Extract to own file

ayrton · ayrton · commit 76377054f16d · 2024-04-25T22:59:51.000+02:00
diff --git a/__tests__/cast.test.ts b/__tests__/cast.test.ts
@@ -0,0 +1,243 @@
+import { cast } from '../src/cast'
+
+describe('cast', () => {
+  test('casts NULL values', () => {
+    expect(
+      cast(
+        {
+          name: 'email',
+          type: 'VARCHAR',
+          table: 'users',
+          orgTable: 'users',
+          database: 'database-js',
+          orgName: 'email',
+          columnLength: 1020,
+          charset: 255
+        },
+        null
+      )
+    ).toEqual(null)
+  })
+
+  test('casts INT64, UINT64 values', () => {
+    expect(
+      cast(
+        {
+          name: 'id',
+          type: 'UINT64',
+          table: 'users',
+          orgTable: 'users',
+          database: 'database-js',
+          orgName: 'id',
+          columnLength: 20,
+          charset: 63,
+          flags: 49699
+        },
+        '1'
+      )
+    ).toEqual('1')
+  })
+
+  test('casts DECIMAL values', () => {
+    expect(
+      cast(
+        {
+          name: 'decimal',
+          type: 'DECIMAL',
+          table: 'decimals',
+          orgTable: 'decimals',
+          database: 'blob',
+          orgName: 'decimal',
+          columnLength: 12,
+          charset: 63,
+          decimals: 2,
+          flags: 32768
+        },
+        '5.4'
+      )
+    ).toEqual('5.4')
+  })
+
+  test('casts DATETIME, DATE, TIMESTAMP, TIME values', () => {
+    expect(
+      cast(
+        {
+          name: 'created_at',
+          type: 'DATETIME',
+          table: 'users',
+          orgTable: 'users',
+          database: 'database-js',
+          orgName: 'created_at',
+          columnLength: 19,
+          charset: 63,
+          flags: 128
+        },
+        '2024-01-01 00:00:00'
+      )
+    ).toEqual('2024-01-01 00:00:00')
+  })
+
+  test('casts JSON values', () => {
+    expect(
+      cast(
+        {
+          name: 'metadata',
+          type: 'JSON',
+          table: 'users',
+          orgTable: 'users',
+          database: 'database-js',
+          orgName: 'metadata',
+          columnLength: 4294967295,
+          charset: 63,
+          flags: 144
+        },
+        '{ "color": "blue" }'
+      )
+    ).toStrictEqual({ color: 'blue' })
+  })
+
+  test('casts INT8, UINT8, INT16, UINT16, INT24, UINT24, INT32, UINT32, INT64, UINT64, YEAR values', () => {
+    expect(
+      cast(
+        {
+          name: 'verified',
+          type: 'INT8',
+          table: 'users',
+          orgTable: 'users',
+          database: 'database-js',
+          orgName: 'verified',
+          columnLength: 1,
+          charset: 63,
+          flags: 32768
+        },
+        '1'
+      )
+    ).toEqual(1)
+    expect(
+      cast(
+        {
+          name: 'age',
+          type: 'INT32',
+          table: 'users',
+          orgTable: 'users',
+          database: 'database-js',
+          orgName: 'age',
+          columnLength: 11,
+          charset: 63,
+          flags: 32768
+        },
+        '21'
+      )
+    ).toEqual(21)
+  })
+
+  test('casts FLOAT32, FLOAT64 values', () => {
+    expect(
+      cast(
+        {
+          name: 'float',
+          type: 'FLOAT32',
+          table: 'decimals',
+          orgTable: 'decimals',
+          database: 'blob',
+          orgName: 'float',
+          columnLength: 12,
+          charset: 63,
+          decimals: 31,
+          flags: 32768
+        },
+        '20.4'
+      )
+    ).toEqual(20.4)
+    expect(
+      cast(
+        {
+          name: 'double',
+          type: 'FLOAT64',
+          table: 'decimals',
+          orgTable: 'decimals',
+          database: 'blob',
+          orgName: 'double',
+          columnLength: 22,
+          charset: 63,
+          decimals: 31,
+          flags: 32768
+        },
+        '101.4'
+      )
+    ).toEqual(101.4)
+  })
+
+  test('casts VARCHAR values', () => {
+    expect(
+      cast(
+        {
+          name: 'email',
+          type: 'VARCHAR',
+          table: 'users',
+          orgTable: 'users',
+          database: 'database-js',
+          orgName: 'email',
+          columnLength: 1020,
+          charset: 255
+        },
+        'user@planetscale.com'
+      )
+    ).toEqual('user@planetscale.com')
+  })
+
+  test('casts BLOB, BIT, GEOMETRY, BINARY, VARBINARY values', () => {
+    /** See e2e tests for more complete assertions */
+
+    expect(
+      cast(
+        {
+          name: 'bytes',
