test: a number of fixes.

Details:
- reorder.go: delete p8.
  (Once expectation is changed per b/4627 it is identical to p1.)
- switch.go: added some more (degenerate) switches.
- range.go: improved error messages in a few cases.
- method.go: added tests of calls to promoted methods.

R=iant
CC=golang-dev
https://golang.org/cl/7306087

test/method.go

@@ -128,13 +128,13 @@ func main() {
 		panic("fail")
 	}
 
-	var zs struct { S }
-	var zps struct { *S1 }
-	var zi struct { I }
-	var zpi struct { *I1 }
-	var zpt struct { *T1 }
-	var zt struct { T }
-	var zv struct { Val }
+	var zs struct{ S }
+	var zps struct{ *S1 }
+	var zi struct{ I }
+	var zpi struct{ *I1 }
+	var zpt struct{ *T1 }
+	var zt struct{ T }
+	var zv struct{ Val }
 
 	if zs.val() != 1 {
 		println("zs.val:", zs.val())
@@ -247,4 +247,61 @@ func main() {
 		println("zv.val():", zv.val())
 		panic("fail")
 	}
+
+	promotion()
+}
+
+type A struct{ B }
+type B struct {
+	C
+	*D
+}
+type C int
+
+func (C) f()  {} // value receiver, direct field of A
+func (*C) g() {} // pointer receiver
+
+type D int
+
+func (D) h()  {} // value receiver, indirect field of A
+func (*D) i() {} // pointer receiver
+
+func expectPanic() {
+	if r := recover(); r == nil {
+		panic("expected nil dereference")
+	}
+}
+
+func promotion() {
+	var a A
+	// Addressable value receiver.
+	a.f()
+	a.g()
+	func() {
+		defer expectPanic()
+		a.h() // dynamic error: nil dereference in a.B.D->f()
+	}()
+	a.i()
+
+	// Non-addressable value receiver.
+	A(a).f()
+	// A(a).g() // static error: cannot call pointer method on A literal.B.C
+	func() {
+		defer expectPanic()
+		A(a).h() // dynamic error: nil dereference in A().B.D->f()
+	}()
+	A(a).i()
+
+	// Pointer receiver.
+	(&a).f()
+	(&a).g()
+	func() {
+		defer expectPanic()
+		(&a).h() // dynamic error: nil deref: nil dereference in (&a).B.D->f()
+	}()
+	(&a).i()
+
+	c := new(C)
+	c.f() // makes a copy
+	c.g()
 }

test/range.go

@@ -55,10 +55,10 @@ func testslice() {
 		panic("fail")
 	}
 	if s != 15 {
-		println("wrong sum ranging over makeslice")
+		println("wrong sum ranging over makeslice", s)
 		panic("fail")
 	}
-	
+
 	x := []int{10, 20}
 	y := []int{99}
 	i := 1
@@ -82,7 +82,7 @@ func testslice1() {
 		panic("fail")
 	}
 	if s != 10 {
-		println("wrong sum ranging over makeslice")
+		println("wrong sum ranging over makeslice", s)
 		panic("fail")
 	}
 }
@@ -106,7 +106,7 @@ func testarray() {
 		panic("fail")
 	}
 	if s != 15 {
-		println("wrong sum ranging over makearray")
+		println("wrong sum ranging over makearray", s)
 		panic("fail")
 	}
 }
@@ -122,7 +122,7 @@ func testarray1() {
 		panic("fail")
 	}
 	if s != 10 {
-		println("wrong sum ranging over makearray")
+		println("wrong sum ranging over makearray", s)
 		panic("fail")
 	}
 }
@@ -155,7 +155,7 @@ func testarrayptr() {
 		panic("fail")
 	}
 	if s != 15 {
-		println("wrong sum ranging over makearrayptr")
+		println("wrong sum ranging over makearrayptr", s)
 		panic("fail")
 	}
 }
@@ -171,7 +171,7 @@ func testarrayptr1() {
 		panic("fail")
 	}
 	if s != 10 {
-		println("wrong sum ranging over makearrayptr")
+		println("wrong sum ranging over makearrayptr", s)
 		panic("fail")
 	}
 }
@@ -195,7 +195,7 @@ func teststring() {
 		panic("fail")
 	}
 	if s != 'a'+'b'+'c'+'d'+'☺' {
-		println("wrong sum ranging over makestring")
+		println("wrong sum ranging over makestring", s)
 		panic("fail")
 	}
 }
@@ -211,7 +211,7 @@ func teststring1() {
 		panic("fail")
 	}
 	if s != 10 {
-		println("wrong sum ranging over makestring")
+		println("wrong sum ranging over makestring", s)
 		panic("fail")
 	}
 }
@@ -235,7 +235,7 @@ func testmap() {
 		panic("fail")
 	}
 	if s != 'a'+'b'+'c'+'d'+'☺' {
-		println("wrong sum ranging over makemap")
+		println("wrong sum ranging over makemap", s)
 		panic("fail")
 	}
 }
@@ -251,7 +251,7 @@ func testmap1() {
 		panic("fail")
 	}
 	if s != 10 {
-		println("wrong sum ranging over makemap")
+		println("wrong sum ranging over makemap", s)
 		panic("fail")
 	}
 }

