1 files changed, 715 insertions, 0 deletions
diff --git a/src/go/printer/testdata/expressions.input b/src/go/printer/testdata/expressions.input
new file mode 100644
index 000000000..d20a59350
--- /dev/null
+++ b/src/go/printer/testdata/expressions.input
@@ -0,0 +1,715 @@
+// Copyright 2009 The Go 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 expressions
+
+type T struct {
+	x, y, z int
+}
+
+var (
+	a, b, c, d, e int
+	under_bar int
+	longIdentifier1, longIdentifier2, longIdentifier3 int
+	t0, t1, t2 T
+	s string
+	p *int
+)
+
+
+func _() {
+	// no spaces around simple or parenthesized expressions
+	_ = (a+0)
+	_ = a+b
+	_ = a+b+c
+	_ = a+b-c
+	_ = a-b-c
+	_ = a+(b*c)
+	_ = a+(b/c)
+	_ = a-(b%c)
+	_ = 1+a
+	_ = a+1
+	_ = a+b+1
+	_ = s[a]
+	_ = s[a:]
+	_ = s[:b]
+	_ = s[1:2]
+	_ = s[a:b]
+	_ = s[0:len(s)]
+	_ = s[0]<<1
+	_ = (s[0]<<1)&0xf
+	_ = s[0] << 2 | s[1] >> 4
+	_ = "foo"+s
+	_ = s+"foo"
+	_ = 'a'+'b'
+	_ = len(s)/2
+	_ = len(t0.x)/a
+
+	// spaces around expressions of different precedence or expressions containing spaces
+	_ = a + -b
+	_ = a - ^b
+	_ = a / *p
+	_ = a + b*c
+	_ = 1 + b*c
+	_ = a + 2*c
+	_ = a + c*2
+	_ = 1 + 2*3
+	_ = s[1 : 2*3]
+	_ = s[a : b-c]
+	_ = s[0:]
+	_ = s[a+b]
+	_ = s[: b-c]
+	_ = s[a+b :]
+	_ = a[a<<b+1]
+	_ = a[a<<b+1 :]
+	_ = s[a+b : len(s)]
+	_ = s[len(s) : -a]
+	_ = s[a : len(s)+1]
+	_ = s[a : len(s)+1]+s
+
+	// spaces around operators with equal or lower precedence than comparisons
+	_ = a == b
+	_ = a != b
+	_ = a > b
+	_ = a >= b
+	_ = a < b
+	_ = a <= b
+	_ = a < b && c > d
+	_ = a < b || c > d
+
+	// spaces around "long" operands
+	_ = a + longIdentifier1
+	_ = longIdentifier1 + a
+	_ = longIdentifier1 + longIdentifier2 * longIdentifier3
+	_ = s + "a longer string"
+
+	// some selected cases
+	_ = a + t0.x
+	_ = a + t0.x + t1.x * t2.x
+	_ = a + b + c + d + e + 2*3
+	_ = a + b + c + 2*3 + d + e
+	_ = (a+b+c)*2
+	_ = a - b + c - d + (a+b+c) + d&e
+	_ = under_bar-1
+	_ = Open(dpath + "/file", O_WRONLY | O_CREAT, 0666)
+	_ = int(c0&_Mask4)<<18 | int(c1&_Maskx)<<12 | int(c2&_Maskx)<<6 | int(c3&_Maskx)
+
+	// test case for issue 8021
+	// want:
