diff options
Diffstat (limited to 'vendor/golang.org/x/tools/go/ast')
| -rw-r--r-- | vendor/golang.org/x/tools/go/ast/astutil/enclosing.go | 627 | ||||
| -rw-r--r-- | vendor/golang.org/x/tools/go/ast/astutil/imports.go | 449 | ||||
| -rw-r--r-- | vendor/golang.org/x/tools/go/ast/astutil/util.go | 14 |
3 files changed, 1090 insertions, 0 deletions
diff --git a/vendor/golang.org/x/tools/go/ast/astutil/enclosing.go b/vendor/golang.org/x/tools/go/ast/astutil/enclosing.go new file mode 100644 index 000000000..6b7052b89 --- /dev/null +++ b/vendor/golang.org/x/tools/go/ast/astutil/enclosing.go @@ -0,0 +1,627 @@ +// Copyright 2013 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 astutil + +// This file defines utilities for working with source positions. + +import ( + "fmt" + "go/ast" + "go/token" + "sort" +) + +// PathEnclosingInterval returns the node that encloses the source +// interval [start, end), and all its ancestors up to the AST root. +// +// The definition of "enclosing" used by this function considers +// additional whitespace abutting a node to be enclosed by it. +// In this example: +// +// z := x + y // add them +// <-A-> +// <----B-----> +// +// the ast.BinaryExpr(+) node is considered to enclose interval B +// even though its [Pos()..End()) is actually only interval A. +// This behaviour makes user interfaces more tolerant of imperfect +// input. +// +// This function treats tokens as nodes, though they are not included +// in the result. e.g. PathEnclosingInterval("+") returns the +// enclosing ast.BinaryExpr("x + y"). +// +// If start==end, the 1-char interval following start is used instead. +// +// The 'exact' result is true if the interval contains only path[0] +// and perhaps some adjacent whitespace. It is false if the interval +// overlaps multiple children of path[0], or if it contains only +// interior whitespace of path[0]. +// In this example: +// +// z := x + y // add them +// <--C--> <---E--> +// ^ +// D +// +// intervals C, D and E are inexact. C is contained by the +// z-assignment statement, because it spans three of its children (:=, +// x, +). So too is the 1-char interval D, because it contains only +// interior whitespace of the assignment. E is considered interior +// whitespace of the BlockStmt containing the assignment. +// +// Precondition: [start, end) both lie within the same file as root. +// TODO(adonovan): return (nil, false) in this case and remove precond. +// Requires FileSet; see loader.tokenFileContainsPos. +// +// Postcondition: path is never nil; it always contains at least 'root'. +// +func PathEnclosingInterval(root *ast.File, start, end token.Pos) (path []ast.Node, exact bool) { + // fmt.Printf("EnclosingInterval %d %d\n", start, end) // debugging + + // Precondition: node.[Pos..End) and adjoining whitespace contain [start, end). + var visit func(node ast.Node) bool + visit = func(node ast.Node) bool { + path = append(path, node) + + nodePos := node.Pos() + nodeEnd := node.End() + + // fmt.Printf("visit(%T, %d, %d)\n", node, nodePos, nodeEnd) // debugging + + // Intersect [start, end) with interval of node. + if start < nodePos { + start = nodePos + } + if end > nodeEnd { + end = nodeEnd + } + + // Find sole child that contains [start, end). + children := childrenOf(node) + l := len(children) + for i, child := range children { + // [childPos, childEnd) is unaugmented interval of child. + childPos := child.Pos() + childEnd := child.End() + + // [augPos, augEnd) is whitespace-augmented interval of child. + augPos := childPos + augEnd := childEnd + if i > 0 { + augPos = children[i-1].End() // start of preceding whitespace + } + if i < l-1 { + nextChildPos := children[i+1].Pos() + // Does [start, end) lie between child and next child? + if start >= augEnd && end <= nextChildPos { + return false // inexact match + } + augEnd = nextChildPos // end of following whitespace + } + + // fmt.Printf("\tchild %d: [%d..