feat: support drop table statement (joe-re#218)

* feat: support drop table statement

* test: server should add drop as a candidate

* fix: create drop statement type and use it on server

* ref: renmae statement interface and remove db from it

---------

Co-authored-by: ravime <ravime@g.globo>

Author: ravilock

packages/server/src/complete/complete.ts

@@ -10,6 +10,7 @@ import {
   ExpectedLiteralNode,
   AST,
   AlterTableStatement,
+  DropTableStatement,
 } from '@joe-re/sql-parser'
 import log4js from 'log4js'
 import { CompletionItem } from 'vscode-languageserver-types'
@@ -282,6 +283,12 @@ class Completer {
     }
   }
 
+  addCandidatesForParsedDropStatement(ast: DropTableStatement) {
+    if (isPosInLocation(ast.table.location, this.pos)) {
+      this.addCandidatesForTables(this.schema.tables, false)
+    }
+  }
+
   addCandidatesForParsedAlterTableStatement(ast: AlterTableStatement) {
     if (ast.command.type === 'alter_table_drop_column') {
       if (isPosInLocation(ast.command.column.location, this.pos)) {
@@ -339,6 +346,8 @@ class Completer {
       this.addCandidatesForParsedSelectQuery(ast)
     } else if (ast.type === 'alter_table') {
       this.addCandidatesForParsedAlterTableStatement(ast)
+    } else if (ast.type === 'drop_table') {
+      this.addCandidatesForParsedDropStatement(ast)
     } else {
       console.log(`AST type not supported yet: ${ast.type}`)
     }

packages/server/test/complete.test.ts

@@ -126,9 +126,16 @@ describe('keyword completion', () => {
   test("complete 'DELETE' keyword", () => {
     const sql = 'D'
     const result = complete(sql, { line: 0, column: sql.length })
-    expect(result.candidates.length).toEqual(1)
+    expect(result.candidates.length).toEqual(2) // includes drop table
     expect(result.candidates[0].label).toEqual('DELETE')
   })
+
+  test("complete 'DROP TABLE' keyword", () => {
+    const sql = 'D'
+    const result = complete(sql, { line: 0, column: sql.length })
+    expect(result.candidates.length).toEqual(2) // includes delete
+    expect(result.candidates[1].label).toEqual('DROP TABLE')
+  })
 })
 
 const SIMPLE_SCHEMA = {
@@ -983,3 +990,12 @@ describe('DELETE statement', () => {
     expect(result.candidates[1].label).toEqual('COLUMN2')
   })
 })
+
+describe('DROP statement', () => {
+  test('complete table name', () => {
+    const sql = 'DROP TABLE T'
+    const result = complete(sql, { line: 0, column: sql.length }, SIMPLE_SCHEMA)
+    expect(result.candidates.length).toEqual(1)
+    expect(result.candidates[0].label).toEqual('TABLE1')
+  })
+})