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// Copyright 2017 The Bazel 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 starlark_test
import (
"bytes"
"fmt"
"math"
"os/exec"
"path/filepath"
"reflect"
"sort"
"strings"
"testing"
"go.starlark.net/internal/chunkedfile"
"go.starlark.net/resolve"
"go.starlark.net/starlark"
"go.starlark.net/starlarkjson"
"go.starlark.net/starlarkstruct"
"go.starlark.net/starlarktest"
"go.starlark.net/syntax"
)
// A test may enable non-standard options by containing (e.g.) "option:recursion".
func setOptions(src string) {
resolve.AllowGlobalReassign = option(src, "globalreassign")
resolve.LoadBindsGlobally = option(src, "loadbindsglobally")
resolve.AllowRecursion = option(src, "recursion")
resolve.AllowSet = option(src, "set")
}
func option(chunk, name string) bool {
return strings.Contains(chunk, "option:"+name)
}
// Wrapper is the type of errors with an Unwrap method; see https://golang.org/pkg/errors.
type Wrapper interface {
Unwrap() error
}
func TestEvalExpr(t *testing.T) {
// This is mostly redundant with the new *.star tests.
// TODO(adonovan): move checks into *.star files and
// reduce this to a mere unit test of starlark.Eval.
thread := new(starlark.Thread)
for _, test := range []struct{ src, want string }{
{`123`, `123`},
{`-1`, `-1`},
{`"a"+"b"`, `"ab"`},
{`1+2`, `3`},
// lists
{`[]`, `[]`},
{`[1]`, `[1]`},
{`[1,]`, `[1]`},
{`[1, 2]`, `[1, 2]`},
{`[2 * x for x in [1, 2, 3]]`, `[2, 4, 6]`},
{`[2 * x for x in [1, 2, 3] if x > 1]`, `[4, 6]`},
{`[(x, y) for x in [1, 2] for y in [3, 4]]`,
`[(1, 3), (1, 4), (2, 3), (2, 4)]`},
{`[(x, y) for x in [1, 2] if x == 2 for y in [3, 4]]`,
`[(2, 3), (2, 4)]`},
// tuples
{`()`, `()`},
{`(1)`, `1`},
{`(1,)`, `(1,)`},
{`(1, 2)`, `(1, 2)`},
{`(1, 2, 3, 4, 5)`, `(1, 2, 3, 4, 5)`},
{`1, 2`, `(1, 2)`},
// dicts
{`{}`, `{}`},
{`{"a": 1}`, `{"a": 1}`},
{`{"a": 1,}`, `{"a": 1}`},
// conditional
{`1 if 3 > 2 else 0`, `1`},
{`1 if "foo" else 0`, `1`},
{`1 if "" else 0`, `0`},
// indexing
{`["a", "b"][0]`, `"a"`},
{`["a", "b"][1]`, `"b"`},
{`("a", "b")[0]`, `"a"`},
{`("a", "b")[1]`, `"b"`},
{`"aΩb"[0]`, `"a"`},
{`"aΩb"[1]`, `"\xce"`},
{`"aΩb"[3]`, `"b"`},
{`{"a": 1}["a"]`, `1`},
{`{"a": 1}["b"]`, `key "b" not in dict`},
{`{}[[]]`, `unhashable type: list`},
{`{"a": 1}[[]]`, `unhashable type: list`},
{`[x for x in range(3)]`, "[0, 1, 2]"},
} {
var got string
if v, err := starlark.Eval(thread, "<expr>", test.src, nil); err != nil {
got = err.Error()
} else {
got = v.String()
}
if got != test.want {
t.Errorf("eval %s = %s, want %s", test.src, got, test.want)
}
}
}
func TestExecFile(t *testing.T) {
defer setOptions("")
testdata := starlarktest.DataFile("starlark", ".")
