Remove Kotlin element and component type from arrays

Now that these are no longer required, array extraction can extract kt-types consistently with other parameterised classes.
2026-04-30 19:26:02 +02:00 · 2021-11-12 15:07:06 +00:00
parent 70294bd26b
commit 1b7e33b6e3
6 changed files with 70 additions and 60 deletions
--- a/java/kotlin-extractor/src/main/kotlin/KotlinExtractorExtension.kt
+++ b/java/kotlin-extractor/src/main/kotlin/KotlinExtractorExtension.kt
@@ -25,6 +25,7 @@ import java.util.zip.GZIPOutputStream
 import com.semmle.extractor.java.OdasaOutput
 import com.semmle.extractor.java.OdasaOutput.TrapFileManager
 import com.semmle.util.files.FileUtil
+import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
 import org.jetbrains.kotlin.ir.types.impl.makeTypeProjection
 import org.jetbrains.kotlin.ir.util.*
 import kotlin.system.exitProcess
@@ -372,6 +373,8 @@ open class KotlinUsesExtractor(
               d.origin == IrDeclarationOrigin.IR_EXTERNAL_JAVA_DECLARATION_STUB
    }

+    fun isArray(t: IrSimpleType) = t.isBoxedArray || t.isPrimitiveArray()
+
    fun extractClassLaterIfExternal(c: IrClass) {
        if (isExternalDeclaration(c)) {
            extractExternalClassLater(c)
@@ -410,7 +413,7 @@ open class KotlinUsesExtractor(
                        else
                            primitiveInfo.primitiveName

-                    type.isBoxedArray || type.isPrimitiveArray() -> {
+                    isArray(type) -> {
                        val elementType = type.getArrayElementType(pluginContext.irBuiltIns)
                        val javaElementType = if (type.isPrimitiveArray()) elementType else elementType.makeNullable()
                        shortName(javaElementType) + "[]"
@@ -520,22 +523,52 @@ open class KotlinUsesExtractor(
        return TypeResults(javaResult, kotlinResult)
    }

-    fun useArrayType(arrayType: IrSimpleType, componentType: IrType, elementType: IrType, dimensions: Int): TypeResults {
+    // Given either a primitive array or a boxed array, returns primitive arrays unchanged,
+    // but returns boxed arrays with a nullable, invariant component type, with any nested arrays
+    // similarly transformed. For example, Array<out Array<in E>> would become Array<Array<E?>?>
+    // Array<*> will become Array<Any?>.
+    fun getInvariantNullableArrayType(arrayType: IrSimpleType): IrSimpleType =
+        if (arrayType.isPrimitiveArray())
+            arrayType
+        else {
+            val componentType = arrayType.getArrayElementType(pluginContext.irBuiltIns)
+            val componentTypeBroadened = when (componentType) {
+                is IrSimpleType ->
+                    if (isArray(componentType)) getInvariantNullableArrayType(componentType) else componentType
+                else -> componentType
+            }
+            val unchanged =
+                componentType == componentTypeBroadened &&
+                        (arrayType.arguments[0] as? IrTypeProjection)?.variance == Variance.INVARIANT &&
+                        componentType.isNullable()
+            if (unchanged)
+                arrayType
+            else
+                IrSimpleTypeImpl(
+                    arrayType.classifier,
+                    true,
+                    listOf(makeTypeProjection(componentTypeBroadened, Variance.INVARIANT)),
+                    listOf()
+                )
+        }
+
+    fun useArrayType(arrayType: IrSimpleType, componentType: IrType, elementType: IrType, dimensions: Int, isPrimitiveArray: Boolean): TypeResults {
+
+        // Ensure we extract Array<Int> as Integer[], not int[], for example:
+        fun nullableIfNotPrimitive(type: IrType) = if (type.isPrimitiveType() && !isPrimitiveArray) type.makeNullable() else type

        // TODO: Figure out what signatures should be returned

-        val componentTypeLabels = useType(componentType)
-        val elementTypeLabels = useType(elementType)
+        val componentTypeLabel = useType(nullableIfNotPrimitive(componentType)).javaResult.id
+        val elementTypeLabel = useType(nullableIfNotPrimitive(elementType)).javaResult.id