test/reorder.go

@@ -19,7 +19,6 @@ func main() {
 	p6()
 	p7()
 	p8()
-	p9()
 }
 
 var gx []int
@@ -43,7 +42,7 @@ func check3(x, y, z, xx, yy, zz int) {
 }
 
 func p1() {
-	x := []int{1,2,3}
+	x := []int{1, 2, 3}
 	i := 0
 	i, x[i] = 1, 100
 	_ = i
@@ -51,7 +50,7 @@ func p1() {
 }
 
 func p2() {
-	x := []int{1,2,3}
+	x := []int{1, 2, 3}
 	i := 0
 	x[i], i = 100, 1
 	_ = i
@@ -59,7 +58,7 @@ func p2() {
 }
 
 func p3() {
-	x := []int{1,2,3}
+	x := []int{1, 2, 3}
 	y := x
 	gx = x
 	x[1], y[0] = f(0), f(1)
@@ -67,7 +66,7 @@ func p3() {
 }
 
 func p4() {
-	x := []int{1,2,3}
+	x := []int{1, 2, 3}
 	y := x
 	gx = x
 	x[1], y[0] = gx[0], gx[1]
@@ -75,7 +74,7 @@ func p4() {
 }
 
 func p5() {
-	x := []int{1,2,3}
+	x := []int{1, 2, 3}
 	y := x
 	p := &x[0]
 	q := &x[1]
@@ -90,7 +89,7 @@ func p6() {
 	px := &x
 	py := &y
 	*px, *py = y, x
-	check3(x, y, z, 2, 1, 3)	
+	check3(x, y, z, 2, 1, 3)
 }
 
 func f1(x, y, z int) (xx, yy, zz int) {
@@ -107,21 +106,6 @@ func p7() {
 }
 
 func p8() {
-	x := []int{1,2,3}
-
-	defer func() {
-		err := recover()
-		if err == nil {
-			panic("not panicking")
-		}
-		check(x, 100, 2, 3)
-	}()
-
-	i := 0
-	i, x[i], x[5] = 1, 100, 500
-}
-
-func p9() {
 	m := make(map[int]int)
 	m[0] = len(m)
 	if m[0] != 0 {

test/switch.go

@@ -307,9 +307,9 @@ func main() {
 
 	// switch on array.
 	switch ar := [3]int{1, 2, 3}; ar {
-	case [3]int{1,2,3}:
+	case [3]int{1, 2, 3}:
 		assert(true, "[1 2 3]")
-	case [3]int{4,5,6}:
+	case [3]int{4, 5, 6}:
 		assert(false, "ar should be [1 2 3]")
 	default:
 		assert(false, "ar should be [1 2 3]")
@@ -327,12 +327,57 @@ func main() {
 		assert(false, "c1 did not match itself")
 	}
 
+	// empty switch
+	switch {
+	}
+
+	// empty switch with default case.
+	fired = false
+	switch {
+	default:
+		fired = true
+	}
+	assert(fired, "fail")
+
+	// Default and fallthrough.
+	count = 0
+	switch {
+	default:
+		count++
+		fallthrough
+	case false:
+		count++
+	}
+	assert(count == 2, "fail")
+
+	// fallthrough to default, which is not at end.
+	count = 0
+	switch i5 {
+	case 5:
+		count++
+		fallthrough
+	default:
+		count++
+	case 6:
+		count++
+	}
+	assert(count == 2, "fail")
+
+	// fallthrough in final case.
+	count = 0
+	switch i5 {
+	case 5:
+		count++
+		fallthrough
+	}
+	assert(count == 1, "fail")
+
 	i := 0
 	switch x := 5; {
-		case i < x:
-			os.Exit(0)
-		case i == x:
-		case i > x:
-			os.Exit(1)
+	case i < x:
+		os.Exit(0)
+	case i == x:
+	case i > x:
+		os.Exit(1)
 	}
 }