thread := &starlark.Thread{Load: load}
starlarktest.SetReporter(thread, t)
for _, file := range []string{
"testdata/assign.star",
"testdata/bool.star",
"testdata/builtins.star",
"testdata/bytes.star",
"testdata/control.star",
"testdata/dict.star",
"testdata/float.star",
"testdata/function.star",
"testdata/int.star",
"testdata/json.star",
"testdata/list.star",
"testdata/misc.star",
"testdata/set.star",
"testdata/string.star",
"testdata/tuple.star",
"testdata/recursion.star",
"testdata/module.star",
} {
filename := filepath.Join(testdata, file)
for _, chunk := range chunkedfile.Read(filename, t) {
predeclared := starlark.StringDict{
"hasfields": starlark.NewBuiltin("hasfields", newHasFields),
"fibonacci": fib{},
"struct": starlark.NewBuiltin("struct", starlarkstruct.Make),
}
setOptions(chunk.Source)
resolve.AllowLambda = true // used extensively
_, err := starlark.ExecFile(thread, filename, chunk.Source, predeclared)
switch err := err.(type) {
case *starlark.EvalError:
found := false
for i := range err.CallStack {
posn := err.CallStack.At(i).Pos
if posn.Filename() == filename {
chunk.GotError(int(posn.Line), err.Error())
found = true
break
}
}
if !found {
t.Error(err.Backtrace())
}
case nil:
// success
default:
t.Errorf("\n%s", err)
}
chunk.Done()
}
}
}
// A fib is an iterable value representing the infinite Fibonacci sequence.
type fib struct{}
func (t fib) Freeze() {}
func (t fib) String() string { return "fib" }
func (t fib) Type() string { return "fib" }
func (t fib) Truth() starlark.Bool { return true }
func (t fib) Hash() (uint32, error) { return 0, fmt.Errorf("fib is unhashable") }
func (t fib) Iterate() starlark.Iterator { return &fibIterator{0, 1} }
type fibIterator struct{ x, y int }
func (it *fibIterator) Next(p *starlark.Value) bool {
*p = starlark.MakeInt(it.x)
it.x, it.y = it.y, it.x+it.y
return true
}
func (it *fibIterator) Done() {}
// load implements the 'load' operation as used in the evaluator tests.
func load(thread *starlark.Thread, module string) (starlark.StringDict, error) {
if module == "assert.star" {
return starlarktest.LoadAssertModule()
}
if module == "json.star" {
return starlark.StringDict{"json": starlarkjson.Module}, nil
}
// TODO(adonovan): test load() using this execution path.
filename := filepath.Join(filepath.Dir(thread.CallFrame(0).Pos.Filename()), module)
return starlark.ExecFile(thread, filename, nil, nil)
}
func newHasFields(thread *starlark.Thread, b *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
if len(args)+len(kwargs) > 0 {
return nil, fmt.Errorf("%s: unexpected arguments", b.Name())
}
return &hasfields{attrs: make(map[string]starlark.Value)}, nil
}
// hasfields is a test-only implementation of HasAttrs.
// It permits any field to be set.
// Clients will likely want to provide their own implementation,
// so we don't have any public implementation.
type hasfields struct {
attrs starlark.StringDict
frozen bool
}
var (
_ starlark.HasAttrs = (*hasfields)(nil)
_ starlark.HasBinary = (*hasfields)(nil)
)
func (hf *hasfields) String() string { return "hasfields" }
func (hf *hasfields) Type() string { return "hasfields" }
func (hf *hasfields) Truth() starlark.Bool { return true }
func (hf *hasfields) Hash() (uint32, error) { return 42, nil }
func (hf *hasfields) Freeze() {
if !hf.frozen {
hf.frozen = true
for _, v := range hf.attrs {
v.Freeze()
}
}
}
func (hf *hasfields) Attr(name string) (starlark.Value, error) { return hf.attrs[name], nil }
func (hf *hasfields) SetField(name string, val starlark.Value) error {
if hf.frozen {
return fmt.Errorf("cannot set field on a frozen hasfields")
}
if strings.HasPrefix(name, "no") { // for testing
return starlark.NoSuchAttrError(fmt.Sprintf("no .%s field", name))
}
hf.attrs[name] = val
return nil
}
func (hf *hasfields) AttrNames() []string {
names := make([]string, 0, len(hf.attrs))
for key := range hf.attrs {
names = append(names, key)
}
sort.Strings(names)
return names
}
func (hf *hasfields) Binary(op syntax.Token, y starlark.Value, side starlark.Side) (starlark.Value, error) {
// This method exists so we can exercise 'list += x'
// where x is not Iterable but defines list+x.
