Fixed #4953 MySqlStatementParser解析create procedure存储过程时,case when语句处理异常

core/src/main/java/com/alibaba/druid/sql/dialect/mysql/parser/MySqlStatementParser.java

@@ -8942,6 +8942,9 @@ public MySqlCaseStatement parseCase() {
         {
             while (lexer.token() == Token.WHEN) {
                 MySqlWhenStatement when = new MySqlWhenStatement();
+
+                accept(Token.WHEN);
+
                 // when expr
                 when.setCondition(exprParser.expr());
 

core/src/main/java/com/alibaba/druid/sql/dialect/mysql/visitor/MySqlOutputVisitor.java

@@ -4320,7 +4320,9 @@ public boolean visit(SQLIfStatement.Else x) {
     @Override
     public boolean visit(MySqlCaseStatement x) {
         print0(ucase ? "CASE " : "case ");
-        x.getCondition().accept(this);
+        if (x.getCondition() != null) {
+            x.getCondition().accept(this);
+        }
         println();
         for (int i = 0; i < x.getWhenList().size(); i++) {
             x.getWhenList().get(i).accept(this);

core/src/test/java/com/alibaba/druid/bvt/sql/mysql/create/MySqlCreateProcedureTest16.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.druid.bvt.sql.mysql.create;
+
+import com.alibaba.druid.sql.MysqlTest;
+import com.alibaba.druid.sql.SQLUtils;
+import com.alibaba.druid.sql.ast.SQLStatement;
+import com.alibaba.druid.sql.dialect.mysql.parser.MySqlStatementParser;
+import com.alibaba.druid.sql.visitor.SchemaStatVisitor;
+import com.alibaba.druid.util.JdbcConstants;
+
+public class MySqlCreateProcedureTest16 extends MysqlTest {
+
+    public void test_0() {
+        String sql = "CREATE PROCEDURE drop_tab_index (IN db varchar(50),IN tb_name varchar(512),IN idx_type varchar(50),IN idx_name varchar(512))\n" +
+                "BEGIN\n" +
+                "    CASE \n" +
+                "        WHEN idx_type='PRIMARY' OR idx_type='primary' THEN\n" +
+                "            IF EXISTS(SELECT * FROM INFORMATION_SCHEMA.STATISTICS WHERE TABLE_SCHEMA=db AND table_name=tb_name AND INDEX_NAME='PRIMARY') THEN\n" +
+                "                SET @alter_sql=concat(\"ALTER TABLE \",db,\".\",tb_name,\" DROP PRIMARY KEY\");\n" +
+                "                prepare stmt from @alter_sql;\n" +
+                "                execute stmt;\n" +
+                "                SELECT @alter_sql;\n" +
+                "            END IF;\n" +
+                "        WHEN idx_type='UNIQUE' OR idx_type='unique' THEN\n" +
+                "            IF EXISTS(SELECT * FROM INFORMATION_SCHEMA.STATISTICS WHERE TABLE_SCHEMA=db AND table_name=tb_name AND INDEX_NAME=idx_name) THEN\n" +
+                "                SET @alter_sql=concat(\"ALTER TABLE \",db,\".\",tb_name,\" DROP KEY \",idx_name);\n" +
+                "                prepare stmt from @alter_sql;\n" +
+                "                execute stmt;\n" +
+                "                SELECT @alter_sql;\n" +
+                "            END IF;\n" +
+                "        WHEN idx_type='SECONDARY' OR idx_type='secondary' THEN\n" +
+                "            IF EXISTS(SELECT * FROM INFORMATION_SCHEMA.STATISTICS WHERE TABLE_SCHEMA=db AND table_name=tb_name AND INDEX_NAME=idx_name) THEN\n" +
+                "                SET @alter_sql=concat(\"ALTER TABLE \",db,\".\",tb_name,\" DROP KEY \",idx_name);\n" +
+                "                prepare stmt from @alter_sql;\n" +
+                "                execute stmt;\n" +
+                "                SELECT @alter_sql;\n" +
+                "            END IF;\n" +
+                "    END CASE;\n" +
+                "END;;";
+        MySqlStatementParser parser = new MySqlStatementParser(sql);
+        SQLStatement stmt = parser.parseStatement();
+        System.out.println(SQLUtils.toMySqlString(stmt));
+        SchemaStatVisitor visitor = SQLUtils.createSchemaStatVisitor(JdbcConstants.MYSQL);
+        stmt.accept(visitor);
+        assertEquals(3, visitor.getConditions().size());
+    }
+}