+	//  ([]bool{})[([]int{})[((1)+(((1)+((((1)*(((1)+(1))+(1)))+(1))*(1)))+(1)))]]
+	_ = ([]bool{})[([]int{})[((1) + (((((1) + (((((((1) * (((((1) + (1))) + (1))))) + (1))) * (1))))) + (1))))]]
+
+	// the parser does not restrict expressions that may appear as statements
+	true
+	42
+	"foo"
+	x
+	(x)
+	a+b
+	a+b+c
+	a+(b*c)
+	a+(b/c)
+	1+a
+	a+1
+	s[a]
+	x<<1
+	(s[0]<<1)&0xf
+	"foo"+s
+	x == y
+	x < y || z > 42
+}
+
+
+// slice expressions with cap
+func _() {
+	_ = x[a:b:c]
+	_ = x[a:b:c+d]
+	_ = x[a:b+d:c]
+	_ = x[a:b+d:c+d]
+	_ = x[a+d:b:c]
+	_ = x[a+d:b:c+d]
+	_ = x[a+d:b+d:c]
+	_ = x[a+d:b+d:c+d]
+
+	_ = x[:b:c]
+	_ = x[:b:c+d]
+	_ = x[:b+d:c]
+	_ = x[:b+d:c+d]
+}
+
+func _() {
+	_ = a+b
+	_ = a+b+c
+	_ = a+b*c
+	_ = a+(b*c)
+	_ = (a+b)*c
+	_ = a+(b*c*d)
+	_ = a+(b*c+d)
+
+	_ = 1<<x
+	_ = -1<<x
+	_ = 1<<x-1
+	_ = -1<<x-1
+
+	_ = f(a+b)
+	_ = f(a+b+c)
+	_ = f(a+b*c)
+	_ = f(a+(b*c))
+	_ = f(1<<x-1, 1<<x-2)
+
+	_ = 1<<d.logWindowSize-1
+
+	buf = make(x, 2*cap(b.buf) + n)
+
+	dst[i*3+2] = dbuf[0]<<2
+	dst[i*3+2] = dbuf[0]<<2 | dbuf[1]>>4
+
+	b.buf = b.buf[0:b.off+m+n]
+	b.buf = b.buf[0:b.off+m*n]
+	f(b.buf[0:b.off+m+n])
+
+	signed += ' '*8
+	tw.octal(header[148:155], chksum)
+
+	_ = x > 0 && i >= 0
+
+	x1, x0 := x>>w2, x&m2
+	z0 = t1<<w2+t0
+	z1 = (t1+t0>>w2)>>w2
+	q1, r1 := x1/d1, x1%d1
+	r1 = r1*b2 | x0>>w2
+	x1 = (x1<<z)|(x0>>(uint(w)-z))
+	x1 = x1<<z | x0>>(uint(w)-z)
+
+	_ = buf[0:len(buf)+1]
+	_ = buf[0:n+1]
+
+	a,b = b,a
+	a = b+c
+	a = b*c+d
+	_ = a*b+c
+	_ = a-b-c
+	_ = a-(b-c)
+	_ = a-b*c
+	_ = a-(b*c)
+	_ = a*b/c
+	_ = a/ *b
+	_ = x[a|^b]
+	_ = x[a/ *b]
+	_ = a& ^b
+	_ = a+ +b
+	_ = a- -b
+	_ = x[a*-b]
+	_ = x[a+ +b]
+	_ = x^y^z
+	_ = b[a>>24] ^ b[(a>>16)&0xFF] ^ b[(a>>8)&0xFF] ^ b[a&0xFF]
+	_ = len(longVariableName)*2
+
+	_ = token(matchType + xlength<<lengthShift + xoffset)
+}
+
+
+func f(x int, args ...int) {
+	f(0, args...)
+	f(1, args)
+	f(2, args[0])
+
+	// make sure syntactically legal code remains syntactically legal
+	f(3, 42 ...) // a blank must remain between 42 and ...
+	f(4, 42. ...)
+	f(5, 42....)
+	f(6, 42.0 ...)
+	f(7, 42.0...)
+	f(8, .42 ...)
+	f(9, .42...)
+	f(10, 42e0 ...)
+	f(11, 42e0...)