-        val id = tw.getLabelFor<DbArray>("@\"array;$dimensions;{${elementTypeLabels.javaResult.id}}\"") {
+        val id = tw.getLabelFor<DbArray>("@\"array;$dimensions;{${elementTypeLabel}}\"") {
            tw.writeArrays(
                it,
                shortName(arrayType),
-                elementTypeLabels.javaResult.id,
-                elementTypeLabels.kotlinResult.id,
+                elementTypeLabel,
                dimensions,
-                componentTypeLabels.javaResult.id,
-                componentTypeLabels.kotlinResult.id)
+                componentTypeLabel)

            extractClassCommon(arrayType.classifier.owner as IrClass, it)

@@ -546,29 +579,23 @@ open class KotlinUsesExtractor(
            // TODO: modifiers
            // tw.writeHasModifier(length, getModifierKey("public"))
            // tw.writeHasModifier(length, getModifierKey("final"))
-        }

-        val javaSignature = "an array" // TODO: Wrong
-        val javaResult = TypeResult(id, javaSignature)
-        // Note the stripping of any type projection from `componentType` here mirrors the action of `IrType.getArrayElementType`,
-        // and is required if we are not to produce different kotlin types for the same Java type (e.g. List[] -> Array<out List> or Array<List>)
-        val owner: IrClass = arrayType.classifier.owner as IrClass
-        val kotlinTypeArgs = if (arrayType.arguments.isEmpty()) listOf() else listOf(makeTypeProjection(componentType, Variance.INVARIANT))
-        val kotlinClassName = getUnquotedClassLabel(owner, kotlinTypeArgs)
-        val kotlinSignature = "$javaSignature?" // TODO: Wrong
-        val kotlinLabel = "@\"kt_type;nullable;${kotlinClassName}\""
-        val kotlinId: Label<DbKt_nullable_type> = tw.getLabelFor(kotlinLabel, {
-            tw.writeKt_nullable_types(it, id)
-        })
-        val kotlinResult = TypeResult(kotlinId, kotlinSignature)
+            // Note we will only emit one `clone()` method per Java array type, so we choose `Array<C?>` as its Kotlin
+            // return type, where C is the component type with any nested arrays themselves invariant and nullable.
+            val kotlinCloneReturnType = getInvariantNullableArrayType(arrayType).makeNullable()
+            val kotlinCloneReturnTypeLabel = useType(kotlinCloneReturnType).kotlinResult.id

-        tw.getLabelFor<DbMethod>("@\"callable;{$id}.clone(){$id}\"") {
-            tw.writeMethods(it, "clone", "clone()", javaResult.id, kotlinResult.id, javaResult.id, it)
+            val clone = tw.getLabelFor<DbMethod>("@\"callable;{$it}.clone(){$it}\"")
+            tw.writeMethods(clone, "clone", "clone()", it, kotlinCloneReturnTypeLabel, it, clone)
            // TODO: modifiers
            // tw.writeHasModifier(clone, getModifierKey("public"))
        }

-        return TypeResults(javaResult, kotlinResult)
+        val javaSignature = "an array" // TODO: Wrong
+        val javaResult = TypeResult(id, javaSignature)
+
+        val arrayClassResult = useSimpleTypeClass(arrayType.classifier.owner as IrClass, arrayType.arguments, arrayType.hasQuestionMark)
+        return TypeResults(javaResult, arrayClassResult.kotlinResult)
    }

    fun useSimpleType(s: IrSimpleType, canReturnPrimitiveTypes: Boolean): TypeResults {
@@ -669,13 +696,12 @@ class X {
                    elementType = elementType.getArrayElementType(pluginContext.irBuiltIns)
                }

-                fun nullableUnlessPrimitive(type: IrType) = if (isPrimitiveArray && type.isPrimitiveType()) type else type.makeNullable()
-
                return useArrayType(
                    s,
-                    nullableUnlessPrimitive(componentType),
-                    nullableUnlessPrimitive(elementType),
-                    dimensions
+                    componentType,
+                    elementType,
+                    dimensions,
+                    isPrimitiveArray
                )
            }

--- a/java/ql/lib/config/semmlecode.dbscheme
+++ b/java/ql/lib/config/semmlecode.dbscheme
@@ -512,10 +512,8 @@ arrays(
  unique int id: @array,
  string nodeName: string ref,
  int elementtypeid: @type ref,
-  int elementkttypeid: @kt_type ref,
  int dimension: int ref,
-  int componenttypeid: @type ref,
-  int componentkttypeid: @kt_type ref
+  int componenttypeid: @type ref
 );

 enclInReftype(
--- a/java/ql/lib/semmle/code/Location.qll
+++ b/java/ql/lib/semmle/code/Location.qll
@@ -40,7 +40,7 @@ predicate hasName(Element e, string name) {
  or
  wildcards(e, name, _)
  or
-  arrays(e, name, _, _, _, _, _)
+  arrays(e, name, _, _, _)
  or
  modifiers(e, name)
  or
--- a/java/ql/lib/semmle/code/java/Type.qll
+++ b/java/ql/lib/semmle/code/java/Type.qll
@@ -354,35 +354,21 @@ class Array extends RefType, @array {
   *
   * For example, the component type of `Object[][]` is `Object[]`.
   */
-  Type getComponentType() { arrays(this, _, _, _, _, result, _) }
+  Type getComponentType() { arrays(this, _, _, _, result) }

