Exemplo n.º 1
0
func (g *goGen) genFunc(o *types.Func) {
	g.Printf("func proxy_%s(out, in *seq.Buffer) {\n", o.Name())
	g.Indent()
	g.genFuncBody(o, g.pkg.Name())
	g.Outdent()
	g.Printf("}\n\n")
}
Exemplo n.º 2
0
// interfaceMethod returns a function and receiver pointer for the specified
// interface and method pair.
func (fr *frame) interfaceMethod(lliface llvm.Value, ifacety types.Type, method *types.Func) (fn, recv *govalue) {
	llitab := fr.builder.CreateExtractValue(lliface, 0, "")
	recv = newValue(fr.builder.CreateExtractValue(lliface, 1, ""), types.Typ[types.UnsafePointer])
	methodset := fr.types.MethodSet(ifacety)
	// TODO(axw) cache ordered method index
	index := -1
	for i, m := range orderedMethodSet(methodset) {
		if m.Obj() == method {
			index = i
			break
		}
	}
	if index == -1 {
		panic("could not find method index")
	}
	llitab = fr.builder.CreateBitCast(llitab, llvm.PointerType(llvm.PointerType(llvm.Int8Type(), 0), 0), "")
	// Skip runtime type pointer.
	llifnptr := fr.builder.CreateGEP(llitab, []llvm.Value{
		llvm.ConstInt(llvm.Int32Type(), uint64(index+1), false),
	}, "")

	llifn := fr.builder.CreateLoad(llifnptr, "")
	// Replace receiver type with unsafe.Pointer.
	recvparam := types.NewParam(0, nil, "", types.Typ[types.UnsafePointer])
	sig := method.Type().(*types.Signature)
	sig = types.NewSignature(nil, recvparam, sig.Params(), sig.Results(), sig.Variadic())
	fn = newValue(llifn, sig)
	return
}
Exemplo n.º 3
0
func (g *goGen) genFuncBody(o *types.Func, selectorLHS string) {
	sig := o.Type().(*types.Signature)
	params := sig.Params()
	for i := 0; i < params.Len(); i++ {
		p := params.At(i)
		t := seqType(p.Type())
		if t == "Ref" {
			name := p.Type().(*types.Named).Obj().Name()
			g.Printf("var param_%s %s.%s\n", p.Name(), g.pkg.Name(), name)
			g.Printf("param_%s_ref := in.ReadRef()\n", p.Name())
			g.Printf("if param_%s_ref.Num < 0 {\n", p.Name())
			g.Printf("    param_%s = param_%s_ref.Get().(%s.%s)\n", p.Name(), p.Name(), g.pkg.Name(), name)
			g.Printf("} else {\n")
			g.Printf("    param_%s = (*proxy%s)(param_%s_ref)\n", p.Name(), name, p.Name())
			g.Printf("}\n")
		} else {
			g.Printf("param_%s := in.Read%s()\n", p.Name(), t)
		}
	}

	res := sig.Results()
	if res.Len() > 2 || res.Len() == 2 && !isErrorType(res.At(1).Type()) {
		g.errorf("functions and methods must return either zero or one values, and optionally an error")
		return
	}
	returnsValue := false
	returnsError := false
	if res.Len() == 1 {
		if isErrorType(res.At(0).Type()) {
			returnsError = true
			g.Printf("err := ")
		} else {
			returnsValue = true
			g.Printf("res := ")
		}
	} else if res.Len() == 2 {
		returnsValue = true
		returnsError = true
		g.Printf("res, err := ")
	}

	g.Printf("%s.%s(", selectorLHS, o.Name())
	for i := 0; i < params.Len(); i++ {
		if i > 0 {
			g.Printf(", ")
		}
		g.Printf("param_%s", params.At(i).Name())
	}
	g.Printf(")\n")

	if returnsValue {
		g.genWrite("res", "out", res.At(0).Type())
	}
	if returnsError {
		g.genWrite("err", "out", res.At(res.Len()-1).Type())
	}
}
Exemplo n.º 4
0
func (p *printer) printFunc(recvType types.Type, obj *types.Func) {
	p.print("func ")
	sig := obj.Type().(*types.Signature)
	if recvType != nil {
		p.print("(")
		p.writeType(p.pkg, recvType)
		p.print(") ")
	}
	p.print(obj.Name())
	p.writeSignature(p.pkg, sig)
}
Exemplo n.º 5
0
func (g *javaGen) genFunc(o *types.Func, method bool) {
	if err := g.funcSignature(o, !method); err != nil {
		g.errorf("%v", err)
		return
	}
	sig := o.Type().(*types.Signature)
	res := sig.Results()

	g.Printf(" {\n")
	g.Indent()
	g.Printf("go.Seq _in = new go.Seq();\n")
	g.Printf("go.Seq _out = new go.Seq();\n")

	returnsError := false
	var resultType types.Type
	if res.Len() > 0 {
		if !isErrorType(res.At(0).Type()) {
			resultType = res.At(0).Type()
		}
		if res.Len() > 1 || isErrorType(res.At(0).Type()) {
			returnsError = true
		}
	}
	if resultType != nil {
		t := g.javaType(resultType)
		g.Printf("%s _result;\n", t)
	}

	if method {
		g.Printf("_in.writeRef(ref);\n")
	}
	params := sig.Params()
	for i := 0; i < params.Len(); i++ {
		p := params.At(i)
		g.Printf("_in.write%s;\n", seqWrite(p.Type(), paramName(params, i)))
	}
	g.Printf("Seq.send(DESCRIPTOR, CALL_%s, _in, _out);\n", o.Name())
	if resultType != nil {
		g.genRead("_result", "_out", resultType)
	}
	if returnsError {
		g.Printf(`String _err = _out.readString();
if (_err != null) {
    throw new Exception(_err);
}
`)
	}
	if resultType != nil {
		g.Printf("return _result;\n")
	}
	g.Outdent()
	g.Printf("}\n\n")
}
Exemplo n.º 6
0
// check if function is a test function for the testing package
// we don't unexport those
func (e *Export) checkFunction(from *types.Func, to string) {
	if !strings.HasPrefix(from.Name(), "Test") {
		return
	}
	sig := from.Type().(*types.Signature)
	if sig.Params().Len() != 1 {
		return
	}
	if sig.Params().At(0).Type().String() == "*testing.T" {
		e.Conflicting = true
		return
	}
}
Exemplo n.º 7
0
func (g *goGen) genFuncBody(o *types.Func) {

	sig := o.Type().(*types.Signature)
	results := newVars(sig.Results())
	for i := range results {
		if i > 0 {
			g.Printf(", ")
		}
		g.Printf("_gopy_%03d", i)
	}
	if len(results) > 0 {
		g.Printf(" := ")
	}

	g.Printf("%s.%s(", g.pkg.Name(), o.Name())

	args := sig.Params()
	for i := 0; i < args.Len(); i++ {
		arg := args.At(i)
		tail := ""
		if i+1 < args.Len() {
			tail = ", "
		}
		g.Printf("%s%s", arg.Name(), tail)
	}
	g.Printf(")\n")

	if len(results) <= 0 {
		return
	}

	g.Printf("return ")
	for i, res := range results {
		if i > 0 {
			g.Printf(", ")
		}
		// if needWrap(res.GoType()) {
		// 	g.Printf("")
		// }
		if res.needWrap() {
			g.Printf("%s(unsafe.Pointer(&", res.dtype.cgotype)
		}
		g.Printf("_gopy_%03d /* %#v %v */", i, res, res.GoType().Underlying())
		if res.needWrap() {
			g.Printf("))")
		}
	}
	g.Printf("\n")
}
Exemplo n.º 8
0
func (g *cpyGen) genFunc(o *types.Func) {

	g.impl.Printf(`
/* pythonization of: %[2]s.%[1]s */
static PyObject*
gopy_%[1]s(PyObject *self, PyObject *args) {
`,
		o.Name(), g.pkg.pkg.Name(),
	)

	g.impl.Indent()
	g.genFuncBody(o)
	g.impl.Outdent()
	g.impl.Printf("}\n\n")
}
Exemplo n.º 9
0
// lookupMethod returns the method set for type typ, which may be one
// of the interpreter's fake types.
func lookupMethod(i *interpreter, typ types.Type, meth *types.Func) *ssa.Function {
	switch typ {
	case rtypeType:
		return i.rtypeMethods[meth.Id()]
	case errorType:
		return i.errorMethods[meth.Id()]
	}
	return i.prog.LookupMethod(typ, meth.Pkg(), meth.Name())
}
Exemplo n.º 10
0
func (g *javaGen) funcSignature(o *types.Func, static bool) error {
	sig := o.Type().(*types.Signature)
	res := sig.Results()

	var returnsError bool
	var ret string
	switch res.Len() {
	case 2:
		if !isErrorType(res.At(1).Type()) {
			return fmt.Errorf("second result value must be of type error: %s", o)
		}
		returnsError = true
		ret = g.javaType(res.At(0).Type())
	case 1:
		if isErrorType(res.At(0).Type()) {
			returnsError = true
			ret = "void"
		} else {
			ret = g.javaType(res.At(0).Type())
		}
	case 0:
		ret = "void"
	default:
		return fmt.Errorf("too many result values: %s", o)
	}

	g.Printf("public ")
	if static {
		g.Printf("static ")
	}
	g.Printf("%s %s(", ret, o.Name())
	params := sig.Params()
	for i := 0; i < params.Len(); i++ {
		if i > 0 {
			g.Printf(", ")
		}
		v := sig.Params().At(i)
		name := paramName(params, i)
		jt := g.javaType(v.Type())
		g.Printf("%s %s", jt, name)
	}
	g.Printf(")")
	if returnsError {
		g.Printf(" throws Exception")
	}
	return nil
}
Exemplo n.º 11
0
func (g *goGen) genFuncBody(o *types.Func, selectorLHS string) {
	sig := o.Type().(*types.Signature)
	params := sig.Params()
	for i := 0; i < params.Len(); i++ {
		p := params.At(i)
		g.genRead("param_"+paramName(params, i), "in", p.Type())
	}

	res := sig.Results()
	if res.Len() > 2 || res.Len() == 2 && !isErrorType(res.At(1).Type()) {
		g.errorf("functions and methods must return either zero or one values, and optionally an error")
		return
	}
	returnsValue := false
	returnsError := false
	if res.Len() == 1 {
		if isErrorType(res.At(0).Type()) {
			returnsError = true
			g.Printf("err := ")
		} else {
			returnsValue = true
			g.Printf("res := ")
		}
	} else if res.Len() == 2 {
		returnsValue = true
		returnsError = true
		g.Printf("res, err := ")
	}

	g.Printf("%s.%s(", selectorLHS, o.Name())
	for i := 0; i < params.Len(); i++ {
		if i > 0 {
			g.Printf(", ")
		}
		g.Printf("param_%s", paramName(params, i))
	}
	g.Printf(")\n")

	if returnsValue {
		g.genWrite("res", "out", res.At(0).Type())
	}
	if returnsError {
		g.genWrite("err", "out", res.At(res.Len()-1).Type())
	}
}
Exemplo n.º 12
0
func checkFuncValue(t *testing.T, prog *ssa.Program, obj *types.Func) {
	fn := prog.FuncValue(obj)
	// fmt.Printf("FuncValue(%s) = %s\n", obj, fn) // debugging
	if fn == nil {
		if obj.Name() != "interfaceMethod" {
			t.Errorf("FuncValue(%s) == nil", obj)
		}
		return
	}
	if fnobj := fn.Object(); fnobj != obj {
		t.Errorf("FuncValue(%s).Object() == %s; value was %s",
			obj, fnobj, fn.Name())
		return
	}
	if !types.Identical(fn.Type(), obj.Type()) {
		t.Errorf("FuncValue(%s).Type() == %s", obj, fn.Type())
		return
	}
}
Exemplo n.º 13
0
func (g *goGen) genFunc(o *types.Func) {
	sig := o.Type().(*types.Signature)

	params := "(" + g.tupleString(sig.Params()) + ")"
	ret := g.tupleString(sig.Results())
	if sig.Results().Len() > 1 {
		ret = "(" + ret + ") "
	} else {
		ret += " "
	}

	//funcName := o.Name()
	g.Printf(`
//export GoPy_%[1]s
// GoPy_%[1]s wraps %[2]s
func GoPy_%[1]s%[3]v%[4]v{
`,
		o.Name(), o.FullName(),
		params,
		ret,
	)

	g.Indent()
	g.genFuncBody(o)
	g.Outdent()
	g.Printf("}\n\n")
}
Exemplo n.º 14
0
func (p *Processor) tryMatchNewFunc(models []*Model, fun *types.Func) {
	modelName := fun.Name()[len("new"):]

	for _, m := range models {
		if m.Name != modelName {
			continue
		}

		sig := fun.Type().(*types.Signature)

		if sig.Recv() != nil {
			continue
		}

		res := sig.Results()
		for i := 0; i < res.Len(); i++ {
			if isTypeOrPtrTo(res.At(i).Type(), m.CheckedNode) {
				m.NewFunc = fun
				return
			}
		}
	}
}
Exemplo n.º 15
0
// makeBound returns a bound method wrapper (or "bound"), a synthetic
// function that delegates to a concrete or interface method denoted
// by obj.  The resulting function has no receiver, but has one free
// variable which will be used as the method's receiver in the
// tail-call.
//
// Use MakeClosure with such a wrapper to construct a bound method
// closure.  e.g.:
//
//   type T int          or:  type T interface { meth() }
//   func (t T) meth()
//   var t T
//   f := t.meth
//   f() // calls t.meth()
//
// f is a closure of a synthetic wrapper defined as if by:
//
//   f := func() { return t.meth() }
//
// Unlike makeWrapper, makeBound need perform no indirection or field
// selections because that can be done before the closure is
// constructed.
//
// EXCLUSIVE_LOCKS_ACQUIRED(meth.Prog.methodsMu)
//
func makeBound(prog *Program, obj *types.Func) *Function {
	prog.methodsMu.Lock()
	defer prog.methodsMu.Unlock()
	fn, ok := prog.bounds[obj]
	if !ok {
		description := fmt.Sprintf("bound method wrapper for %s", obj)
		if prog.mode&LogSource != 0 {
			defer logStack("%s", description)()
		}
		fn = &Function{
			name:      obj.Name() + "$bound",
			object:    obj,
			Signature: changeRecv(obj.Type().(*types.Signature), nil), // drop receiver
			Synthetic: description,
			Prog:      prog,
			pos:       obj.Pos(),
		}

		fv := &FreeVar{name: "recv", typ: recvType(obj), parent: fn}
		fn.FreeVars = []*FreeVar{fv}
		fn.startBody()
		createParams(fn, 0)
		var c Call

		if !isInterface(recvType(obj)) { // concrete
			c.Call.Value = prog.declaredFunc(obj)
			c.Call.Args = []Value{fv}
		} else {
			c.Call.Value = fv
			c.Call.Method = obj
		}
		for _, arg := range fn.Params {
			c.Call.Args = append(c.Call.Args, arg)
		}
		emitTailCall(fn, &c)
		fn.finishBody()

		prog.bounds[obj] = fn
	}
	return fn
}
Exemplo n.º 16
0
// checkMethod performs safety checks for renaming a method.
// There are three hazards:
// - declaration conflicts
// - selection ambiguity/changes
// - entailed renamings of assignable concrete/interface types (for now, just reject)
func (r *renamer) checkMethod(from *types.Func) {
	// e.g. error.Error
	if from.Pkg() == nil {
		r.errorf(from.Pos(), "you cannot rename built-in method %s", from)
		return
	}

	// As always, having to support concrete methods with pointer
	// and non-pointer receivers, and named vs unnamed types with
	// methods, makes tooling fun.

	// ASSIGNABILITY
	//
	// For now, if any method renaming breaks a required
	// assignability to another type, we reject it.
	//
	// TODO(adonovan): probably we should compute the entailed
	// renamings so that an interface method renaming causes
	// concrete methods to change too.  But which ones?
	//
	// There is no correct answer, only heuristics, because Go's
	// "duck typing" doesn't distinguish intentional from contingent
	// assignability.  There are two obvious approaches:
	//
	// (1) Update the minimum set of types to preserve the
	//     assignability of types all syntactic assignments
	//     (incl. implicit ones in calls, returns, sends, etc).
	//     The satisfy.Finder enumerates these.
	//     This is likely to be an underapproximation.
	//
	// (2) Update all types that are assignable to/from the changed
	//     type.  This requires computing the "implements" relation
	//     for all pairs of types (as godoc and oracle do).
	//     This is likely to be an overapproximation.
	//
	// If a concrete type is renamed, we probably do not want to
	// rename corresponding interfaces; interface renamings should
	// probably be initiated at the interface.  (But what if a
	// concrete type implements multiple interfaces with the same
	// method?  Then the user is stuck.)
	//
	// We need some experience before we decide how to implement this.

	// Check for conflict at point of declaration.
	// Check to ensure preservation of assignability requirements.
	recv := from.Type().(*types.Signature).Recv().Type()
	if isInterface(recv) {
		// Abstract method

		// declaration
		prev, _, _ := types.LookupFieldOrMethod(recv, false, from.Pkg(), r.to)
		if prev != nil {
			r.errorf(from.Pos(), "renaming this interface method %q to %q",
				from.Name(), r.to)
			r.errorf(prev.Pos(), "\twould conflict with this method")
			return
		}

		// Check all interfaces that embed this one for
		// declaration conflicts too.
		for _, info := range r.packages {
			// Start with named interface types (better errors)
			for _, obj := range info.Defs {
				if obj, ok := obj.(*types.TypeName); ok && isInterface(obj.Type()) {
					f, _, _ := types.LookupFieldOrMethod(
						obj.Type(), false, from.Pkg(), from.Name())
					if f == nil {
						continue
					}
					t, _, _ := types.LookupFieldOrMethod(
						obj.Type(), false, from.Pkg(), r.to)
					if t == nil {
						continue
					}
					r.errorf(from.Pos(), "renaming this interface method %q to %q",
						from.Name(), r.to)
					r.errorf(t.Pos(), "\twould conflict with this method")
					r.errorf(obj.Pos(), "\tin named interface type %q", obj.Name())
				}
			}

			// Now look at all literal interface types (includes named ones again).
			for e, tv := range info.Types {
				if e, ok := e.(*ast.InterfaceType); ok {
					_ = e
					_ = tv.Type.(*types.Interface)
					// TODO(adonovan): implement same check as above.
				}
			}
		}

		// assignability
		for T := range r.findAssignments(recv) {
			if obj, _, _ := types.LookupFieldOrMethod(T, false, from.Pkg(), from.Name()); obj == nil {
				continue
			}

			r.errorf(from.Pos(), "renaming this method %q to %q",
				from.Name(), r.to)
			var pos token.Pos
			var other string
			if named, ok := T.(*types.Named); ok {
				pos = named.Obj().Pos()
				other = named.Obj().Name()
			} else {
				pos = from.Pos()
				other = T.String()
			}
			r.errorf(pos, "\twould make %s no longer assignable to it", other)
			return
		}
	} else {
		// Concrete method

		// declaration
		prev, indices, _ := types.LookupFieldOrMethod(recv, true, from.Pkg(), r.to)
		if prev != nil && len(indices) == 1 {
			r.errorf(from.Pos(), "renaming this method %q to %q",
				from.Name(), r.to)
			r.errorf(prev.Pos(), "\twould conflict with this %s",
				objectKind(prev))
			return
		}

		// assignability (of both T and *T)
		recvBase := deref(recv)
		for _, R := range []types.Type{recvBase, types.NewPointer(recvBase)} {
			for I := range r.findAssignments(R) {
				if obj, _, _ := types.LookupFieldOrMethod(I, true, from.Pkg(), from.Name()); obj == nil {
					continue
				}
				r.errorf(from.Pos(), "renaming this method %q to %q",
					from.Name(), r.to)
				var pos token.Pos
				var iface string
				if named, ok := I.(*types.Named); ok {
					pos = named.Obj().Pos()
					iface = "interface " + named.Obj().Name()
				} else {
					pos = from.Pos()
					iface = I.String()
				}
				r.errorf(pos, "\twould make it no longer assignable to %s", iface)
				return // one is enough
			}
		}
	}

	// Check integrity of existing (field and method) selections.
	// We skip this if there were errors above, to avoid redundant errors.
	r.checkSelections(from)
}
Exemplo n.º 17
0
func (g *objcGen) funcSummary(obj *types.Func) *funcSummary {
	s := &funcSummary{name: obj.Name()}

	sig := obj.Type().(*types.Signature)
	params := sig.Params()
	for i := 0; i < params.Len(); i++ {
		p := params.At(i)
		v := paramInfo{
			typ:  p.Type(),
			name: paramName(params, i),
		}
		s.params = append(s.params, v)
	}

	res := sig.Results()
	switch res.Len() {
	case 0:
		s.ret = "void"
	case 1:
		p := res.At(0)
		if isErrorType(p.Type()) {
			s.retParams = append(s.retParams, paramInfo{
				typ:  p.Type(),
				name: "error",
			})
			s.ret = "BOOL"
		} else {
			name := p.Name()
			if name == "" || paramRE.MatchString(name) {
				name = "ret0_"
			}
			typ := p.Type()
			s.retParams = append(s.retParams, paramInfo{typ: typ, name: name})
			s.ret = g.objcType(typ)
		}
	case 2:
		name := res.At(0).Name()
		if name == "" || paramRE.MatchString(name) {
			name = "ret0_"
		}
		s.retParams = append(s.retParams, paramInfo{
			typ:  res.At(0).Type(),
			name: name,
		})

		if !isErrorType(res.At(1).Type()) {
			g.errorf("second result value must be of type error: %s", obj)
			return nil
		}
		s.retParams = append(s.retParams, paramInfo{
			typ:  res.At(1).Type(),
			name: "error", // TODO(hyangah): name collision check.
		})
		s.ret = "BOOL"
	default:
		// TODO(hyangah): relax the constraint on multiple return params.
		g.errorf("too many result values: %s", obj)
		return nil
	}

	return s
}
Exemplo n.º 18
0
// Implements displays the "implements" relation as it pertains to the
// selected type.
// If the selection is a method, 'implements' displays
// the corresponding methods of the types that would have been reported
// by an implements query on the receiver type.
//
func implements(q *Query) error {
	lconf := loader.Config{Build: q.Build}
	allowErrors(&lconf)

	qpkg, err := importQueryPackage(q.Pos, &lconf)
	if err != nil {
		return err
	}

	// Set the packages to search.
	if len(q.Scope) > 0 {
		// Inspect all packages in the analysis scope, if specified.
		if err := setPTAScope(&lconf, q.Scope); err != nil {
			return err
		}
	} else {
		// Otherwise inspect the forward and reverse
		// transitive closure of the selected package.
		// (In theory even this is incomplete.)
		_, rev, _ := importgraph.Build(q.Build)
		for path := range rev.Search(qpkg) {
			lconf.ImportWithTests(path)
		}

		// TODO(adonovan): for completeness, we should also
		// type-check and inspect function bodies in all
		// imported packages.  This would be expensive, but we
		// could optimize by skipping functions that do not
		// contain type declarations.  This would require
		// changing the loader's TypeCheckFuncBodies hook to
		// provide the []*ast.File.
	}

	// Load/parse/type-check the program.
	lprog, err := lconf.Load()
	if err != nil {
		return err
	}
	q.Fset = lprog.Fset

	qpos, err := parseQueryPos(lprog, q.Pos, false)
	if err != nil {
		return err
	}

	// Find the selected type.
	path, action := findInterestingNode(qpos.info, qpos.path)

	var method *types.Func
	var T types.Type // selected type (receiver if method != nil)

	switch action {
	case actionExpr:
		// method?
		if id, ok := path[0].(*ast.Ident); ok {
			if obj, ok := qpos.info.ObjectOf(id).(*types.Func); ok {
				recv := obj.Type().(*types.Signature).Recv()
				if recv == nil {
					return fmt.Errorf("this function is not a method")
				}
				method = obj
				T = recv.Type()
			}
		}
	case actionType:
		T = qpos.info.TypeOf(path[0].(ast.Expr))
	}
	if T == nil {
		return fmt.Errorf("no type or method here")
	}

	// Find all named types, even local types (which can have
	// methods via promotion) and the built-in "error".
	var allNamed []types.Type
	for _, info := range lprog.AllPackages {
		for _, obj := range info.Defs {
			if obj, ok := obj.(*types.TypeName); ok {
				allNamed = append(allNamed, obj.Type())
			}
		}
	}
	allNamed = append(allNamed, types.Universe.Lookup("error").Type())

	var msets typeutil.MethodSetCache

	// Test each named type.
	var to, from, fromPtr []types.Type
	for _, U := range allNamed {
		if isInterface(T) {
			if msets.MethodSet(T).Len() == 0 {
				continue // empty interface
			}
			if isInterface(U) {
				if msets.MethodSet(U).Len() == 0 {
					continue // empty interface
				}

				// T interface, U interface
				if !types.Identical(T, U) {
					if types.AssignableTo(U, T) {
						to = append(to, U)
					}
					if types.AssignableTo(T, U) {
						from = append(from, U)
					}
				}
			} else {
				// T interface, U concrete
				if types.AssignableTo(U, T) {
					to = append(to, U)
				} else if pU := types.NewPointer(U); types.AssignableTo(pU, T) {
					to = append(to, pU)
				}
			}
		} else if isInterface(U) {
			if msets.MethodSet(U).Len() == 0 {
				continue // empty interface
			}

			// T concrete, U interface
			if types.AssignableTo(T, U) {
				from = append(from, U)
			} else if pT := types.NewPointer(T); types.AssignableTo(pT, U) {
				fromPtr = append(fromPtr, U)
			}
		}
	}

	var pos interface{} = qpos
	if nt, ok := deref(T).(*types.Named); ok {
		pos = nt.Obj()
	}

	// Sort types (arbitrarily) to ensure test determinism.
	sort.Sort(typesByString(to))
	sort.Sort(typesByString(from))
	sort.Sort(typesByString(fromPtr))

	var toMethod, fromMethod, fromPtrMethod []*types.Selection // contain nils
	if method != nil {
		for _, t := range to {
			toMethod = append(toMethod,
				types.NewMethodSet(t).Lookup(method.Pkg(), method.Name()))
		}
		for _, t := range from {
			fromMethod = append(fromMethod,
				types.NewMethodSet(t).Lookup(method.Pkg(), method.Name()))
		}
		for _, t := range fromPtr {
			fromPtrMethod = append(fromPtrMethod,
				types.NewMethodSet(t).Lookup(method.Pkg(), method.Name()))
		}
	}

	q.result = &implementsResult{
		qpos, T, pos, to, from, fromPtr, method, toMethod, fromMethod, fromPtrMethod,
	}
	return nil
}
Exemplo n.º 19
0
// On success, findObjects returns the list of objects named
// spec.fromName matching the spec.  On success, the result has exactly
// one element unless spec.searchFor!="", in which case it has at least one
// element.
//
func findObjects(info *loader.PackageInfo, spec *spec) ([]types.Object, error) {
	if spec.pkgMember == "" {
		if spec.searchFor == "" {
			panic(spec)
		}
		objects := searchDefs(&info.Info, spec.searchFor)
		if objects == nil {
			return nil, fmt.Errorf("no object %q declared in package %q",
				spec.searchFor, info.Pkg.Path())
		}
		return objects, nil
	}

	pkgMember := info.Pkg.Scope().Lookup(spec.pkgMember)
	if pkgMember == nil {
		return nil, fmt.Errorf("package %q has no member %q",
			info.Pkg.Path(), spec.pkgMember)
	}

	var searchFunc *types.Func
	if spec.typeMember == "" {
		// package member
		if spec.searchFor == "" {
			return []types.Object{pkgMember}, nil
		}

		// Search within pkgMember, which must be a function.
		searchFunc, _ = pkgMember.(*types.Func)
		if searchFunc == nil {
			return nil, fmt.Errorf("cannot search for %q within %s %q",
				spec.searchFor, objectKind(pkgMember), pkgMember)
		}
	} else {
		// field/method of type
		// e.g. (encoding/json.Decoder).Decode
		// or ::x within it.

		tName, _ := pkgMember.(*types.TypeName)
		if tName == nil {
			return nil, fmt.Errorf("%s.%s is a %s, not a type",
				info.Pkg.Path(), pkgMember.Name(), objectKind(pkgMember))
		}

		// search within named type.
		obj, _, _ := types.LookupFieldOrMethod(tName.Type(), true, info.Pkg, spec.typeMember)
		if obj == nil {
			return nil, fmt.Errorf("cannot find field or method %q of %s %s.%s",
				spec.typeMember, typeKind(tName.Type()), info.Pkg.Path(), tName.Name())
		}

		if spec.searchFor == "" {
			return []types.Object{obj}, nil
		}

		searchFunc, _ = obj.(*types.Func)
		if searchFunc == nil {
			return nil, fmt.Errorf("cannot search for local name %q within %s (%s.%s).%s; need a function",
				spec.searchFor, objectKind(obj), info.Pkg.Path(), tName.Name(),
				obj.Name())
		}
		if isInterface(tName.Type()) {
			return nil, fmt.Errorf("cannot search for local name %q within abstract method (%s.%s).%s",
				spec.searchFor, info.Pkg.Path(), tName.Name(), searchFunc.Name())
		}
	}

	// -- search within function or method --

	decl := funcDecl(info, searchFunc)
	if decl == nil {
		return nil, fmt.Errorf("cannot find syntax for %s", searchFunc) // can't happen?
	}

	var objects []types.Object
	for _, obj := range searchDefs(&info.Info, spec.searchFor) {
		// We use positions, not scopes, to determine whether
		// the obj is within searchFunc.  This is clumsy, but the
		// alternative, using the types.Scope tree, doesn't
		// account for non-lexical objects like fields and
		// interface methods.
		if decl.Pos() <= obj.Pos() && obj.Pos() < decl.End() && obj != searchFunc {
			objects = append(objects, obj)
		}
	}
	if objects == nil {
		return nil, fmt.Errorf("no local definition of %q within %s",
			spec.searchFor, searchFunc)
	}
	return objects, nil
}
Exemplo n.º 20
0
// recvType returns the receiver type of method obj.
func recvType(obj *types.Func) types.Type {
	return obj.Type().(*types.Signature).Recv().Type()
}
Exemplo n.º 21
0
// declaredFunc returns the concrete function/method denoted by obj.
// Panic ensues if there is none.
//
func (prog *Program) declaredFunc(obj *types.Func) *Function {
	if v := prog.packageLevelValue(obj); v != nil {
		return v.(*Function)
	}
	panic("no concrete method: " + obj.String())
}
Exemplo n.º 22
0
// checkMethod performs safety checks for renaming a method.
// There are three hazards:
// - declaration conflicts
// - selection ambiguity/changes
// - entailed renamings of assignable concrete/interface types.
//   We reject renamings initiated at concrete methods if it would
//   change the assignability relation.  For renamings of abstract
//   methods, we rename all methods transitively coupled to it via
//   assignability.
func (r *Unexporter) checkMethod(objsToUpdate map[types.Object]string, from *types.Func, to string) {
	// e.g. error.Error
	if from.Pkg() == nil {
		r.warn(from, r.errorf(from.Pos(), "you cannot rename built-in method %s", from))
		return
	}

	// ASSIGNABILITY: We reject renamings of concrete methods that
	// would break a 'satisfy' constraint; but renamings of abstract
	// methods are allowed to proceed, and we rename affected
	// concrete and abstract methods as necessary.  It is the
	// initial method that determines the policy.

	// Check for conflict at point of declaration.
	// Check to ensure preservation of assignability requirements.
	R := recv(from).Type()
	if isInterface(R) {
		// Abstract method

		// declaration
		prev, _, _ := types.LookupFieldOrMethod(R, false, from.Pkg(), to)
		if prev != nil {
			r.warn(from,
				r.errorf(from.Pos(), "renaming this interface method %q to %q",
					from.Name(), to),
				r.errorf(prev.Pos(), "\twould conflict with this method"))
			return
		}

		// Check all interfaces that embed this one for
		// declaration conflicts too.
		for _, info := range r.packages {
			// Start with named interface types (better errors)
			for _, obj := range info.Defs {
				if obj, ok := obj.(*types.TypeName); ok && isInterface(obj.Type()) {
					f, _, _ := types.LookupFieldOrMethod(
						obj.Type(), false, from.Pkg(), from.Name())
					if f == nil {
						continue
					}
					t, _, _ := types.LookupFieldOrMethod(
						obj.Type(), false, from.Pkg(), to)
					if t == nil {
						continue
					}
					r.warn(from,
						r.errorf(from.Pos(), "renaming this interface method %q to %q",
							from.Name(), to),
						r.errorf(t.Pos(), "\twould conflict with this method"),
						r.errorf(obj.Pos(), "\tin named interface type %q", obj.Name()))
				}
			}

			// Now look at all literal interface types (includes named ones again).
			for e, tv := range info.Types {
				if e, ok := e.(*ast.InterfaceType); ok {
					_ = e
					_ = tv.Type.(*types.Interface)
					// TODO(adonovan): implement same check as above.
				}
			}
		}

		// assignability
		//
		// Find the set of concrete or abstract methods directly
		// coupled to abstract method 'from' by some
		// satisfy.Constraint, and rename them too.
		for key := range r.satisfy() {
			// key = (lhs, rhs) where lhs is always an interface.

			lsel := r.msets.MethodSet(key.LHS).Lookup(from.Pkg(), from.Name())
			if lsel == nil {
				continue
			}
			rmethods := r.msets.MethodSet(key.RHS)
			rsel := rmethods.Lookup(from.Pkg(), from.Name())
			if rsel == nil {
				continue
			}

			// If both sides have a method of this name,
			// and one of them is m, the other must be coupled.
			var coupled *types.Func
			switch from {
			case lsel.Obj():
				coupled = rsel.Obj().(*types.Func)
			case rsel.Obj():
				coupled = lsel.Obj().(*types.Func)
			default:
				continue
			}

			// We must treat concrete-to-interface
			// constraints like an implicit selection C.f of
			// each interface method I.f, and check that the
			// renaming leaves the selection unchanged and
			// unambiguous.
			//
			// Fun fact: the implicit selection of C.f
			// 	type I interface{f()}
			// 	type C struct{I}
			// 	func (C) g()
			//      var _ I = C{} // here
			// yields abstract method I.f.  This can make error
			// messages less than obvious.
			//
			if !isInterface(key.RHS) {
				// The logic below was derived from checkSelections.

				rtosel := rmethods.Lookup(from.Pkg(), to)
				if rtosel != nil {
					rto := rtosel.Obj().(*types.Func)
					delta := len(rsel.Index()) - len(rtosel.Index())
					if delta < 0 {
						continue // no ambiguity
					}

					// TODO(adonovan): record the constraint's position.
					keyPos := token.NoPos

					rename := r.errorf(from.Pos(), "renaming this method %q to %q",
						from.Name(), to)
					if delta == 0 {
						// analogous to same-block conflict
						r.warn(from, rename,
							r.errorf(keyPos, "\twould make the %s method of %s invoked via interface %s ambiguous",
								to, key.RHS, key.LHS),
							r.errorf(rto.Pos(), "\twith (%s).%s",
								recv(rto).Type(), to))
					} else {
						// analogous to super-block conflict
						r.warn(from, rename,
							r.errorf(keyPos, "\twould change the %s method of %s invoked via interface %s",
								to, key.RHS, key.LHS),
							r.errorf(coupled.Pos(), "\tfrom (%s).%s",
								recv(coupled).Type(), to),
							r.errorf(rto.Pos(), "\tto (%s).%s",
								recv(rto).Type(), to))
					}
					return // one error is enough
				}
			}

			if !r.changeMethods {
				// This should be unreachable.
				r.warn(from,
					r.errorf(from.Pos(), "internal error: during renaming of abstract method %s", from),
					r.errorf(coupled.Pos(), "\tchangedMethods=false, coupled method=%s", coupled),
					r.errorf(from.Pos(), "\tPlease file a bug report"))
				return
			}

			// Rename the coupled method to preserve assignability.
			r.check(objsToUpdate, coupled, to)
		}
	} else {
		// Concrete method

		// declaration
		prev, indices, _ := types.LookupFieldOrMethod(R, true, from.Pkg(), to)
		if prev != nil && len(indices) == 1 {
			r.warn(from,
				r.errorf(from.Pos(), "renaming this method %q to %q",
					from.Name(), to),
				r.errorf(prev.Pos(), "\twould conflict with this %s",
					objectKind(prev)))
			return
		}

		// assignability
		//
		// Find the set of abstract methods coupled to concrete
		// method 'from' by some satisfy.Constraint, and rename
		// them too.
		//
		// Coupling may be indirect, e.g. I.f <-> C.f via type D.
		//
		// 	type I interface {f()}
		//	type C int
		//	type (C) f()
		//	type D struct{C}
		//	var _ I = D{}
		//
		for key := range r.satisfy() {
			// key = (lhs, rhs) where lhs is always an interface.
			if isInterface(key.RHS) {
				continue
			}
			rsel := r.msets.MethodSet(key.RHS).Lookup(from.Pkg(), from.Name())
			if rsel == nil || rsel.Obj() != from {
				continue // rhs does not have the method
			}
			lsel := r.msets.MethodSet(key.LHS).Lookup(from.Pkg(), from.Name())
			if lsel == nil {
				continue
			}
			imeth := lsel.Obj().(*types.Func)