+
+	_ = 42 .x // a blank must remain between 42 and .x
+	_ = 42. .x
+	_ = 42..x
+	_ = 42.0 .x
+	_ = 42.0.x
+	_ = .42 .x
+	_ = .42.x
+	_ = 42e0 .x
+	_ = 42e0.x
+
+	// a blank must remain between the binary operator and the 2nd operand
+	_ = x/ *y
+	_ = x< -1
+	_ = x< <-1
+	_ = x+ +1
+	_ = x- -1
+	_ = x& &x
+	_ = x& ^x
+
+	_ = f(x/ *y, x< -1, x< <-1, x+ +1, x- -1, x& &x, x& ^x)
+}
+
+
+func _() {
+	_ = T{}
+	_ = struct{}{}
+	_ = [10]T{}
+	_ = [...]T{}
+	_ = []T{}
+	_ = map[int]T{}
+}
+
+
+// one-line structs/interfaces in composite literals (up to a threshold)
+func _() {
+	_ = struct{}{}
+	_ = struct{ x int }{0}
+	_ = struct{ x, y, z int }{0, 1, 2}
+	_ = struct{ int }{0}
+	_ = struct{ s struct { int } }{struct{ int}{0} }
+}
+
+
+func _() {
+	// do not modify literals
+	_ = "tab1	tab2	tab3	end"  // string contains 3 tabs
+	_ = "tab1 tab2 tab3 end"  // same string with 3 blanks - may be unaligned because editors see tabs in strings
+	_ = ""  // this comment should be aligned with the one on the previous line
+	_ = ``
+	_ = `
+`
+_ = `foo
+		bar`
+	_ = `three spaces before the end of the line starting here:   
+they must not be removed`
+}
+
+
+func _() {
+	// smart handling of indentation for multi-line raw strings
+	var _ = ``
+	var _ = `foo`
+	var _ = `foo
+bar`
+
+
+var _ =
+	``
+var _ =
+	`foo`
+var _ =
+	// the next line should remain indented
+	`foo
+bar`
+
+
+	var _ = // comment
+		``
+	var _ = // comment
+		`foo`
+	var _ = // comment
+		// the next line should remain indented
+		`foo
+bar`
+
+
+var _ = /* comment */ ``
+var _ = /* comment */ `foo`
+var _ = /* comment */ `foo
+bar`
+
+
+	var _ = /* comment */
+		``
+	var _ = /* comment */
+		`foo`
+	var _ = /* comment */
+		// the next line should remain indented
+		`foo
+bar`
+
+
+var board = []int(
+	`...........
+...........
+....●●●....
+....●●●....
+..●●●●●●●..
+..●●●○●●●..
+..●●●●●●●..
+....●●●....
+....●●●....
+...........
+...........
+`)
+
+
+	var state = S{
+		"foo",
+		// the next line should remain indented
+		`...........
+...........
+....●●●....
+....●●●....
+..●●●●●●●..
+..●●●○●●●..
+..●●●●●●●..
+....●●●....
+....●●●....
+...........
+...........
