blob: 5e191e45fbd69ab80839d6a01d921ebdcccfab01 [file] [log] [blame]
// Copyright 2020 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 source
import (
"bytes"
"go/ast"
"go/parser"
"go/token"
"go/types"
"testing"
)
func TestSearchForEnclosing(t *testing.T) {
tests := []struct {
desc string
// For convenience, consider the first occurrence of the identifier "X" in
// src.
src string
// By convention, "" means no type found.
wantTypeName string
}{
{
desc: "self enclosing",
src: `package a; type X struct {}`,
wantTypeName: "X",
},
{
// TODO(rFindley): is this correct, or do we want to resolve I2 here?
desc: "embedded interface in interface",
src: `package a; var y = i1.X; type i1 interface {I2}; type I2 interface{X()}`,
wantTypeName: "",
},
{
desc: "embedded interface in struct",
src: `package a; var y = t.X; type t struct {I}; type I interface{X()}`,
wantTypeName: "I",
},
{
desc: "double embedding",
src: `package a; var y = t1.X; type t1 struct {t2}; type t2 struct {I}; type I interface{X()}`,
wantTypeName: "I",
},
{
desc: "struct field",
src: `package a; type T struct { X int }`,
wantTypeName: "T",
},
{
desc: "nested struct field",
src: `package a; type T struct { E struct { X int } }`,
wantTypeName: "T",
},
{
desc: "slice entry",
src: `package a; type T []int; var S = T{X}; var X int = 2`,
wantTypeName: "T",
},
{
desc: "struct pointer literal",
src: `package a; type T struct {i int}; var L = &T{X}; const X = 2`,
wantTypeName: "T",
},
}
for _, test := range tests {
test := test
t.Run(test.desc, func(t *testing.T) {
fset := token.NewFileSet()
file, err := parser.ParseFile(fset, "a.go", test.src, parser.AllErrors)
if err != nil {
t.Fatal(err)
}
column := 1 + bytes.IndexRune([]byte(test.src), 'X')
pos := posAt(1, column, fset, "a.go")
path := pathEnclosingObjNode(file, pos)
if path == nil {
t.Fatalf("no ident found at (1, %d)", column)
}
info := newInfo()
if _, err = (*types.Config)(nil).Check("p", fset, []*ast.File{file}, info); err != nil {
t.Fatal(err)
}
typ := searchForEnclosing(info, path)
if typ == nil {
if test.wantTypeName != "" {
t.Errorf("searchForEnclosing(...) = <nil>, want %q", test.wantTypeName)
}
return
}
if got := typ.(*types.Named).Obj().Name(); got != test.wantTypeName {
t.Errorf("searchForEnclosing(...) = %q, want %q", got, test.wantTypeName)
}
})
}
}
// posAt returns the token.Pos corresponding to the 1-based (line, column)
// coordinates in the file fname of fset.
func posAt(line, column int, fset *token.FileSet, fname string) token.Pos {
var tok *token.File
fset.Iterate(func(f *token.File) bool {
if f.Name() == fname {
tok = f
return false
}
return true
})
if tok == nil {
return token.NoPos
}
start := tok.LineStart(line)
return start + token.Pos(column-1)
}
// newInfo returns a types.Info with all maps populated.
func newInfo() *types.Info {
return &types.Info{
Types: make(map[ast.Expr]types.TypeAndValue),
Defs: make(map[*ast.Ident]types.Object),
Uses: make(map[*ast.Ident]types.Object),
Implicits: make(map[ast.Node]types.Object),
Selections: make(map[*ast.SelectorExpr]*types.Selection),
Scopes: make(map[ast.Node]*types.Scope),
}
}