Пример #1
0
// findIdentifier looks for an identifier at byte-offset searchpos
// inside the parsed source represented by node.
// If it is part of a selector expression, it returns
// that expression rather than the identifier itself.
//
// As a special case, if it finds an import
// spec, it returns ImportSpec.
//
func findIdentifier(f *ast.File, searchpos int) ast.Node {
	ec := make(chan ast.Node)
	found := func(startPos, endPos token.Pos) bool {
		start := types.FileSet.Position(startPos).Offset
		end := start + int(endPos-startPos)
		return start <= searchpos && searchpos <= end
	}
	go func() {
		var visit func(ast.Node) bool
		visit = func(n ast.Node) bool {
			var startPos token.Pos
			switch n := n.(type) {
			default:
				return true
			case *ast.Ident:
				startPos = n.NamePos
			case *ast.SelectorExpr:
				startPos = n.Sel.NamePos
			case *ast.ImportSpec:
				startPos = n.Pos()
			case *ast.StructType:
				// If we find an anonymous bare field in a
				// struct type, its definition points to itself,
				// but we actually want to go elsewhere,
				// so assume (dubiously) that the expression
				// works globally and return a new node for it.
				for _, field := range n.Fields.List {
					if field.Names != nil {
						continue
					}
					t := field.Type
					if pt, ok := field.Type.(*ast.StarExpr); ok {
						t = pt.X
					}
					if id, ok := t.(*ast.Ident); ok {
						if found(id.NamePos, id.End()) {
							ec <- parseExpr(f.Scope, id.Name)
							runtime.Goexit()
						}
					}
				}
				return true
			}
			if found(startPos, n.End()) {
				ec <- n
				runtime.Goexit()
			}
			return true
		}
		ast.Walk(FVisitor(visit), f)
		ec <- nil
	}()
	ev := <-ec
	if ev == nil {
		fail("no identifier found")
	}
	return ev
}
Пример #2
0
// constainsNode returns true if x is found somewhere
// inside node.
func containsNode(node, x ast.Node) (found bool) {
	ast.Walk(funcVisitor(func(n ast.Node) bool {
		if !found {
			found = n == x
		}
		return !found
	}),
		node)
	return
}
Пример #3
0
func (v identVisitor) Visit(n ast.Node) ast.Visitor {
	switch n := n.(type) {
	case *ast.Ident:
		if strings.HasPrefix(n.Name, prefix) {
			v <- n
		}
		return nil
	case *ast.SelectorExpr:
		ast.Walk(v, n.X)
		if strings.HasPrefix(n.Sel.Name, prefix) {
			v <- n
		}
		return nil
	}
	return v
}
Пример #4
0
func TestOneFile(t *testing.T) {
	code, offsetMap := translateSymbols(testCode)
	//fmt.Printf("------------------- {%s}\n", code)
	f, err := parser.ParseFile(FileSet, "xx.go", code, 0, ast.NewScope(parser.Universe))
	if err != nil {
		t.Fatalf("parse failed: %v", err)
	}
	v := make(identVisitor)
	go func() {
		ast.Walk(v, f)
		close(v)
	}()
	for e := range v {
		testExpr(t, FileSet, e, offsetMap)
	}
}
Пример #5
0
// IterateSyms calls visitf for each identifier in the given file.  If
// visitf returns false, the iteration stops.  If visitf changes
// info.Ident.Name, the file is added to ctxt.ChangedFiles.
func (ctxt *Context) IterateSyms(f *ast.File, visitf func(info *Info) bool) {
	var visit astVisitor
	ok := true
	local := false // TODO set to true inside function body
	visit = func(n ast.Node) bool {
		if !ok {
			return false
		}
		switch n := n.(type) {
		case *ast.ImportSpec:
			// If the file imports a package to ".", abort
			// because we don't support that (yet).
			if n.Name != nil && n.Name.Name == "." {
				ctxt.logf(n.Pos(), "import to . not supported")
				ok = false
				return false
			}
			return true

		case *ast.FuncDecl:
			// add object for init functions
			if n.Recv == nil && n.Name.Name == "init" {
				n.Name.Obj = ast.NewObj(ast.Fun, "init")
			}
			if n.Recv != nil {
				ast.Walk(visit, n.Recv)
			}
			var e ast.Expr = n.Name
			if n.Recv != nil {
				// It's a method, so we need to synthesise a
				// selector expression so that visitExpr doesn't
				// just see a blank name.
				if len(n.Recv.List) != 1 {
					ctxt.logf(n.Pos(), "expected one receiver only!")
					return true
				}
				e = &ast.SelectorExpr{
					X:   n.Recv.List[0].Type,
					Sel: n.Name,
				}
			}
			ok = ctxt.visitExpr(f, e, false, visitf)
			local = true
			ast.Walk(visit, n.Type)
			if n.Body != nil {
				ast.Walk(visit, n.Body)
			}
			local = false
			return false

		case *ast.Ident:
			ok = ctxt.visitExpr(f, n, local, visitf)
			return false

		case *ast.KeyValueExpr:
			// don't try to resolve the key part of a key-value
			// because it might be a map key which doesn't
			// need resolving, and we can't tell without being
			// complicated with types.
			ast.Walk(visit, n.Value)
			return false

		case *ast.SelectorExpr:
			ast.Walk(visit, n.X)
			ok = ctxt.visitExpr(f, n, local, visitf)
			return false

		case *ast.File:
			for _, d := range n.Decls {
				ast.Walk(visit, d)
			}
			return false
		}

		return true
	}
	ast.Walk(visit, f)
}
Пример #6
0
func checkExprs(t *testing.T, pkg *ast.File, importer Importer) {
	var visit astVisitor
	stopped := false
	visit = func(n ast.Node) bool {
		if stopped {
			return false
		}
		mustResolve := false
		var e ast.Expr
		switch n := n.(type) {
		case *ast.ImportSpec:
			// If the file imports a package to ".", abort
			// because we don't support that (yet).
			if n.Name != nil && n.Name.Name == "." {
				stopped = true
				return false
			}
			return true

		case *ast.FuncDecl:
			// add object for init functions
			if n.Recv == nil && n.Name.Name == "init" {
				n.Name.Obj = ast.NewObj(ast.Fun, "init")
			}
			return true

		case *ast.Ident:
			if n.Name == "_" {
				return false
			}
			e = n
			mustResolve = true

		case *ast.KeyValueExpr:
			// don't try to resolve the key part of a key-value
			// because it might be a map key which doesn't
			// need resolving, and we can't tell without being
			// complicated with types.
			ast.Walk(visit, n.Value)
			return false

		case *ast.SelectorExpr:
			ast.Walk(visit, n.X)
			e = n
			mustResolve = true

		case *ast.File:
			for _, d := range n.Decls {
				ast.Walk(visit, d)
			}
			return false

		case ast.Expr:
			e = n

		default:
			return true
		}
		defer func() {
			if err := recover(); err != nil {
				t.Fatalf("panic (%v) on %T", err, e)
				//t.Fatalf("panic (%v) on %v at %v\n", err, e, FileSet.Position(e.Pos()))
			}
		}()
		obj, _ := ExprType(e, importer)
		if obj == nil && mustResolve {
			t.Errorf("no object for %v(%p, %T) at %v\n", e, e, e, FileSet.Position(e.Pos()))
		}
		return false
	}
	ast.Walk(visit, pkg)
}