+`,
+		"bar",
+	}
+}
+
+
+func _() {
+	// one-line function literals (body is on a single line)
+	_ = func() {}
+	_ = func() int { return 0 }
+	_ = func(x, y int) bool { m := (x+y)/2; return m < 0 }
+
+	// multi-line function literals (body is not on one line)
+	_ = func() {
+	}
+	_ = func() int {
+		return 0
+	}
+	_ = func(x, y int) bool {
+		m := (x+y)/2; return x < y }
+
+	f(func() {
+	})
+	f(func() int {
+		return 0
+	})
+	f(func(x, y int) bool {
+		m := (x+y)/2; return x < y })
+}
+
+
+func _() {
+	_ = [][]int {
+		[]int{1},
+		[]int{1, 2},
+		[]int{1, 2, 3},
+	}
+	_ = [][]int {
+		{1},
+		[]int{1, 2},
+		[]int{1, 2, 3},
+	}
+	_ = [][]int {
+		{1},
+		{1, 2},
+		{1, 2, 3},
+	}
+	_ = [][]int {{1}, {1, 2}, {1, 2, 3}}
+}
+
+
+// various multi-line expressions
+func _() {
+	// do not add extra indentation to multi-line string lists
+	_ = "foo" + "bar"
+	_ = "foo" +
+	"bar" +
+	"bah"
+	_ = []string {
+		"abc" +
+		"def",
+		"foo" +
+		"bar",
+	}
+}
+
+
+const _ = F1 +
+	`string = "%s";` +
+	`ptr = *;` +
+	`datafmt.T2 = s ["-" p "-"];`
+
+
+const _ =
+	`datafmt "datafmt";` +
+	`default = "%v";` +
+	`array = *;` +
+	`datafmt.T3 = s  {" " a a / ","};`
+
+
+const _ = `datafmt "datafmt";` +
+`default = "%v";` +
+`array = *;` +
+`datafmt.T3 = s  {" " a a / ","};`
+
+
+func _() {
+	_ = F1 +
+		`string = "%s";` +
+		`ptr = *;` +
+		`datafmt.T2 = s ["-" p "-"];`
+
+	_ =
+		`datafmt "datafmt";` +
+		`default = "%v";` +
+		`array = *;` +
+		`datafmt.T3 = s  {" " a a / ","};`
+
+	_ = `datafmt "datafmt";` +
+	`default = "%v";` +
+	`array = *;` +
+	`datafmt.T3 = s  {" " a a / ","};`
+}
+
+
+func _() {
+	// respect source lines in multi-line expressions
+	_ = a+
+	b+
+	c
+	_ = a < b ||
+		b < a
+	_ = "933262154439441526816992388562667004907159682643816214685929" +
+	"638952175999932299156089414639761565182862536979208272237582" +
+	"51185210916864000000000000000000000000"  // 100!
+	_ = "170141183460469231731687303715884105727"  // prime
+}
+
+
+// Alignment after overlong lines
+const (
+	_ = "991"
+	_ = "2432902008176640000"  // 20!
+	_ = "933262154439441526816992388562667004907159682643816214685929" +
+	"638952175999932299156089414639761565182862536979208272237582" +
+	"51185210916864000000000000000000000000"  // 100!
+	_ = "170141183460469231731687303715884105727"  // prime
+)
+
+
+// Correct placement of operators and comments in multi-line expressions
+func _() {
+	_ = a +  // comment
+		b +  // comment
+		c
+	_ = "a"	+
+		"b" +	// comment
+		"c"
+	_ = "ba0408" + "7265717569726564"     // field 71, encoding 2, string "required"
+}
+
+
+// Correct placement of terminating comma/closing parentheses in multi-line calls.
+func _() {
+	f(1,
+		2,
+		3)
+	f(1,
+		2,
+		3,
+	)
+	f(1,
+		2,
+		3)  // comment
+	f(1,
+		2,
+		3,  // comment
+	)
+	f(1,
+		2,
+		3)// comment
+	f(1,
+		2,
+		3,// comment
+	)
+}
+
+
+// Align comments in multi-line lists of single-line expressions.