%d)\tcontains interval [%d..%d)?\n", + // i, augPos, augEnd, start, end) // debugging + + // Does augmented child strictly contain [start, end)? + if augPos <= start && end <= augEnd { + _, isToken := child.(tokenNode) + return isToken || visit(child) + } + + // Does [start, end) overlap multiple children? + // i.e. left-augmented child contains start + // but LR-augmented child does not contain end. + if start < childEnd && end > augEnd { + break + } + } + + // No single child contained [start, end), + // so node is the result. Is it exact? + + // (It's tempting to put this condition before the + // child loop, but it gives the wrong result in the + // case where a node (e.g. ExprStmt) and its sole + // child have equal intervals.) + if start == nodePos && end == nodeEnd { + return true // exact match + } + + return false // inexact: overlaps multiple children + } + + if start > end { + start, end = end, start + } + + if start < root.End() && end > root.Pos() { + if start == end { + end = start + 1 // empty interval => interval of size 1 + } + exact = visit(root) + + // Reverse the path: + for i, l := 0, len(path); i < l/2; i++ { + path[i], path[l-1-i] = path[l-1-i], path[i] + } + } else { + // Selection lies within whitespace preceding the + // first (or following the last) declaration in the file. + // The result nonetheless always includes the ast.File. + path = append(path, root) + } + + return +} + +// tokenNode is a dummy implementation of ast.Node for a single token. +// They are used transiently by PathEnclosingInterval but never escape +// this package. +// +type tokenNode struct { + pos token.Pos + end token.Pos +} + +func (n tokenNode) Pos() token.Pos { + return n.pos +} + +func (n tokenNode) End() token.Pos { + return n.end +} + +func tok(pos token.Pos, len int) ast.Node { + return tokenNode{pos, pos + token.Pos(len)} +} + +// childrenOf returns the direct non-nil children of ast.Node n. +// It may include fake ast.Node implementations for bare tokens. +// it is not safe to call (e.g.) ast.Walk on such nodes. +// +func childrenOf(n ast.Node) []ast.Node { + var children []ast.Node + + // First add nodes for all true subtrees. + ast.Inspect(n, func(node ast.Node) bool { + if node == n { // push n + return true // recur + } + if node != nil { // push child + children = append(children, node) + } + return false // no recursion + }) + + // Then add fake Nodes for bare tokens. + switch n := n.(type) { + case *ast.ArrayType: + children = append(children, + tok(n.Lbrack, len("[")), + tok(n.Elt.End(), len("]"))) + + case *ast.AssignStmt: + children = append(children, + tok(n.TokPos, len(n.Tok.String()))) + + case *ast.BasicLit: + children = append(children, + tok(n.ValuePos, len(n.Value))) + + case *ast.BinaryExpr: + children = append(children, tok(n.OpPos, len(n.Op.String()))) + + case *ast.BlockStmt: + children = append(children, + tok(n.Lbrace, len("{")), + tok(n.Rbrace, len("}"))) + + case *ast.BranchStmt: + children = append(children, + tok(n.TokPos, len(n.Tok.String()))) + + case *ast.CallExpr: + children = append(children, + tok(n.Lparen, len("(")), + tok(n.Rparen, len(")"))) + if n.Ellipsis != 0 { + children = append(children, tok(n.Ellipsis, len("..."))) + } + + case *ast.CaseClause: + if n.List == nil { + children = append(children, + tok(n.Case, len("default"))) + } else { + children = append(children, + tok(n.Case, len("case"))) + } + children = append(children, tok(n.Colon, len(":"))) + + case *ast.ChanType: + switch n.Dir { + case ast.RECV: + children = append(children, tok(n.Begin, len("<-chan"))) + case ast.SEND: + children = append(children, tok(n.Begin, len("chan<-"))) + case ast.RECV | ast.SEND: + children = append(children, tok(n.Begin, len("chan"))) + } + + case *ast.CommClause: + if n.Comm == nil { + children = append(children, + tok(n.Case, len("default"))) + } else { + children = append(children, + tok(n.Case, len("case"))) + } + children = append(children, tok(n.Colon, len(":"))) + + case *ast.Comment: + // nop + + case *ast.CommentGroup: + // nop + + case *ast.CompositeLit: + children = append(children, + tok(n.Lbrace, len("{")), + tok(n.Rbrace, len("{"))) + + case *ast.DeclStmt: + // nop + + case *ast.DeferStmt: + children = append(children, + tok(n.Defer, len("defer"))) + + case *ast.Ellipsis: + children = append(children, + tok(n.Ellipsis, len("..."))) + + case *ast.EmptyStmt: + // nop + + case *ast.ExprStmt: + // nop + + case *ast.Field: + // TODO(adonovan): Field.{Doc,Comment,Tag}? + + case *ast.FieldList: + children = append(children, + tok(n.Opening, len("(")), + tok(n.Closing, len(")"))) + + case *ast.File: + // TODO test: Doc + children = append(children, + tok(n.Package, len("package"))) + + case *ast.ForStmt: + children = append(children, + tok(n.For, len("for"))) + + case *ast.FuncDecl: + // TODO(adonovan): FuncDecl.Comment? + + // Uniquely, FuncDecl breaks the invariant that + // preorder traversal yields tokens in lexical order: + // in fact, FuncDecl.Recv precedes FuncDecl.Type.Func. + // + // As a workaround, we inline the case for FuncType + // here and order things correctly. + // + children = nil // discard ast.Walk(FuncDecl) info subtrees + children = append(children, tok(n.Type.Func, len("func"))) + if n.Recv != nil { + children = append(children, n.Recv) + } + children = append(children, n.Name) + if n.Type.Params != nil { + children = append(children, n.Type.Params) + } + if n.Type.Results != nil { + children = append(children, n.Type.Results) + } + if n.Body != nil { + children = append(children, n.Body) + } + + case *ast.FuncLit: + // nop + + case *ast.FuncType: + if n.Func != 0 { + children = append(children, + tok(n.Func, len("func"))) + } + + case *ast.GenDecl: + children = append(children, + tok(n.TokPos, len(n.Tok.String()))) + if n.Lparen != 0 { + children = append(children, + tok(n.Lparen, len("(")), + tok(n.Rparen, len(")"))) + } + + case *ast.GoStmt: + children = append(children, + tok(n.Go, len("go"))) + + case *ast.Ident: + children = append(children, + tok(n.NamePos, len(n.Name))) + + case *ast.IfStmt: + children = append(children, + tok(n.If, len("if"))) + + case *ast.ImportSpec: + // TODO(adonovan): ImportSpec.{Doc,EndPos}? + + case *ast.IncDecStmt: + children = append(children, + tok(n.TokPos, len(n.Tok.String()))) + + case *ast.IndexExpr: + children = append(children, + tok(n.Lbrack, len("{")), + tok(n.Rbrack, len("}"))) + + case *ast.InterfaceType: + children = append(children, + tok(n.Interface, len("interface"))) + + case *ast.KeyValueExpr: + children = append(children, + tok(n.Colon, len(":"))) + + case *ast.LabeledStmt: + children = append(children, + tok(n.Colon, len(":"))) + + case *ast.MapType: + children = append(children, + tok(n.Map, len("map"))) + + case *ast.ParenExpr: + children = append(children, + tok(n.Lparen, len("(")), + tok(n.Rparen, len(")"))) + + case *ast.RangeStmt: + children = append(children, + tok(n.For, len("for")), + tok(n.TokPos, len(n.Tok.String()))) + + case *ast.ReturnStmt: + children = append(children, + tok(n.Return, len("return"))) + + case *ast.SelectStmt: + children = append(children, + tok(n.Select, len("select"))) + + case *ast.SelectorExpr: + // nop + + case *ast.SendStmt: + children = append(children, + tok(n.Arrow, len("<-"))) + + case *ast.SliceExpr: + children = append(children, + tok(n.Lbrack, len("[")), + tok(n.Rbrack, len("]"))) + + case *ast.StarExpr: + children = append(children, tok(n.Star, len("*"))) + + case *ast.StructType: + children = append(children, tok(n.Struct, len("struct"))) + + case *ast.SwitchStmt: + children = append(children, tok(n.Switch, len("switch"))) + + case *ast.TypeAssertExpr: + children = append(children, + tok(n.Lparen-1, len(".")), + tok(n.Lparen, len("(")), + tok(n.Rparen, len(")"))) + + case *ast.TypeSpec: + // TODO(adonovan): TypeSpec.{Doc,Comment}? + + case *ast.TypeSwitchStmt: + children = append(children, tok(n.Switch, len("switch"))) + + case *ast.UnaryExpr: + children = append(children, tok(n.OpPos, len(n.Op.String()))) + + case *ast.ValueSpec: + // TODO(adonovan): ValueSpec.{Doc,Comment}? + + case *ast.BadDecl, *ast.BadExpr, *ast.BadStmt: + // nop + } + + // TODO(adonovan): opt: merge the logic of ast.Inspect() into + // the switch above so we can make interleaved callbacks for + // both Nodes and Tokens in the right order and avoid the need + // to sort. + sort.Sort(byPos(children)) + + return children +} + +type byPos []ast.Node + +func (sl byPos) Len() int { + return len(sl) +} +func (sl byPos) Less(i, j int) bool { + return sl[i].Pos() < sl[j].Pos() +} +func (sl byPos) Swap(i, j int) { + sl[i], sl[j] = sl[j], sl[i] +} + +// NodeDescription returns a description of the concrete type of n suitable +// for a user interface. +// +// TODO(adonovan): in some cases (e.g. Field, FieldList, Ident, +// StarExpr) we could be much more specific given the path to the AST +// root. Perhaps we should do that. +// +func NodeDescription(n ast.Node) string { + switch n := n.(type) { + case *ast.ArrayType: + return "array type" + case *ast.AssignStmt: + return "assignment" + case *ast.BadDecl: + return "bad declaration" + case *ast.BadExpr: + return "bad expression" + case *ast.BadStmt: + return "bad statement" + case *ast.BasicLit: + return "basic literal" + case *ast.BinaryExpr: + return fmt.Sprintf("binary %s operation", n.Op) + case *ast.BlockStmt: + return "block" + case *ast.BranchStmt: + switch n.Tok { + case token.BREAK: + return "break statement" + case token.CONTINUE: + return "continue statement" + case token.GOTO: + return "goto statement" + case token.FALLTHROUGH: + return "fall-through statement" + } + case *ast.CallExpr: + if len(n.Args) == 1 && !n.Ellipsis.IsValid() { + return "function call (or conversion)" + } + return "function call" + case *ast.CaseClause: + return "case clause" + case *ast.ChanType: + return "channel type" + case *ast.CommClause: + return "communication clause" + case *ast.Comment: + return "comment" + case *ast.CommentGroup: + return "comment group" + case *ast.CompositeLit: + return "composite literal" + case *ast.DeclStmt: + return NodeDescription(n.Decl) + " statement" + case *ast.DeferStmt: + return "defer statement" + case *ast.Ellipsis: + return "ellipsis" + case *ast.EmptyStmt: + return "empty statement" + case *ast.ExprStmt: + return "expression statement" + case *ast.Field: + // Can be any of these: + // struct {x, y int} -- struct field(s) + // struct {T} -- anon struct field + // interface {I} -- interface embedding + // interface {f()} -- interface method + // func (A) func(B) C -- receiver, param(s), result(s) + return "field/method/parameter" + case *ast.FieldList: + return "field/method/parameter list" + case *ast.File: + return "source file" + case *ast.ForStmt: + return "for loop" + case *ast.FuncDecl: + return "function declaration" + case *ast.FuncLit: + return "function literal" + case *ast.FuncType: + return "function type" + case *ast.GenDecl: + switch n.Tok { + case token.IMPORT: + return "import declaration" + case token.CONST: + return "constant declaration" + case token.TYPE: + return "type declaration" + case token.VAR: + return "variable declaration" + } + case *ast.GoStmt: + return "go statement" + case *ast.Ident: + return "identifier" + case *ast.IfStmt: + return "if statement" + case *ast.ImportSpec: + return "import specification" + case *ast.IncDecStmt: + if n.Tok == token.INC { + return "increment statement" + } + return "decrement statement" + case *ast.IndexExpr: + return "index expression" + case *ast.InterfaceType: + return "interface type" + case *ast.KeyValueExpr: + return "key/value association" + case *ast.LabeledStmt: + return "statement label" + case *ast.MapType: + return "map type" + case *ast.Package: + return "package" + case *ast.ParenExpr: + return "parenthesized " + NodeDescription(n.X) + case *ast.RangeStmt: + return "range loop" + case *ast.ReturnStmt: + return "return statement" + case *ast.SelectStmt: + return "select statement" + case *ast.SelectorExpr: + return "selector" + case *ast.SendStmt: + return "channel send" + case *ast.SliceExpr: + return "slice expression" + case *ast.StarExpr: + return "*-operation" // load/store expr or pointer type + case *ast.StructType: + return "struct type" + case *ast.SwitchStmt: + return "switch statement" + case *ast.TypeAssertExpr: + return "type assertion" + case *ast.TypeSpec: + return "type specification" + case *ast.TypeSwitchStmt: + return "type switch" + case *ast.UnaryExpr: + return fmt.Sprintf("unary %s operation", n.Op) + case *ast.ValueSpec: + return "value specification" + + } + panic(fmt.Sprintf("unexpected node type: %T", n)) +} diff --git a/vendor/golang.org/x/tools/go/ast/astutil/imports.go b/vendor/golang.org/x/tools/go/ast/astutil/imports.go new file mode 100644 index 000000000..2e81f4d3a --- /dev/null +++ b/vendor/golang.org/x/tools/go/ast/astutil/imports.go @@ -0,0 +1,449 @@ +// Copyright 2013 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 astutil contains common utilities for working with the Go AST. +package astutil // import "golang.org/x/tools/go/ast/astutil" + +import ( + "fmt" + "go/ast" + "go/token" + "strconv" + "strings" +) + +// AddImport adds the import path to the file f, if absent. +func AddImport(fset *token.FileSet, f *ast.File, ipath string) (added bool) { + return AddNamedImport(fset, f, "", ipath) +} + +// AddNamedImport adds the import path to the file f, if absent. +// If name is not empty, it is used to rename the import. +// +// For example, calling +// AddNamedImport(fset, f, "pathpkg", "path") +// adds +// import pathpkg "path" +func AddNamedImport(fset *token.FileSet, f *ast.File, name, ipath string) (added bool) { + if imports(f, ipath) { + return false + } + + newImport := &ast.ImportSpec{ + Path: &ast.BasicLit{ + Kind: token.STRING, + Value: strconv.Quote(ipath), + }, + } + if name != "" { + newImport.Name = &ast.Ident{Name: name} + } + + // Find an import decl to add to. + // The goal is to find an existing import + // whose import path has the longest shared + // prefix with ipath. + var ( + bestMatch = -1 // length of longest shared prefix + lastImport = -1 // index in f.Decls of the file's final import decl + impDecl *ast.GenDecl // import decl containing the best match + impIndex = -1 // spec index in impDecl containing the best match + ) + for i, decl := range f.Decls { + gen, ok := decl.