feat: FlinkSQL supports auto complete (#115)

* feat: add antlr4-c3 dependencies

* feat: distinguish table, catalog and database from uid

* feat: move semicolon from sqlStatements to sqlStatement

* chore: move antlr4ts-cli to devDependencies

* feat: improve basic parser and support suggestions of token and syntax

* feat: implement suggest method in sql parsers

* test: flink sql suggestion test cases

* feat: optimize ts defination of suggestion

* feat: add split listener and optimize performance of auto-completion

* test: supplementary flink suggestion unit tests

package.json

@@ -34,6 +34,7 @@
     "@types/node": "^18.15.11",
     "@typescript-eslint/eslint-plugin": "^3.10.1",
     "@typescript-eslint/parser": "^3.10.1",
+    "antlr4ts-cli": "^0.5.0-alpha.4",
     "eslint": "^7.32.0",
     "eslint-config-google": "^0.14.0",
     "jest": "^29.5.0",
@@ -47,7 +48,7 @@
     "registry": "https://registry.npmjs.org/"
   },
   "dependencies": {
-    "antlr4ts": "^0.5.0-alpha.4",
+    "antlr4-c3": "^3.0.1",
-    "antlr4ts-cli": "^0.5.0-alpha.4"
+    "antlr4ts": "^0.5.0-alpha.4"
   }
 }

pnpm-lock.yaml

@@ -1,4 +1,4 @@
-lockfileVersion: 5.4
+lockfileVersion: 5.3
 
 specifiers:
   '@swc/core': ^1.3.60
@@ -7,6 +7,7 @@ specifiers:
   '@types/node': ^18.15.11
   '@typescript-eslint/eslint-plugin': ^3.10.1
   '@typescript-eslint/parser': ^3.10.1
+  antlr4-c3: ^3.0.1
   antlr4ts: ^0.5.0-alpha.4
   antlr4ts-cli: ^0.5.0-alpha.4
   eslint: ^7.32.0
@@ -17,16 +18,17 @@ specifiers:
   yargs-parser: ^21.1.1
 
 dependencies:
+  antlr4-c3: 3.0.1
   antlr4ts: 0.5.0-alpha.4
-  antlr4ts-cli: 0.5.0-alpha.4
 
 devDependencies:
   '@swc/core': 1.3.60
   '@swc/jest': 0.2.26_@swc+core@1.3.60
   '@types/jest': 29.5.1
   '@types/node': 18.16.16
-  '@typescript-eslint/eslint-plugin': 3.10.1_ughicqazzfm5kkseraofkm6oci
+  '@typescript-eslint/eslint-plugin': 3.10.1_a18e814019c959d52a44881c5533ce12
-  '@typescript-eslint/parser': 3.10.1_cgdknpc562nnyruteofhkegnom
+  '@typescript-eslint/parser': 3.10.1_eslint@7.32.0+typescript@5.0.4
+  antlr4ts-cli: 0.5.0-alpha.4
   eslint: 7.32.0
   eslint-config-google: 0.14.0_eslint@7.32.0
   jest: 29.5.0_@types+node@18.16.16
@@ -942,7 +944,7 @@ packages:
       '@types/yargs-parser': 21.0.0
     dev: true
 
-  /@typescript-eslint/eslint-plugin/3.10.1_ughicqazzfm5kkseraofkm6oci:
+  /@typescript-eslint/eslint-plugin/3.10.1_a18e814019c959d52a44881c5533ce12:
     resolution: {integrity: sha512-PQg0emRtzZFWq6PxBcdxRH3QIQiyFO3WCVpRL3fgj5oQS3CDs3AeAKfv4DxNhzn8ITdNJGJ4D3Qw8eAJf3lXeQ==}
     engines: {node: ^10.12.0 || >=12.0.0}
     peerDependencies:
@@ -953,8 +955,8 @@ packages:
       typescript:
         optional: true
     dependencies:
-      '@typescript-eslint/experimental-utils': 3.10.1_cgdknpc562nnyruteofhkegnom
+      '@typescript-eslint/experimental-utils': 3.10.1_eslint@7.32.0+typescript@5.0.4
-      '@typescript-eslint/parser': 3.10.1_cgdknpc562nnyruteofhkegnom
+      '@typescript-eslint/parser': 3.10.1_eslint@7.32.0+typescript@5.0.4
       debug: 4.3.4
       eslint: 7.32.0
       functional-red-black-tree: 1.0.1
@@ -966,7 +968,7 @@ packages:
       - supports-color
     dev: true
 
-  /@typescript-eslint/experimental-utils/3.10.1_cgdknpc562nnyruteofhkegnom:
+  /@typescript-eslint/experimental-utils/3.10.1_eslint@7.32.0+typescript@5.0.4:
     resolution: {integrity: sha512-DewqIgscDzmAfd5nOGe4zm6Bl7PKtMG2Ad0KG8CUZAHlXfAKTF9Ol5PXhiMh39yRL2ChRH1cuuUGOcVyyrhQIw==}
     engines: {node: ^10.12.0 || >=12.0.0}
     peerDependencies:
@@ -983,7 +985,7 @@ packages:
       - typescript
     dev: true
 
-  /@typescript-eslint/parser/3.10.1_cgdknpc562nnyruteofhkegnom:
+  /@typescript-eslint/parser/3.10.1_eslint@7.32.0+typescript@5.0.4:
     resolution: {integrity: sha512-Ug1RcWcrJP02hmtaXVS3axPPTTPnZjupqhgj+NnZ6BCkwSImWk/283347+x9wN+lqOdK9Eo3vsyiyDHgsmiEJw==}
     engines: {node: ^10.12.0 || >=12.0.0}
     peerDependencies:
@@ -994,7 +996,7 @@ packages:
         optional: true
     dependencies:
       '@types/eslint-visitor-keys': 1.0.0
-      '@typescript-eslint/experimental-utils': 3.10.1_cgdknpc562nnyruteofhkegnom
+      '@typescript-eslint/experimental-utils': 3.10.1_eslint@7.32.0+typescript@5.0.4
       '@typescript-eslint/types': 3.10.1
       '@typescript-eslint/typescript-estree': 3.10.1_typescript@5.0.4
       eslint: 7.32.0
@@ -1118,10 +1120,16 @@ packages:
     engines: {node: '>=10'}
     dev: true
 
+  /antlr4-c3/3.0.1:
+    resolution: {integrity: sha512-Vbizas0WK4Id6l1f48ANYHFZgfzmj82LZx4OuB/a87vCpyoUwofrlJ+sCiL1qT/D2SWf8HEcBPCsgskdx8NnzQ==}
+    dependencies:
+      antlr4ts: 0.5.0-alpha.4
+    dev: false
+
   /antlr4ts-cli/0.5.0-alpha.4:
     resolution: {integrity: sha512-lVPVBTA2CVHRYILSKilL6Jd4hAumhSZZWA7UbQNQrmaSSj7dPmmYaN4bOmZG79cOy0lS00i4LY68JZZjZMWVrw==}
     hasBin: true
-    dev: false
+    dev: true
 
   /antlr4ts/0.5.0-alpha.4:
     resolution: {integrity: sha512-WPQDt1B74OfPv/IMS2ekXAKkTZIHl88uMetg6q3OTqgFxZ/dxDXI0EWLyZid/1Pe6hTftyg5N7gel5wNAGxXyQ==}
@@ -1535,8 +1543,8 @@ packages:
     engines: {node: '>=10'}
     hasBin: true
     dependencies:
-      JSONStream: 1.3.5
       is-text-path: 1.0.1
+      JSONStream: 1.3.5
       lodash: 4.17.21
       meow: 8.1.2
       split2: 3.2.2

src/grammar/flinksql/FlinkSqlParser.g4

@@ -9,12 +9,14 @@ statement
     ;
 
 sqlStatements
-    : (sqlStatement SEMICOLON? | emptyStatement)*
+    : (sqlStatement | emptyStatement)*
     ;
 
 sqlStatement
-    : ddlStatement | dmlStatement | describeStatement | explainStatement | useStatement | showStatememt
+    : ddlStatement SEMICOLON? | dmlStatement SEMICOLON? | describeStatement SEMICOLON? 
-    | loadStatement | unloadStatememt | setStatememt | resetStatememt | jarStatememt | dtAddStatement
+    | explainStatement SEMICOLON? | useStatement SEMICOLON?| showStatememt SEMICOLON?
+    | loadStatement SEMICOLON?| unloadStatememt SEMICOLON?| setStatememt SEMICOLON?
+    | resetStatememt SEMICOLON?| jarStatememt SEMICOLON?| dtAddStatement SEMICOLON?
     ;
 
 emptyStatement
@@ -33,7 +35,7 @@ dmlStatement
 
 // some statemen
 describeStatement
-    : (KW_DESCRIBE | KW_DESC) uid
+    : (KW_DESCRIBE | KW_DESC) tablePath
     ;
 