if op == syntax.PLUS {
if _, ok := y.(*starlark.List); ok {
return starlark.MakeInt(42), nil // list+hasfields is 42
}
}
return nil, nil
}
func TestParameterPassing(t *testing.T) {
const filename = "parameters.go"
const src = `
def a():
return
def b(a, b):
return a, b
def c(a, b=42):
return a, b
def d(*args):
return args
def e(**kwargs):
return kwargs
def f(a, b=42, *args, **kwargs):
return a, b, args, kwargs
def g(a, b=42, *args, c=123, **kwargs):
return a, b, args, c, kwargs
def h(a, b=42, *, c=123, **kwargs):
return a, b, c, kwargs
def i(a, b=42, *, c, d=123, e, **kwargs):
return a, b, c, d, e, kwargs
def j(a, b=42, *args, c, d=123, e, **kwargs):
return a, b, args, c, d, e, kwargs
`
thread := new(starlark.Thread)
globals, err := starlark.ExecFile(thread, filename, src, nil)
if err != nil {
t.Fatal(err)
}
// All errors are dynamic; see resolver for static errors.
for _, test := range []struct{ src, want string }{
// a()
{`a()`, `None`},
{`a(1)`, `function a accepts no arguments (1 given)`},
// b(a, b)
{`b()`, `function b missing 2 arguments (a, b)`},
{`b(1)`, `function b missing 1 argument (b)`},
{`b(a=1)`, `function b missing 1 argument (b)`},
{`b(b=1)`, `function b missing 1 argument (a)`},
{`b(1, 2)`, `(1, 2)`},
{`b`, `<function b>`}, // asserts that b's parameter b was treated as a local variable
{`b(1, 2, 3)`, `function b accepts 2 positional arguments (3 given)`},
{`b(1, b=2)`, `(1, 2)`},
{`b(1, a=2)`, `function b got multiple values for parameter "a"`},
{`b(1, x=2)`, `function b got an unexpected keyword argument "x"`},
{`b(a=1, b=2)`, `(1, 2)`},
{`b(b=1, a=2)`, `(2, 1)`},
{`b(b=1, a=2, x=1)`, `function b got an unexpected keyword argument "x"`},
{`b(x=1, b=1, a=2)`, `function b got an unexpected keyword argument "x"`},
// c(a, b=42)
{`c()`, `function c missing 1 argument (a)`},
{`c(1)`, `(1, 42)`},
{`c(1, 2)`, `(1, 2)`},
{`c(1, 2, 3)`, `function c accepts at most 2 positional arguments (3 given)`},
{`c(1, b=2)`, `(1, 2)`},
{`c(1, a=2)`, `function c got multiple values for parameter "a"`},
{`c(a=1, b=2)`, `(1, 2)`},
{`c(b=1, a=2)`, `(2, 1)`},
// d(*args)
{`d()`, `()`},
{`d(1)`, `(1,)`},
{`d(1, 2)`, `(1, 2)`},
{`d(1, 2, k=3)`, `function d got an unexpected keyword argument "k"`},
{`d(args=[])`, `function d got an unexpected keyword argument "args"`},
// e(**kwargs)
{`e()`, `{}`},
{`e(1)`, `function e accepts 0 positional arguments (1 given)`},
{`e(k=1)`, `{"k": 1}`},
{`e(kwargs={})`, `{"kwargs": {}}`},
// f(a, b=42, *args, **kwargs)
{`f()`, `function f missing 1 argument (a)`},
{`f(0)`, `(0, 42, (), {})`},
{`f(0)`, `(0, 42, (), {})`},
{`f(0, 1)`, `(0, 1, (), {})`},
{`f(0, 1, 2)`, `(0, 1, (2,), {})`},
{`f(0, 1, 2, 3)`, `(0, 1, (2, 3), {})`},
{`f(a=0)`, `(0, 42, (), {})`},
{`f(0, b=1)`, `(0, 1, (), {})`},
{`f(0, a=1)`, `function f got multiple values for parameter "a"`},
{`f(0, b=1, c=2)`, `(0, 1, (), {"c": 2})`},
// g(a, b=42, *args, c=123, **kwargs)
{`g()`, `function g missing 1 argument (a)`},
{`g(0)`, `(0, 42, (), 123, {})`},
{`g(0, 1)`, `(0, 1, (), 123, {})`},
{`g(0, 1, 2)`, `(0, 1, (2,), 123, {})`},
{`g(0, 1, 2, 3)`, `(0, 1, (2, 3), 123, {})`},
{`g(a=0)`, `(0, 42, (), 123, {})`},
{`g(0, b=1)`, `(0, 1, (), 123, {})`},
{`g(0, a=1)`, `function g got multiple values for parameter "a"`},
{`g(0, b=1, c=2, d=3)`, `(0, 1, (), 2, {"d": 3})`},
// h(a, b=42, *, c=123, **kwargs)
{`h()`, `function h missing 1 argument (a)`},
