C++: handle @try statements in the parser.

No semantic analysis yet, but this prevents the parser from generating
bogus diagnostics.

Task-number: QTCREATORBUG-9309
Change-Id: I2ec575a8474cd51bfa97b17678d3da71ab8dcd7a
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>

src/libs/3rdparty/cplusplus/Parser.cpp

@@ -333,6 +333,7 @@ bool Parser::skipUntilStatement()
             case T_USING:
                 return true;
 
+            case T_AT_TRY:
             case T_AT_SYNCHRONIZED:
                 if (objCEnabled())
                     return true;
@@ -3106,6 +3107,9 @@ bool Parser::parseStatement(StatementAST *&node)
         return true;
     }
 
+    case T_AT_TRY:
+        return objCEnabled() && parseObjCTryStatement(node);
+
     case T_AT_SYNCHRONIZED:
         return objCEnabled() && parseObjCSynchronizedStatement(node);
 
@@ -4404,6 +4408,50 @@ bool Parser::parseObjCStringLiteral(ExpressionAST *&node)
     return true;
 }
 
+///  objc-try-catch-statement:
+///    @try compound-statement objc-catch-list[opt]
+///    @try compound-statement objc-catch-list[opt] @finally compound-statement
+///
+///  objc-catch-list:
+///    @catch ( parameter-declaration ) compound-statement
+///    objc-catch-list @catch ( catch-parameter-declaration ) compound-statement
+///  catch-parameter-declaration:
+///     parameter-declaration
+///     '...' [OBJC2]
+///
+bool Parser::parseObjCTryStatement(StatementAST *& /*node*/)
+{
+    DEBUG_THIS_RULE();
+    if (LA() != T_AT_TRY)
+        return false;
+
+    /*try_token =*/ consumeToken();
+    StatementAST *body_statment;
+    parseCompoundStatement(body_statment);
+    while (LA() == T_AT_CATCH) {
+        /*catch_token =*/ consumeToken();
+        unsigned lparen_token;
+        match(T_LPAREN, &lparen_token);
+        if (LA() == T_DOT_DOT_DOT) {
+            /*unsigned ellipsis_token =*/ consumeToken();
+        } else {
+            ParameterDeclarationAST *exception_decl;
+            parseParameterDeclaration(exception_decl);
+        }
+        unsigned rparen_token;
+        match(T_RPAREN, &rparen_token);
+        StatementAST *catch_statement;
+        parseCompoundStatement(catch_statement);
+    }
+
+    if (LA() == T_AT_FINALLY) {
+        StatementAST *finally_statement;
+        parseCompoundStatement(finally_statement);
+    }
+
+    return true;
+}
+
 bool Parser::parseObjCSynchronizedStatement(StatementAST *&node)
 {
     DEBUG_THIS_RULE();

src/libs/3rdparty/cplusplus/Parser.h

@@ -222,6 +222,7 @@ public:
     bool parseObjCProtocol(DeclarationAST *&node,
                            SpecifierListAST *attributes = 0);
 
+    bool parseObjCTryStatement(StatementAST *&node);
     bool parseObjCSynchronizedStatement(StatementAST *&node);
     bool parseObjCEncodeExpression(ExpressionAST *&node);
     bool parseObjCProtocolExpression(ExpressionAST *&node);

tests/auto/cplusplus/ast/tst_ast.cpp

@@ -159,6 +159,9 @@ private slots:
     void objc_method_attributes_1();
     void objc_selector_error_recovery_1();
     void objc_selector_error_recovery_2();
+    void objc_try_statement_1();
+    void objc_try_statement_2();
+    void objc_try_statement_3();
 
     // expressions with (square) brackets
     void normal_array_access();
@@ -1380,6 +1383,60 @@ void tst_AST::objc_selector_error_recovery_2()
     QVERIFY(ast);
 }
 
+void tst_AST::objc_try_statement_1()
+{
+    QSharedPointer<TranslationUnit> unit(
+                parseDeclaration(
+                    "\n"
+                    "void tst() {\n"
+                    "    @try {\n"
+                    "        something();\n"
+                    "    }\n"
+                    "}\n"
+                    ));
+    AST *ast = unit->ast();
+    QVERIFY(ast);
+    QCOMPARE(diag.errorCount, 0);
+}
+
+void tst_AST::objc_try_statement_2()
+{
+    QSharedPointer<TranslationUnit> unit(
+                parseDeclaration(
+                    "void tst() {\n"
+                    "    @try {\n"
+                    "        something();\n"
+                    "    } @catch (NSException *e) {\n"
+                    "        another_thing();\n"
+                    "    } @catch (UIException *e) { \n"
+                    "        one_more_thing();\n"
+                    "    } @finally {\n"
+                    "        nothing();\n"
+                    "    }\n"
+                    "}\n"
+                    ));
+    AST *ast = unit->ast();
+    QVERIFY(ast);
+    QCOMPARE(diag.errorCount, 0);
+}
+
+void tst_AST::objc_try_statement_3()
+{
+    QSharedPointer<TranslationUnit> unit(
+                parseDeclaration(
+                    "void tst() {\n"
+                    "    @try {\n"
+                    "        get_banana();\n"
+                    "    } @catch (...) {\n"
+                    "        printf(\"Oek?\");\n"
+                    "    }\n"
+                    "}\n"
+                    ));
+    AST *ast = unit->ast();
+    QVERIFY(ast);
+    QCOMPARE(diag.errorCount, 0);
+}
+
 void tst_AST::normal_array_access()
 {
     QSharedPointer<TranslationUnit> unit(parseDeclaration("\n"