 explainStatement
@@ -49,7 +51,9 @@ explainDetail
     ;
 
 useStatement
-    : KW_USE KW_CATALOG? uid | useModuleStatement
+    : KW_USE KW_CATALOG catalogPath 
+    | KW_USE databasePath
+    | useModuleStatement
     ;
 
 useModuleStatement
@@ -59,7 +63,7 @@ useModuleStatement
 showStatememt
     : KW_SHOW (KW_CATALOGS | KW_DATABASES | KW_VIEWS | KW_JARS)
     | KW_SHOW KW_CURRENT (KW_CATALOG | KW_DATABASE)
-    | KW_SHOW KW_TABLES (( KW_FROM | KW_IN ) uid)? likePredicate?
+    | KW_SHOW KW_TABLES (( KW_FROM | KW_IN ) tablePath)? likePredicate?
     | KW_SHOW KW_COLUMNS ( KW_FROM | KW_IN ) uid likePredicate?
     | KW_SHOW KW_CREATE (KW_TABLE | KW_VIEW) uid
     | KW_SHOW KW_USER? KW_FUNCTIONS
@@ -106,7 +110,7 @@ createTable
     ;
     
 simpleCreateTable
-    : KW_CREATE KW_TEMPORARY? KW_TABLE ifNotExists? sourceTable
+    : KW_CREATE KW_TEMPORARY? KW_TABLE ifNotExists? tablePathCreate
     LR_BRACKET 
         columnOptionDefinition (COMMA columnOptionDefinition)*
         (COMMA watermarkDefinition)?
@@ -124,7 +128,7 @@ simpleCreateTable
  * CTAS 不支持指定显示指定列，不支持创建分区表，临时表
  */
 createTableAsSelect
-    : KW_CREATE KW_TABLE ifNotExists? sourceTable withOption (KW_AS queryStatement)?
+    : KW_CREATE KW_TABLE ifNotExists? tablePathCreate withOption (KW_AS queryStatement)?
     ;
 
 columnOptionDefinition
@@ -244,11 +248,7 @@ transformArgument
     ;
 
 likeDefinition
-    : KW_LIKE sourceTable (LR_BRACKET likeOption* RR_BRACKET)?
+    : KW_LIKE tablePath (LR_BRACKET likeOption* RR_BRACKET)?
-    ;
-
-sourceTable
-    : uid
     ;
 
 likeOption
@@ -261,7 +261,7 @@ createCatalog
     ;
 
 createDatabase
-    : KW_CREATE KW_DATABASE ifNotExists? uid commentSpec? withOption
+    : KW_CREATE KW_DATABASE ifNotExists? databasePathCreate commentSpec? withOption
     ;
 
 createView
@@ -269,7 +269,7 @@ createView
     ;
 
 createFunction
-    : KW_CREATE (KW_TEMPORARY|KW_TEMPORARY KW_SYSTEM)? KW_FUNCTION ifNotExists? uid KW_AS identifier (KW_LANGUAGE (KW_JAVA|KW_SCALA|KW_PYTHON))? usingClause?
+    : KW_CREATE (KW_TEMPORARY|KW_TEMPORARY KW_SYSTEM)? KW_FUNCTION ifNotExists? functionName KW_AS identifier (KW_LANGUAGE (KW_JAVA|KW_SCALA|KW_PYTHON))? usingClause?
     ;
 
 usingClause
@@ -285,7 +285,7 @@ jarFileName
 // it only includes rename, set key, add constraint, drop constraint, add unique
 
 alterTable
-    : KW_ALTER KW_TABLE ifExists? uid (renameDefinition | setKeyValueDefinition | addConstraint | dropConstraint | addUnique)
+    : KW_ALTER KW_TABLE ifExists? tablePath (renameDefinition | setKeyValueDefinition | addConstraint | dropConstraint | addUnique)
     ;
 
 renameDefinition
@@ -317,7 +317,7 @@ alertView
     ;
 
 alterDatabase
-    : KW_ALTER KW_DATABASE uid setKeyValueDefinition
+    : KW_ALTER KW_DATABASE databasePath setKeyValueDefinition
     ;
 
 alterFunction
@@ -328,15 +328,15 @@ alterFunction
 // Drop statements
 
 dropCatalog
-    : KW_DROP KW_CATALOG ifExists? uid
+    : KW_DROP KW_CATALOG ifExists? catalogPath
     ;
 
 dropTable
-    : KW_DROP KW_TEMPORARY? KW_TABLE ifExists? uid
+    : KW_DROP KW_TEMPORARY? KW_TABLE ifExists? tablePath
     ;
 
 dropDatabase
-    : KW_DROP KW_DATABASE ifExists? uid dropType=(KW_RESTRICT | KW_CASCADE)?
+    : KW_DROP KW_DATABASE ifExists? databasePath dropType=(KW_RESTRICT | KW_CASCADE)?
     ;
 
 dropView
@@ -344,7 +344,7 @@ dropView
     ;
 
 dropFunction
-    : KW_DROP (KW_TEMPORARY|KW_TEMPORARY KW_SYSTEM)? KW_FUNCTION ifExists? uid
+    : KW_DROP (KW_TEMPORARY|KW_TEMPORARY KW_SYSTEM)? KW_FUNCTION ifExists? functionName
     ;
 
 
@@ -356,7 +356,7 @@ insertStatement
     ;
 
 insertSimpleStatement
-    : KW_INSERT (KW_INTO | KW_OVERWRITE) uid
+    : KW_INSERT (KW_INTO | KW_OVERWRITE) tablePath
     (
         insertPartitionDefinition? columnNameList? queryStatement
         | valuesDefinition
@@ -454,9 +454,7 @@ tablePrimary
     | KW_UNNEST LR_BRACKET expression RR_BRACKET
     ;
 
-tablePath
+
-    : uid
-    ;
 
 systemTimePeriod
     : KW_FOR KW_SYSTEM_TIME KW_AS KW_OF dateTimeExpression
@@ -827,6 +825,26 @@ whenClause
     : KW_WHEN condition=expression KW_THEN result=expression
     ;
 
+catalogPath
+    : uid
+    ;
+
+databasePath
+    : uid
+    ;
+
+databasePathCreate
+    : uid
+    ;
+
+tablePathCreate
+    : uid
+    ;
+
+tablePath
+    : uid
+    ;
+
 uid
     : identifier (DOT identifier)*?
     ;

src/index.ts

@@ -14,3 +14,6 @@ export * from './lib/pgsql/PostgreSQLParserListener';
 export * from './lib/pgsql/PostgreSQLParserVisitor';
 export * from './lib/trinosql/TrinoSqlListener';
 export * from './lib/trinosql/TrinoSqlVisitor';
+
+export type * from './parser/common/basic-parser-types';
+export type { SyntaxError, ParserError } from './parser/common/parserErrorListener';

src/lib/flinksql/FlinkSqlLexer.ts

@@ -1,4 +1,4 @@
-// Generated from /Users/ziv/github.com/dt-sql-parser/src/grammar/flinksql/FlinkSqlLexer.g4 by ANTLR 4.9.0-SNAPSHOT
+// Generated from /Users/hayden/Desktop/dt-works/dt-sql-parser/src/grammar/flinksql/FlinkSqlLexer.g4 by ANTLR 4.9.0-SNAPSHOT
 
 
 import { ATN } from "antlr4ts/atn/ATN";

src/lib/flinksql/FlinkSqlParserListener.ts

@@ -1,4 +1,4 @@
-// Generated from /Users/ziv/github.com/dt-sql-parser/src/grammar/flinksql/FlinkSqlParser.g4 by ANTLR 4.9.0-SNAPSHOT
+// Generated from /Users/hayden/Desktop/dt-works/dt-sql-parser/src/grammar/flinksql/FlinkSqlParser.g4 by ANTLR 4.9.0-SNAPSHOT
 
 
 import { ParseTreeListener } from "antlr4ts/tree/ParseTreeListener";
@@ -84,7 +84,6 @@ import { TransformListContext } from "./FlinkSqlParser";
 import { TransformContext } from "./FlinkSqlParser";
 import { TransformArgumentContext } from "./FlinkSqlParser";
 import { LikeDefinitionContext } from "./FlinkSqlParser";
-import { SourceTableContext } from "./FlinkSqlParser";
 import { LikeOptionContext } from "./FlinkSqlParser";
 import { CreateCatalogContext } from "./FlinkSqlParser";
 import { CreateDatabaseContext } from "./FlinkSqlParser";
@@ -127,7 +126,6 @@ import { FromClauseContext } from "./FlinkSqlParser";
 import { TableExpressionContext } from "./FlinkSqlParser";
 import { TableReferenceContext } from "./FlinkSqlParser";
 import { TablePrimaryContext } from "./FlinkSqlParser";
-import { TablePathContext } from "./FlinkSqlParser";
 import { SystemTimePeriodContext } from "./FlinkSqlParser";
 import { DateTimeExpressionContext } from "./FlinkSqlParser";
 import { InlineDataValueClauseContext } from "./FlinkSqlParser";
@@ -192,6 +190,11 @@ import { IdentifierContext } from "./FlinkSqlParser";
 import { UnquotedIdentifierContext } from "./FlinkSqlParser";
 import { QuotedIdentifierContext } from "./FlinkSqlParser";
 import { WhenClauseContext } from "./FlinkSqlParser";
+import { CatalogPathContext } from "./FlinkSqlParser";
+import { DatabasePathContext } from "./FlinkSqlParser";
+import { DatabasePathCreateContext } from "./FlinkSqlParser";
+import { TablePathCreateContext } from "./FlinkSqlParser";
+import { TablePathContext } from "./FlinkSqlParser";
 import { UidContext } from "./FlinkSqlParser";
 import { WithOptionContext } from "./FlinkSqlParser";
 import { IfNotExistsContext } from "./FlinkSqlParser";
@@ -1177,17 +1180,6 @@ export interface FlinkSqlParserListener extends ParseTreeListener {
 	 */
 	exitLikeDefinition?: (ctx: LikeDefinitionContext) => void;
 
