add lint rule always using AS to rename columns (#44)

Author: joe-re

packages/server/src/complete.ts

@@ -130,7 +130,7 @@ function createTablesFromFromNodes(fromNodes: FromTableNode[]): Schema {
     }
     const columns = c.subquery.columns.map(v => {
       if (typeof v === 'string') { return null }
-      return { columnName: v.as || v.expr.column || '', description: 'alias' }
+      return { columnName: v.as || (v.expr.type === 'column_ref' && v.expr.column) || '', description: 'alias' }
     })
     return p.concat({ database: null, columns, tableName: c.as })
   }, [])
@@ -200,7 +200,7 @@ function completeSelectStatement(ast: SelectStatement, _pos: Pos, _schema: Schem
     const rest = ast.columns.slice(1, ast.columns.length)
     const lastColumn = rest.reduce((p, c) => p.location.end.offset < c.location.end.offset ? c : p ,first)
     if (
-      FROM_KEYWORD.label.startsWith(lastColumn.expr.column) ||
+      (lastColumn.expr.type === 'column_ref' && FROM_KEYWORD.label.startsWith(lastColumn.expr.column)) ||
       (lastColumn.as && FROM_KEYWORD.label.startsWith(lastColumn.as))
      ) {
       candidates.push(FROM_KEYWORD)

packages/sql-parser/base/fromClauseParser.js

@@ -116,7 +116,7 @@ export type ValuesClause = {
 
 export type ColumnListItemNode = {
   type: 'column_list_item',
-  expr: ColumnRefNode,
+  expr: ColumnRefNode | AggrFuncNode,
   as: string | null,
   location: NodeRange
 }
@@ -128,6 +128,15 @@ export type ColumnRefNode = {
   location: NodeRange
 }
 
+export type AggrFuncNode = {
+  type: 'aggr_func'
+  name: string
+  args: {
+    expr: ColumnRefNode
+  },
+  location: NodeRange
+}
+
 export type StarNode = { type: 'star', value: '*' }
 
 export type FromTableNode = TableNode | SubqueryNode | IncompleteSubqueryNode

packages/sql-parser/base/parser.js

@@ -831,7 +831,8 @@ aggr_fun_smma
         name : name,
         args : {
           expr : e  
-        } 
+        },
+        location: location()
       }   
     }
 
@@ -843,7 +844,8 @@ aggr_fun_count
       return {
         type : 'aggr_func',
         name : name,
-        args : arg 
+        args : arg,
+        location: location()
       }   
     }
 

packages/sql-parser/index.d.ts

@@ -72,7 +72,8 @@ $ sqlint --fix .
     "linebreak-after-clause-keyword": "error",
     "reserved-word-case": ["error", "upper"],
     "space-surrounding-operators": "error",
-    "where-clause-new-line": "error"
+    "where-clause-new-line": "error",
+    "align-where-clause-to-the-first": "error",
   }
 }
 ```
@@ -270,4 +271,47 @@ foo.c = 'c' AND
 foo.d = 'd'
 ```
 
+##### align-where-clause-to-the-first
+
+Where clauses must align to the first clause.
 
+Good
+```sql
+SELECT foo.a
+FROM foo 
+WHERE foo.a = 'a' AND foo.b = 'b' AND
+      foo.c = 'c' AND
+      foo.d = 'd'
+```
+
+Bad
+```sql
+SELECT foo.a
+FROM foo 
+WHERE foo.a = 'a' AND foo.b = 'b' AND
+foo.c = 'c' AND
+foo.d = 'd'
+```
+##### require-as-to-rename-column
+
+As is always required to rename a column name.
+
+Good
+```sql
+SELECT
+  employees.name AS employee_name,
+  COUNT(tasks.id) AS assigned_task_count
+FROM
+  employees LEFT JOIN tasks
+    ON employees.id = tasks.id
+```
+
+Bad
+```sql
+SELECT
+  employees.name employee_name,
+  COUNT(tasks.id) assigned_task_count
+FROM
+  employees LEFT JOIN tasks
+    ON employees.id = tasks.id
+```

packages/sql-parser/parser.pegjs

@@ -1,4 +1,5 @@
 module.exports = {
     preset: 'ts-jest',
     testEnvironment: 'node',
+    modulePathIgnorePatterns: ['dist']
   };

packages/sqlint/README.md

@@ -19,7 +19,8 @@ const defaultConfig: Config = {
     'reserved-word-case': { level: ErrorLevel.Error, option: 'upper' },
     'space-surrounding-operators': { level: ErrorLevel.Error },
     'where-clause-new-line': { level: ErrorLevel.Error },
-    'align-where-clause-to-the-first': { level: ErrorLevel.Error }
+    'align-where-clause-to-the-first': { level: ErrorLevel.Error },
+    'require-as-to-rename-column': { level: ErrorLevel.Error }
   }
 }
 

packages/sqlint/jest.config.js

@@ -5,6 +5,7 @@ import { columnNewLine } from './columnNewLine'
 import { alignColumnToTheFirst } from './alignColumnToTheFirst'
 import { whereClauseNewLine } from './whereClauseNewLine'
 import { alignWhereClauseToTheFirst } from './alignWhereClauseToTheFirst'
+import { requireAsToRenameColumn } from './requireAsToRenameColumn'
 import { parse, NodeRange, AST, BaseNode } from '@joe-re/sql-parser'
 import { Fixer, FixDescription, createFixer } from '../fixer'
 
@@ -69,6 +70,7 @@ export function execute(sql: string, config: Config): Diagnostic[] {
   registerRule(alignColumnToTheFirst, config, sql)
   registerRule(whereClauseNewLine, config, sql)
   registerRule(alignWhereClauseToTheFirst, config, sql)
+  registerRule(requireAsToRenameColumn, config, sql)
   const ast = parse(sql)
   return walk(ast)
 }

packages/sqlint/src/cli/loadConfig.ts

@@ -0,0 +1,28 @@
+import { SelectStatement } from '@joe-re/sql-parser'
+import { Rule, RuleConfig } from './index'
+
+const META = {
+  name: 'require-as-to-rename-column',
+  type: 'select'
+}
+
+export const requireAsToRenameColumn: Rule<SelectStatement, RuleConfig> = {
+  meta: META,
+  create: (context) => {
+    if (!Array.isArray(context.node.columns)) {
+      return
+    }
+    const invalidColumns = context.node.columns.filter(v => v.as).filter(v => {
+      return !context.getAfterSQL(v.expr.location).trim().match(/^(AS|as)\s/)
+    })
+    return invalidColumns.map(v => {
+      return {
+        message: 'Require AS keyword to rename a column',
+        location: v.location,
+        fix: (fixer) => {
+          return fixer.insertText(v.expr.location.end.offset, ' AS')
+        }
+      }
+    })
+  }
+}