fix: range over channels returned by binary calls

* fix: composite map assign

* reword comment

Co-authored-by: Marc Vertes <mvertes@free.fr>

.golangci.toml

@@ -37,6 +37,7 @@
     "funlen",
     "gocognit",
     "stylecheck",
+    "gomnd",
   ]
 
 [issues]

.travis.yml

@@ -19,13 +19,14 @@ cache:
 matrix:
   fast_finish: true
   include:
-    - go: 1.12.x
     - go: 1.13.x
+    - go: 1.14.x
       env: STABLE=true
 
 env:
   global:
     - GO111MODULE=on
+    - CI=1
 
 go_import_path: github.com/containous/yaegi
 
@@ -39,7 +40,7 @@ install:
   - go mod download
 
 before_script:
-  - rm -f interp/op.go interp/interp_test.go
+  - rm -f interp/op.go
   - make generate
   - git update-index -q --refresh
   - CHANGED=$(git diff-index --name-only HEAD --)

CONTRIBUTING.md

@@ -13,7 +13,12 @@ discussions.
 Once the proposal is approved, a Pull Request can be opened. If you want
 to provide early visibility to reviewers, create a [Draft Pull Request].
 
+We will also require you to sign the [Containous Contributor License Agreement]
+after you submit your first pull request to this project. The link to sign the
+agreement will be presented to you in the web interface of the pull request.
+
 [Issues]: https://github.com/containous/yaegi/issues
 [Pull Requests]: https://github.com/containous/yaegi/issues
 [Feature Request]: https://github.com/containous/yaegi/issues/new?template=feature_request.md
 [Draft Pull Request]: https://github.blog/2019-02-14-introducing-draft-pull-requests/
+[Containous Contributor License Agreement]: https://cla-assistant.io/containous/yaegi

README.md

@@ -18,7 +18,7 @@ It powers executable Go scripts and plugins, in embedded interpreters or interac
 * Works everywhere Go works
 * All Go & runtime resources accessible from script (with control)
 * Security: `unsafe` and `syscall` packages neither used nor exported by default
-* Support Go 1.12 and Go 1.13 (the latest 2 major releases)
+* Support Go 1.13 and Go 1.14 (the latest 2 major releases)
 