-	/**
-	 * Enter a parse tree produced by `FlinkSqlParser.sourceTable`.
-	 * @param ctx the parse tree
-	 */
-	enterSourceTable?: (ctx: SourceTableContext) => void;
-	/**
-	 * Exit a parse tree produced by `FlinkSqlParser.sourceTable`.
-	 * @param ctx the parse tree
-	 */
-	exitSourceTable?: (ctx: SourceTableContext) => void;
-
 	/**
 	 * Enter a parse tree produced by `FlinkSqlParser.likeOption`.
 	 * @param ctx the parse tree
@@ -1650,17 +1642,6 @@ export interface FlinkSqlParserListener extends ParseTreeListener {
 	 */
 	exitTablePrimary?: (ctx: TablePrimaryContext) => void;
 
-	/**
-	 * Enter a parse tree produced by `FlinkSqlParser.tablePath`.
-	 * @param ctx the parse tree
-	 */
-	enterTablePath?: (ctx: TablePathContext) => void;
-	/**
-	 * Exit a parse tree produced by `FlinkSqlParser.tablePath`.
-	 * @param ctx the parse tree
-	 */
-	exitTablePath?: (ctx: TablePathContext) => void;
-
 	/**
 	 * Enter a parse tree produced by `FlinkSqlParser.systemTimePeriod`.
 	 * @param ctx the parse tree
@@ -2365,6 +2346,61 @@ export interface FlinkSqlParserListener extends ParseTreeListener {
 	 */
 	exitWhenClause?: (ctx: WhenClauseContext) => void;
 
+	/**
+	 * Enter a parse tree produced by `FlinkSqlParser.catalogPath`.
+	 * @param ctx the parse tree
+	 */
+	enterCatalogPath?: (ctx: CatalogPathContext) => void;
+	/**
+	 * Exit a parse tree produced by `FlinkSqlParser.catalogPath`.
+	 * @param ctx the parse tree
+	 */
+	exitCatalogPath?: (ctx: CatalogPathContext) => void;
+
+	/**
+	 * Enter a parse tree produced by `FlinkSqlParser.databasePath`.
+	 * @param ctx the parse tree
+	 */
+	enterDatabasePath?: (ctx: DatabasePathContext) => void;
+	/**
+	 * Exit a parse tree produced by `FlinkSqlParser.databasePath`.
+	 * @param ctx the parse tree
+	 */
+	exitDatabasePath?: (ctx: DatabasePathContext) => void;
+
+	/**
+	 * Enter a parse tree produced by `FlinkSqlParser.databasePathCreate`.
+	 * @param ctx the parse tree
+	 */
+	enterDatabasePathCreate?: (ctx: DatabasePathCreateContext) => void;
+	/**
+	 * Exit a parse tree produced by `FlinkSqlParser.databasePathCreate`.
+	 * @param ctx the parse tree
+	 */
+	exitDatabasePathCreate?: (ctx: DatabasePathCreateContext) => void;
+
+	/**
+	 * Enter a parse tree produced by `FlinkSqlParser.tablePathCreate`.
+	 * @param ctx the parse tree
+	 */
+	enterTablePathCreate?: (ctx: TablePathCreateContext) => void;
+	/**
+	 * Exit a parse tree produced by `FlinkSqlParser.tablePathCreate`.
+	 * @param ctx the parse tree
+	 */
+	exitTablePathCreate?: (ctx: TablePathCreateContext) => void;
+
+	/**
+	 * Enter a parse tree produced by `FlinkSqlParser.tablePath`.
+	 * @param ctx the parse tree
+	 */
+	enterTablePath?: (ctx: TablePathContext) => void;
+	/**
+	 * Exit a parse tree produced by `FlinkSqlParser.tablePath`.
+	 * @param ctx the parse tree
+	 */
+	exitTablePath?: (ctx: TablePathContext) => void;
+
 	/**
 	 * Enter a parse tree produced by `FlinkSqlParser.uid`.
 	 * @param ctx the parse tree

src/lib/flinksql/FlinkSqlParserVisitor.ts

@@ -1,4 +1,4 @@
-// Generated from /Users/ziv/github.com/dt-sql-parser/src/grammar/flinksql/FlinkSqlParser.g4 by ANTLR 4.9.0-SNAPSHOT
+// Generated from /Users/hayden/Desktop/dt-works/dt-sql-parser/src/grammar/flinksql/FlinkSqlParser.g4 by ANTLR 4.9.0-SNAPSHOT
 
 
 import { ParseTreeVisitor } from "antlr4ts/tree/ParseTreeVisitor";
@@ -84,7 +84,6 @@ import { TransformListContext } from "./FlinkSqlParser";
 import { TransformContext } from "./FlinkSqlParser";
 import { TransformArgumentContext } from "./FlinkSqlParser";
 import { LikeDefinitionContext } from "./FlinkSqlParser";
-import { SourceTableContext } from "./FlinkSqlParser";
 import { LikeOptionContext } from "./FlinkSqlParser";
 import { CreateCatalogContext } from "./FlinkSqlParser";
 import { CreateDatabaseContext } from "./FlinkSqlParser";
@@ -127,7 +126,6 @@ import { FromClauseContext } from "./FlinkSqlParser";
 import { TableExpressionContext } from "./FlinkSqlParser";
 import { TableReferenceContext } from "./FlinkSqlParser";
 import { TablePrimaryContext } from "./FlinkSqlParser";
-import { TablePathContext } from "./FlinkSqlParser";
 import { SystemTimePeriodContext } from "./FlinkSqlParser";
 import { DateTimeExpressionContext } from "./FlinkSqlParser";
 import { InlineDataValueClauseContext } from "./FlinkSqlParser";
@@ -192,6 +190,11 @@ import { IdentifierContext } from "./FlinkSqlParser";
 import { UnquotedIdentifierContext } from "./FlinkSqlParser";
 import { QuotedIdentifierContext } from "./FlinkSqlParser";
 import { WhenClauseContext } from "./FlinkSqlParser";
+import { CatalogPathContext } from "./FlinkSqlParser";
+import { DatabasePathContext } from "./FlinkSqlParser";
+import { DatabasePathCreateContext } from "./FlinkSqlParser";
+import { TablePathCreateContext } from "./FlinkSqlParser";
+import { TablePathContext } from "./FlinkSqlParser";
 import { UidContext } from "./FlinkSqlParser";
 import { WithOptionContext } from "./FlinkSqlParser";
 import { IfNotExistsContext } from "./FlinkSqlParser";
@@ -825,13 +828,6 @@ export interface FlinkSqlParserVisitor<Result> extends ParseTreeVisitor<Result>
 	 */
 	visitLikeDefinition?: (ctx: LikeDefinitionContext) => Result;
 
-	/**
-	 * Visit a parse tree produced by `FlinkSqlParser.sourceTable`.
-	 * @param ctx the parse tree
-	 * @return the visitor result
-	 */
-	visitSourceTable?: (ctx: SourceTableContext) => Result;
-
 	/**
 	 * Visit a parse tree produced by `FlinkSqlParser.likeOption`.
 	 * @param ctx the parse tree
@@ -1126,13 +1122,6 @@ export interface FlinkSqlParserVisitor<Result> extends ParseTreeVisitor<Result>
 	 */
 	visitTablePrimary?: (ctx: TablePrimaryContext) => Result;
 
-	/**
-	 * Visit a parse tree produced by `FlinkSqlParser.tablePath`.
-	 * @param ctx the parse tree
-	 * @return the visitor result
-	 */
-	visitTablePath?: (ctx: TablePathContext) => Result;
-
 	/**
 	 * Visit a parse tree produced by `FlinkSqlParser.systemTimePeriod`.
 	 * @param ctx the parse tree
@@ -1581,6 +1570,41 @@ export interface FlinkSqlParserVisitor<Result> extends ParseTreeVisitor<Result>
 	 */
 	visitWhenClause?: (ctx: WhenClauseContext) => Result;
 
