = validLineFoldingRange(fset, n.Lbrace, n.Rbrace, startList, endList, lineFoldingOnly)
- case *ast.CaseClause:
- // Fold from position of ":" to end.
- start, end = n.Colon+1, n.End()
- case *ast.CommClause:
- // Fold from position of ":" to end.
- start, end = n.Colon+1, n.End()
- case *ast.CallExpr:
- // Fold from position of "(" to position of ")".
- start, end = n.Lparen+1, n.Rparen
- case *ast.FieldList:
- // Fold between positions of or lines between opening parenthesis/brace and closing parenthesis/brace.
- var startList, endList token.Pos
- if num := len(n.List); num != 0 {
- startList, endList = n.List[0].Pos(), n.List[num-1].End()
- }
- start, end = validLineFoldingRange(fset, n.Opening, n.Closing, startList, endList, lineFoldingOnly)
- case *ast.GenDecl:
- // If this is an import declaration, set the kind to be protocol.Imports.
- if n.Tok == token.IMPORT {
- kind = protocol.Imports
- }
- // Fold between positions of or lines between "(" and ")".
- var startSpecs, endSpecs token.Pos
- if num := len(n.Specs); num != 0 {
- startSpecs, endSpecs = n.Specs[0].Pos(), n.Specs[num-1].End()
- }
- start, end = validLineFoldingRange(fset, n.Lparen, n.Rparen, startSpecs, endSpecs, lineFoldingOnly)
- case *ast.CompositeLit:
- // Fold between positions of or lines between "{" and "}".
- var startElts, endElts token.Pos
- if num := len(n.Elts); num != 0 {
- startElts, endElts = n.Elts[0].Pos(), n.Elts[num-1].End()
- }
- start, end = validLineFoldingRange(fset, n.Lbrace, n.Rbrace, startElts, endElts, lineFoldingOnly)
- }
-
- // Check that folding positions are valid.
- if !start.IsValid() || !end.IsValid() {
- return nil
- }
- // in line folding mode, do not fold if the start and end lines are the same.
- if lineFoldingOnly && fset.Position(start).Line == fset.Position(end).Line {
- return nil
- }
- return &FoldingRangeInfo{
- MappedRange: NewMappedRange(fset, m, start, end),
- Kind: kind,
- }
-}
-
-// validLineFoldingRange returns start and end token.Pos for folding range if the range is valid.
-// returns token.NoPos otherwise, which fails token.IsValid check
-func validLineFoldingRange(fset *token.FileSet, open, close, start, end token.Pos, lineFoldingOnly bool) (token.Pos, token.Pos) {
- if lineFoldingOnly {
- if !open.IsValid() || !close.IsValid() {
- return token.NoPos, token.NoPos
- }
-
- // Don't want to fold if the start/end is on the same line as the open/close
- // as an example, the example below should *not* fold:
- // var x = [2]string{"d",
- // "e" }
- if fset.Position(open).Line == fset.Position(start).Line ||
- fset.Position(close).Line == fset.Position(end).Line {
- return token.NoPos, token.NoPos
- }
-
- return open + 1, end
- }
- return open + 1, close
-}
-
-// commentsFoldingRange returns the folding ranges for all comment blocks in file.
-// The folding range starts at the end of the first comment, and ends at the end of the
-// comment block and has kind protocol.Comment.
-func commentsFoldingRange(fset *token.FileSet, m *protocol.ColumnMapper, file *ast.File) (comments []*FoldingRangeInfo) {
- for _, commentGrp := range file.Comments {
- // Don't fold single comments.
- if len(commentGrp.List) <= 1 {
- continue
- }
- comments = append(comments, &FoldingRangeInfo{
- // Fold from the end of the first line comment to the end of the comment block.
- MappedRange: NewMappedRange(fset, m, commentGrp.List[0].End(), commentGrp.End()),
- Kind: protocol.Comment,
- })
- }
- return comments
-}
projects / dotfiles / .git / blobdiff