feat: support $.first aggr

packages/core/src/eval.ts

@@ -138,6 +138,7 @@ export namespace Eval {
     number: Unary<any, number>
 
     // aggregation / json
+    first: Aggr<any>
     sum: Aggr<number>
     avg: Aggr<number>
     max: Aggr<Comparable>
@@ -290,6 +291,9 @@ const unwrapAggr = (expr: any, def?: Type) => {
 }
 
 // aggregation
+Eval.first = unary('first', (expr, table) => Array.isArray(table)
+  ? table.map(data => executeAggr(expr, data))[0]
+  : Array.from(executeEval(table, expr))[0], (expr) => unwrapAggr(expr))
 Eval.sum = unary('sum', (expr, table) => Array.isArray(table)
   ? table.reduce<number>((prev, curr) => prev + executeAggr(expr, curr), 0)
   : Array.from<number>(executeEval(table, expr)).reduce((prev, curr) => prev + curr, 0), Type.Number)

packages/mongo/src/builder.ts

@@ -1,5 +1,5 @@
 import { Dict, isNullable, mapValues } from 'cosmokit'
 import { Eval, Field, flatten, isAggrExpr, isComparable, isEvalExpr, isFlat, makeRegExp, Model, Query, Selection, Type, unravel } from '@cordisjs/plugin-database'
 import { Filter, FilterOperators, ObjectId } from 'mongodb'
 import MongoDriver from '.'
 
@@ -83,7 +83,7 @@
   [K in keyof Eval.Static as `$${K}`]?: (expr: ExtractUnary<Parameters<Eval.Static[K]>>, group?: object) => any
 } & { $: (expr: any, group?: object) => any }
 
-const aggrKeys = ['$sum', '$avg', '$min', '$max', '$count', '$length', '$array']
+const aggrKeys = ['$first', '$sum', '$avg', '$min', '$max', '$count', '$length', '$array']
 
 export class Builder {
   private counter = 0

packages/mysql/src/builder.ts

@@ -78,7 +78,7 @@ export class MySQLBuilder extends Builder {
     this.transformers['boolean'] = {
       encode: value => `if(${value}=true, 1, 0)`,
       decode: value => `if(${value}=1, true, false)`,
-      load: value => isNullable(value) ? value : !!value,
+      load: value => isNullable(value) ? value : !!+value,
       dump: value => isNullable(value) ? value : value ? 1 : 0,
     }
 

packages/sql-utils/src/index.ts

@@ -186,6 +186,7 @@ export class Builder {
       $literal: ([value, type]) => this.escape(value, type as any),
 
       // aggregation
+      $first: (expr) => this.parseEval(expr, false),
       $sum: (expr) => this.createAggr(expr, value => `ifnull(sum(${value}), 0)`),
       $avg: (expr) => this.createAggr(expr, value => `avg(${value})`),
       $min: (expr) => this.createAggr(expr, value => `min(${value})`),

packages/tests/src/query.ts

@@ -318,19 +318,19 @@ namespace QueryOperators {
         row => $.eq($.xor(0, row.value, 3), 7),
       )).eventually.to.have.shape([{ value: 4 }])
 
-      await expect(database.eval('temp1', _ => $.max($.not(2 ** 30)))).eventually.to.deep.equal(-(2 ** 30) - 1)
-      await expect(database.eval('temp1', _ => $.max($.not(-(2 ** 30))))).eventually.to.deep.equal(2 ** 30 - 1)
-      await expect(database.eval('temp1', _ => $.max($.or(-(2 ** 30), 1)))).eventually.to.deep.equal(-(2 ** 30) + 1)
-
-      await expect(database.eval('temp1', _ => $.max($.xor(2, 3, 6)))).eventually.to.deep.equal(7)
-      await expect(database.eval('temp1', _ => $.array($.xor(true, false)))).eventually.to.include.members([true])
-      await expect(database.eval('temp1', _ => $.array($.xor(true, false, true)))).eventually.to.include.members([false])
-
-      await expect(database.eval('temp1', _ => $.max($.not(BigInt(2 ** 40))))).eventually.to.deep.equal(BigInt(-(2 ** 40) - 1))
-      await expect(database.eval('temp1', _ => $.max($.and(9223372036854775701n, 9223372036854775702n)))).eventually.to.deep.equal(9223372036854775700n)
-      await expect(database.eval('temp1', _ => $.max($.or(9223372036854775701n, 1n)))).eventually.to.deep.equal(9223372036854775701n)
-      await expect(database.eval('temp1', _ => $.max($.xor(9223372036854775701n, 9223372036854775702n)))).eventually.to.deep.equal(3n)
-      await expect(database.eval('temp1', _ => $.max($.not(9223372036854775701n)))).eventually.to.deep.equal(-9223372036854775702n)
+      await expect(database.eval('temp1', _ => $.first($.not(2 ** 30)))).eventually.to.deep.equal(-(2 ** 30) - 1)
+      await expect(database.eval('temp1', _ => $.first($.not(-(2 ** 30))))).eventually.to.deep.equal(2 ** 30 - 1)
+      await expect(database.eval('temp1', _ => $.first($.or(-(2 ** 30), 1)))).eventually.to.deep.equal(-(2 ** 30) + 1)
+
+      await expect(database.eval('temp1', _ => $.first($.xor(2, 3, 6)))).eventually.to.deep.equal(7)
+      await expect(database.eval('temp1', _ => $.first($.xor(true, false)))).eventually.to.deep.equal(true)
+      await expect(database.eval('temp1', _ => $.first($.xor(true, false, true)))).eventually.to.deep.equal(false)
+
+      await expect(database.eval('temp1', _ => $.first($.not(BigInt(2 ** 40))))).eventually.to.deep.equal(BigInt(-(2 ** 40) - 1))
+      await expect(database.eval('temp1', _ => $.first($.and(9223372036854775701n, 9223372036854775702n)))).eventually.to.deep.equal(9223372036854775700n)
+      await expect(database.eval('temp1', _ => $.first($.or(9223372036854775701n, 1n)))).eventually.to.deep.equal(9223372036854775701n)
+      await expect(database.eval('temp1', _ => $.first($.xor(9223372036854775701n, 9223372036854775702n)))).eventually.to.deep.equal(3n)
+      await expect(database.eval('temp1', _ => $.first($.not(9223372036854775701n)))).eventually.to.deep.equal(-9223372036854775702n)
     })
   }