(*ast.GenDecl) + if ok && gen.Tok == token.IMPORT { + lastImport = i + // Do not add to import "C", to avoid disrupting the + // association with its doc comment, breaking cgo. + if declImports(gen, "C") { + continue + } + + // Match an empty import decl if that's all that is available. + if len(gen.Specs) == 0 && bestMatch == -1 { + impDecl = gen + } + + // Compute longest shared prefix with imports in this group. + for j, spec := range gen.Specs { + impspec := spec.(*ast.ImportSpec) + n := matchLen(importPath(impspec), ipath) + if n > bestMatch { + bestMatch = n + impDecl = gen + impIndex = j + } + } + } + } + + // If no import decl found, add one after the last import. + if impDecl == nil { + impDecl = &ast.GenDecl{ + Tok: token.IMPORT, + } + if lastImport >= 0 { + impDecl.TokPos = f.Decls[lastImport].End() + } else { + // There are no existing imports. + // Our new import goes after the package declaration and after + // the comment, if any, that starts on the same line as the + // package declaration. + impDecl.TokPos = f.Package + + file := fset.File(f.Package) + pkgLine := file.Line(f.Package) + for _, c := range f.Comments { + if file.Line(c.Pos()) > pkgLine { + break + } + impDecl.TokPos = c.End() + } + } + f.Decls = append(f.Decls, nil) + copy(f.Decls[lastImport+2:], f.Decls[lastImport+1:]) + f.Decls[lastImport+1] = impDecl + } + + // Insert new import at insertAt. + insertAt := 0 + if impIndex >= 0 { + // insert after the found import + insertAt = impIndex + 1 + } + impDecl.Specs = append(impDecl.Specs, nil) + copy(impDecl.Specs[insertAt+1:], impDecl.Specs[insertAt:]) + impDecl.Specs[insertAt] = newImport + pos := impDecl.Pos() + if insertAt > 0 { + // If there is a comment after an existing import, preserve the comment + // position by adding the new import after the comment. + if spec, ok := impDecl.Specs[insertAt-1].(*ast.ImportSpec); ok && spec.Comment != nil { + pos = spec.Comment.End() + } else { + // Assign same position as the previous import, + // so that the sorter sees it as being in the same block. + pos = impDecl.Specs[insertAt-1].Pos() + } + } + if newImport.Name != nil { + newImport.Name.NamePos = pos + } + newImport.Path.ValuePos = pos + newImport.EndPos = pos + + // Clean up parens. impDecl contains at least one spec. + if len(impDecl.Specs) == 1 { + // Remove unneeded parens. + impDecl.Lparen = token.NoPos + } else if !impDecl.Lparen.IsValid() { + // impDecl needs parens added. + impDecl.Lparen = impDecl.Specs[0].Pos() + } + + f.Imports = append(f.Imports, newImport) + + if len(f.Decls) <= 1 { + return true + } + + // Merge all the import declarations into the first one. + var first *ast.GenDecl + for i := 0; i < len(f.Decls); i++ { + decl := f.Decls[i] + gen, ok := decl.(*ast.GenDecl) + if !ok || gen.Tok != token.IMPORT || declImports(gen, "C") { + continue + } + if first == nil { + first = gen + continue // Don't touch the first one. + } + // We now know there is more than one package in this import + // declaration. Ensure that it ends up parenthesized. + first.Lparen = first.Pos() + // Move the imports of the other import declaration to the first one. + for _, spec := range gen.Specs { + spec.(*ast.ImportSpec).Path.ValuePos = first.Pos() + first.Specs = append(first.Specs, spec) + } + f.Decls = append(f.Decls[:i], f.Decls[i+1:]...) + i-- + } + + return true +} + +// DeleteImport deletes the import path from the file f, if present. +func DeleteImport(fset *token.FileSet, f *ast.File, path string) (deleted bool) { + return DeleteNamedImport(fset, f, "", path) +} + +// DeleteNamedImport deletes the import with the given name and path from the file f, if present. +func DeleteNamedImport(fset *token.FileSet, f *ast.File, name, path string) (deleted bool) { + var delspecs []*ast.ImportSpec + var delcomments []*ast.CommentGroup + + // Find the import nodes that import path, if any. + for i := 0; i < len(f.Decls); i++ { + decl := f.Decls[i] + gen, ok := decl.