 ## Install
 
@@ -129,6 +129,24 @@ $ yaegi cmd/yaegi/yaegi.go
 >
 ```
 
+Or for Go scripting in the shebang line:
+
+```console
+$ cat /tmp/test
+#!/usr/bin/env yaegi
+package main
+
+import "fmt"
+
+func main() {
+	fmt.Println("test")
+}
+$ ls -la /tmp/test
+-rwxr-xr-x 1 dow184 dow184 93 Jan  6 13:38 /tmp/test
+$ /tmp/test
+test
+```
+
 ## Documentation
 
 Documentation about Yaegi commands and libraries can be found at usual [godoc.org][docs].

_test/a40.go

@@ -0,0 +1,23 @@
+package main
+
+import "fmt"
+
+type rule uint8
+
+const (
+	r0 rule = iota
+	r1
+	r2
+)
+
+var a = [...]int{
+	r0: 1,
+	r1: 12,
+}
+
+func main() {
+	fmt.Println(a)
+}
+
+// Output:
+// [1 12]

_test/a41.go

@@ -0,0 +1,10 @@
+package main
+
+var a = [...]bool{true, true}
+
+func main() {
+	println(a[0] && true)
+}
+
+// Output:
+// true

_test/add0.go

@@ -0,0 +1,9 @@
+package main
+
+func main() {
+	var a interface{} = 2 + 5
+	println(a.(int))
+}
+
+// Output:
+// 7

_test/add1.go

@@ -0,0 +1,10 @@
+package main
+
+func main() {
+	b := 2
+	var a interface{} = 5 + b
+	println(a.(int))
+}
+
+// Output:
+// 7

_test/add2.go

@@ -0,0 +1,12 @@
+package main
+
+type iface interface{}
+
+func main() {
+	b := 2
+	var a iface = 5 + b
+	println(a.(int))
+}
+
+// Output:
+// 7

_test/and3.go

@@ -0,0 +1,10 @@
+package main
+
+var a = true && true
+
+func main() {
+	println(a)
+}
+
+// Output:
+// true

_test/append0.go

@@ -0,0 +1,14 @@
+package main
+
+import "fmt"
+
+func f(a []int, b int) interface{} { return append(a, b) }
+
+func main() {
+	a := []int{1, 2}
+	r := f(a, 3)
+	fmt.Println(r.([]int))
+}
+
+// Output:
+// [1 2 3]

_test/assign1.go

@@ -9,5 +9,5 @@ func main() {
 	fmt.Println(buf)
 }
 
-// Output
+// Output:
 // []

_test/assign11.go

@@ -0,0 +1,10 @@
+package main
+
+import "fmt"
+
+func main() {
+	_, _, _ = fmt.Println("test")
+}
+
+// Error:
+// 6:2: assignment mismatch: 3 variables but fmt.Println returns 2 values

_test/assign12.go

@@ -0,0 +1,11 @@
+package main
+
+import "fmt"
+
+func main() {
+	a, b, c := fmt.Println("test")
+	println(a, b, c)
+}
+
+// Error:
+// 6:2: assignment mismatch: 3 variables but fmt.Println returns 2 values

_test/b1/foo/foo.go

@@ -0,0 +1,7 @@
+package foo
+
+import bar "github.com/containous/yaegi/_test/b2/foo"
+
+var Desc = "in b1/foo"
+
+var Desc2 = Desc + bar.Desc

_test/b2/foo/foo.go

@@ -0,0 +1,3 @@
+package foo
+
+var Desc = "in b2/foo"

_test/bad0.go

@@ -1,4 +1,4 @@
 println("Hello")
 
 // Error:
-// _test/bad0.go:1:1: expected 'package', found println
+// 1:1: expected 'package', found println

_test/baz-bat/baz-bat.go

@@ -0,0 +1,3 @@
+package baz
+
+var Name = "baz-bat"

_test/bin2.go

@@ -0,0 +1,13 @@
+package main
+
+import (
+	"fmt"
+	"math"
+)
+
+func main() {
+	fmt.Println(math.Abs(-5))
+}
+
+// Output:
+// 5

_test/bin3.go

@@ -0,0 +1,12 @@
+package main
+
+import "fmt"
+
+func main() {
+	str := "part1"
+	str += fmt.Sprintf("%s", "part2")
+	fmt.Println(str)
+}
+
+// Output:
+// part1part2

_test/bin4.go