+	/**
+	 * Visit a parse tree produced by `FlinkSqlParser.catalogPath`.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	visitCatalogPath?: (ctx: CatalogPathContext) => Result;
+
+	/**
+	 * Visit a parse tree produced by `FlinkSqlParser.databasePath`.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	visitDatabasePath?: (ctx: DatabasePathContext) => Result;
+
+	/**
+	 * Visit a parse tree produced by `FlinkSqlParser.databasePathCreate`.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	visitDatabasePathCreate?: (ctx: DatabasePathCreateContext) => Result;
+
+	/**
+	 * Visit a parse tree produced by `FlinkSqlParser.tablePathCreate`.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	visitTablePathCreate?: (ctx: TablePathCreateContext) => Result;
+
+	/**
+	 * Visit a parse tree produced by `FlinkSqlParser.tablePath`.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	visitTablePath?: (ctx: TablePathContext) => Result;
+
 	/**
 	 * Visit a parse tree produced by `FlinkSqlParser.uid`.
 	 * @param ctx the parse tree

src/parser/common/basic-parser-types.ts

@@ -0,0 +1,71 @@
+/**
+ * The insertion position of the candidate list.
+ * Such as cursor position
+ */
+export interface CaretPosition {
+    /** start at 1 */
+    lineNumber: number;
+    /** start at 1 */
+    column: number;
+}
+
+/**
+ * Syntax context type at caret position
+ */
+export enum SyntaxContextType {
+    /** catalog name */
+    CATALOG = 'catalog',
+    /** database name path, such as catalog.db */
+    DATABASE = 'database',
+    /** database name path will be created  */
+    DATABASE_CREATE = 'databaseCreate',
+    /** table name path, such as catalog.db.tb */
+    TABLE = 'table',
+    /** table name path will be created */
+    TABLE_CREATE = 'tableCreate'
+}
+
+export interface WordRange {
+    /** content of word */
+    text: string;
+    /** start at 0 */
+    startIndex: number;
+    stopIndex: number;
+    /** start at 1 */
+    line: number;
+    /** start at 1 */
+    startColumn: number;
+    stopColumn: number;
+}
+
+/**
+ * Suggested information analyzed from the input
+ */
+export interface SyntaxSuggestion<T = WordRange> {
+    syntaxContextType: SyntaxContextType;
+    wordRanges: T[];
+}
+
+/**
+ * Suggested information analyzed from the input
+ */
+export interface Suggestions<T = WordRange> {
+    /**
+     * Suggestions about syntax
+     */
+    syntax: SyntaxSuggestion<T>[];
+    /**
+     * Suggestions about keywords
+     */
+    keywords: string[];
+}
+
+export interface TextSlice {
+    startIndex: number;
+    endIndex: number;
+    startLine: number;
+    endLine: number;
+    startColumn: number;
+    endColumn: number;
+    text: string;
+}

src/parser/common/basicParser.ts

@@ -1,86 +1,164 @@
-import { Parser } from 'antlr4ts';
+import { 
-import { ParseTreeWalker } from 'antlr4ts/tree';
+    Parser, 
-
+    Lexer, 
+    Token,
+    CharStreams, 
+    CommonTokenStream, 
+    CodePointCharStream,
+    ParserRuleContext
+} from 'antlr4ts';
+import { ParseTreeWalker, ParseTreeListener } from 'antlr4ts/tree';
+import { CandidatesCollection, CodeCompletionCore } from 'antlr4-c3';
+import { findCaretTokenIndex } from '../../utils/findCaretTokenIndex';
+import { 
+    CaretPosition,
+    Suggestions,
+    SyntaxSuggestion,
+    WordRange,
+    TextSlice
+} from './basic-parser-types';
 import ParserErrorListener, {
     ParserError,
     ErrorHandler,
     ParserErrorCollector,
 } from './parserErrorListener';
 
-interface IParser extends Parser {
+interface IParser<IParserRuleContext extends ParserRuleContext> extends Parser {
-    // Lost in type definition
-    ruleNames: string[];
     // Customized in our parser
-    program(): any;
+    program(): IParserRuleContext;
+}
+
+interface SplitListener extends ParseTreeListener {
+    statementsContext: ParserRuleContext[];
 }
 
 /**
  * Custom Parser class, subclass needs extends it.
  */
-export default abstract class BasicParser {
+export default abstract class BasicParser<
-    private _parser: IParser;
+    L extends Lexer = Lexer, 
-
+    PRC extends ParserRuleContext = ParserRuleContext,
-    public parse(
+    P extends IParser<PRC> = IParser<PRC>
-        input: string,
+>  {
-        errorListener?: ErrorHandler<any>,
+    protected _charStreams: CodePointCharStream;
-    ) {
+    protected _lexer: L;
-        const parser = this.createParser(input);
+    protected _tokenStream: CommonTokenStream;
-        this._parser = parser;
+    protected _parser: P;
-
+    protected _parserTree: PRC;
-        parser.removeErrorListeners();
+    protected _errorCollector: ParserErrorCollector = new ParserErrorCollector();
-        parser.addErrorListener(new ParserErrorListener(errorListener));
+    protected _parsedInput: string = null;
-
-        const parserTree = parser.program();
-
-        return parserTree;
-    }
-
-    public validate(input: string): ParserError[] {
-        const lexerError = []; const syntaxErrors = [];
-
-        const parser = this.createParser(input);
-        this._parser = parser;
-
-        parser.removeErrorListeners();
-        parser.addErrorListener(new ParserErrorCollector(syntaxErrors));
-
-        parser.program();
-        return lexerError.concat(syntaxErrors);
-    }
 
     /**
-     * Create antrl4 Lexer object
+     * preferredRules for antlr4-c3
+     */
+    public abstract preferredRules: Set<number>;
+ 
+    /**
+     * Create antrl4 Lexer instance
      * @param input source string
      */
-    public abstract createLexer(input: string);
+    public abstract createLexerFormCharStream(charStreams: CodePointCharStream): L;
 
     /**
-     * Create Parser by lexer
+     * Create Parser by CommonTokenStream
-     * @param lexer Lexer
+     * @param tokenStream CommonTokenStream
      */
-    public abstract createParserFromLexer(lexer);
+    public abstract createParserFromTokenStream(tokenStream: CommonTokenStream): P;
+    
+    /**
+     * convert candidates to suggestions
+     * @param candidates candidate list
+     * @param allTokens all tokens from input
+     * @param caretTokenIndex tokenIndex of caretPosition
+     * @param tokenIndexOffset offset of the tokenIndex in the candidates 
+     * compared to the tokenIndex in allTokens
+     */
+    public abstract processCandidates(
+        candidates: CandidatesCollection, 
+        allTokens: Token[], 
+        caretTokenIndex: number,
+        tokenIndexOffset: number,
+    ): Suggestions<Token>;
 
     /**
-     * Get all Tokens of input string
+     * splitListener instance Getter
-     * @param input string
+     */
+    protected abstract get splitListener (): SplitListener; 
+
+    /**
+     * If it is invoked multiple times in a row and the input parameters is the same 
+     * this method returns the parsing result directly for the first time，
+     * unless the errorListener parameter is passed
+     * @param input source string
+     * @param errorListener listen errors
+     * @returns parserTree
+     */
+    public parse(
+        input: string,
+        errorListener?: ErrorHandler<any>
+    ) {
+        // Avoid parsing the same input repeatedly
+        if(this._parsedInput === input && !errorListener) {
+            return;
+        }
+
+        const parser = this.createParser(input);
+        this._parsedInput = input;
+
+        parser.removeErrorListeners();
+        this._errorCollector.clear();
+
+        parser.addErrorListener(this._errorCollector);
+        if(errorListener) {
+            parser.addErrorListener(new ParserErrorListener(errorListener));
+        }
+
+        this._parserTree = parser.program();
+        
+        return this._parserTree;
+    }
+
+    /**
+     * validate input string and return syntax errors
+     * @param input source string
+     * @returns syntax errors
+     */
+    public validate(input: string): ParserError[] {
+        this.parse(input);
+        const lexerError = [];
+        return lexerError.concat(this._errorCollector.parserErrors);
+    }
+
+    /**
+     * Get all Tokens of input string，'<EOF>' is not included
+     * @param input source string
      * @returns Token[]
      */
-    public getAllTokens(input: string): string[] {
+    public getAllTokens(input: string): Token[] {
-        const lexer = this.createLexer(input);
+        this.parse(input);
-        return lexer.getAllTokens().map(token => token.text);
+        let allTokens = this._tokenStream.getTokens();
+        if(allTokens[allTokens.length - 1].text === '<EOF>') {
+            allTokens = allTokens.slice(0, -1)
+        }
+        return allTokens
     };
 
