package astutil
import "golang.org/x/tools/internal/astutil"
Package astutil provides various AST utility functions for gopls.
Index ¶
- func CloneNode[T ast.Node](n T) T
- func Comments(file *ast.File, start, end token.Pos) iter.Seq[*ast.Comment]
- func Deprecation(doc *ast.CommentGroup) string
- func DocComment(n ast.Node) *ast.CommentGroup
- func EnclosingFile(c inspector.Cursor) *ast.File
- func Equal(x, y ast.Node, identical func(x, y *ast.Ident) bool) bool
- func EqualSyntax(x, y ast.Expr) bool
- func FlatFields(list *ast.FieldList) iter.Seq2[*ast.Ident, *ast.Field]
- func Format(fset *token.FileSet, n ast.Node) string
- func IsChildOf(cur inspector.Cursor, ek edge.Kind) bool
- func NodeContains(n ast.Node, pos token.Pos) bool
- func PosInStringLiteral(lit *ast.BasicLit, offset int) (token.Pos, error)
- func PreorderStack(root ast.Node, stack []ast.Node, f func(n ast.Node, stack []ast.Node) bool)
- func PurgeFuncBodies(src []byte) []byte
- func RangeInStringLiteral(lit *ast.BasicLit, start, end int) (token.Pos, token.Pos, error)
- func UnpackRecv(rtyp ast.Expr) (ptr bool, rname *ast.Ident, tparams []*ast.Ident)
- type Directive
Functions ¶
func CloneNode ¶
CloneNode returns a deep copy of a Node. It omits pointers to ast.{Scope,Object} variables.
func Comments ¶
Comments returns an iterator over the comments overlapping the specified interval.
func Deprecation ¶
func Deprecation(doc *ast.CommentGroup) string
Deprecation returns the paragraph of the doc comment that starts with the conventional "Deprecation: " marker, as defined by https://go.dev/wiki/Deprecated, or "" if the documented symbol is not deprecated.
func DocComment ¶
func DocComment(n ast.Node) *ast.CommentGroup
DocComment returns the doc comment for a node, if any.
func EnclosingFile ¶
EnclosingFile returns the syntax tree for the file enclosing c.
TODO(adonovan): promote this to a method of Cursor.
func Equal ¶
Equal reports whether two nodes are structurally equal, ignoring fields of type token.Pos, ast.Object, and ast.Scope, and comments.
The operands x and y may be nil. A nil slice is not equal to an empty slice.
The provided function determines whether two identifiers should be considered identical.
func EqualSyntax ¶
EqualSyntax reports whether x and y are equal. Identifiers are considered equal if they are spelled the same. Comments are ignored.
func FlatFields ¶
FlatFields 'flattens' an ast.FieldList, returning an iterator over each (name, field) combination in the list. For unnamed fields, the identifier is nil.
func Format ¶
Format returns a string representation of the node n.
func IsChildOf ¶
IsChildOf reports whether cur.ParentEdge is ek.
TODO(adonovan): promote to a method of Cursor.
func NodeContains ¶
NodeContains reports whether the Pos/End range of node n encloses the given position pos.
It is inclusive of both end points, to allow hovering (etc) when the cursor is immediately after a node.
For unfortunate historical reasons, the Pos/End extent of an ast.File runs from the start of its package declaration---excluding copyright comments, build tags, and package documentation---to the end of its last declaration, excluding any trailing comments. So, as a special case, if n is an ast.File, NodeContains uses n.FileStart <= pos && pos <= n.FileEnd to report whether the position lies anywhere within the file.
Precondition: n must not be nil.
func PosInStringLiteral ¶
PosInStringLiteral returns the position within a string literal corresponding to the specified byte offset within the logical string that it denotes.
func PreorderStack ¶
PreorderStack traverses the tree rooted at root, calling f before visiting each node.
Each call to f provides the current node and traversal stack, consisting of the original value of stack appended with all nodes from root to n, excluding n itself. (This design allows calls to PreorderStack to be nested without double counting.)
If f returns false, the traversal skips over that subtree. Unlike ast.Inspect, no second call to f is made after visiting node n. In practice, the second call is nearly always used only to pop the stack, and it is surprisingly tricky to do this correctly; see https://go.dev/issue/73319.
TODO(adonovan): replace with ast.PreorderStack when go1.25 is assured.
func PurgeFuncBodies ¶
PurgeFuncBodies returns a copy of src in which the contents of each outermost {...} region except struct and interface types have been deleted. This reduces the amount of work required to parse the top-level declarations.
PurgeFuncBodies does not preserve newlines or position information. Also, if the input is invalid, parsing the output of PurgeFuncBodies may result in a different tree due to its effects on parser error recovery.
func RangeInStringLiteral ¶
RangeInStringLiteral calculates the positional range within a string literal corresponding to the specified start and end byte offsets within the logical string.
func UnpackRecv ¶
UnpackRecv unpacks a receiver type expression, reporting whether it is a pointer receiver, along with the type name identifier and any receiver type parameter identifiers.
Copied (with modifications) from go/types.
Types ¶
type Directive ¶
type Directive struct {
Pos token.Pos // of preceding "//"
Tool string
Name string
Args string // may contain internal spaces
}
A directive is a comment line with special meaning to the Go toolchain or another tool. It has the form:
//tool:name args
The "tool:" portion is missing for the three directives named line, extern, and export.
See https://go.dev/doc/comment#Syntax for details of Go comment syntax and https://pkg.go.dev/cmd/compile#hdr-Compiler_Directives for details of directives used by the Go compiler.
func Directives ¶
func Directives(g *ast.CommentGroup) (res []*Directive)
Directives returns the directives within the comment.
Source Files ¶
clone.go comment.go equal.go fields.go purge.go stringlit.go unpack.go util.go
- Version
- v0.38.0
- Published
- Oct 8, 2025
- Platform
- windows/amd64
- Imports
- 15 packages
- Last checked
- 8 minutes ago –
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