@@ -0,0 +1,18 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+)
+
+func Bar(s string) bool {
+	a := strings.HasPrefix("fas", "f")
+	b := strings.HasPrefix("aaaaa", "a")
+	a_and_b := strings.HasPrefix("fas", "f") && strings.HasPrefix("aaaaa", "a")
+	fmt.Println(a, b, a && b, a_and_b)
+	return a && b
+}
+
+func main() {
+	println(Bar("kung"))
+}

_test/bin5.go

@@ -0,0 +1,15 @@
+package main
+
+import (
+	"fmt"
+	"net"
+)
+
+func main() {
+	addr := net.TCPAddr{IP: net.IPv4(1, 1, 1, 1), Port: 80}
+	var s fmt.Stringer = &addr
+	fmt.Println(s.String())
+}
+
+// Output:
+// 1.1.1.1:80

_test/cap0.go

@@ -0,0 +1,13 @@
+package main
+
+func f(a []int) interface{} {
+	return cap(a)
+}
+
+func main() {
+	a := []int{1, 2}
+	println(f(a).(int))
+}
+
+// Output:
+// 2

_test/chan8.go

@@ -0,0 +1,12 @@
+package main
+
+func main() {
+	messages := make(chan bool)
+
+	go func() { messages <- true }()
+
+	println(<-messages && true)
+}
+
+// Output:
+// true

_test/chan9.go

@@ -0,0 +1,20 @@
+package main
+
+type Channel chan string
+
+type T struct {
+	Channel
+}
+
+func send(c Channel) { c <- "ping" }
+
+func main() {
+	t := &T{}
+	t.Channel = make(Channel)
+	go send(t.Channel)
+	msg := <-t.Channel
+	println(msg)
+}
+
+// Output:
+// ping

_test/cli2.go

@@ -0,0 +1,59 @@
+package main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net"
+	"net/http"
+)
+
+type T struct {
+	ln net.Listener
+}
+
+func (t *T) Close() {
+	t.ln.Close()
+}
+
+func client(uri string) {
+	resp, err := http.Get(uri)
+	if err != nil {
+		log.Fatal(err)
+	}
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Println(string(body))
+}
+
+func server(ln net.Listener, ready chan bool) {
+	http.HandleFunc("/hello", func(w http.ResponseWriter, r *http.Request) {
+		var r1 *http.Request = r
+		fmt.Fprintln(w, "Welcome to my website!", r1.RequestURI)
+	})
+
+	go http.Serve(ln, nil)
+	ready <- true
+}
+
+func main() {
+	ln, err := net.Listen("tcp", "localhost:0")
+	t := &T{ln}
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer t.Close()
+	//	defer ln.Close()
+
+	ready := make(chan bool)
+	go server(ln, ready)
+	<-ready
+
+	client(fmt.Sprintf("http://%s/hello", ln.Addr().String()))
+	http.DefaultServeMux = &http.ServeMux{}
+}
+
+// Output:
+// Welcome to my website! /hello

_test/comp1.go

@@ -0,0 +1,9 @@
+package main
+
+func main() {
+	var a interface{} = 1 < 2
+	println(a.(bool))
+}
+
+// Output:
+// true

_test/complex3.go

@@ -7,5 +7,5 @@ func main() {
 	fmt.Printf("%T %v\n", s, s)
 }
 
-// Output
+// Output:
 // int 2

_test/complex4.go

@@ -0,0 +1,13 @@
+package main
+
+import "fmt"
+
+func f(a, b float64) interface{} { return complex(a, b) }
+
+func main() {
+	a := f(3, 2)
+	fmt.Println(a.(complex128))
+}
+
+// Output:
+// (3+2i)

_test/composite10.go

@@ -0,0 +1,14 @@
+package main
+
+import "fmt"
+
+func main() {
+	a := []map[int]int{make(map[int]int)}
+
+	for _, b := range a {
+		fmt.Println(b)
+	}
+}
+
+// Output:
+// map[]

_test/composite5.go

