Code generator redesigned: schemas for marker interfaces are now stored and processed independently from code generation. Supported empty marker interfaces generation and fixed dataframe schema printing for complex dataframes.

Author: nikitinas

src/main/kotlin/org/jetbrains/dataframe/Operations.kt

@@ -339,9 +339,9 @@ internal fun <T> List<T>.splitByIndices(startIndices: Sequence<Int>): Sequence<L
     }
 }
 
-internal fun KClass<*>.createType(typeArgument: KType?) =
-    if (typeArgument != null) createType(listOf(KTypeProjection.invariant(typeArgument)))
-    else createStarProjectedType(false)
+internal fun KClass<*>.createType(typeArgument: KType? = null, nullable: Boolean = false) =
+    if (typeArgument != null) createType(listOf(KTypeProjection.invariant(typeArgument)), nullable)
+    else createStarProjectedType(nullable)
 
 internal inline fun <reified T> createType(typeArgument: KType? = null) = T::class.createType(typeArgument)
 

src/main/kotlin/org/jetbrains/dataframe/api/generateCode.kt

@@ -1,11 +1,23 @@
 package org.jetbrains.dataframe.api
 
 import org.jetbrains.dataframe.DataFrame
-import org.jetbrains.dataframe.impl.codeGen.CodeGeneratorImpl
+import org.jetbrains.dataframe.impl.codeGen.CodeGenerator
+import org.jetbrains.dataframe.internal.schema.extractSchema
 
-inline fun <reified T> DataFrame<T>.generateCode() = generateCode(T::class.simpleName!!)
+inline fun <reified T> DataFrame<T>.generateCode(fields: Boolean = true, extensionProperties: Boolean = true): String {
+    val name = if(T::class.isAbstract)
+        T::class.simpleName!!
+    else "DataEntry"
+    return generateCode(name, fields, extensionProperties)
+}
 
-fun <T> DataFrame<T>.generateCode(markerName: String): String {
-    val codeGen = CodeGeneratorImpl()
-    return codeGen.generateInterfaceDeclarations(this, markerName, generateExtensionProperties = true).joinToString("\n")
+fun <T> DataFrame<T>.generateCode(markerName: String, fields: Boolean = true, extensionProperties: Boolean = true): String {
+    val codeGen = CodeGenerator.create()
+    return codeGen.generate(
+        extractSchema(),
+        markerName,
+        fields = fields,
+        extensionProperties = extensionProperties,
+        isOpen = true,
+    ).first.declarations
 }

src/main/kotlin/org/jetbrains/dataframe/api/schema.kt

@@ -1,7 +1,14 @@
 package org.jetbrains.dataframe
 
-import org.jetbrains.dataframe.impl.codeGen.CodeGeneratorImpl
+import org.jetbrains.dataframe.impl.codeGen.CodeGenerator
+import org.jetbrains.dataframe.internal.schema.extractSchema
 
 fun AnyFrame.schema(markerName: String? = null): String {
-    return CodeGeneratorImpl().generateInterfaceDeclarations(this, markerName ?: "DataRecord", generateExtensionProperties = false).joinToString("\n")
+    return CodeGenerator.create().generate(
+        extractSchema(),
+        markerName ?: "DataRecord",
+        fields = true,
+        extensionProperties = false,
+        isOpen = true
+    ).first.declarations
 }

src/main/kotlin/org/jetbrains/dataframe/api/select.kt

@@ -5,8 +5,8 @@ import org.jetbrains.dataframe.impl.columns.toColumns
 import kotlin.reflect.KProperty
 
 fun <T> DataFrame<T>.select(selector: ColumnsSelector<T, *>): DataFrame<T> = new(this[selector])
-fun <T> DataFrame<T>.select(vararg columns: KProperty<*>) = select { columns.toColumns() }
-fun <T> DataFrame<T>.select(vararg columns: String) = select { columns.toColumns() }
-fun <T> DataFrame<T>.select(vararg columns: Column) = select { columns.toColumns() }
-fun <T> DataFrame<T>.select(columns: Iterable<Column>) = select { columns.toColumnSet() }
+fun <T> DataFrame<T>.select(vararg columns: KProperty<*>): DataFrame<T> = select { columns.toColumns() }
+fun <T> DataFrame<T>.select(vararg columns: String): DataFrame<T> = select { columns.toColumns() }
+fun <T> DataFrame<T>.select(vararg columns: Column): DataFrame<T> = select { columns.toColumns() }
+fun <T> DataFrame<T>.select(columns: Iterable<Column>): DataFrame<T> = select { columns.toColumnSet() }
 

src/main/kotlin/org/jetbrains/dataframe/columns/DataColumn.kt

@@ -2,7 +2,7 @@ package org.jetbrains.dataframe.columns
 
 import org.jetbrains.dataframe.*
 import org.jetbrains.dataframe.impl.asList
-import org.jetbrains.dataframe.impl.schema.DataFrameSchema
+import org.jetbrains.dataframe.internal.schema.DataFrameSchema
 import org.jetbrains.dataframe.impl.columns.MapColumnImpl
 import org.jetbrains.dataframe.impl.columns.FrameColumnImpl
 import org.jetbrains.dataframe.impl.columns.ValueImplColumn

src/main/kotlin/org/jetbrains/dataframe/impl/Rendering.kt

@@ -3,8 +3,8 @@ package org.jetbrains.dataframe.impl
 import org.jetbrains.dataframe.AnyCol
 import org.jetbrains.dataframe.AnyFrame
 import org.jetbrains.dataframe.ColumnKind
-import org.jetbrains.dataframe.impl.schema.ColumnSchema
-import org.jetbrains.dataframe.impl.schema.DataFrameSchema
+import org.jetbrains.dataframe.internal.schema.ColumnSchema
+import org.jetbrains.dataframe.internal.schema.DataFrameSchema
 import org.jetbrains.dataframe.impl.columns.asGroup
 import org.jetbrains.dataframe.impl.columns.asTable