     /**
      * Get Parser instance by input string
-     * @param input
+     * @param input string
      */
-    public createParser(input: string): IParser {
+    public createParser(input: string): P {
-        const lexer = this.createLexer(input);
+        this._parserTree = null;
-        const parser: any = this.createParserFromLexer(lexer);
+        this._charStreams = CharStreams.fromString(input.toUpperCase());
-        parser.buildParseTrees = true;
+        this._lexer = this.createLexerFormCharStream(this._charStreams);
-        this._parser = parser;
 
-        return parser;
+        this._tokenStream = new CommonTokenStream(this._lexer);
+        this._tokenStream.fill();
+        
+        this._parser = this.createParserFromTokenStream(this._tokenStream);
+        this._parser.buildParseTree = true;
+
+        return this._parser
     }
 
     /**
@@ -88,18 +166,15 @@ export default abstract class BasicParser {
      * @param string input
      */
     public parserTreeToString(input: string): string {
-        const parser = this.createParser(input);
+        this.parse(input);
-        this._parser = parser;
+        return this._parserTree.toStringTree(this._parser.ruleNames);
-
-        const tree = parser.program();
-        return tree.toStringTree(parser.ruleNames);
     }
 
     /**
      * Get List-like style tree string
-     * @param parserTree
+     * @param parserTree ProgramRuleContext
      */
-    public toString(parserTree: any): string {
+    public toString(parserTree: PRC): string {
         return parserTree.toStringTree(this._parser.ruleNames);
     }
 
@@ -107,7 +182,130 @@ export default abstract class BasicParser {
      * @param listener Listener instance extends ParserListener
      * @param parserTree parser Tree
      */
-    public listen(listener: any, parserTree: any) {
+    public listen<PTL extends ParseTreeListener = ParseTreeListener>(listener: PTL, parserTree: PRC) {
         ParseTreeWalker.DEFAULT.walk(listener, parserTree);
     }
+
+    /**
+     * split input into statements
+     * @param input source string
+     */
+    public splitSQL(input): TextSlice[] {
+        this.parse(input);
+        const splitListener = this.splitListener;
+        this.listen(splitListener, this._parserTree);
+        
+        const res = splitListener.statementsContext.map(context => {
+            const { start, stop } = context;
+            return {
+                startIndex: start.startIndex,
+                endIndex: stop.stopIndex,
+                startLine: start.line,
+                endLine: stop.line,
+                startColumn: start.charPositionInLine + 1,
+                endColumn: stop.charPositionInLine + stop.text.length,
+                text: this._parsedInput.slice(start.startIndex, stop.stopIndex + 1),
+            }
+        })
+
+        return res;
+    }
+
+    /**
+     * Get suggestions of syntax and token at caretPosition
+     * @param input source string
+     * @param caretPosition caret position, such as cursor position
+     * @returns suggestion
+     */
+    public getSuggestionAtCaretPosition(input: string, caretPosition: CaretPosition): Suggestions | null {
+        const splitListener = this.splitListener;
+        // TODO: add splitListener to all sqlParser implements add remove following if
+        if(!splitListener) return null;
+
+        this.parse(input);
+        let sqlParserIns = this._parser;
+        let allTokens = this.getAllTokens(input);
+        let caretTokenIndex = findCaretTokenIndex(caretPosition, allTokens);
+        let c3Context: ParserRuleContext = this._parserTree;
+        let tokenIndexOffset: number = 0;
+
+        if(!caretTokenIndex && caretTokenIndex !== 0) return null;
+        
+        /**
+         * Split sql by statement.
+         * Try to collect candidates from the caret statement only.
+         */
+        this.listen(splitListener, this._parserTree);
+
+        // If there are multiple statements.
+        if (splitListener.statementsContext.length) {
+            // find statement rule context where caretPosition is located.
+            const caretStatementContext = splitListener?.statementsContext.find(ctx => {
+                return caretTokenIndex <= ctx.stop?.tokenIndex && caretTokenIndex >= ctx.start.tokenIndex;
+            });
+
+            if(caretStatementContext) {
+                c3Context = caretStatementContext
+            } else {
+                const lastIndex = splitListener.statementsContext.length > 1
+                    ? 2
+                    : 1;
+                const lastStatementToken= splitListener
+                    .statementsContext[splitListener?.statementsContext.length - lastIndex]
+                    .stop;
+                /**
+                 * If caretStatementContext is not found and it follows all statements.
+                 * Reparses part of the input following the penultimate statement.
+                 * And c3 will collect candidates in the new parserTreeContext.
+                 */
+                if (caretTokenIndex > lastStatementToken?.tokenIndex) {
+                    /**
+                     * Save offset of the tokenIndex in the partInput
+                     * compared to the tokenIndex in the whole input 
+                     */  
+                    tokenIndexOffset = lastStatementToken?.tokenIndex + 1;
+                    // Correct caretTokenIndex
+                    caretTokenIndex = caretTokenIndex - tokenIndexOffset;
+
+                    const inputSlice = input.slice(lastStatementToken.stopIndex + 1);
+                    const charStreams = CharStreams.fromString(inputSlice.toUpperCase());
+                    const lexer = this.createLexerFormCharStream(charStreams);
+                    const tokenStream = new CommonTokenStream(lexer);
+                    tokenStream.fill();
+                    const parser = this.createParserFromTokenStream(tokenStream);
+                    parser.buildParseTree = true;
+                    sqlParserIns = parser;
+                    c3Context = parser.program();
+                }
+            }
+        }
+
+        const core = new CodeCompletionCore(sqlParserIns);
+        core.preferredRules = this.preferredRules;
+
+        const candidates = core.collectCandidates(caretTokenIndex, c3Context);
+        const originalSuggestions = this.processCandidates(candidates, allTokens, caretTokenIndex, tokenIndexOffset);
+
+        const syntaxSuggestions: SyntaxSuggestion<WordRange>[] = originalSuggestions.syntax
+            .map(syntaxCtx => {
+                const wordRanges: WordRange[] = syntaxCtx.wordRanges.map(token => {
+                    return {
+                        text: this._parsedInput.slice(token.startIndex, token.stopIndex + 1),
+                        startIndex: token.startIndex,
+                        stopIndex: token.stopIndex,
+                        line: token.line,
+                        startColumn: token.charPositionInLine + 1,
+                        stopColumn: token.charPositionInLine + token.text.length
+                    }
+                })
+                return {
+                    syntaxContextType: syntaxCtx.syntaxContextType,
+                    wordRanges,
+                }
+            })
+        return {
+            syntax: syntaxSuggestions,
+            keywords: originalSuggestions.keywords
+        }
+    }
 }

src/parser/common/parserErrorListener.ts

@@ -1,4 +1,6 @@
 import { Token, Recognizer, ParserErrorListener, RecognitionException } from 'antlr4ts';
+import { ATNSimulator } from 'antlr4ts/atn/ATNSimulator'
+
 export interface ParserError {
     startLine: number;
     endLine: number;
@@ -8,56 +10,70 @@ export interface ParserError {
 }
 
 export interface SyntaxError<T> {
-    recognizer: Recognizer<T, any>;
+    recognizer: Recognizer<T, ATNSimulator>;
     offendingSymbol: Token;
     line: number;
     charPositionInLine: number;
     msg: string;
-    e: any;
+    e: RecognitionException;
 }
 
-type ErrorOffendingSymbol = {
-    text: string;
-};
-
 export type ErrorHandler<T> = (err: ParserError, errOption: SyntaxError<T>) => void;
 
 export class ParserErrorCollector implements ParserErrorListener {
-    private _errors: ParserError[];
+    private _parseErrors: ParserError[] = [];
-
+    private _syntaxErrors: SyntaxError<Token>[] = [];
-    constructor(error: ParserError[]) {
-        this._errors = error;
-    }
 
     syntaxError(
-        recognizer: Recognizer<ErrorOffendingSymbol, any>, offendingSymbol: ErrorOffendingSymbol, line: number,
+        recognizer: Recognizer<Token, ATNSimulator>,
-        charPositionInLine: number, msg: string, e: RecognitionException,
+        offendingSymbol: Token, 
+        line: number,
+        charPositionInLine: number, 
+        msg: string, 
+        e: RecognitionException,
     ) {
         let endCol = charPositionInLine + 1;
         if (offendingSymbol && offendingSymbol.text !== null) {
             endCol = charPositionInLine + offendingSymbol.text.length;
         }
-        this._errors.push({
+        this._parseErrors.push({
             startLine: line,
             endLine: line,
             startCol: charPositionInLine,
             endCol: endCol,
             message: msg,
         });
+
+        this._syntaxErrors.push({
+            e,
+            line,
+            msg,
+            recognizer,
+            offendingSymbol,
+            charPositionInLine,
+        })
+    }
+
+    clear() {
+        this._parseErrors = [];
+        this._syntaxErrors = [];
+    }
+
+    get parserErrors () {
+        return this._parseErrors
     }
 }
 
