- fixed bugs related to the empty statement

  (now in sync with the spec and with 6g)
- fixed incorrect logging statement in gds

R=r
OCL=24970
CL=24970

diff --git a/usr/gri/pretty/ast.go b/usr/gri/pretty/ast.go
index b3260a1fa4f0060dd3e5617e9c05fbfa96f7e1c9..df8bfbf2cd005449ebc3773a87a4a0ef82dd340f 100644 (file)
--- a/usr/gri/pretty/ast.go
+++ b/usr/gri/pretty/ast.go
@@ -390,6 +390,10 @@ type (
                Tok int;  // BREAK, CONTINUE, GOTO, FALLTHROUGH
                Label *Ident;  // if any, or nil
        };
+       
+       EmptyStat struct {
+               Pos int;  // position of ";"
+       };
 )
 
 
@@ -405,6 +409,7 @@ type StatVisitor interface {
        DoSwitchStat(s *SwitchStat);
        DoSelectStat(s *SelectStat);
        DoControlFlowStat(s *ControlFlowStat);
+       DoEmptyStat(s *EmptyStat);
 }
 
 
@@ -419,6 +424,7 @@ func (s *CaseClause) Visit(v StatVisitor) { v.DoCaseClause(s); }
 func (s *SwitchStat) Visit(v StatVisitor) { v.DoSwitchStat(s); }
 func (s *SelectStat) Visit(v StatVisitor) { v.DoSelectStat(s); }
 func (s *ControlFlowStat) Visit(v StatVisitor) { v.DoControlFlowStat(s); }
+func (s *EmptyStat) Visit(v StatVisitor) { v.DoEmptyStat(s); }
 
 
 // ----------------------------------------------------------------------------

diff --git a/usr/gri/pretty/gds.go b/usr/gri/pretty/gds.go
index d5637cc9df8cbb6db1c04e05f2c5cc82f46823b8..284a9d507303c17b252b00dbae08eb9b167a0b9a 100644 (file)
--- a/usr/gri/pretty/gds.go
+++ b/usr/gri/pretty/gds.go
@@ -155,7 +155,7 @@ func main() {
        http.Handle("/", http.HandlerFunc(serve));
        err2 := http.ListenAndServe(":" + *port, nil);
        if err2 != nil {
-               log.Exitf("ListenAndServe: ", err2.String())
+               log.Exitf("ListenAndServe: %s", err2.String())
        }
 }
 

diff --git a/usr/gri/pretty/parser.go b/usr/gri/pretty/parser.go
index b5cbcd72bf99506e6118411f71f9e3f899c0469e..5543d9eeb3261f7a43689098848f8cb11c2df404 100644 (file)
--- a/usr/gri/pretty/parser.go
+++ b/usr/gri/pretty/parser.go
@@ -733,25 +733,21 @@ func (P *Parser) parseStatementList(list *array.Array) {
                defer un(trace(P, "StatementList"));
        }
 
+       expect_semi := false;
        for P.tok != Scanner.CASE && P.tok != Scanner.DEFAULT && P.tok != Scanner.RBRACE && P.tok != Scanner.EOF {
-               s := P.parseStatement();
-               if s != nil {
-                       // not the empty statement
-                       list.Push(s);
+               if expect_semi {
+                       P.expect(Scanner.SEMICOLON);
+                       expect_semi = false;
                }
+               list.Push(P.parseStatement());
                if P.tok == Scanner.SEMICOLON {
                        P.next();
                } else if P.opt_semi {
                        P.opt_semi = false;  // "consume" optional semicolon
                } else {
-                       break;
+                       expect_semi = true;
                }
        }
-
-       // Try to provide a good error message
-       if P.tok != Scanner.CASE && P.tok != Scanner.DEFAULT && P.tok != Scanner.RBRACE && P.tok != Scanner.EOF {
-               P.error(P.pos, "expected end of statement list (semicolon missing?)");
-       }
 }
 
 
@@ -1273,12 +1269,9 @@ func (P *Parser) parseIfStat() *AST.IfStat {
        var else_ AST.Stat;
        if P.tok == Scanner.ELSE {
                P.next();
-               if P.tok == Scanner.IF || P.tok == Scanner.LBRACE {
+               if ok := P.tok == Scanner.IF || P.tok == Scanner.LBRACE; ok || P.sixg {
                        else_ = P.parseStatement();
-               } else if P.sixg {
-                       else_ = P.parseStatement();
-                       if else_ != nil {
-                               // not the empty statement
+                       if !ok {
                                // wrap in a block since we don't have one
                                body := AST.NewBlock(0, Scanner.LBRACE);
                                body.List.Push(else_);
@@ -1290,7 +1283,7 @@ func (P *Parser) parseIfStat() *AST.IfStat {
        }
        P.closeScope();
 
-       return &AST.IfStat{pos, init, cond, body, else_ };
+       return &AST.IfStat{pos, init, cond, body, else_};
 }
 
 
@@ -1438,10 +1431,14 @@ func (P *Parser) parseStatement() AST.Stat {
                return P.parseSwitchStat();
        case Scanner.SELECT:
                return P.parseSelectStat();
+       case Scanner.SEMICOLON:
+               // don't consume the ";", it is the separator following the empty statement
+               return &AST.EmptyStat{P.pos};
        }
 
-       // empty statement
-       return nil;
+       // no statement found
+       P.error(P.pos, "statement expected");
+       return &AST.BadStat{P.pos};
 }
 
 

diff --git a/usr/gri/pretty/printer.go b/usr/gri/pretty/printer.go
index d29bfd1ee6ebcf3a8f4481d0d9b5be2523079ea3..a0de7d06a6b17278469f1aa2120a57acae8c6494 100644 (file)
--- a/usr/gri/pretty/printer.go
+++ b/usr/gri/pretty/printer.go
@@ -919,6 +919,12 @@ func (P *Printer) DoControlFlowStat(s *AST.ControlFlowStat) {
 }
 
 
+func (P *Printer) DoEmptyStat(s *AST.EmptyStat) {
+       P.String(s.Pos, "");
+       P.separator = semicolon;
+}
+
+
 // ----------------------------------------------------------------------------
 // Declarations