{`h(0)`, `(0, 42, 123, {})`},
{`h(0, 1)`, `(0, 1, 123, {})`},
{`h(0, 1, 2)`, `function h accepts at most 2 positional arguments (3 given)`},
{`h(a=0)`, `(0, 42, 123, {})`},
{`h(0, b=1)`, `(0, 1, 123, {})`},
{`h(0, a=1)`, `function h got multiple values for parameter "a"`},
{`h(0, b=1, c=2)`, `(0, 1, 2, {})`},
{`h(0, b=1, d=2)`, `(0, 1, 123, {"d": 2})`},
{`h(0, b=1, c=2, d=3)`, `(0, 1, 2, {"d": 3})`},
// i(a, b=42, *, c, d=123, e, **kwargs)
{`i()`, `function i missing 3 arguments (a, c, e)`},
{`i(0)`, `function i missing 2 arguments (c, e)`},
{`i(0, 1)`, `function i missing 2 arguments (c, e)`},
{`i(0, 1, 2)`, `function i accepts at most 2 positional arguments (3 given)`},
{`i(0, 1, e=2)`, `function i missing 1 argument (c)`},
{`i(0, 1, 2, 3)`, `function i accepts at most 2 positional arguments (4 given)`},
{`i(a=0)`, `function i missing 2 arguments (c, e)`},
{`i(0, b=1)`, `function i missing 2 arguments (c, e)`},
{`i(0, a=1)`, `function i got multiple values for parameter "a"`},
{`i(0, b=1, c=2)`, `function i missing 1 argument (e)`},
{`i(0, b=1, d=2)`, `function i missing 2 arguments (c, e)`},
{`i(0, b=1, c=2, d=3)`, `function i missing 1 argument (e)`},
{`i(0, b=1, c=2, d=3, e=4)`, `(0, 1, 2, 3, 4, {})`},
{`i(0, 1, b=1, c=2, d=3, e=4)`, `function i got multiple values for parameter "b"`},
// j(a, b=42, *args, c, d=123, e, **kwargs)
{`j()`, `function j missing 3 arguments (a, c, e)`},
{`j(0)`, `function j missing 2 arguments (c, e)`},
{`j(0, 1)`, `function j missing 2 arguments (c, e)`},
{`j(0, 1, 2)`, `function j missing 2 arguments (c, e)`},
{`j(0, 1, e=2)`, `function j missing 1 argument (c)`},
{`j(0, 1, 2, 3)`, `function j missing 2 arguments (c, e)`},
{`j(a=0)`, `function j missing 2 arguments (c, e)`},
{`j(0, b=1)`, `function j missing 2 arguments (c, e)`},
{`j(0, a=1)`, `function j got multiple values for parameter "a"`},
{`j(0, b=1, c=2)`, `function j missing 1 argument (e)`},
{`j(0, b=1, d=2)`, `function j missing 2 arguments (c, e)`},
{`j(0, b=1, c=2, d=3)`, `function j missing 1 argument (e)`},
{`j(0, b=1, c=2, d=3, e=4)`, `(0, 1, (), 2, 3, 4, {})`},
{`j(0, 1, b=1, c=2, d=3, e=4)`, `function j got multiple values for parameter "b"`},
{`j(0, 1, 2, c=3, e=4)`, `(0, 1, (2,), 3, 123, 4, {})`},
} {
var got string
if v, err := starlark.Eval(thread, "<expr>", test.src, globals); err != nil {
got = err.Error()
} else {
got = v.String()
}
if got != test.want {
t.Errorf("eval %s = %s, want %s", test.src, got, test.want)
}
}
}
// TestPrint ensures that the Starlark print function calls
// Thread.Print, if provided.
func TestPrint(t *testing.T) {
const src = `
print("hello")
def f(): print("hello", "world", sep=", ")
f()
`
buf := new(bytes.Buffer)
print := func(thread *starlark.Thread, msg string) {
caller := thread.CallFrame(1)
fmt.Fprintf(buf, "%s: %s: %s\n", caller.Pos, caller.Name, msg)
}
thread := &starlark.Thread{Print: print}
if _, err := starlark.ExecFile(thread, "foo.star", src, nil); err != nil {
t.Fatal(err)
}
want := "foo.star:2:6: <toplevel>: hello\n" +
"foo.star:3:15: f: hello, world\n"
if got := buf.String(); got != want {
t.Errorf("output was %s, want %s", got, want)
}
}
func reportEvalError(tb testing.TB, err error) {
if err, ok := err.(*starlark.EvalError); ok {
tb.Fatal(err.Backtrace())
}
tb.Fatal(err)
}
// TestInt exercises the Int.Int64 and Int.Uint64 methods.