@@ -0,0 +1,16 @@
+package main
+
+import "fmt"
+
+type T struct {
+	m uint16
+}
+
+var t = T{1<<2 | 1<<3}
+
+func main() {
+	fmt.Println(t)
+}
+
+// Output:
+// {12}

_test/composite6.go

@@ -0,0 +1,20 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/containous/yaegi/_test/ct1"
+)
+
+type T struct {
+	m uint16
+}
+
+var t = T{1 << ct1.R}
+
+func main() {
+	fmt.Println(t)
+}
+
+// Output:
+// {2}

_test/composite7.go

@@ -0,0 +1,20 @@
+package main
+
+type T struct {
+	name string
+}
+
+var tab = []*T{{
+	name: "foo",
+}, {
+	name: "bar",
+}}
+
+func main() {
+	println(len(tab))
+	println(tab[0].name)
+}
+
+// Output:
+// 2
+// foo

_test/composite8.go

@@ -0,0 +1,16 @@
+package main
+
+type T struct{ I int }
+
+func main() {
+	t := []*T{}
+	s := []int{1, 2}
+	for _, e := range s {
+		x := &T{e}
+		t = append(t, x)
+	}
+	println(t[0].I, t[1].I)
+}
+
+// Output:
+// 1 2

_test/composite9.go

@@ -0,0 +1,14 @@
+package main
+
+import "fmt"
+
+func main() {
+	a := [][]int{make([]int,0)}
+
+	for _, b := range a {
+		fmt.Println(b)
+	}
+}
+
+// Output:
+// []

_test/const10.go

@@ -0,0 +1,17 @@
+package main
+
+const (
+	a = 2
+	b = c + d
+	c = a + d
+	d = e + f
+	e = 3
+	f = 4
+)
+
+func main() {
+	println(b)
+}
+
+// Output:
+// 16

_test/const11.go

@@ -0,0 +1,13 @@
+package main
+
+func main() {
+	const (
+		x = 2 * iota
+		dim
+	)
+	var t [dim * 2]int
+	println(t[0], len(t))
+}
+
+// Output:
+// 0 4

_test/const12.go

@@ -0,0 +1,17 @@
+package main
+
+type Kind int
+
+const (
+	None Kind = 0
+	Left Kind = 1 << iota
+	Right
+	Both Kind = Left | Right
+)
+
+func main() {
+	println(None, Left, Right, Both)
+}
+
+// Output:
+// 0 2 4 6

_test/const13.go

@@ -0,0 +1,16 @@
+package main
+
+import (
+	"fmt"
+)
+
+func main() {
+	const tooBig = 1267650600228229401496703205376
+	const huge = 1 << 100
+	const large = huge >> 38
+
+	fmt.Println(large)
+}
+
+// Output:
+// 4611686018427387904

_test/const6.go

@@ -0,0 +1,22 @@
+package main
+
+const (
+	maxNonStarters = 30
+	maxBufferSize  = maxNonStarters + 2
+)
+
+type reorderBuffer struct {
+	rune [maxBufferSize]Properties
+}
+
+type Properties struct {
+	pos  uint8
+	size uint8
+}
+
+func main() {
+	println(len(reorderBuffer{}.rune))
+}
+
+// Output:
+// 32

_test/const7.go

@@ -0,0 +1,19 @@
+package main
+
+import "fmt"
+
+const (
+	a = iota
+	b
+	c
+	d
+)
+
+type T [c]int
+
+func main() {
+	fmt.Println(T{})
+}
+
+// Output:
+// [0 0]

_test/const8.go

@@ -0,0 +1,15 @@
+package main
+
+const (
+	a = 2
+	b = c + d
+	c = 4
+	d = 5
+)
+
+func main() {
+	println(a, b, c, d)
+}
+
+// Output:
+// 2 9 4 5

_test/const9.go

@@ -0,0 +1,17 @@
+package main
+
+const (
+	a = 2
+	b = c + d
+	c = a + d
+	d = e + f
+	e = b + 2
+	f = 4
+)
+
+func main() {
+	println(b)
+}
+
+// Error:
+// 5:2: constant definition loop

_test/copy2.go

@@ -0,0 +1,16 @@
+package main
+
+import "fmt"
+
+func f(a, b []int) interface{} { return copy(a, b) }
+
+func main() {
+	a := []int{10, 20, 30}
+	b := [4]int{}
+	c := b[:]
+	r := f(c, a)
+	fmt.Println(r.(int))
+}
+
+// Output:
+// 3

_test/ct1/ct1.go

@@ -0,0 +1,9 @@
+package ct1
+
+type Class uint
+
+const (
+	L Class = iota
+	R
+	AL
+)

_test/defer4.go

@@ -0,0 +1,23 @@
+package main
+
+import "sync"
+
+type T struct {
+	mu   sync.RWMutex
+	name string
+}
+
+func (t *T) get() string {
+	t.mu.RLock()
+	defer t.mu.RUnlock()
+	return t.name
+}
+
+var d = T{name: "test"}
+
+func main() {
+	println(d.get())
+}
+
+// Output:
+// test

_test/for10.go

@@ -0,0 +1,13 @@
+package main
+
+func main() {
+	for a := 0; false; {
+		println("nok", a)
+		a++
+		break
+	}
+	println("bye")
+}
+
+// Output:
+// bye

_test/for11.go

@@ -0,0 +1,14 @@
+package main
+
+func main() {
+	a := 0
+	for ; true; a++ {
+		println("nok", a)
+		break
+	}
+	println("bye", a)
+}
+
+// Output:
+// nok 0
+// bye 0

_test/for12.go

@@ -0,0 +1,12 @@
+package main
+
+func main() {
+	for a := 0; false; a++ {
+		println("nok", a)
+		break
+	}
+	println("bye")
+}
+
+// Output:
+// bye

_test/for13.go

@@ -0,0 +1,13 @@
+package main
+
+func main() {
+	a := 0
+	for ; false; a++ {
+		println("nok", a)
+		break
+	}
+	println("bye", a)
+}
+
+// Output:
+// bye 0

_test/for14.go

@@ -0,0 +1,16 @@
+package main
+
+func main() {
+	for a := 0; true; a++ {
+		println(a)
+		if a > 0 {
+			break
+		}
+	}
+	println("bye")
+}
+
+// Output:
+// 0
+// 1
+// bye

_test/for8.go

@@ -0,0 +1,18 @@
+package main
+
+func main() {
+	for i := 0; i < 4; i++ {
+		for {
+			break
+		}
+		if i == 1 {
+			continue
+		}
+		println(i)
+	}
+}
+
+// Output:
+// 0
+// 2
+// 3

_test/for9.go

@@ -0,0 +1,12 @@
+package main
+
+func main() {
+	for false {
+		println("nok")
+		break
+	}
+	println("bye")
+}
+
+// Output:
+// bye

_test/fun11.go

@@ -0,0 +1,12 @@
+package main
+
+var f F
+
+type F func(int)
+
+func main() {
+	println("ok")
+}
+
+// Output:
+// ok

_test/fun12.go

@@ -0,0 +1,12 @@
+package main
+
+func use(interface{}) {}
+
+func main() {
+	z := map[string]interface{}{"a": 5}
+	use(z)
+	println("bye")
+}
+
+// Output:
+// bye

_test/fun13.go

@@ -0,0 +1,19 @@
+package main
+
+import "fmt"
+
+type T struct{}
+
+func newT() (T, error) { return T{}, nil }
+
+func main() {
+	var (
+		i   interface{}
+		err error
+	)
+	i, err = newT()
+	fmt.Println(i, err)
+}
+
+// Output:
+// {} <nil>

_test/fun14.go

@@ -0,0 +1,13 @@
+package main
+
+func f() (bool, int) { return true, 2 }
+
+func g() (bool, int) { return f() }
+
+func main() {
+	b, i := g()
+	println(b, i)
+}
+
+// Output:
+// true 2

_test/fun15.go

@@ -0,0 +1,11 @@
+package main
+
+func f1(a int) interface{} { return a + 1 }
+
+func main() {
+	c := f1(3)
+	println(c.(int))
+}
+
+// Output:
+// 4

_test/fun16.go

@@ -0,0 +1,13 @@
+package main
+
+func f1(a int) int { return a + 1 }
+
+func f2(a int) interface{} { return f1(a) }
+
+func main() {
+	c := f2(3)
+	println(c.(int))
+}
+
+// Output:
+// 4

_test/fun17.go

@@ -0,0 +1,13 @@
+package main
+
+func f1(a int) interface{} { return a + 1 }
+
+func f2(a int) interface{} { return f1(a) }