+var txpix = [NCOL]draw.Color{
+	draw.Yellow, // yellow
+	draw.Cyan, // cyan
+	draw.Green, // lime green
+	draw.GreyBlue, // slate
+	draw.Red, /* red */
+	draw.GreyGreen, /* olive green */
+	draw.Blue, /* blue */
+	draw.Color(0xFF55AAFF), /* pink */
+	draw.Color(0xFFAAFFFF), /* lavender */
+	draw.Color(0xBB005DFF), /* maroon */
+}
+
+
+func same(t, u *Time) bool {
+	// respect source lines in multi-line expressions
+	return t.Year == u.Year &&
+		t.Month == u.Month &&
+		t.Day == u.Day &&
+		t.Hour == u.Hour &&
+		t.Minute == u.Minute &&
+		t.Second == u.Second &&
+		t.Weekday == u.Weekday &&
+		t.ZoneOffset == u.ZoneOffset &&
+		t.Zone == u.Zone
+}
+
+
+func (p *parser) charClass() {
+	// respect source lines in multi-line expressions
+	if cc.negate && len(cc.ranges) == 2 &&
+		cc.ranges[0] == '\n' && cc.ranges[1] == '\n' {
+		nl := new(_NotNl)
+		p.re.add(nl)
+	}
+}
+
+
+func addState(s []state, inst instr, match []int) {
+	// handle comments correctly in multi-line expressions
+	for i := 0; i < l; i++ {
+		if s[i].inst.index() == index && // same instruction
+		   s[i].match[0] < pos {	// earlier match already going; leftmost wins
+		   	return s
+		 }
+	}
+}
+
+func (self *T) foo(x int) *T { return self }
+
+func _() { module.Func1().Func2() }
+
+func _() {
+	_ = new(T).
+		foo(1).
+			foo(2).
+		foo(3)
+
+	_ = new(T).
+	foo(1).
+	foo(2). // inline comments
+	foo(3)
+
+	_ = new(T).foo(1).foo(2).foo(3)
+
+	// handle multiline argument list correctly
+	_ = new(T).
+	foo(
+		1).
+		foo(2)
+
+	_ = new(T).foo(
+		1).foo(2)
+
+	_ = Array[3 +
+4]
+
+	_ = Method(1, 2,
+		3)
+
+	_ = new(T).
+   foo().
+   bar() . (*Type)
+
+	_ = new(T).
+foo().
+bar().(*Type).
+baz()
+
+	_ = new(T).
+	foo().
+	bar()["idx"]
+
+	_ = new(T).
+	foo().
+	bar()["idx"]	.
+	baz()
+
+	_ = new(T).
+	foo().
+	bar()[1:2]
+
+	_ = new(T).
+	foo().
+	bar()[1:2].
+	baz()
+
+	_ = new(T).
+		Field.
+		Array[3+
+       		4].
+		Table ["foo"].
+		Blob. (*Type).
+	Slices[1:4].
+	Method(1, 2,
+	3).
+		Thingy
+
+	_ = a.b.c
+	_ = a.
+	b.
+	c
+	_ = a.b().c
+	_ = a.
+	b().
+	c
+	_ = a.b[0].c
+	_ = a.
+	b[0].
+	c
+	_ = a.b[0:].c
+	_ = a.
+	b[0:].
+	c
+	_ = a.b.(T).c
+	_ = a.
+	b.
+	(T).
+	c
+}
+
+
+// Don't introduce extra newlines in strangely formatted expression lists.
+func f() {
+	// os.Open parameters should remain on two lines
+	if writer, err = os.Open(outfile, s.O_WRONLY|os.O_CREATE|
+		os.O_TRUNC, 0666); err != nil {
+	    log.Fatal(err)
+	}
+}
+
+// Handle multi-line argument lists ending in ... correctly.
+// Was issue 3130.
+func _() {
+	_ = append(s, a...)
+	_ = append(
+		s, a...)
+	_ = append(s,
+		a...)
+	_ = append(
+		s,
+		a...)
+	_ = append(s, a...,
+	)
+	_ = append(s,
+		a...,
+	)
+	_ = append(
+		s,
+		a...,
+	)
+}
+
+// Literal function types in conversions must be parenthesized;
+// for now go/parser accepts the unparenthesized form where it
+// is non-ambiguous.
+func _() {
+	// these conversions should be rewritten to look
+	// the same as the parenthesized conversions below
+	_ = func()()(nil)
+	_ = func(x int)(float)(nil)
+	_ = func() func() func()()(nil)
+
+	_ = (func()())(nil)
+	_ = (func(x int)(float))(nil)
+	_ = (func() func() func()())(nil)
+}