errchk: allow multiple patterns

// ERROR "pattern1" "pattern2"

means that there has to be one or more
lines matching pattern1 and then excluding
those, there have to be one or more lines
matching pattern2.  So if you expect two
different error messages from a particular
line, writing two separate patterns checks
that both errors are produced.

Also, errchk now flags lines that produce
more errors than expected.  Before, as long as
at least one error matched the pattern, all the
others were ignored.

Revise tests to expect or silence these
additional errors.

R=lvd, r, iant
CC=golang-dev
https://golang.org/cl/4869044

test/declbad.go

@@ -40,7 +40,7 @@ func main() {
 	{
 		// single redeclaration
 		i, f, s := f3()
-		i := f1() // ERROR "redeclared|no new|incompatible"
+		i := 1 // ERROR "redeclared|no new|incompatible"
 		_, _, _ = i, f, s
 	}
 	// double redeclaration

test/errchk

@@ -88,13 +88,19 @@ sub chk {
 		$line++;
 		next if $src =~ m|////|;  # double comment disables ERROR
 		next unless $src =~ m|// (GC_)?ERROR (.*)|;
-		$regexp = $2;
-		if($regexp !~ /^"([^"]*)"/) {
+		my $all = $2;
+		if($all !~ /^"([^"]*)"/) {
 			print STDERR "$file:$line: malformed regexp\n";
 			next;
 		}
-		$regexp = $1;
-		
+		@errmsg = grep { /$file:$line[:[]/ } @out;
+		@out = grep { !/$file:$line[:[]/ } @out;
+		if(@errmsg == 0) {
+			bug();
+			print STDERR "errchk: $file:$line: missing expected error: '$all'\n";
+			next;
+		}
+		foreach my $regexp ($all =~ /"([^"]*)"/g) {
 			# Turn relative line number in message into absolute line number.
 			if($regexp =~ /LINE(([+-])([0-9]+))?/) {
 				my $n = $line;
@@ -108,21 +114,20 @@ sub chk {
 				$regexp = "$`$file:$n$'";
 			}
 	
-		@errmsg = grep { /$file:$line[:[]/ } @out;
-		@out = grep { !/$file:$line[:[]/ } @out;
-		if(@errmsg == 0) {
+			@match = grep { /$regexp/ } @errmsg;
+			if(@match == 0) {
 				bug();
-			print STDERR "errchk: $file:$line: missing expected error: '$regexp'\n";
+				print STDERR "errchk: $file:$line: error messages do not match '$regexp'\n";
 				next;
 			}
-		@match = grep { /$regexp/ } @errmsg;
-		if(@match == 0) {
+			@errmsg = grep { !/$regexp/ } @errmsg;
+		}
+		if(@errmsg != 0) {
 			bug();
-			print STDERR "errchk: $file:$line: error message does not match '$regexp'\n";
+			print STDERR "errchk: $file:$line: unmatched error messages:\n";
 			foreach my $l (@errmsg) {
 				print STDERR "> $l";
 			}
-			next;
 		}
 	}
 }

test/fixedbugs/bug205.go

@@ -12,7 +12,7 @@ var m map[string]int;
 
 func main() {
 	println(t["hi"]);	// ERROR "integer"
-	println(s["hi"]);	// ERROR "integer"
+	println(s["hi"]);	// ERROR "integer" "to type uint"
 	println(m[0]);	// ERROR "map index"
 }
 

test/fixedbugs/bug228.go

@@ -8,7 +8,7 @@ package main
 
 func f(x int, y ...int)	// ok
 
-func g(x int, y float) (...)	// ERROR "[.][.][.]"
+func g(x int, y float) (...)	// ERROR "[.][.][.]" "final argument"
 
 func h(x, y ...int)		// ERROR "[.][.][.]"
 

test/fixedbugs/bug229.go

@@ -16,5 +16,5 @@ func main() {
 
 	t.ch = nil	// ERROR "unexported"
 	
-	println(testing.anyLowercaseName("asdf"))	// ERROR "unexported"
+	println(testing.anyLowercaseName("asdf"))	// ERROR "unexported" "undefined: testing.anyLowercaseName"
 }

test/fixedbugs/bug231.go

@@ -17,6 +17,6 @@ func main() {
 	var i I
 	
 	i = m
-	i = t	// ERROR "not a method|has no methods"
+	i = t	// ERROR "not a method|has no methods" "does not implement I"
 	_ = i
 }

test/fixedbugs/bug297.go

@@ -11,5 +11,5 @@ package main
 type ByteSize float64
 const (
 	_ = iota;   // ignore first value by assigning to blank identifier
-	KB ByteSize = 1<<(10*X) // ERROR "undefined"
+	KB ByteSize = 1<<(10*X) // ERROR "undefined" "as type ByteSize"
 )