+
+func main() {
+	c := f2(3)
+	println(c.(int))
+}
+
+// Output:
+// 4

_test/fun18.go

@@ -0,0 +1,12 @@
+package main
+
+var m = map[string]int{"foo": 1, "bar": 2}
+
+func f(s string) interface{} { return m[s] }
+
+func main() {
+	println(f("foo").(int))
+}
+
+// Output:
+// 1

_test/fun19.go

@@ -0,0 +1,17 @@
+package main
+
+import (
+	"fmt"
+)
+
+func foo() ([]string, error) {
+	return nil, fmt.Errorf("bar")
+}
+
+func main() {
+	a, b := foo()
+	fmt.Println(a, b)
+}
+
+// Output:
+// [] bar

_test/fun20.go

@@ -0,0 +1,19 @@
+package main
+
+import "fmt"
+
+var myerr error = fmt.Errorf("bar")
+
+func ferr() error { return myerr }
+
+func foo() ([]string, error) {
+	return nil, ferr()
+}
+
+func main() {
+	a, b := foo()
+	fmt.Println(a, b)
+}
+
+// Output:
+// [] bar

_test/fun21.go

@@ -0,0 +1,12 @@
+package main
+
+func Bar() string {
+	return
+}
+
+func main() {
+	println(Bar())
+}
+
+// Error:
+// 4:2: not enough arguments to return

_test/fun22.go

@@ -0,0 +1,10 @@
+package main
+
+import "time"
+
+func main() {
+	time.Date()
+}
+
+// Error:
+// 6:2: not enough arguments in call to time.Date

_test/if3.go

@@ -0,0 +1,17 @@
+package main
+
+func main() {
+	a := 0
+	if false {
+		println("false")
+		a = 1
+	} else {
+		println("true")
+		a = -1
+	}
+	println(a)
+}
+
+// Output:
+// true
+// -1

_test/if4.go

@@ -0,0 +1,19 @@
+package main
+
+const bad = false
+
+func main() {
+	a := 0
+	if bad {
+		println("false")
+		a = 1
+	} else {
+		println("true")
+		a = -1
+	}
+	println(a)
+}
+
+// Output:
+// true
+// -1

_test/if5.go

@@ -0,0 +1,12 @@
+package main
+
+func main() {
+	if true {
+		println("ok")
+	}
+	println("bye")
+}
+
+// Output:
+// ok
+// bye

_test/if6.go

@@ -0,0 +1,11 @@
+package main
+
+func main() {
+	if false {
+		println("nok")
+	}
+	println("bye")
+}
+
+// Output:
+// bye

_test/if7.go

@@ -0,0 +1,15 @@
+package main
+
+func main() {
+	a := 0
+	b := false
+	if (b) {
+		a = 1
+	} else {
+		a = -1
+	}
+	println(a)
+}
+
+// Output:
+// -1

_test/imag0.go

@@ -0,0 +1,14 @@
+package main
+
+import "fmt"
+
+func f(c complex128) interface{} { return imag(c) }
+
+func main() {
+	c := complex(3, 2)
+	a := f(c)
+	fmt.Println(a.(float64))
+}
+
+// Output:
+// 2

_test/import8.go

@@ -0,0 +1,10 @@
+package main
+
+import "github.com/containous/yaegi/_test/b1/foo"
+
+func main() {
+	println(foo.Desc)
+}
+
+// Output:
+// in b1/foo

_test/import9.go

@@ -0,0 +1,10 @@
+package main
+
+import "github.com/containous/yaegi/_test/baz-bat"
+
+func main() {
+	println(baz.Name)
+}
+
+// Output:
+// baz-bat

_test/interface19.go

@@ -0,0 +1,12 @@
+package main
+
+import "fmt"
+
+var I interface{}
+
+func main() {
+	fmt.Printf("%T %v\n", I, I)
+}
+
+// Output:
+// <nil> <nil>

_test/interface20.go

@@ -0,0 +1,12 @@
+package main
+
+import "fmt"
+
+func main() {
+	var a interface{}
+	a = string("A")
+	fmt.Println(a)
+}
+
+// Output:
+// A

_test/interface21.go

@@ -0,0 +1,12 @@
+package main
+
+import "fmt"
+