-
 export default class CustomParserErrorListener implements ParserErrorListener  {
     private _errorHandler;
 
-    constructor(errorListener: ErrorHandler<ErrorOffendingSymbol>) {
+    constructor(errorListener: ErrorHandler<Token>) {
         this._errorHandler = errorListener;
     }
 
     syntaxError(
-        recognizer: Recognizer<ErrorOffendingSymbol, any>, offendingSymbol: ErrorOffendingSymbol, line: number,
+        recognizer: Recognizer<Token, ATNSimulator>, offendingSymbol: Token, line: number,
-        charPositionInLine: number, msg: string, e: any,
+        charPositionInLine: number, msg: string, e: RecognitionException,
     ) {
         let endCol = charPositionInLine + 1;
         if (offendingSymbol && offendingSymbol.text !== null) {
@@ -81,4 +97,3 @@ export default class CustomParserErrorListener implements ParserErrorListener  {
         }
     }
 }
-

src/parser/flinksql.ts

@@ -1,17 +1,115 @@
-import { CharStreams, CommonTokenStream } from 'antlr4ts';
+import { Token } from 'antlr4ts';
+import { CandidatesCollection } from 'antlr4-c3';
 import { FlinkSqlLexer } from '../lib/flinksql/FlinkSqlLexer';
-import { FlinkSqlParser } from '../lib/flinksql/FlinkSqlParser';
+import {
+    FlinkSqlParser,
+    ProgramContext,
+    SqlStatementContext,
+    SqlStatementsContext
+} from '../lib/flinksql/FlinkSqlParser';
+import { FlinkSqlParserListener } from 'src/lib/flinksql/FlinkSqlParserListener';
+import { SyntaxContextType, Suggestions, SyntaxSuggestion } from './common/basic-parser-types';
 import BasicParser from './common/basicParser';
-export default class FlinkSQL extends BasicParser {
+
-    public createLexer(input: string): FlinkSqlLexer {
+export default class FlinkSQL extends BasicParser<FlinkSqlLexer, ProgramContext, FlinkSqlParser> {
-        const chars = CharStreams.fromString(input.toUpperCase()); // Some Lexer only support uppercase token, So you need transform
+    public createLexerFormCharStream(charStreams) {
-        const lexer = new FlinkSqlLexer(chars);
+        const lexer = new FlinkSqlLexer(charStreams);
         return lexer;
     }
-    public createParserFromLexer(lexer: FlinkSqlLexer): FlinkSqlParser {
+
-        const tokens = new CommonTokenStream(lexer);
+    public createParserFromTokenStream(tokenStream) {
-        const parser = new FlinkSqlParser(tokens);
+        const parser = new FlinkSqlParser(tokenStream);
         return parser;
     }
+
+    public preferredRules = new Set([
+        FlinkSqlParser.RULE_tablePath, // table name >> select / insert ...
+        FlinkSqlParser.RULE_tablePathCreate, // table name >> create 
+        FlinkSqlParser.RULE_databasePath, // database name >> show
+        FlinkSqlParser.RULE_databasePathCreate, // database name >> create 
+        FlinkSqlParser.RULE_catalogPath, // catalog name
+    ]);
+
+    protected get splitListener () {
+        return new FlinkSqlSplitListener();
+    }
+
+    public processCandidates(
+        candidates: CandidatesCollection,
+        allTokens: Token[],
+        caretTokenIndex: number,
+        tokenIndexOffset: number
+    ): Suggestions<Token> {
+        const originalSyntaxSuggestions: SyntaxSuggestion<Token>[] = [];
+        const keywords: string[] = [];
+
+        for (let candidate of candidates.rules) {
+            const [ruleType, candidateRule] = candidate;
+            const startTokenIndex = candidateRule.startTokenIndex + tokenIndexOffset;
+            const tokenRanges = allTokens.slice(startTokenIndex, caretTokenIndex + 1);
+
+            let syntaxContextType: SyntaxContextType;
+            switch (ruleType) {
+                case FlinkSqlParser.RULE_tablePath: {
+                    syntaxContextType = SyntaxContextType.TABLE;
+                    break;
+                }
+                case FlinkSqlParser.RULE_tablePathCreate: {
+                    syntaxContextType = SyntaxContextType.TABLE_CREATE;
+                    break;
+                }
+                case FlinkSqlParser.RULE_databasePath: {
+                    syntaxContextType = SyntaxContextType.DATABASE;
+                    break;
+                }
+                case FlinkSqlParser.RULE_databasePathCreate: {
+                    syntaxContextType = SyntaxContextType.DATABASE;
+                    break;
+                }
+                case FlinkSqlParser.RULE_catalogPath: {
+                    syntaxContextType = SyntaxContextType.CATALOG;
+                    break;
+                }
+                default:
+                    break;
+            }
+
+            if (syntaxContextType) {
+                originalSyntaxSuggestions.push({
+                    syntaxContextType,
+                    wordRanges: tokenRanges
+                })
+            }
+        }
+
+        for (let candidate of candidates.tokens) {
+            const symbolicName = this._parser.vocabulary.getSymbolicName(candidate[0]);
+            const displayName = this._parser.vocabulary.getDisplayName(candidate[0]);
+            if(symbolicName && symbolicName.startsWith('KW_')) {
+                const keyword = displayName.startsWith("'") && displayName.endsWith("'")
+                    ? displayName.slice(1, -1)
+                    : displayName
+                keywords.push(keyword);
+            }
+        }
+        return {
+            syntax: originalSyntaxSuggestions,
+            keywords,
+        }
+    }
 }
 
+export class FlinkSqlSplitListener implements FlinkSqlParserListener {
+    private _statementsContext: SqlStatementContext[] = [];
+
+    exitSqlStatement = (ctx: SqlStatementContext) => {
+        this._statementsContext.push(ctx);
+    }
+
+    enterSqlStatements = (ctx: SqlStatementsContext) => {
+    };
+    
+    get statementsContext () {
+        return this._statementsContext;
+    }
+}

src/parser/generic.ts

@@ -1,17 +1,35 @@
-import { CharStreams, CommonTokenStream } from 'antlr4ts';
+import { Token } from 'antlr4ts';
+import { CandidatesCollection } from 'antlr4-c3';
 import { SqlLexer } from '../lib/generic/SqlLexer';
-import { SqlParser } from '../lib/generic/SqlParser';
+import { SqlParser, ProgramContext } from '../lib/generic/SqlParser';
 import BasicParser from './common/basicParser';
+import { Suggestions } from './common/basic-parser-types';
 
-export default class GenericSQL extends BasicParser {
+export default class GenericSQL extends BasicParser<SqlLexer, ProgramContext, SqlParser> {
-    public createLexer(input: string): SqlLexer {
+    public createLexerFormCharStream(charStreams): SqlLexer {
-        const chars = CharStreams.fromString(input.toUpperCase()); // Some Lexer only support uppercase token, So you need transform
+        const lexer = new SqlLexer(charStreams);
-        const lexer = new SqlLexer(chars);
         return lexer;
     }
-    public createParserFromLexer(lexer: SqlLexer): SqlParser {
+
-        const tokenStream = new CommonTokenStream(lexer);
+    public createParserFromTokenStream(tokenStream): SqlParser {
         return new SqlParser(tokenStream);
     }
+
+    public preferredRules: Set<number> = new Set();
+
+    protected get splitListener () {
+        return null as any;
+    }
+
+    public processCandidates(
+        candidates: CandidatesCollection, 
+        allTokens: Token[], 
+        caretTokenIndex: number
+    ): Suggestions<Token> {
+        return {
+            syntax: [],
+            keywords: []
+        }
+    }
 }
 

src/parser/hive.ts

@@ -1,17 +1,36 @@
-import { CharStreams, CommonTokenStream } from 'antlr4ts';
+import { Token } from 'antlr4ts';
+import { CandidatesCollection } from 'antlr4-c3';
 import { HiveSqlLexer } from '../lib/hive/HiveSqlLexer';
-import { HiveSql } from '../lib/hive/HiveSql';
+import { HiveSql, ProgramContext } from '../lib/hive/HiveSql';
 import BasicParser from './common/basicParser';
+import { Suggestions } from './common/basic-parser-types';
 