(*ast.GenDecl) + if !ok || gen.Tok != token.IMPORT { + continue + } + for j := 0; j < len(gen.Specs); j++ { + spec := gen.Specs[j] + impspec := spec.(*ast.ImportSpec) + if impspec.Name == nil && name != "" { + continue + } + if impspec.Name != nil && impspec.Name.Name != name { + continue + } + if importPath(impspec) != path { + continue + } + + // We found an import spec that imports path. + // Delete it. + delspecs = append(delspecs, impspec) + deleted = true + copy(gen.Specs[j:], gen.Specs[j+1:]) + gen.Specs = gen.Specs[:len(gen.Specs)-1] + + // If this was the last import spec in this decl, + // delete the decl, too. + if len(gen.Specs) == 0 { + copy(f.Decls[i:], f.Decls[i+1:]) + f.Decls = f.Decls[:len(f.Decls)-1] + i-- + break + } else if len(gen.Specs) == 1 { + if impspec.Doc != nil { + delcomments = append(delcomments, impspec.Doc) + } + if impspec.Comment != nil { + delcomments = append(delcomments, impspec.Comment) + } + for _, cg := range f.Comments { + // Found comment on the same line as the import spec. + if cg.End() < impspec.Pos() && fset.Position(cg.End()).Line == fset.Position(impspec.Pos()).Line { + delcomments = append(delcomments, cg) + break + } + } + + gen.Lparen = token.NoPos // drop parens + spec := gen.Specs[0].(*ast.ImportSpec) + if spec.Doc != nil { + // Move the documentation above the import statement. + gen.TokPos = spec.Doc.End() + 1 + } + + for _, cg := range f.Comments { + if cg.End() < spec.Pos() && fset.Position(cg.End()).Line == fset.Position(spec.Pos()).Line { + for fset.Position(gen.TokPos).Line != fset.Position(spec.Pos()).Line { + fset.File(gen.TokPos).MergeLine(fset.Position(gen.TokPos).Line) + } + break + } + } + } + if j > 0 { + lastImpspec := gen.Specs[j-1].(*ast.ImportSpec) + lastLine := fset.Position(lastImpspec.Path.ValuePos).Line + line := fset.Position(impspec.Path.ValuePos).Line + + // We deleted an entry but now there may be + // a blank line-sized hole where the import was. + if line-lastLine > 1 { + // There was a blank line immediately preceding the deleted import, + // so there's no need to close the hole. + // Do nothing. + } else { + // There was no blank line. Close the hole. + fset.File(gen.Rparen).MergeLine(line) + } + } + j-- + } + } + + // Delete imports from f.Imports. + for i := 0; i < len(f.Imports); i++ { + imp := f.Imports[i] + for j, del := range delspecs { + if imp == del { + copy(f.Imports[i:], f.Imports[i+1:]) + f.Imports = f.Imports[:len(f.Imports)-1] + copy(delspecs[j:], delspecs[j+1:]) + delspecs = delspecs[:len(delspecs)-1] + i-- + break + } + } + } + + // Delete comments from f.Comments. + for i := 0; i < len(f.Comments); i++ { + cg := f.Comments[i] + for j, del := range delcomments { + if cg == del { + copy(f.Comments[i:], f.Comments[i+1:]) + f.Comments = f.Comments[:len(f.Comments)-1] + copy(delcomments[j:], delcomments[j+1:]) + delcomments = delcomments[:len(delcomments)-1] + i-- + break + } + } + } + + if len(delspecs) > 0 { + panic(fmt.Sprintf("deleted specs from Decls but not Imports: %v", delspecs)) + } + + return +} + +// RewriteImport rewrites any import of path oldPath to path newPath. +func RewriteImport(fset *token.FileSet, f *ast.File, oldPath, newPath string) (rewrote bool) { + for _, imp := range f.Imports { + if