+func main() {
+	s := make([]interface{}, 1)
+	s[0] = 1
+	fmt.Println(s[0])
+}
+
+// Output:
+// 1

_test/interface22.go

@@ -0,0 +1,12 @@
+package main
+
+import "fmt"
+
+func main() {
+	s := make([]interface{}, 0)
+	s = append(s, 1)
+	fmt.Println(s[0])
+}
+
+// Output:
+// 1

_test/interface23.go

@@ -0,0 +1,12 @@
+package main
+
+import "fmt"
+
+func main() {
+	m := make(map[string]interface{})
+	m["A"] = string("A")
+	fmt.Println(m["A"])
+}
+
+// Output:
+// A

_test/interface24.go

@@ -0,0 +1,11 @@
+package main
+
+import "fmt"
+
+func main() {
+	m := make(map[string]interface{})
+	fmt.Println(m["B"])
+}
+
+// Output:
+// <nil>

_test/interface25.go

@@ -0,0 +1,14 @@
+package main
+
+import "fmt"
+
+func main() {
+	m := make(map[string]interface{})
+	m["A"] = 1
+	for _, v := range m {
+		fmt.Println(v)
+	}
+}
+
+// Output:
+// 1

_test/interface26.go

@@ -0,0 +1,14 @@
+package main
+
+import "fmt"
+
+func main() {
+	s := make([]interface{}, 0)
+	s = append(s, 1)
+	for _, v := range s {
+		fmt.Println(v)
+	}
+}
+
+// Output:
+// 1

_test/interface27.go

@@ -0,0 +1,12 @@
+package main
+
+import "fmt"
+
+var errs = map[int]error{0: nil}
+
+func main() {
+	fmt.Println(errs)
+}
+
+// Output:
+// map[0:<nil>]

_test/interface28.go

@@ -0,0 +1,12 @@
+package main
+
+import "fmt"
+
+var errs = []error{nil}
+
+func main() {
+	fmt.Println(errs)
+}
+
+// Output:
+// [<nil>]

_test/interface29.go

@@ -0,0 +1,9 @@
+package main
+
+func main() {
+	var a interface{}
+	println(a == nil)
+}
+
+// Output:
+// true

_test/interface30.go

@@ -0,0 +1,9 @@
+package main
+
+func main() {
+	var a interface{}
+	println(a != nil)
+}
+
+// Output:
+// false

_test/interface31.go

@@ -0,0 +1,11 @@
+package main
+
+import "fmt"
+
+func main() {
+	s := []interface{}{"test", 2}
+	fmt.Println(s[0], s[1])
+}
+
+// Output:
+// test 2

_test/interface32.go

@@ -0,0 +1,11 @@
+package main
+
+import "fmt"
+
+func main() {
+	s := [2]interface{}{"test", 2}
+	fmt.Println(s[0], s[1])
+}
+
+// Output:
+// test 2

_test/interface33.go

@@ -0,0 +1,11 @@
+package main
+
+import "fmt"
+
+func main() {
+	var a = map[string]interface{}{"test": "test"}
+	fmt.Println(a["test"])
+}
+
+// Output:
+// test

_test/interface34.go

@@ -0,0 +1,11 @@
+package main
+
+import "fmt"
+
+func main() {
+	s := [2]interface{}{1: "test", 0: 2}
+	fmt.Println(s[0], s[1])
+}
+
+// Output:
+// 2 test

_test/interface35.go

@@ -0,0 +1,15 @@
+package main
+
+import "fmt"
+
+type T struct {
+	I interface{}
+}
+
+func main() {
+	t := T{"test"}
+	fmt.Println(t)
+}
+
+// Output:
+// {test}

_test/interface36.go

@@ -0,0 +1,37 @@
+package main
+
+import "fmt"
+
+var (
+	t *S
+	_ I = t
+	_ J = t
+)
+
+type S struct {
+	Name string
+}
+
+func (s *S) F() int { return len(s.Name) }
+func (s *S) G() int { return s.F() }
+func (s *S) Ri() I  { return s }
+func (s *S) Rj() J  { return s }
+
+type J interface {
+	I
+	G() int
+	Rj() J
+}
+
+type I interface {
+	F() int
+	Ri() I
+}
+
+func main() {
+	var j J
+	fmt.Println(j)
+}
+
+// Output:
+// <nil>

_test/interface37.go

@@ -0,0 +1,23 @@
+package main
+
+type I interface {
+	A() string
+	B() string
+}
+
+type s struct{}
+
+func NewS() (I, error) {
+	return &s{}, nil
+}
+
+func (c *s) A() string { return "a" }
+func (c *s) B() string { return "b" }
+
+func main() {
+	s, _ := NewS()
+	println(s.A())
+}
+
+// Output:
+// a

_test/interface38.go

@@ -0,0 +1,19 @@
+package main
+
+import "fmt"
+
+type foo struct {
+	bar string
+}
+
+func (f foo) String() string {
+	return "Hello from " + f.bar
+}
+
+func main() {
+	var f fmt.Stringer = foo{bar: "bar"}
+	fmt.Println(f)
+}
+
+// Output:
+// Hello from bar

_test/interface39.go

@@ -0,0 +1,19 @@
+package main
+
+import "fmt"
+
+type foo struct {
+	bar string
+}
+
+func (f *foo) String() string {
+	return "Hello from " + f.bar
+}
+
+func main() {
+	var f fmt.Stringer = &foo{bar: "bar"}
+	fmt.Println(f)
+}
+
+// Output:
+// Hello from bar

_test/interface40.go

@@ -0,0 +1,23 @@
+package main
+
+import "fmt"
+
+type foo struct {
+	bar string
+}
+
+func (f foo) String() string {
+	return "Hello from " + f.bar
+}
+
+func Foo(s string) fmt.Stringer {
+	return foo{s}
+}
+
+func main() {
+	f := Foo("bar")
+	fmt.Println(f)
+}
+
+// Output:
+// Hello from bar

_test/interface41.go

@@ -0,0 +1,23 @@
+package main
+
+import "fmt"
+
+type foo struct {
+	bar string
+}
+
+func (f *foo) String() string {
+	return "Hello from " + f.bar
+}
+
+func Foo(s string) fmt.Stringer {
+	return &foo{s}
+}
+
+func main() {
+	f := Foo("bar")
+	fmt.Println(f)
+}
+
+// Output:
+// Hello from bar

_test/interface42.go

@@ -0,0 +1,12 @@
+package main
+
+import "fmt"
+
+func main() {
+	v := interface{}(0)
+
+	fmt.Println(v)
+}
+
+// Output:
+// 0

_test/interface43.go

@@ -0,0 +1,12 @@
+package main
+
+import "fmt"
+
+func main() {
+	v := interface{}(nil)
+
+	fmt.Println(v)
+}
+
+// Output:
+// <nil>

_test/issue-558.go

@@ -0,0 +1,55 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"log"
+	"strings"
+)
+
+type readAutoCloser struct {
+	r io.ReadCloser
+}
+
+func (a readAutoCloser) Read(b []byte) (n int, err error) {
+	if a.r == nil {
+		return 0, io.EOF
+	}
+	n, err = a.r.Read(b)
+	if err == io.EOF {
+		a.Close()
+	}
+	return n, err
+}
+
+func (a readAutoCloser) Close() error {
+	if a.r == nil {
+		return nil
+	}
+	return a.r.(io.Closer).Close()
+}
+
+type pipe struct {
+	Reader readAutoCloser
+}
+
+func newReadAutoCloser(r io.Reader) readAutoCloser {
+	if _, ok := r.(io.Closer); !ok {
+		return readAutoCloser{ioutil.NopCloser(r)}
+	}
+	return readAutoCloser{r.(io.ReadCloser)}
+}
+
+func main() {
+	p := &pipe{}
+	p.Reader = newReadAutoCloser(strings.NewReader("test"))
+	b, err := ioutil.ReadAll(p.Reader)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Println(string(b))
+}
+
+// Output:
+// test

_test/len0.go

@@ -0,0 +1,13 @@
+package main
+
+func f(a []int) interface{} {
+	return len(a)
+}
+
+func main() {
+	a := []int{1, 2}
+	println(f(a).(int))
+}
+
+// Output:
+// 2