-export default class HiveSQL extends BasicParser {
+
-    public createLexer(input: string): HiveSqlLexer {
+export default class HiveSQL extends BasicParser<HiveSqlLexer, ProgramContext, HiveSql> {
-        const chars = CharStreams.fromString(input.toUpperCase());
+    public createLexerFormCharStream(charStreams) {
-        const lexer = new HiveSqlLexer(chars);
+        const lexer = new HiveSqlLexer(charStreams);
         return lexer;
     }
-    public createParserFromLexer(lexer: HiveSqlLexer): HiveSql {
+
-        const tokenStream = new CommonTokenStream(lexer);
+    public createParserFromTokenStream(tokenStream) {
         return new HiveSql(tokenStream);
     }
+
+    protected get splitListener () {
+        return null as any;
+    }
+
+    public preferredRules: Set<number> = new Set();
+
+    public processCandidates(
+        candidates: CandidatesCollection, 
+        allTokens: Token[], 
+        caretTokenIndex: number
+    ): Suggestions<Token> {
+        return {
+            syntax: [],
+            keywords: []
+        }
+    }
 }
 

src/parser/pgsql.ts

@@ -1,17 +1,34 @@
-import { CharStreams, CommonTokenStream, Lexer } from 'antlr4ts';
+import { Token } from 'antlr4ts';
-
+import { CandidatesCollection } from 'antlr4-c3';
-import BasicParser from './common/basicParser';
 import { PostgreSQLLexer } from '../lib/pgsql/PostgreSQLLexer';
-import { PostgreSQLParser } from '../lib/pgsql/PostgreSQLParser';
+import { PostgreSQLParser, ProgramContext } from '../lib/pgsql/PostgreSQLParser';
+import BasicParser from './common/basicParser';
+import { Suggestions } from './common/basic-parser-types';
 
-export default class PostgresSQL extends BasicParser {
+export default class PostgresSQL extends BasicParser<PostgreSQLLexer, ProgramContext, PostgreSQLParser> {
-    public createLexer(input: string): PostgreSQLLexer {
+    public createLexerFormCharStream(charStreams) {
-        const chars = CharStreams.fromString(input.toUpperCase());
+        const lexer = new PostgreSQLLexer(charStreams);
-        const lexer = new PostgreSQLLexer(chars);
         return lexer;
     }
-    public createParserFromLexer(lexer: Lexer): PostgreSQLParser {
+
-        const tokenStream = new CommonTokenStream(lexer);
+    public createParserFromTokenStream(tokenStream) {
         return new PostgreSQLParser(tokenStream);
     }
+
+    public preferredRules: Set<number> = new Set();
+
+    protected get splitListener () {
+        return null as any;
+    }
+
+    public processCandidates(
+        candidates: CandidatesCollection, 
+        allTokens: Token[], 
+        caretTokenIndex: number
+    ): Suggestions<Token> {
+        return {
+            syntax: [],
+            keywords: []
+        }
+    }
 }

src/parser/plsql.ts

@@ -1,17 +1,34 @@
-import { CharStreams, CommonTokenStream, Lexer } from 'antlr4ts';
+import { Token } from 'antlr4ts';
-
+import { CandidatesCollection } from 'antlr4-c3';
-import BasicParser from './common/basicParser';
 import { PlSqlLexer } from '../lib/plsql/PlSqlLexer';
-import { PlSqlParser } from '../lib/plsql/PlSqlParser';
+import { PlSqlParser, ProgramContext } from '../lib/plsql/PlSqlParser';
+import BasicParser from './common/basicParser';
+import { Suggestions } from './common/basic-parser-types';
 
-export default class PLSQLParser extends BasicParser {
+export default class PLSQL extends BasicParser<PlSqlLexer, ProgramContext, PlSqlParser> {
-    public createLexer(input: string): PlSqlLexer {
+    public createLexerFormCharStream(charStreams) {
-        const chars = CharStreams.fromString(input.toUpperCase());
+        const lexer = new PlSqlLexer(charStreams);
-        const lexer = new PlSqlLexer(chars);
         return lexer;
     }
-    public createParserFromLexer(lexer: Lexer): PlSqlParser {
+
-        const tokenStream = new CommonTokenStream(lexer);
+    public createParserFromTokenStream(tokenStream) {
         return new PlSqlParser(tokenStream);
     }
+
+    public preferredRules: Set<number> = new Set();
+
+    protected get splitListener () {
+        return null as any;
+    }
+
+    public processCandidates(
+        candidates: CandidatesCollection, 
+        allTokens: Token[], 
+        caretTokenIndex: number
+    ): Suggestions<Token> {
+        return {
+            syntax: [],
+            keywords: []
+        }
+    }
 }

src/parser/spark.ts

@@ -1,16 +1,34 @@
-import { CharStreams, CommonTokenStream } from 'antlr4ts';
+import { Token } from 'antlr4ts';
-import BasicParser from './common/basicParser';
+import { CandidatesCollection } from 'antlr4-c3';
 import { SparkSqlLexer } from '../lib/spark/SparkSqlLexer';
-import { SparkSqlParser } from '../lib/spark/SparkSqlParser';
+import { SparkSqlParser, ProgramContext } from '../lib/spark/SparkSqlParser';
+import BasicParser from './common/basicParser';
+import { Suggestions } from './common/basic-parser-types';
 
-export default class SparkSQL extends BasicParser {
+export default class SparkSQL extends BasicParser<SparkSqlLexer, ProgramContext, SparkSqlParser> {
-    public createLexer(input: string): SparkSqlLexer {
+    public createLexerFormCharStream(charStreams) {
-        const chars = CharStreams.fromString(input.toUpperCase()); // Some Lexer only support uppercase token, So you need transform
+        const lexer = new SparkSqlLexer(charStreams);
-        const lexer = new SparkSqlLexer(chars);
         return lexer;
     }
-    public createParserFromLexer(lexer: SparkSqlLexer): SparkSqlParser {
+
-        const tokenStream = new CommonTokenStream(lexer);
+    public createParserFromTokenStream(tokenStream) {
         return new SparkSqlParser(tokenStream);
     }
+
+    public preferredRules: Set<number> = new Set();
+
+    protected get splitListener () {
+        return null as any;
+    }
+
+    public processCandidates(
+        candidates: CandidatesCollection, 
+        allTokens: Token[], 
+        caretTokenIndex: number
+    ): Suggestions<Token> {
+        return {
+            syntax: [],
+            keywords: []
+        }
+    }
 }

src/parser/trinosql.ts

@@ -1,17 +1,36 @@
-import { CharStreams, CommonTokenStream, Lexer } from 'antlr4ts';
+import { Token } from 'antlr4ts';
+import { CandidatesCollection } from 'antlr4-c3';
 import { TrinoSqlLexer } from '../lib/trinosql/TrinoSqlLexer';
-import { TrinoSqlParser } from '../lib/trinosql/TrinoSqlParser';
+import { TrinoSqlParser, ProgramContext } from '../lib/trinosql/TrinoSqlParser';
 import BasicParser from './common/basicParser';
-export default class trinoSQL extends BasicParser {
+import { Suggestions } from './common/basic-parser-types';
-    public createLexer(input: string): TrinoSqlLexer {
+
-        const chars = CharStreams.fromString(input.toUpperCase()); // Some Lexer only support uppercase token, So you need transform
+export default class TrinoSQL extends BasicParser<TrinoSqlLexer, ProgramContext, TrinoSqlParser> {
-        const lexer = new TrinoSqlLexer(chars);
+    public createLexerFormCharStream(charStreams) {
+        const lexer = new TrinoSqlLexer(charStreams);
         return lexer;
     }
-    public createParserFromLexer(lexer: Lexer): TrinoSqlParser {
+
-        const tokens = new CommonTokenStream(lexer);
+    public createParserFromTokenStream(tokenStream) {
-        const parser = new TrinoSqlParser(tokens);
+        const parser = new TrinoSqlParser(tokenStream);
         return parser;
     }
+
+    protected get splitListener () {
+        return null as any;
+    }
+
+    public preferredRules: Set<number> = new Set();
+
+    public processCandidates(
+        candidates: CandidatesCollection, 
+        allTokens: Token[], 
+        caretTokenIndex: number
+    ): Suggestions<Token> {
+        return {
+            syntax: [],
+            keywords: []
+        }
+    }
 }
 

src/utils/findCaretTokenIndex.ts

@@ -0,0 +1,33 @@
+import { Token } from "antlr4ts";
+import { CaretPosition } from "../../src/parser/common/basic-parser-types";
+
+/**
+ * find token index via caret position (cursor position)
+ * @param caretPosition 
+ * @param allTokens all the tokens
+ * @returns caretTokenIndex
+ */
+export function findCaretTokenIndex(caretPosition: CaretPosition, allTokens: Token[]) {
+    const { lineNumber: caretLine, column: caretCol } = caretPosition;
+    let left = 0;
+    let right = allTokens.length - 1;
+
+    while(left <= right) {
+        const mid = left + ((right - left) >> 1);
+        const token = allTokens[mid];
+        if (token.line > caretLine || (
+            token.line === caretLine
+            && token.charPositionInLine + 1 >= caretCol
+        )) {
+            right = mid - 1;
+        } else if (token.line < caretLine || (
+            token.line === caretLine
+            && token.charPositionInLine + token.text.length + 1 < caretCol
+        )) {
+            left = mid + 1;
+        } else {
+            return allTokens[mid].tokenIndex
+        }
+    }
+    return null;
+}

test/parser/flinksql/suggestion/fixtures/syntaxSuggestion.sql

@@ -0,0 +1,11 @@
+INSERT INTO cat.db.tb
+
+SELECT * FROM cat.db
+
+CREATE TABLE cat.db ;
+
+SHOW TABLES FROM cat
+
+ALTER DATABASE cat.
+
+USE DATABASE cat.

