Review issues: add KDocs, update .editorconfig

.editorconfig

@@ -40,6 +40,7 @@ ij_kotlin_spaces_around_logical_operators = true
 ij_kotlin_spaces_around_equality_operators = true
 ij_any_align_group_field_declarations = false
 ij_java_align_group_field_declarations = false
+ij_kotlin_line_break_after_multiline_when_entry = false
 
 [{.github/**/*.yml, .idea/*.xml}]
 indent_size = 2

exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/ColumnType.kt

@@ -316,6 +316,16 @@ open class ColumnWithTransform<Unwrapped, Wrapped>(
     val transformer: ColumnTransformer<Unwrapped, Wrapped>
 ) : ColumnType<Wrapped & Any>() {
 
+    /**
+     * Recursively unwraps the given value by applying the delegate's transformation.
+     *
+     * This method will recursively call unwrap on the inner delegate if the delegate
+     * is also an instance of [ColumnWithTransform]. This is useful for handling nested
+     * transformations.
+     *
+     * @param value The value to unwrap. Could be null.
+     * @return The unwrapped value. Returns the value transformed by the transformer if it's not null.
+     */
     open fun unwrapRecursive(value: Wrapped?): Any? {
         return if (delegate is ColumnWithTransform<*, *>) {
             (delegate as ColumnWithTransform<Any, Unwrapped>).unwrapRecursive(transformer.unwrap(value as Wrapped))
@@ -324,6 +334,15 @@ open class ColumnWithTransform<Unwrapped, Wrapped>(
         }
     }
 
+    /**
+     * Gets the original column type that this column with transformation wraps around.
+     *
+     * This property will recursively unwrap the delegate column type if the delegate
+     * is also an instance of [ColumnWithTransform]. This ensures that you get the
+     * original column type, regardless of the number of nested transformations.
+     *
+     * @return The original column's [IColumnType].
+     */
     val originalColumnType: IColumnType<Any>
         get() = when {
             delegate is ColumnWithTransform<*, *> -> delegate.originalColumnType
@@ -371,6 +390,18 @@ open class NullableColumnWithTransform<Unwrapped, Wrapped>(
     delegate: IColumnType<Unwrapped & Any>,
     transformer: ColumnTransformer<Unwrapped, Wrapped>
 ) : ColumnWithTransform<Unwrapped, Wrapped>(delegate, transformer) {
+    /**
+     * Recursively unwraps the given value by applying the delegate's transformation.
+     *
+     * This method will recursively call unwrap on the inner delegate if the delegate
+     * is also an instance of [ColumnWithTransform]. This is useful for handling nested
+     * transformations. Unlike [ColumnWithTransform.unwrapRecursive], this method allows
+     * transformation involving `null` values.
+     *
+     * @param value The value to unwrap. Could be `null`.
+     * @return The unwrapped value. Returns the value transformed by the transformer, which
+     * could be `null` if the transformer design allows it.
+     */
     override fun unwrapRecursive(value: Wrapped?): Any? {
         return if (delegate is ColumnWithTransform<*, *>) {
             (delegate as ColumnWithTransform<Any, Unwrapped>).unwrapRecursive(transformer.unwrap(value as Wrapped))

exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/ResultRow.kt

@@ -176,10 +176,8 @@ class ResultRow(
                 columnType is ColumnWithTransform<*, *> -> {
                     (columnType as ColumnWithTransform<Any, Any>).unwrapRecursive(defaultValueFun!!())
                 }
-
                 else -> defaultValueFun!!()
             }
-
             columnType.nullable -> null
             else -> NotInitializedValue
         }