go/parser: if and switch statements still can have empty init statements
This is a fix for the overly aggressive CL 4173075.
Ran all tests.
R=r, rsc
CC=golang-dev
https://golang.org/cl/4203041
diff --git a/src/pkg/go/parser/parser.go b/src/pkg/go/parser/parser.go
index 77bcc44..7c5843f 100644
--- a/src/pkg/go/parser/parser.go
+++ b/src/pkg/go/parser/parser.go
@@ -1339,13 +1339,18 @@
{
prevLev := p.exprLev
p.exprLev = -1
- s = p.parseSimpleStmt(false)
if p.tok == token.SEMICOLON {
p.next()
x = p.parseExpr()
} else {
- x = p.makeExpr(s)
- s = nil
+ s = p.parseSimpleStmt(false)
+ if p.tok == token.SEMICOLON {
+ p.next()
+ x = p.parseExpr()
+ } else {
+ x = p.makeExpr(s)
+ s = nil
+ }
}
p.exprLev = prevLev
}
@@ -1447,7 +1452,9 @@
if p.tok != token.LBRACE {
prevLev := p.exprLev
p.exprLev = -1
- s2 = p.parseSimpleStmt(false)
+ if p.tok != token.SEMICOLON {
+ s2 = p.parseSimpleStmt(false)
+ }
if p.tok == token.SEMICOLON {
p.next()
s1 = s2
@@ -1580,7 +1587,6 @@
if p.tok != token.LBRACE {
prevLev := p.exprLev
p.exprLev = -1
-
if p.tok != token.SEMICOLON {
s2 = p.parseSimpleStmt(false)
}
@@ -1596,7 +1602,6 @@
s3 = p.parseSimpleStmt(false)
}
}
-
p.exprLev = prevLev
}
diff --git a/src/pkg/go/parser/parser_test.go b/src/pkg/go/parser/parser_test.go
index 7123870..3853562 100644
--- a/src/pkg/go/parser/parser_test.go
+++ b/src/pkg/go/parser/parser_test.go
@@ -19,6 +19,8 @@
[]byte(nil),
"foo!",
`package p; func f() { if /* should have condition */ {} };`,
+ `package p; func f() { if ; /* should have condition */ {} };`,
+ `package p; func f() { if f(); /* should have condition */ {} };`,
}
@@ -33,21 +35,23 @@
var validPrograms = []interface{}{
- "package main\n",
- `package main;`,
- `package main; import "fmt"; func main() { fmt.Println("Hello, World!") };`,
- `package main; func main() { if f(T{}) {} };`,
- `package main; func main() { _ = (<-chan int)(x) };`,
- `package main; func main() { _ = (<-chan <-chan int)(x) };`,
- `package main; func f(func() func() func());`,
- `package main; func f(...T);`,
- `package main; func f(float, ...int);`,
- `package main; func f(x int, a ...int) { f(0, a...); f(1, a...,) };`,
- `package main; type T []int; var a []bool; func f() { if a[T{42}[0]] {} };`,
- `package main; type T []int; func g(int) bool { return true }; func f() { if g(T{42}[0]) {} };`,
- `package main; type T []int; func f() { for _ = range []int{T{42}[0]} {} };`,
- `package main; var a = T{{1, 2}, {3, 4}}`,
- `package main; func f() { select { case <- c: case c <- d: case c <- <- d: case <-c <- d: } };`,
+ "package p\n",
+ `package p;`,
+ `package p; import "fmt"; func f() { fmt.Println("Hello, World!") };`,
+ `package p; func f() { if f(T{}) {} };`,
+ `package p; func f() { _ = (<-chan int)(x) };`,
+ `package p; func f() { _ = (<-chan <-chan int)(x) };`,
+ `package p; func f(func() func() func());`,
+ `package p; func f(...T);`,
+ `package p; func f(float, ...int);`,
+ `package p; func f(x int, a ...int) { f(0, a...); f(1, a...,) };`,
+ `package p; type T []int; var a []bool; func f() { if a[T{42}[0]] {} };`,
+ `package p; type T []int; func g(int) bool { return true }; func f() { if g(T{42}[0]) {} };`,
+ `package p; type T []int; func f() { for _ = range []int{T{42}[0]} {} };`,
+ `package p; var a = T{{1, 2}, {3, 4}}`,
+ `package p; func f() { select { case <- c: case c <- d: case c <- <- d: case <-c <- d: } };`,
+ `package p; func f() { if ; true {} };`,
+ `package p; func f() { switch ; {} };`,
}
diff --git a/src/pkg/go/printer/testdata/statements.golden b/src/pkg/go/printer/testdata/statements.golden
index 98bc031..2900602 100644
--- a/src/pkg/go/printer/testdata/statements.golden
+++ b/src/pkg/go/printer/testdata/statements.golden
@@ -12,10 +12,16 @@
func _() {
if true {
}
+ if true {
+ } // no semicolon printed
if expr {
}
if expr {
+ } // no semicolon printed
+ if expr {
} // no parens printed
+ if expr {
+ } // no semicolon and parens printed
if x := expr; true {
use(x)
}
@@ -29,10 +35,16 @@
func _() {
switch {
}
+ switch {
+ } // no semicolon printed
switch expr {
}
switch expr {
+ } // no semicolon printed
+ switch expr {
} // no parens printed
+ switch expr {
+ } // no semicolon and parens printed
switch x := expr; {
default:
use(
diff --git a/src/pkg/go/printer/testdata/statements.input b/src/pkg/go/printer/testdata/statements.input
index c8df052..21e61ef 100644
--- a/src/pkg/go/printer/testdata/statements.input
+++ b/src/pkg/go/printer/testdata/statements.input
@@ -11,9 +11,12 @@
// Formatting of if-statement headers.
func _() {
if true {}
+ if; true {} // no semicolon printed
if expr{}
+ if;expr{} // no semicolon printed
if (expr){} // no parens printed
- if x:=expr; true {
+ if;((expr)){} // no semicolon and parens printed
+ if x:=expr;true{
use(x)}
if x:=expr; expr {use(x)}
}
@@ -22,8 +25,11 @@
// Formatting of switch-statement headers.
func _() {
switch {}
+ switch;{} // no semicolon printed
switch expr {}
+ switch;expr{} // no semicolon printed
switch (expr) {} // no parens printed
+ switch;((expr)){} // no semicolon and parens printed
switch x := expr; { default:use(
x)
}
@@ -112,7 +118,7 @@
if (((x))) {}
if ([]T{}) {}
if (([]T{})) {}
- if (((([]T{})))) {}
+ if ; (((([]T{})))) {}
for (x) {}
for (((x))) {}
@@ -123,21 +129,21 @@
switch (x) {}
switch (((x))) {}
switch ([]T{}) {}
- switch (((([]T{})))) {}
+ switch ; (((([]T{})))) {}
for _ = range ((([]T{T{42}}))) {}
// leave parentheses - composite literals start with a type name
if (T{}) {}
if ((T{})) {}
- if ((((T{})))) {}
+ if ; ((((T{})))) {}
for (T{}) {}
for ((T{})) {}
for ; ((((T{})))) ; {}
switch (T{}) {}
- switch ((((T{})))) {}
+ switch ; ((((T{})))) {}
for _ = range (((T1{T{42}}))) {}