test/parser/flinksql/suggestion/fixtures/tokenSuggestion.sql

@@ -0,0 +1,7 @@
+SELECT * FROM aa.bb;
+
+USE 
+;
+CREATE 
+;
+SHOW 

test/parser/flinksql/suggestion/syntaxSuggestion.test.ts

@@ -0,0 +1,90 @@
+import fs from 'fs';
+import path from 'path';
+import { CaretPosition, SyntaxContextType } from '../../../../src/parser/common/basic-parser-types';
+import FlinkSQL from '../../../../src/parser/flinksql'
+
+const syntaxSql = fs.readFileSync(path.join(__dirname, 'fixtures', 'syntaxSuggestion.sql'), 'utf-8');
+
+describe('Flink SQL Syntax Suggestion', () => {
+    const parser = new FlinkSQL();
+
+    test('Validate Syntax SQL', () => {
+        expect(parser.validate(syntaxSql).length).not.toBe(0);
+        expect(parser.validate(syntaxSql).length).not.toBe(0);
+        expect(parser.validate(syntaxSql).length).not.toBe(0);
+    })
+
+    test('Insert table ', () => {
+        const pos: CaretPosition = {
+            lineNumber: 1,
+            column: 22
+        }
+        const suggestion = parser.getSuggestionAtCaretPosition(syntaxSql, pos)?.syntax?.[0];
+        
+        expect(suggestion?.syntaxContextType === SyntaxContextType.TABLE)
+        
+        expect(suggestion?.wordRanges.map(token => token.text))
+            .toEqual([ 'cat', '.', 'db', '.', 'tb' ])
+    })
+
+    test('Select table', () => {
+        const pos: CaretPosition = {
+            lineNumber: 3,
+            column: 21
+        }
+        const suggestion = parser.getSuggestionAtCaretPosition(syntaxSql, pos)?.syntax?.[0];
+        
+        expect(suggestion?.syntaxContextType === SyntaxContextType.TABLE)
+        expect(suggestion?.wordRanges.map(token => token.text))
+            .toEqual([ 'cat', '.', 'db' ])
+    })
+
+    test('Create table', () => {
+        const pos: CaretPosition = {
+            lineNumber: 5,
+            column: 20
+        }
+        const suggestion = parser.getSuggestionAtCaretPosition(syntaxSql, pos)?.syntax?.[0];
+        
+        expect(suggestion?.syntaxContextType === SyntaxContextType.TABLE_CREATE)
+        expect(suggestion?.wordRanges.map(token => token.text))
+            .toEqual([ 'cat', '.', 'db' ])
+    })
+
+    test('Show tables from', () => {
+        const pos: CaretPosition = {
+            lineNumber: 7,
+            column: 21
+        }
+        const suggestion = parser.getSuggestionAtCaretPosition(syntaxSql, pos)?.syntax?.[0];
+        
+        expect(suggestion?.syntaxContextType === SyntaxContextType.TABLE)
+        expect(suggestion?.wordRanges.map(token => token.text))
+            .toEqual([ 'cat' ])
+    })
+
+    test('Alter database', () => {
+        const pos: CaretPosition = {
+            lineNumber: 9,
+            column: 20
+        }
+        const suggestion = parser.getSuggestionAtCaretPosition(syntaxSql, pos)?.syntax?.[0];
+        
+        expect(suggestion?.syntaxContextType === SyntaxContextType.DATABASE)
+        expect(suggestion?.wordRanges.map(token => token.text))
+            .toEqual([ 'cat', '.' ])
+    })
+
+    test('Use database', () => {
+        const pos: CaretPosition = {
+            lineNumber: 9,
+            column: 20
+        }
+        const suggestion = parser.getSuggestionAtCaretPosition(syntaxSql, pos)?.syntax?.[0];
+        
+        expect(suggestion?.syntaxContextType === SyntaxContextType.DATABASE)
+        expect(suggestion?.wordRanges.map(token => token.text))
+            .toEqual([ 'cat', '.' ])
+    })
+
+})

test/parser/flinksql/suggestion/tokenSuggestion.test.ts

@@ -0,0 +1,57 @@
+import fs from 'fs';
+import path from 'path';
+import { CaretPosition } from '../../../../src/parser/common/basic-parser-types';
+import FlinkSQL from '../../../../src/parser/flinksql'
+
+const tokenSql = fs.readFileSync(path.join(__dirname, 'fixtures', 'tokenSuggestion.sql'), 'utf-8');
+
+describe('Flink SQL Syntax Suggestion', () => {
+    const parser = new FlinkSQL();
+
+    test('Use Statement ', () => {
+        const pos: CaretPosition = {
+            lineNumber: 3,
+            column: 5
+        }
+        const suggestion = parser.getSuggestionAtCaretPosition(tokenSql, pos)?.keywords;
+   
+        expect(suggestion)
+            .toEqual([ 'MODULES', 'CATALOG' ])
+    })
+
+    test('Create Statement ', () => {
+        const pos: CaretPosition = {
+            lineNumber: 5,
+            column: 8
+        }
+        const suggestion = parser.getSuggestionAtCaretPosition(tokenSql, pos)?.keywords;
+   
+        expect(suggestion)
+            .toEqual([ 'CATALOG', 'FUNCTION', 'TEMPORARY', 'VIEW', 'DATABASE', 'TABLE' ])
+    })
+
+    test('Show Statement ', () => {
+        const pos: CaretPosition = {
+            lineNumber: 7,
+            column: 6
+        }
+        const suggestion = parser.getSuggestionAtCaretPosition(tokenSql, pos)?.keywords;
+   
+        expect(suggestion)
+            .toEqual([
+                'MODULES',
+                'FULL',
+                'FUNCTIONS',
+                'USER',
+                'CREATE',
+                'COLUMNS',
+                'TABLES',
+                'CURRENT',
+                'CATALOGS',
+                'DATABASES',
+                'JARS',
+                'VIEWS'
+            ])
+    })
+
+})

yarn.lock

@@ -961,14 +961,21 @@ ansi-styles@^5.0.0:
   resolved "https://registry.yarnpkg.com/ansi-styles/-/ansi-styles-5.2.0.tgz#07449690ad45777d1924ac2abb2fc8895dba836b"
   integrity sha512-Cxwpt2SfTzTtXcfOlzGEee8O+c+MmUgGrNiBcXnuWxuFJHe6a5Hz7qwhwe5OgaSYI0IJvkLqWX1ASG+cJOkEiA==
 
+antlr4-c3@^3.0.1:
+  version "3.0.1"
+  resolved "https://registry.npmmirror.com/antlr4-c3/-/antlr4-c3-3.0.1.tgz#e9b6ba7b796e7afc35630ffa6fac4d915f152c99"
+  integrity sha512-Vbizas0WK4Id6l1f48ANYHFZgfzmj82LZx4OuB/a87vCpyoUwofrlJ+sCiL1qT/D2SWf8HEcBPCsgskdx8NnzQ==
+  dependencies:
+    antlr4ts "0.5.0-alpha.4"
+
 antlr4ts-cli@^0.5.0-alpha.4:
   version "0.5.0-alpha.4"
   resolved "https://registry.yarnpkg.com/antlr4ts-cli/-/antlr4ts-cli-0.5.0-alpha.4.tgz#f3bfc37f10131e78d7b981c397a2aaa0450b67f6"
   integrity sha512-lVPVBTA2CVHRYILSKilL6Jd4hAumhSZZWA7UbQNQrmaSSj7dPmmYaN4bOmZG79cOy0lS00i4LY68JZZjZMWVrw==
 
-antlr4ts@^0.5.0-alpha.4:
+antlr4ts@0.5.0-alpha.4, antlr4ts@^0.5.0-alpha.4:
   version "0.5.0-alpha.4"
-  resolved "https://registry.yarnpkg.com/antlr4ts/-/antlr4ts-0.5.0-alpha.4.tgz#71702865a87478ed0b40c0709f422cf14d51652a"
+  resolved "https://registry.npmmirror.com/antlr4ts/-/antlr4ts-0.5.0-alpha.4.tgz#71702865a87478ed0b40c0709f422cf14d51652a"
   integrity sha512-WPQDt1B74OfPv/IMS2ekXAKkTZIHl88uMetg6q3OTqgFxZ/dxDXI0EWLyZid/1Pe6hTftyg5N7gel5wNAGxXyQ==
 
 anymatch@^3.0.3: