func hasType(pkg *grinder.Package, fn *ast.FuncDecl, x, v ast.Expr) bool {
// Does x (by itself) default to v's type?
// Find the scope in which x appears.
xScope := pkg.Info.Scopes[fn.Type]
ast.Inspect(fn.Body, func(z ast.Node) bool {
if z == nil {
return false
}
if x.Pos() < z.Pos() || z.End() <= x.Pos() {
return false
}
scope := pkg.Info.Scopes[z]
if scope != nil {
xScope = scope
}
return true
})
xt, err := types.EvalNode(pkg.FileSet, x, pkg.Types, xScope)
if err != nil {
return false
}
vt := pkg.Info.Types[v]
if types.Identical(xt.Type, vt.Type) {
return true
}
// Might be untyped.
vb, ok1 := vt.Type.(*types.Basic)
xb, ok2 := xt.Type.(*types.Basic)
if ok1 && ok2 {
switch xb.Kind() {
case types.UntypedInt:
return vb.Kind() == types.Int
case types.UntypedBool:
return vb.Kind() == types.Bool
case types.UntypedRune:
return vb.Kind() == types.Rune
case types.UntypedFloat:
return vb.Kind() == types.Float64
case types.UntypedComplex:
return vb.Kind() == types.Complex128
case types.UntypedString:
return vb.Kind() == types.String
}
}
return false
}
// isUntypedConst reports whether expr is an untyped constant,
// and indicates what its default type is.
// scope may be nil.
func (f *file) isUntypedConst(expr ast.Expr, scope *types.Scope) (defType string, ok bool) {
typ := f.pkg.typeOf(expr)
if typ == nil || scope == nil {
return "", false
}
// Re-evaluate expr outside of its context to see if it's untyped.
// (An expr evaluated within, for example, an assignment context will get the type of the LHS.)
tv, err := types.EvalNode(f.fset, expr, f.pkg.typesPkg, scope)
if err != nil {
return "", false
}
if b, ok := tv.Type.(*types.Basic); ok {
if dt, ok := basicTypeKinds[b.Kind()]; ok {
return dt, true
}
}
return "", false
}
func doOneInput(input, filename string) bool {
var conf loader.Config
// Parsing.
f, err := conf.ParseFile(filename, input)
if err != nil {
fmt.Println(err)
return false
}
// Create single-file main package and import its dependencies.
conf.CreateFromFiles("main", f)
iprog, err := conf.Load()
if err != nil {
fmt.Println(err)
return false
}
mainPkgInfo := iprog.Created[0].Pkg
// SSA creation + building.
prog := ssa.Create(iprog, ssa.SanityCheckFunctions)
prog.BuildAll()
mainpkg := prog.Package(mainPkgInfo)
ptrmain := mainpkg // main package for the pointer analysis
if mainpkg.Func("main") == nil {
// No main function; assume it's a test.
ptrmain = prog.CreateTestMainPackage(mainpkg)
}
// Find all calls to the built-in print(x). Analytically,
// print is a no-op, but it's a convenient hook for testing
// the PTS of an expression, so our tests use it.
probes := make(map[*ssa.CallCommon]bool)
for fn := range ssautil.AllFunctions(prog) {
if fn.Pkg == mainpkg {
for _, b := range fn.Blocks {
for _, instr := range b.Instrs {
if instr, ok := instr.(ssa.CallInstruction); ok {
call := instr.Common()
if b, ok := call.Value.(*ssa.Builtin); ok && b.Name() == "print" && len(call.Args) == 1 {
probes[instr.Common()] = true
}
}
}
}
}
}
ok := true
lineMapping := make(map[string]string) // maps "file:line" to @line tag
// Parse expectations in this input.
var exps []*expectation
re := regexp.MustCompile("// *@([a-z]*) *(.*)$")
lines := strings.Split(input, "\n")
for linenum, line := range lines {
linenum++ // make it 1-based
if matches := re.FindAllStringSubmatch(line, -1); matches != nil {
match := matches[0]
kind, rest := match[1], match[2]
e := &expectation{kind: kind, filename: filename, linenum: linenum}
if kind == "line" {
if rest == "" {
ok = false
e.errorf("@%s expectation requires identifier", kind)
} else {
lineMapping[fmt.Sprintf("%s:%d", filename, linenum)] = rest
}
continue
}
if e.needsProbe() && !strings.Contains(line, "print(") {
ok = false
e.errorf("@%s expectation must follow call to print(x)", kind)
continue
}
switch kind {
case "pointsto":
e.args = split(rest, "|")
case "types":
for _, typstr := range split(rest, "|") {
var t types.Type = types.Typ[types.Invalid] // means "..."
if typstr != "..." {
texpr, err := parser.ParseExpr(typstr)
if err != nil {
ok = false
// Don't print err since its location is bad.
e.errorf("'%s' is not a valid type", typstr)
continue
}
mainFileScope := mainpkg.Object.Scope().Child(0)
tv, err := types.EvalNode(prog.Fset, texpr, mainpkg.Object, mainFileScope)
if err != nil {
ok = false
// Don't print err since its location is bad.
e.errorf("'%s' is not a valid type: %s", typstr, err)
continue
}
t = tv.Type
}
e.types = append(e.types, t)
}
case "calls":
e.args = split(rest, "->")
// TODO(adonovan): eagerly reject the
// expectation if fn doesn't denote
// existing function, rather than fail
// the expectation after analysis.
if len(e.args) != 2 {
ok = false
e.errorf("@calls expectation wants 'caller -> callee' arguments")
continue
}
case "warning":
lit, err := strconv.Unquote(strings.TrimSpace(rest))
if err != nil {
ok = false
e.errorf("couldn't parse @warning operand: %s", err.Error())
continue
}
e.args = append(e.args, lit)
default:
ok = false
e.errorf("unknown expectation kind: %s", e)
continue
}
exps = append(exps, e)
}
}
var log bytes.Buffer
fmt.Fprintf(&log, "Input: %s\n", filename)
// Run the analysis.
config := &pointer.Config{
Reflection: true,
BuildCallGraph: true,
Mains: []*ssa.Package{ptrmain},
Log: &log,
}
for probe := range probes {
v := probe.Args[0]
if pointer.CanPoint(v.Type()) {
config.AddQuery(v)
}
}
// Print the log is there was an error or a panic.
complete := false
defer func() {
if !complete || !ok {
log.WriteTo(os.Stderr)
}
}()
result, err := pointer.Analyze(config)
if err != nil {
panic(err) // internal error in pointer analysis
}
// Check the expectations.
for _, e := range exps {
var call *ssa.CallCommon
var pts pointer.PointsToSet
var tProbe types.Type
if e.needsProbe() {
if call, pts = findProbe(prog, probes, result.Queries, e); call == nil {
ok = false
e.errorf("unreachable print() statement has expectation %s", e)
continue
}
tProbe = call.Args[0].Type()
if !pointer.CanPoint(tProbe) {
ok = false
e.errorf("expectation on non-pointerlike operand: %s", tProbe)
continue
}
}
switch e.kind {
case "pointsto":
if !checkPointsToExpectation(e, pts, lineMapping, prog) {
ok = false
}
case "types":
if !checkTypesExpectation(e, pts, tProbe) {
ok = false
}
case "calls":
if !checkCallsExpectation(prog, e, result.CallGraph) {
ok = false
}
case "warning":
if !checkWarningExpectation(prog, e, result.Warnings) {
ok = false
}
}
}
complete = true
// ok = false // debugging: uncomment to always see log
return ok
}