test: add tests for getFieldData() type

[kenjis]

Needs #8480

Description

• add tests for the current behaviors

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide

[kenjis]

I've found there are two getFieldData() methods.
It is documented in https://codeigniter4.github.io/CodeIgniter4/database/metadata.html#db-getfielddata

--- a/tests/system/Database/Live/MySQLi/GetFieldDataTest.php
+++ b/tests/system/Database/Live/MySQLi/GetFieldDataTest.php
@@ -117,7 +117,7 @@ final class GetFieldDataTest extends AbstractGetFieldDataTest
     {
         $this->createTableForType();
 
-        $fields = $this->db->getFieldData($this->table);
+        $fields = $this->db->table($this->table)->get()->getFieldData();
 
         $expected = [
             0 => (object) [

But ResultInterface::getFieldData() returns different data.

$ vendor/bin/phpunit tests/system/Database/Live/MySQLi/GetFieldDataTest.php
PHPUnit 9.6.16 by Sebastian Bergmann and contributors.

Runtime:       PHP 8.2.15
Configuration: /Users/kenji/work/codeigniter/official/CodeIgniter4/phpunit.xml

.F                                                                                          2 / 2 (100%)

Time: 00:00.735, Memory: 18.00 MB

There was 1 failure:

1) CodeIgniter\Database\Live\MySQLi\GetFieldDataTest::testGetFieldDataType
Failed asserting that two arrays are identical.
--- Expected
+++ Actual
@@ @@
 Array &0 (
     0 => Array &1 (
         'name' => 'id'
-        'type' => 'int'
-        'max_length' => null
-        'nullable' => false
-        'default' => null
-        'primary_key' => 1
+        'type' => 3
+        'type_name' => 'long'
+        'max_length' => 0
+        'primary_key' => 2
+        'length' => 20
+        'default' => ''
     )
     1 => Array &2 (
         'name' => 'type_bigint'
-        'type' => 'bigint'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 8
+        'type_name' => 'longlong'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 20
+        'default' => ''
     )
     2 => Array &3 (
         'name' => 'type_blob'
-        'type' => 'blob'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 252
+        'type_name' => 'blob'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 65535
+        'default' => ''
     )
     3 => Array &4 (
         'name' => 'type_boolean'
-        'type' => 'tinyint'
-        'max_length' => 1
-        'nullable' => true
-        'default' => null
+        'type' => 1
+        'type_name' => 'char'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 1
+        'default' => ''
     )
     4 => Array &5 (
         'name' => 'type_char'
-        'type' => 'char'
-        'max_length' => 10
-        'nullable' => true
-        'default' => null
+        'type' => 254
+        'type_name' => 'string'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 30
+        'default' => ''
     )
     5 => Array &6 (
         'name' => 'type_date'
-        'type' => 'date'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 10
+        'type_name' => 'date'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 10
+        'default' => ''
     )
     6 => Array &7 (
         'name' => 'type_datetime'
-        'type' => 'datetime'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 12
+        'type_name' => 'datetime'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 19
+        'default' => ''
     )
     7 => Array &8 (
         'name' => 'type_decimal'
-        'type' => 'decimal'
-        'max_length' => 18
-        'nullable' => true
-        'default' => null
+        'type' => 246
+        'type_name' => 'newdecimal'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 20
+        'default' => ''
     )
     8 => Array &9 (
         'name' => 'type_double'
-        'type' => 'double'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 5
+        'type_name' => 'double'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 22
+        'default' => ''
     )
     9 => Array &10 (
         'name' => 'type_enum'
-        'type' => 'enum'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 254
+        'type_name' => 'string'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 15
+        'default' => ''
     )
     10 => Array &11 (
         'name' => 'type_float'
-        'type' => 'float'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 4
+        'type_name' => 'float'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 12
+        'default' => ''
     )
     11 => Array &12 (
         'name' => 'type_integer'
-        'type' => 'int'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 3
+        'type_name' => 'long'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 11
+        'default' => ''
     )
     12 => Array &13 (
         'name' => 'type_mediumtext'
-        'type' => 'mediumtext'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 252
+        'type_name' => 'blob'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 50331645
+        'default' => ''
     )
     13 => Array &14 (
         'name' => 'type_numeric'
-        'type' => 'decimal'
-        'max_length' => 18
-        'nullable' => true
-        'default' => null
+        'type' => 246
+        'type_name' => 'newdecimal'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 20
+        'default' => ''
     )
     14 => Array &15 (
         'name' => 'type_real'
-        'type' => 'double'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 5
+        'type_name' => 'double'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 22
+        'default' => ''
     )
     15 => Array &16 (
         'name' => 'type_set'
-        'type' => 'set'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 254
+        'type_name' => 'string'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 21
+        'default' => ''
     )
     16 => Array &17 (
         'name' => 'type_smallint'
-        'type' => 'smallint'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 2
+        'type_name' => 'short'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 6
+        'default' => ''
     )
     17 => Array &18 (
         'name' => 'type_text'
-        'type' => 'text'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 252
+        'type_name' => 'blob'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 196605
+        'default' => ''
     )
     18 => Array &19 (
         'name' => 'type_time'
-        'type' => 'time'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 11
+        'type_name' => 'time'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 10
+        'default' => ''
     )
     19 => Array &20 (
         'name' => 'type_timestamp'
-        'type' => 'timestamp'
-        'max_length' => null
-        'nullable' => true
-        'default' => null
+        'type' => 7
+        'type_name' => 'timestamp'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 19
+        'default' => ''
     )
     20 => Array &21 (
         'name' => 'type_varchar'
-        'type' => 'varchar'
-        'max_length' => 40
-        'nullable' => true
-        'default' => null
+        'type' => 253
+        'type_name' => 'var_string'
+        'max_length' => 0
         'primary_key' => 0
+        'length' => 120
+        'default' => ''
     )
 )
...

[kenjis]

Can someone approve?