			// imeth is the abstract method (e.g. I.f)
			// and key.RHS is the concrete coupling type (e.g. D).
			if !r.changeMethods {
				rename := r.errorf(from.Pos(), "renaming this method %q to %q",
					from.Name(), to)
				var pos token.Pos
				var iface string

				i := recv(imeth).Type()
				if named, ok := i.(*types.Named); ok {
					pos = named.Obj().Pos()
					iface = "interface " + named.Obj().Name()
				} else {
					pos = from.Pos()
					iface = i.String()
				}
				r.warn(from, rename,
					r.errorf(pos, "\twould make %s no longer assignable to %s",
						key.RHS, iface),
					r.errorf(imeth.Pos(), "\t(rename %s.%s if you intend to change both types)",
						i, from.Name()))
				return // one error is enough
			}

			// Rename the coupled interface method to preserve assignability.
			r.check(objsToUpdate, imeth, to)
		}
	}

	// Check integrity of existing (field and method) selections.
	// We skip this if there were errors above, to avoid redundant errors.
	r.checkSelections(objsToUpdate, from, to)
}
Exemplo n.º 23
0
// recv returns the method's receiver.
func recv(meth *types.Func) *types.Var {
	return meth.Type().(*types.Signature).Recv()
}
Exemplo n.º 24
0
// Implements displays the "implements" relation as it pertains to the
// selected type.  If the selection is a method, 'implements' displays
// the corresponding methods of the types that would have been reported
// by an implements query on the receiver type.
//
func implements(o *Oracle, qpos *QueryPos) (queryResult, error) {
	// Find the selected type.
	path, action := findInterestingNode(qpos.info, qpos.path)

	var method *types.Func
	var T types.Type // selected type (receiver if method != nil)

	switch action {
	case actionExpr:
		// method?
		if id, ok := path[0].(*ast.Ident); ok {
			if obj, ok := qpos.info.ObjectOf(id).(*types.Func); ok {
				recv := obj.Type().(*types.Signature).Recv()
				if recv == nil {
					return nil, fmt.Errorf("this function is not a method")
				}
				method = obj
				T = recv.Type()
			}
		}
	case actionType:
		T = qpos.info.TypeOf(path[0].(ast.Expr))
	}
	if T == nil {
		return nil, fmt.Errorf("no type or method here")
	}

	// Find all named types, even local types (which can have
	// methods via promotion) and the built-in "error".
	//
	// TODO(adonovan): include all packages in PTA scope too?
	// i.e. don't reduceScope?
	//
	var allNamed []types.Type
	for _, info := range o.typeInfo {
		for _, obj := range info.Defs {
			if obj, ok := obj.(*types.TypeName); ok {
				allNamed = append(allNamed, obj.Type())
			}
		}
	}
	allNamed = append(allNamed, types.Universe.Lookup("error").Type())

	var msets types.MethodSetCache

	// Test each named type.
	var to, from, fromPtr []types.Type
	for _, U := range allNamed {
		if isInterface(T) {
			if msets.MethodSet(T).Len() == 0 {
				continue // empty interface
			}
			if isInterface(U) {
				if msets.MethodSet(U).Len() == 0 {
					continue // empty interface
				}

				// T interface, U interface
				if !types.Identical(T, U) {
					if types.AssignableTo(U, T) {
						to = append(to, U)
					}
					if types.AssignableTo(T, U) {
						from = append(from, U)
					}
				}
			} else {
				// T interface, U concrete
				if types.AssignableTo(U, T) {
					to = append(to, U)
				} else if pU := types.NewPointer(U); types.AssignableTo(pU, T) {
					to = append(to, pU)
				}
			}
		} else if isInterface(U) {
			if msets.MethodSet(U).Len() == 0 {
				continue // empty interface
			}

			// T concrete, U interface
			if types.AssignableTo(T, U) {
				from = append(from, U)
			} else if pT := types.NewPointer(T); types.AssignableTo(pT, U) {
				fromPtr = append(fromPtr, U)
			}
		}
	}

	var pos interface{} = qpos
	if nt, ok := deref(T).(*types.Named); ok {
		pos = nt.Obj()
	}

	// Sort types (arbitrarily) to ensure test determinism.
	sort.Sort(typesByString(to))
	sort.Sort(typesByString(from))
	sort.Sort(typesByString(fromPtr))

	var toMethod, fromMethod, fromPtrMethod []*types.Selection // contain nils
	if method != nil {
		for _, t := range to {
			toMethod = append(toMethod,
				types.NewMethodSet(t).Lookup(method.Pkg(), method.Name()))
		}
		for _, t := range from {
			fromMethod = append(fromMethod,
				types.NewMethodSet(t).Lookup(method.Pkg(), method.Name()))
		}
		for _, t := range fromPtr {
			fromPtrMethod = append(fromPtrMethod,
				types.NewMethodSet(t).Lookup(method.Pkg(), method.Name()))
		}
	}

	return &implementsResult{qpos, T, pos, to, from, fromPtr, method, toMethod, fromMethod, fromPtrMethod}, nil
}
Exemplo n.º 25
0
func (e *Export) checkMethod(from *types.Func, to string) {
	// e.g. error.Error
	if from.Pkg() == nil {
		e.Conflicting = true
		return
	}

	// ASSIGNABILITY: We reject renamings of concrete methods that
	// would break a 'satisfy' constraint; but renamings of abstract
	// methods are allowed to proceed, and we rename affected
	// concrete and abstract methods as necessary.  It is the
	// initial method that determines the policy.