+          type: 'BLOB',
+          table: 'binary_test',
+          orgTable: 'binary_test',
+          database: 'database-js',
+          orgName: 'bytes',
+          columnLength: 4294967295,
+          charset: 63,
+          flags: 4241
+        },
+        '\u0001\u0002\u0003'
+      )
+    ).toEqual(new Uint8Array([1, 2, 3]))
+  })
+
+  test('casts BINARY, VARBINARY string values', () => {
+    /** See e2e tests for more complete assertions */
+
+    expect(
+      cast(
+        {
+          name: 'Index_type',
+          type: 'VARBINARY',
+          table: 'SHOW_STATISTICS',
+          orgName: 'Index_type',
+          columnLength: 44,
+          charset: 255,
+          flags: 129
+        },
+        'BTREE'
+      )
+    ).toEqual('BTREE')
+    expect(
+      cast(
+        {
+          name: 'Tables_in_users',
+          type: 'VARBINARY',
+          table: 'TABLES',
+          orgTable: 'tables',
+          orgName: 'Tables_in_users',
+          columnLength: 256,
+          charset: 255,
+          flags: 4225
+        },
+        'users'
+      )
+    ).toEqual('users')
+  })
+})
diff --git a/__tests__/index.test.ts b/__tests__/index.test.ts
@@ -626,31 +626,6 @@ describe('hex', () => {
   })
 })
 
-describe('cast', () => {
-  test('casts int to number', () => {
-    expect(cast({ name: 'test', type: 'INT8' }, '12')).toEqual(12)
-  })
-
-  test('casts float to number', () => {
-    expect(cast({ name: 'test', type: 'FLOAT32' }, '2.32')).toEqual(2.32)
-    expect(cast({ name: 'test', type: 'FLOAT64' }, '2.32')).toEqual(2.32)
-  })
-
-  test('casts binary data to array of 8-bit unsigned integers', () => {
-    expect(cast({ name: 'test', type: 'BLOB', charset: 63 }, '')).toEqual(new Uint8Array([]))
-    expect(cast({ name: 'test', type: 'BLOB', charset: 63 }, 'Å')).toEqual(new Uint8Array([197]))
-    expect(cast({ name: 'test', type: 'VARBINARY', charset: 63 }, 'Å')).toEqual(new Uint8Array([197]))
-  })
-
-  test('casts binary text data to text', () => {
-    expect(cast({ name: 'test', type: 'VARBINARY', charset: 255 }, 'table')).toEqual('table')
-  })
-
-  test('casts JSON string to JSON object', () => {
-    expect(cast({ name: 'test', type: 'JSON' }, '{ "foo": "bar" }')).toStrictEqual({ foo: 'bar' })
-  })
-})
-
 describe('parse e2e', () => {
   test('golden (testdb.json)', async () => {
     const mockResponse = {
diff --git a/src/cast.ts b/src/cast.ts
@@ -0,0 +1,96 @@
+import type { Field } from './index.js'
+import { decodeUTF8, uint8Array } from './text.js'
+
+/**
+ * https://github.com/vitessio/vitess/blame/v19.0.3/go/mysql/json/helpers.go#L86-L112
+ */
+
+export function cast(field: Field, value: any): any {
+  if (value == null) {
+    return value
+  }
+
+  if (isBigInt(field)) {
+    return value
+  }
+
+  if (isDateOrTime(field)) {
+    return value
+  }
+
+  if (isDecimal(field)) {
+    return value
+  }
+
+  if (isJson(field)) {
+    return JSON.parse(value)
+  }
+
+  if (isIntegral(field)) {
+    return parseInt(value, 10)
+  }
+
+  if (isFloat(field)) {
+    return parseFloat(value)
+  }
+
+  if (isBinary(field)) {
+    return uint8Array(value)
+  }
+
+  return decodeUTF8(value)
+}
+
+/**
+ * These are integral, but we want to leave the `BigInt` casting to the caller.
+ *
+ * https://github.com/planetscale/database-js/pull/90
+ */
+
+function isBigInt(field: Field) {
+  return field.type === 'INT64' || field.type === 'UINT64'
+}
+
+/**
+ * https://github.com/vitessio/vitess/blob/v19.0.3/go/sqltypes/type.go#L103-L106
+ */
+
+function isDateOrTime(field: Field) {
+  return field.type === 'DATETIME' || field.type === 'DATE' || field.type === 'TIMESTAMP' || field.type === 'TIME'
+}
+
+function isDecimal(field: Field) {
+  return field.type === 'DECIMAL'
+}
+
+function isJson(field: Field) {
+  return field.type === 'JSON'
+}
+
+const INTEGRAL_FIELD_TYPES = ['INT8', 'INT16', 'INT24', 'INT32', 'UINT8', 'UINT16', 'UINT24', 'UINT32', 'YEAR']
+
+function isIntegral(field: Field) {
+  return INTEGRAL_FIELD_TYPES.includes(field.type)
+}
+
+const FLOAT_FIELD_TYPES = ['FLOAT32', 'FLOAT64']
+
+function isFloat(field: Field) {
+  return FLOAT_FIELD_TYPES.includes(field.type)
+}
+
+/**
+ * https://github.com/vitessio/vitess/blob/v19.0.3/go/mysql/collations/env.go#L190-L198
+ */
+
+enum Charsets {
+  Utf8mb3ID = 33,
+  Utf8mb4ID = 255,
+  BinaryID = 63,
+  Utf8mb4BinID = 46,
+  Latin1Swedish = 8
+}
+
+function isBinary(field: Field) {
+  return field.charset === Charsets.BinaryID
+}
diff --git a/src/index.ts b/src/index.ts