// If we can move their logic into math/big, delete this test.
func TestInt(t *testing.T) {
one := starlark.MakeInt(1)
for _, test := range []struct {
i starlark.Int
wantInt64 string
wantUint64 string
}{
{starlark.MakeInt64(math.MinInt64).Sub(one), "error", "error"},
{starlark.MakeInt64(math.MinInt64), "-9223372036854775808", "error"},
{starlark.MakeInt64(-1), "-1", "error"},
{starlark.MakeInt64(0), "0", "0"},
{starlark.MakeInt64(1), "1", "1"},
{starlark.MakeInt64(math.MaxInt64), "9223372036854775807", "9223372036854775807"},
{starlark.MakeUint64(math.MaxUint64), "error", "18446744073709551615"},
{starlark.MakeUint64(math.MaxUint64).Add(one), "error", "error"},
} {
gotInt64, gotUint64 := "error", "error"
if i, ok := test.i.Int64(); ok {
gotInt64 = fmt.Sprint(i)
}
if u, ok := test.i.Uint64(); ok {
gotUint64 = fmt.Sprint(u)
}
if gotInt64 != test.wantInt64 {
t.Errorf("(%s).Int64() = %s, want %s", test.i, gotInt64, test.wantInt64)
}
if gotUint64 != test.wantUint64 {
t.Errorf("(%s).Uint64() = %s, want %s", test.i, gotUint64, test.wantUint64)
}
}
}
func backtrace(t *testing.T, err error) string {
switch err := err.(type) {
case *starlark.EvalError:
return err.Backtrace()
case nil:
t.Fatalf("ExecFile succeeded unexpectedly")
default:
t.Fatalf("ExecFile failed with %v, wanted *EvalError", err)
}
panic("unreachable")
}
func TestBacktrace(t *testing.T) {
// This test ensures continuity of the stack of active Starlark
// functions, including propagation through built-ins such as 'min'.
const src = `
def f(x): return 1//x
def g(x): return f(x)
def h(): return min([1, 2, 0], key=g)
def i(): return h()
i()
`
thread := new(starlark.Thread)
_, err := starlark.ExecFile(thread, "crash.star", src, nil)
const want = `Traceback (most recent call last):
crash.star:6:2: in <toplevel>
crash.star:5:18: in i
crash.star:4:20: in h
<builtin>: in min
crash.star:3:19: in g
crash.star:2:19: in f
Error: floored division by zero`
if got := backtrace(t, err); got != want {
t.Errorf("error was %s, want %s", got, want)
}
// Additionally, ensure that errors originating in
// Starlark and/or Go each have an accurate frame.
// The topmost frame, if built-in, is not shown,
// but the name of the built-in function is shown
// as "Error in fn: ...".
//
// This program fails in Starlark (f) if x==0,
// or in Go (string.join) if x is non-zero.
const src2 = `
def f(): ''.join([1//i])
f()
`
for i, want := range []string{
0: `Traceback (most recent call last):
crash.star:3:2: in <toplevel>
crash.star:2:20: in f
Error: floored division by zero`,
1: `Traceback (most recent call last):
crash.star:3:2: in <toplevel>
crash.star:2:17: in f
Error in join: join: in list, want string, got int`,
} {
globals := starlark.StringDict{"i": starlark.MakeInt(i)}
_, err := starlark.ExecFile(thread, "crash.star", src2, globals)
if got := backtrace(t, err); got != want {
t.Errorf("error was %s, want %s", got, want)
}
}
}
func TestLoadBacktrace(t *testing.T) {
// This test ensures that load() does NOT preserve stack traces,
// but that API callers can get them with Unwrap().
