MDL-69973 xmldb: Fix problem with MariaDB >= 10.2.7 metadata defaults

With MariaDB 10.2.7 the driver was incorrectly returning '' (empty
string) as default for all the columns having null (meaning, no
default).

Also, cover the case in unit tests, it seems that we were already
testing other defaults but not the null case.

diff --git a/lib/dml/mysqli_native_moodle_database.php b/lib/dml/mysqli_native_moodle_database.php
index 599913a..4459502 100644 (file)
--- a/lib/dml/mysqli_native_moodle_database.php
+++ b/lib/dml/mysqli_native_moodle_database.php
@@ -886,7 +886,7 @@ class mysqli_native_moodle_database extends moodle_database {
         $info->type           = $rawcolumn->data_type;
         $info->meta_type      = $this->mysqltype2moodletype($rawcolumn->data_type);
         if ($this->has_breaking_change_quoted_defaults()) {
-            $info->default_value = trim($rawcolumn->column_default, "'");
+            $info->default_value = is_null($rawcolumn->column_default) ? null : trim($rawcolumn->column_default, "'");
             if ($info->default_value === 'NULL') {
                 $info->default_value = null;
             }

diff --git a/lib/dml/tests/dml_test.php b/lib/dml/tests/dml_test.php
index bff9b97..5a36826 100644 (file)
--- a/lib/dml/tests/dml_test.php
+++ b/lib/dml/tests/dml_test.php
@@ -722,9 +722,13 @@ EOD;
         $table->add_field('course', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, '0');
         $table->add_field('name', XMLDB_TYPE_CHAR, '255', null, null, null, 'lala');
         $table->add_field('description', XMLDB_TYPE_TEXT, 'small', null, null, null, null);
+        $table->add_field('oneint', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, '0');
+        $table->add_field('oneintnodefault', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null);
         $table->add_field('enumfield', XMLDB_TYPE_CHAR, '255', null, XMLDB_NOTNULL, null, 'test2');
         $table->add_field('onenum', XMLDB_TYPE_NUMBER, '10,2', null, null, null, 200);
-        $table->add_field('onefloat', XMLDB_TYPE_FLOAT, '10,2', null, null, null, 300);
+        $table->add_field('onenumnodefault', XMLDB_TYPE_NUMBER, '10,2', null, null, null);
+        $table->add_field('onefloat', XMLDB_TYPE_FLOAT, '10,2', null, XMLDB_NOTNULL, null, 300);
+        $table->add_field('onefloatnodefault', XMLDB_TYPE_FLOAT, '10,2', null, XMLDB_NOTNULL, null);
         $table->add_field('anotherfloat', XMLDB_TYPE_FLOAT, null, null, null, null, 400);
         $table->add_field('negativedfltint', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, '-1');
         $table->add_field('negativedfltnumber', XMLDB_TYPE_NUMBER, '10', null, XMLDB_NOTNULL, null, '-2');
@@ -785,6 +789,20 @@ EOD;
         $this->assertNull($field->default_value);
         $this->assertFalse($field->not_null);
 
+        $field = $columns['oneint'];
+        $this->assertSame('I', $field->meta_type);
+        $this->assertFalse($field->auto_increment);
+        $this->assertTrue($field->has_default);
+        $this->assertEquals(0, $field->default_value);
+        $this->assertTrue($field->not_null);
+
+        $field = $columns['oneintnodefault'];
+        $this->assertSame('I', $field->meta_type);
+        $this->assertFalse($field->auto_increment);
+        $this->assertFalse($field->has_default);
+        $this->assertNull($field->default_value);
+        $this->assertTrue($field->not_null);
+
         $field = $columns['enumfield'];
         $this->assertSame('C', $field->meta_type);
         $this->assertFalse($field->auto_increment);
@@ -800,12 +818,28 @@ EOD;
         $this->assertEquals(200.0, $field->default_value);
         $this->assertFalse($field->not_null);
 
+        $field = $columns['onenumnodefault'];
+        $this->assertSame('N', $field->meta_type);
+        $this->assertFalse($field->auto_increment);
+        $this->assertEquals(10, $field->max_length);
+        $this->assertEquals(2, $field->scale);
+        $this->assertFalse($field->has_default);
+        $this->assertNull($field->default_value);
+        $this->assertFalse($field->not_null);
+
         $field = $columns['onefloat'];
         $this->assertSame('N', $field->meta_type);
         $this->assertFalse($field->auto_increment);
         $this->assertTrue($field->has_default);
         $this->assertEquals(300.0, $field->default_value);
-        $this->assertFalse($field->not_null);
+        $this->assertTrue($field->not_null);
+
+        $field = $columns['onefloatnodefault'];
+        $this->assertSame('N', $field->meta_type);
+        $this->assertFalse($field->auto_increment);
+        $this->assertFalse($field->has_default);
+        $this->assertNull($field->default_value);
+        $this->assertTrue($field->not_null);
 
         $field = $columns['anotherfloat'];
         $this->assertSame('N', $field->meta_type);