	// Check for conflict at point of declaration.
	// Check to ensure preservation of assignability requirements.
	R := recv(from).Type()
	if isInterface(R) {
		// Abstract method

		// declaration
		prev, _, _ := types.LookupFieldOrMethod(R, false, from.Pkg(), to)
		if prev != nil {
			e.Conflicting = true
			return
		}

		// Check all interfaces that embed this one for
		// declaration conflicts too.
		for _, info := range e.u.prog.AllPackages {
			// Start with named interface types (better errors)
			for _, obj := range info.Defs {
				if obj, ok := obj.(*types.TypeName); ok && isInterface(obj.Type()) {
					f, _, _ := types.LookupFieldOrMethod(
						obj.Type(), false, from.Pkg(), from.Name())
					if f == nil {
						continue
					}
					t, _, _ := types.LookupFieldOrMethod(obj.Type(), false, from.Pkg(), to)
					if t == nil {
						continue
					}
					e.Conflicting = true
					return
				}
			}
		}

		// assignability
		//
		// Find the set of concrete or abstract methods directly
		// coupled to abstract method 'from' by some
		// satisfy.Constraint, and rename them too.
		for key := range e.u.satisfy() {
			// key = (lhs, rhs) where lhs is always an interface.

			lsel := e.u.msets.MethodSet(key.LHS).Lookup(from.Pkg(), from.Name())
			if lsel == nil {
				continue
			}
			rmethods := e.u.msets.MethodSet(key.RHS)
			rsel := rmethods.Lookup(from.Pkg(), from.Name())
			if rsel == nil {
				continue
			}

			// If both sides have a method of this name,
			// and one of them is m, the other must be coupled.
			var coupled *types.Func
			switch from {
			case lsel.Obj():
				coupled = rsel.Obj().(*types.Func)
			case rsel.Obj():
				coupled = lsel.Obj().(*types.Func)
			default:
				continue
			}

			// We must treat concrete-to-interface
			// constraints like an implicit selection C.f of
			// each interface method I.f, and check that the
			// renaming leaves the selection unchanged and
			// unambiguous.
			//
			// Fun fact: the implicit selection of C.f
			// 	type I interface{f()}
			// 	type C struct{I}
			// 	func (C) g()
			//      var _ I = C{} // here
			// yields abstract method I.f.  This can make error
			// messages less than obvious.
			//
			if !isInterface(key.RHS) {
				// The logic below was derived from checkSelections.

				rtosel := rmethods.Lookup(from.Pkg(), to)
				if rtosel != nil {
					delta := len(rsel.Index()) - len(rtosel.Index())
					if delta < 0 {
						continue // no ambiguity
					}
					e.Conflicting = true
					return
				}
			}

			// Rename the coupled method to preserve assignability.
			e.check(coupled, to)
		}
	}

	// Concrete method

	// declaration
	prev, indices, _ := types.LookupFieldOrMethod(R, true, from.Pkg(), to)
	if prev != nil && len(indices) == 1 {
		e.Conflicting = true
		return
	}

	// assignability
	//
	// Find the set of abstract methods coupled to concrete
	// method 'from' by some satisfy.Constraint, and rename
	// them too.
	//
	// Coupling may be indirect, e.g. I.f <-> C.f via type D.
	//
	// 	type I interface {f()}
	//	type C int
	//	type (C) f()
	//	type D struct{C}
	//	var _ I = D{}
	//
	for key := range e.u.satisfy() {
		// key = (lhs, rhs) where lhs is always an interface.
		if isInterface(key.RHS) {
			continue
		}
		rsel := e.u.msets.MethodSet(key.RHS).Lookup(from.Pkg(), from.Name())
		if rsel == nil || rsel.Obj() != from {
			continue // rhs does not have the method
		}
		lsel := e.u.msets.MethodSet(key.LHS).Lookup(from.Pkg(), from.Name())
		if lsel == nil {
			continue
		}
		imeth := lsel.Obj().(*types.Func)
		e.check(imeth, to)
	}

	// Check integrity of existing (field and method) selections.
	// We skip this if there were errors above, to avoid redundant errors.
	e.checkSelections(from, to)
}
Exemplo n.º 26
0
func (g *cpyGen) genFuncBody(o *types.Func) {

	funcArgs := []string{}

	sig := o.Type().(*types.Signature)
	res := newVars(sig.Results())
	args := newVars(sig.Params())
	for _, arg := range args {
		arg.genDecl(g.impl)
		funcArgs = append(funcArgs, arg.getFuncArg())
	}

	// FIXME(sbinet) pythonize (turn errors into python exceptions)
	if len(res) > 0 {
		switch len(res) {
		case 1:
			ret := res[0]
			ret.genRetDecl(g.impl)
		default:
			g.impl.Printf("struct %[1]s_return c_gopy_ret;\n", o.Name())
			/*
					for i := 0; i < res.Len(); i++ {
						ret := res.At(i)
						n := ret.Name()
						if n == "" {
							n = "gopy_" + strconv.Itoa(i)
						}
						g.impl.Printf("%[1]s c_%[2]s;\n", ctypeName(ret.Type()), n)
				    }
			*/
		}
	}

	g.impl.Printf("\n")

	if len(args) > 0 {
		g.impl.Printf("if (!PyArg_ParseTuple(args, ")
		format := []string{}
		pyaddrs := []string{}
		for _, arg := range args {
			pyfmt, addr := arg.getArgParse()
			format = append(format, pyfmt)
			pyaddrs = append(pyaddrs, addr)
		}
		g.impl.Printf("%q, %s)) {\n", strings.Join(format, ""), strings.Join(pyaddrs, ", "))
		g.impl.Indent()
		g.impl.Printf("return NULL;\n")
		g.impl.Outdent()
		g.impl.Printf("}\n\n")
	}

	if len(args) > 0 {
		for _, arg := range args {
			arg.genFuncPreamble(g.impl)
		}
		g.impl.Printf("\n")
	}

	if len(res) > 0 {
		g.impl.Printf("c_gopy_ret = ")
	}

	g.impl.Printf("GoPy_%[1]s(%[2]s);\n", o.Name(), strings.Join(funcArgs, ", "))

	g.impl.Printf("\n")

	if len(res) <= 0 {
		g.impl.Printf("Py_INCREF(Py_None);\nreturn Py_None;\n")
		return
	}

	format := []string{}
	funcArgs = []string{}
	switch len(res) {
	case 1:
		ret := res[0]
		pyfmt, _ := ret.getArgParse()
		format = append(format, pyfmt)
		funcArgs = append(funcArgs, "c_gopy_ret")
	default:
		for _, ret := range res {
			pyfmt, _ := ret.getArgParse()
			format = append(format, pyfmt)
			funcArgs = append(funcArgs, ret.getFuncArg())
		}
	}

	g.impl.Printf("return Py_BuildValue(%q, %s);\n",
		strings.Join(format, ""),
		strings.Join(funcArgs, ", "),
	)
	//g.impl.Printf("return NULL;\n")
}