// For discussion, see:
// https://github.com/google/starlark-go/pull/244
const src = `
load('crash.star', 'x')
`
const loadedSrc = `
def f(x):
return 1 // x
f(0)
`
thread := new(starlark.Thread)
thread.Load = func(t *starlark.Thread, module string) (starlark.StringDict, error) {
return starlark.ExecFile(new(starlark.Thread), module, loadedSrc, nil)
}
_, err := starlark.ExecFile(thread, "root.star", src, nil)
const want = `Traceback (most recent call last):
root.star:2:1: in <toplevel>
Error: cannot load crash.star: floored division by zero`
if got := backtrace(t, err); got != want {
t.Errorf("error was %s, want %s", got, want)
}
unwrapEvalError := func(err error) *starlark.EvalError {
var result *starlark.EvalError
for {
if evalErr, ok := err.(*starlark.EvalError); ok {
result = evalErr
}
// TODO: use errors.Unwrap when go >=1.13 is everywhere.
wrapper, isWrapper := err.(Wrapper)
if !isWrapper {
break
}
err = wrapper.Unwrap()
}
return result
}
unwrappedErr := unwrapEvalError(err)
const wantUnwrapped = `Traceback (most recent call last):
crash.star:5:2: in <toplevel>
crash.star:3:12: in f
Error: floored division by zero`
if got := backtrace(t, unwrappedErr); got != wantUnwrapped {
t.Errorf("error was %s, want %s", got, wantUnwrapped)
}
}
// TestRepeatedExec parses and resolves a file syntax tree once then
// executes it repeatedly with different values of its predeclared variables.
func TestRepeatedExec(t *testing.T) {
predeclared := starlark.StringDict{"x": starlark.None}
_, prog, err := starlark.SourceProgram("repeat.star", "y = 2 * x", predeclared.Has)
if err != nil {
t.Fatal(err)
}
for _, test := range []struct {
x, want starlark.Value
}{
{x: starlark.MakeInt(42), want: starlark.MakeInt(84)},
{x: starlark.String("mur"), want: starlark.String("murmur")},
{x: starlark.Tuple{starlark.None}, want: starlark.Tuple{starlark.None, starlark.None}},
} {
predeclared["x"] = test.x // update the values in dictionary
thread := new(starlark.Thread)
if globals, err := prog.Init(thread, predeclared); err != nil {
t.Errorf("x=%v: %v", test.x, err) // exec error
} else if eq, err := starlark.Equal(globals["y"], test.want); err != nil {
t.Errorf("x=%v: %v", test.x, err) // comparison error
} else if !eq {
t.Errorf("x=%v: got y=%v, want %v", test.x, globals["y"], test.want)
}
}
}
// TestEmptyFilePosition ensures that even Programs
// from empty files have a valid position.
func TestEmptyPosition(t *testing.T) {
var predeclared starlark.StringDict
for _, content := range []string{"", "empty = False"} {
_, prog, err := starlark.SourceProgram("hello.star", content, predeclared.Has)
if err != nil {
t.Fatal(err)
}
if got, want := prog.Filename(), "hello.star"; got != want {
t.Errorf("Program.Filename() = %q, want %q", got, want)
}
}
}
// TestUnpackUserDefined tests that user-defined
// implementations of starlark.Value may be unpacked.
func TestUnpackUserDefined(t *testing.T) {
// success
want := new(hasfields)
var x *hasfields
if err := starlark.UnpackArgs("unpack", starlark.Tuple{want}, nil, "x", &x); err != nil {
t.Errorf("UnpackArgs failed: %v", err)
}
if x != want {
t.Errorf("for x, got %v, want %v", x, want)
}
// failure
err := starlark.UnpackArgs("unpack", starlark.Tuple{starlark.MakeInt(42)}, nil, "x", &x)
if want := "unpack: for parameter x: got int, want hasfields"; fmt.Sprint(err) != want {
t.Errorf("unpack args error = %q, want %q", err, want)
}
}
type optionalStringUnpacker struct {
str string
isSet bool
}
func (o *optionalStringUnpacker) Unpack(v starlark.Value) error {
s, ok := starlark.AsString(v)
if !ok {
return fmt.Errorf("got %s, want string", v.Type())
}
o.str = s
o.isSet = ok
return nil
}
func TestUnpackCustomUnpacker(t *testing.T) {
a := optionalStringUnpacker{}
wantA := optionalStringUnpacker{str: "a", isSet: true}
b := optionalStringUnpacker{str: "b"}
wantB := optionalStringUnpacker{str: "b"}
// Success
if err := starlark.UnpackArgs("unpack", starlark.Tuple{starlark.String("a")}, nil, "a?", &a, "b?", &b); err != nil {
t.Errorf("UnpackArgs failed: %v", err)
}
if a != wantA {
t.Errorf("for a, got %v, want %v", a, wantA)
}
if b != wantB {
t.Errorf("for b, got %v, want %v", b, wantB)
}
// failure
err := starlark.UnpackArgs("unpack", starlark.Tuple{starlark.MakeInt(42)}, nil, "a", &a)
if want := "unpack: for parameter a: got int, want string"; fmt.Sprint(err) != want {
t.Errorf("unpack args error = %q, want %q", err, want)
}
}
func TestAsInt(t *testing.T) {
for _, test := range []struct {
val starlark.Value
ptr interface{}
want string
}{
{starlark.MakeInt(42), new(int32), "42"},
{starlark.MakeInt(-1), new(int32), "-1"},
// Use Lsh not 1<<40 as the latter exceeds int if GOARCH=386.
{starlark.MakeInt(1).Lsh(40), new(int32), "1099511627776 out of range (want value in signed 32-bit range)"},
{starlark.MakeInt(-1).Lsh(40), new(int32), "-1099511627776 out of range (want value in signed 32-bit range)"},
{starlark.MakeInt(42), new(uint16), "42"},
{starlark.MakeInt(0xffff), new(uint16), "65535"},
{starlark.MakeInt(0x10000), new(uint16), "65536 out of range (want value in unsigned 16-bit range)"},
{starlark.MakeInt(-1), new(uint16), "-1 out of range (want value in unsigned 16-bit range)"},
} {
var got string
if err := starlark.AsInt(test.val, test.ptr); err != nil {
got = err.Error()
} else {
got = fmt.Sprint(reflect.ValueOf(test.ptr).Elem().Interface())
}
if got != test.want {
t.Errorf("AsInt(%s, %T): got %q, want %q", test.val, test.ptr, got, test.want)
}
}
}
func TestDocstring(t *testing.T) {
globals, _ := starlark.ExecFile(&starlark.Thread{}, "doc.star", `
def somefunc():
"somefunc doc"
return 0
`, nil)
if globals["somefunc"].(*starlark.Function).Doc() != "somefunc doc" {
t.Fatal("docstring not found")
}
}
func TestFrameLocals(t *testing.T) {
// trace prints a nice stack trace including argument
// values of calls to Starlark functions.
trace := func(thread *starlark.Thread) string {
buf := new(bytes.Buffer)
for i := 0; i < thread.CallStackDepth(); i++ {
fr := thread.DebugFrame(i)
fmt.Fprintf(buf, "%s(", fr.Callable().Name())
if fn, ok := fr.Callable().(*starlark.Function); ok {
for i := 0; i < fn.NumParams(); i++ {
if i > 0 {
buf.WriteString(", ")
}
name, _ := fn.Param(i)
fmt.Fprintf(buf, "%s=%s", name, fr.Local(i))
}
} else {
buf.WriteString("...") // a built-in function
}
buf.WriteString(")\n")
}
return buf.String()
}
var got string
builtin := func(thread *starlark.Thread, _ *starlark.Builtin, _ starlark.Tuple, _ []starlark.Tuple) (starlark.Value, error) {
got = trace(thread)
return starlark.None, nil
}
predeclared := starlark.StringDict{
"builtin": starlark.NewBuiltin("builtin", builtin),
}
_, err := starlark.ExecFile(&starlark.Thread{}, "foo.star", `
def f(x, y): builtin()
def g(z): f(z, z*z)
g(7)
`, predeclared)
if err != nil {
t.Errorf("ExecFile failed: %v", err)
}
var want = `
builtin(...)
f(x=7, y=49)
g(z=7)
<toplevel>()
`[1:]
if got != want {
t.Errorf("got <<%s>>, want <<%s>>", got, want)
}
}
type badType string
func (b *badType) String() string { return "badType" }
func (b *badType) Type() string { return "badType:" + string(*b) } // panics if b==nil
func (b *badType) Truth() starlark.Bool { return true }
func (b *badType) Hash() (uint32, error) { return 0, nil }
func (b *badType) Freeze() {}
var _ starlark.Value = new(badType)
// TestUnpackErrorBadType verifies that the Unpack functions fail
// gracefully when a parameter's default value's Type method panics.
func TestUnpackErrorBadType(t *testing.T) {
for _, test := range []struct {
x *badType
want string
}{
{new(badType), "got NoneType, want badType"}, // Starlark type name
{nil, "got NoneType, want *starlark_test.badType"}, // Go type name
} {
err := starlark.UnpackArgs("f", starlark.Tuple{starlark.None}, nil, "x", &test.x)
if err == nil {
t.Errorf("UnpackArgs succeeded unexpectedly")
continue
}
if !strings.Contains(err.Error(), test.want) {
t.Errorf("UnpackArgs error %q does not contain %q", err, test.want)
}
}
}
// Regression test for github.com/google/starlark-go/issues/233.
func TestREPLChunk(t *testing.T) {
thread := new(starlark.Thread)
globals := make(starlark.StringDict)
exec := func(src string) {
f, err := syntax.Parse("<repl>", src, 0)
if err != nil {
t.Fatal(err)
}
if err := starlark.ExecREPLChunk(f, thread, globals); err != nil {
t.Fatal(err)
}
}
exec("x = 0; y = 0")
if got, want := fmt.Sprintf("%v %v", globals["x"], globals["y"]), "0 0"; got != want {
t.Fatalf("chunk1: got %s, want %s", got, want)
}
exec("x += 1; y = y + 1")
if got, want := fmt.Sprintf("%v %v", globals["x"], globals["y"]), "1 1"; got != want {
t.Fatalf("chunk2: got %s, want %s", got, want)
}
}
func TestCancel(t *testing.T) {
// A thread cancelled before it begins executes no code.
{
thread := new(starlark.Thread)
thread.Cancel("nope")
_, err := starlark.ExecFile(thread, "precancel.star", `x = 1//0`, nil)
if fmt.Sprint(err) != "Starlark computation cancelled: nope" {
t.Errorf("execution returned error %q, want cancellation", err)
}
// cancellation is sticky
_, err = starlark.ExecFile(thread, "precancel.star", `x = 1//0`, nil)
if fmt.Sprint(err) != "Starlark computation cancelled: nope" {
t.Errorf("execution returned error %q, want cancellation", err)
}
}
// A thread cancelled during a built-in executes no more code.
{
thread := new(starlark.Thread)
predeclared := starlark.StringDict{
"stopit": starlark.NewBuiltin("stopit", func(thread *starlark.Thread, b *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
thread.Cancel(fmt.Sprint(args[0]))
return starlark.None, nil
}),
}
_, err := starlark.ExecFile(thread, "stopit.star", `msg = 'nope'; stopit(msg); x = 1//0`, predeclared)
if fmt.Sprint(err) != `Starlark computation cancelled: "nope"` {
t.Errorf("execution returned error %q, want cancellation", err)
}
}
}
func TestExecutionSteps(t *testing.T) {
// A Thread records the number of computation steps.
thread := new(starlark.Thread)
countSteps := func(n int) (uint64, error) {
predeclared := starlark.StringDict{"n": starlark.MakeInt(n)}
steps0 := thread.ExecutionSteps()
_, err := starlark.ExecFile(thread, "steps.star", `squares = [x*x for x in range(n)]`, predeclared)
return thread.ExecutionSteps() - steps0, err
}
steps100, err := countSteps(1000)
if err != nil {
t.Errorf("execution failed: %v", err)
}
steps10000, err := countSteps(100000)
if err != nil {
t.Errorf("execution failed: %v", err)
}
if ratio := float64(steps10000) / float64(steps100); ratio < 99 || ratio > 101 {
t.Errorf("computation steps did not increase linearly: f(100)=%d, f(10000)=%d, ratio=%g, want ~100", steps100, steps10000, ratio)
}
// Exceeding the step limit causes cancellation.
thread.SetMaxExecutionSteps(1000)
_, err = countSteps(1000)
if fmt.Sprint(err) != "Starlark computation cancelled: too many steps" {
t.Errorf("execution returned error %q, want cancellation", err)
}
}
// TestDeps fails if the interpreter proper (not the REPL, etc) sprouts new external dependencies.
// We may expand the list of permitted dependencies, but should do so deliberately, not casually.
func TestDeps(t *testing.T) {
cmd := exec.Command("go", "list", "-deps")
out, err := cmd.Output()
if err != nil {
t.Skipf("'go list' failed: %s", err)
}
for _, pkg := range strings.Split(string(out), "\n") {
// Does pkg have form "domain.name/dir"?
slash := strings.IndexByte(pkg, '/')
dot := strings.IndexByte(pkg, '.')
if 0 < dot && dot < slash {
if strings.HasPrefix(pkg, "go.starlark.net/") ||
strings.HasPrefix(pkg, "golang.org/x/sys/") {
continue // permitted dependencies
}
t.Errorf("new interpreter dependency: %s", pkg)
}
}
}