test/fixedbugs/bug351.go

@@ -6,6 +6,8 @@
 
 package main
 
+var x int
+
 func main() {
 	(x) := 0  // ERROR "non-name [(]x[)]"
 }

test/fixedbugs/bug359.go

@@ -16,7 +16,7 @@ type Painting struct {
 }
 
 func (p Painting) Foo() {
-	for e := p.fragments; e.Front() != nil; e = e.Next() {  // ERROR "unexported field"
+	for e := p.fragments; e.Front() != nil; {  // ERROR "unexported field"
 	}
 }
 

test/import1.go

@@ -9,9 +9,9 @@
 package main
 
 import "bufio"	// GCCGO_ERROR "previous|not used"
-import bufio "os"	// ERROR "redeclared|redefinition|incompatible"
+import bufio "os"	// ERROR "redeclared|redefinition|incompatible" "imported and not used"
 
 import (
 	"fmt"	// GCCGO_ERROR "previous|not used"
-	fmt "math"	// ERROR "redeclared|redefinition|incompatible"
+	fmt "math"	// ERROR "redeclared|redefinition|incompatible" "imported and not used"
 )

test/initializerr.go

@@ -17,7 +17,7 @@ type T struct {
 var x = 1
 var a1 = S { 0, X: 1 }	// ERROR "mixture|undefined"
 var a2 = S { Y: 3, Z: 2, Y: 3 } // ERROR "duplicate"
-var a3 = T { 1, 2, 3, 4, 5, 6 }	// ERROR "convert|too many"
+var a3 = T { S{}, 2, 3, 4, 5, 6 }	// ERROR "convert|too many"
 var a4 = [5]byte{ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 }	// ERROR "index|too many"
 var a5 = []byte { x: 2 }	// ERROR "index"
 

test/interface/explicit.go

@@ -48,7 +48,7 @@ func main() {
 	i2 = I2(i) // ERROR "invalid|missing N method"
 
 	e = E(t) // ok
-	t = T(e) // ERROR "need explicit|need type assertion|incompatible"
+	t = T(e) // ERROR "need explicit|need type assertion|incompatible" "as type [*]T"
 }
 
 type M interface {

test/interface/pointer.go

@@ -33,5 +33,5 @@ func main() {
 	print("call addinst\n")
 	var x Inst = AddInst(new(Start)) // ERROR "pointer to interface"
 	print("return from  addinst\n")
-	var x *Inst = new(Start)  // ERROR "pointer to interface"
+	var y *Inst = new(Start)  // ERROR "pointer to interface"
 }

test/nul1.go

@@ -39,7 +39,7 @@ var y = ` + "`in raw string \x00 foo`" + `  // ERROR "NUL"
 
 /* in other comment ` + "\x00" + ` */ // ERROR "NUL"
 
-/* in source code */ ` + "\x00" + `// ERROR "NUL"
+/* in source code */ ` + "\x00" + `// ERROR "NUL" "illegal character"
 
 var xx = "in string ` + "\xc2\xff" + `" // ERROR "UTF-8"
 
@@ -50,9 +50,9 @@ var yy = ` + "`in raw string \xff foo`" + `  // ERROR "UTF-8"
 /* in other comment ` + "\xe0\x00\x00" + ` */ // ERROR "UTF-8|NUL"
 
 /* in variable name */
-var z` + "\xc1\x81" + ` int // ERROR "UTF-8"
+var z` + "\xc1\x81" + ` int // ERROR "UTF-8" "invalid identifier character"
 
-/* in source code */ ` + "\xc2A" + `// ERROR "UTF-8"
+/* in source code */ ` + "var \xc2A int" + `// ERROR "UTF-8" "invalid identifier character"
 
 `)
 }

test/rename1.go

@@ -10,7 +10,7 @@ func main() {
 	var n byte       // ERROR "not a type|expected type"
 	var y = float(0) // ERROR "cannot call|expected function"
 	const (
-		a = 1 + iota // ERROR "string|incompatible types"
+		a = 1 + iota // ERROR "string|incompatible types" "convert iota"
 	)
 
 }

test/shift1.go

@@ -16,13 +16,13 @@ func h(x float64) int     { return 0 }
 var (
 	s uint    = 33
 	u         = 1.0 << s // ERROR "invalid operation"
-	v float32 = 1 << s   // ERROR "invalid operation"
+	v float32 = 1 << s   // ERROR "invalid operation" "as type float32"
 )
 
 // non-constant shift expressions
 var (
-	e1       = g(2.0 << s) // ERROR "invalid operation"
-	f1       = h(2 << s)   // ERROR "invalid operation"
+	e1       = g(2.0 << s) // ERROR "invalid operation" "as type interface"
+	f1       = h(2 << s)   // ERROR "invalid operation" "as type float64"
 	g1 int64 = 1.1 << s    // ERROR "truncated"
 )