importPath(imp) == oldPath { + rewrote = true + // record old End, because the default is to compute + // it using the length of imp.Path.Value. + imp.EndPos = imp.End() + imp.Path.Value = strconv.Quote(newPath) + } + } + return +} + +// UsesImport reports whether a given import is used. +func UsesImport(f *ast.File, path string) (used bool) { + spec := importSpec(f, path) + if spec == nil { + return + } + + name := spec.Name.String() + switch name { + case "<nil>": + // If the package name is not explicitly specified, + // make an educated guess. This is not guaranteed to be correct. + lastSlash := strings.LastIndex(path, "/") + if lastSlash == -1 { + name = path + } else { + name = path[lastSlash+1:] + } + case "_", ".": + // Not sure if this import is used - err on the side of caution. + return true + } + + ast.Walk(visitFn(func(n ast.Node) { + sel, ok := n.(*ast.SelectorExpr) + if ok && isTopName(sel.X, name) { + used = true + } + }), f) + + return +} + +type visitFn func(node ast.Node) + +func (fn visitFn) Visit(node ast.Node) ast.Visitor { + fn(node) + return fn +} + +// imports returns true if f imports path. +func imports(f *ast.File, path string) bool { + return importSpec(f, path) != nil +} + +// importSpec returns the import spec if f imports path, +// or nil otherwise. +func importSpec(f *ast.File, path string) *ast.ImportSpec { + for _, s := range f.Imports { + if importPath(s) == path { + return s + } + } + return nil +} + +// importPath returns the unquoted import path of s, +// or "" if the path is not properly quoted. +func importPath(s *ast.ImportSpec) string { + t, err := strconv.Unquote(s.Path.Value) + if err == nil { + return t + } + return "" +} + +// declImports reports whether gen contains an import of path. +func declImports(gen *ast.GenDecl, path string) bool { + if gen.Tok != token.IMPORT { + return false + } + for _, spec := range gen.Specs { + impspec := spec.(*ast.ImportSpec) + if importPath(impspec) == path { + return true + } + } + return false +} + +// matchLen returns the length of the longest path segment prefix shared by x and y. +func matchLen(x, y string) int { + n := 0 + for i := 0; i < len(x) && i < len(y) && x[i] == y[i]; i++ { + if x[i] == '/' { + n++ + } + } + return n +} + +// isTopName returns true if n is a top-level unresolved identifier with the given name. +func isTopName(n ast.Expr, name string) bool { + id, ok := n.(*ast.Ident) + return ok && id.Name == name && id.Obj == nil +} + +// Imports returns the file imports grouped by paragraph. +func Imports(fset *token.FileSet, f *ast.File) [][]*ast.ImportSpec { + var groups [][]*ast.ImportSpec + + for _, decl := range f.Decls { + genDecl, ok := decl.(*ast.GenDecl) + if !ok || genDecl.Tok != token.IMPORT { + break + } + + group := []*ast.ImportSpec{} + + var lastLine int + for _, spec := range genDecl.Specs { + importSpec := spec.(*ast.ImportSpec) + pos := importSpec.Path.ValuePos + line := fset.Position(pos).Line + if lastLine > 0 && pos > 0 && line-lastLine > 1 { + groups = append(groups, group) + group = []*ast.ImportSpec{} + } + group = append(group, importSpec) + lastLine = line + } + groups = append(groups, group) + } + + return groups +} diff --git a/vendor/golang.org/x/tools/go/ast/astutil/util.go b/vendor/golang.org/x/tools/go/ast/astutil/util.go new file mode 100644 index 000000000..763062982 --- /dev/null +++ b/vendor/golang.org/x/tools/go/ast/astutil/util.go @@ -0,0 +1,14 @@ +package astutil + +import "go/ast" + +// Unparen returns e with any enclosing parentheses stripped. +func Unparen(e ast.Expr) ast.Expr { + for { + p, ok := e.(*ast.ParenExpr) + if !ok { + return e + } + e = p.X + } +} |