  /**
-   * Gets the type of the components of this array type.
-   *
-   * For example, the component type of `Object[][]` is `Object[]`.
-   */
-  KotlinType getComponentKotlinType() { arrays(this, _, _, _, _, _, result) }
-
-  /**
-   * Gets the Kotlin type of the elements used to construct this array type.
+   * Gets the type of the elements used to construct this array type.
   *
   * For example, the element type of `Object[][]` is `Object`.
   */
-  Type getElementType() { arrays(this, _, result, _, _, _, _) }
-
-  /**
-   * Gets the Kotlin type of the elements used to construct this array type.
-   *
-   * For example, the element type of `Object[][]` is `Object`.
-   */
-  KotlinType getElementKotlinType() { arrays(this, _, _, result, _, _, _) }
+  Type getElementType() { arrays(this, _, result, _, _) }

  /**
   * Gets the arity of this array type.
   *
   * For example, the dimension of `Object[][]` is 2.
   */
-  int getDimension() { arrays(this, _, _, _, result, _, _) }
+  int getDimension() { arrays(this, _, _, result, _) }

  /**
   * Gets the JVM descriptor for this type, as used in bytecode.
--- a/java/ql/test/kotlin/library-tests/arrays/test.expected
+++ b/java/ql/test/kotlin/library-tests/arrays/test.expected
@@ -1,6 +1,6 @@
-| primitiveArrays.kt:5:12:5:24 | a | file://:0:0:0:0 | Integer[] | file://:0:0:0:0 | Integer | file://:0:0:0:0 | Integer | file://:0:0:0:0 | Kotlin nullable Integer | file://:0:0:0:0 | Kotlin nullable Integer |
-| primitiveArrays.kt:5:27:5:40 | b | file://:0:0:0:0 | Integer[] | file://:0:0:0:0 | Integer | file://:0:0:0:0 | Integer | file://:0:0:0:0 | Kotlin nullable Integer | file://:0:0:0:0 | Kotlin nullable Integer |
-| primitiveArrays.kt:5:43:5:53 | c | file://:0:0:0:0 | int[] | file://:0:0:0:0 | int | file://:0:0:0:0 | int | file://:0:0:0:0 | Kotlin not-null Integer | file://:0:0:0:0 | Kotlin not-null Integer |
-| primitiveArrays.kt:5:56:5:76 | d | file://:0:0:0:0 | Integer[][] | file://:0:0:0:0 | Integer[] | file://:0:0:0:0 | Integer | file://:0:0:0:0 | Kotlin nullable Integer[] | file://:0:0:0:0 | Kotlin nullable Integer |
-| primitiveArrays.kt:5:79:5:98 | e | file://:0:0:0:0 | Integer[][] | file://:0:0:0:0 | Integer[] | file://:0:0:0:0 | Integer | file://:0:0:0:0 | Kotlin nullable Integer[] | file://:0:0:0:0 | Kotlin nullable Integer |
-| primitiveArrays.kt:5:101:5:118 | f | file://:0:0:0:0 | int[][] | file://:0:0:0:0 | int[] | file://:0:0:0:0 | int | file://:0:0:0:0 | Kotlin nullable int[] | file://:0:0:0:0 | Kotlin not-null Integer |
+| primitiveArrays.kt:5:12:5:24 | a | file://:0:0:0:0 | Integer[] | file://:0:0:0:0 | Integer | file://:0:0:0:0 | Integer |
+| primitiveArrays.kt:5:27:5:40 | b | file://:0:0:0:0 | Integer[] | file://:0:0:0:0 | Integer | file://:0:0:0:0 | Integer |
+| primitiveArrays.kt:5:43:5:53 | c | file://:0:0:0:0 | int[] | file://:0:0:0:0 | int | file://:0:0:0:0 | int |
+| primitiveArrays.kt:5:56:5:76 | d | file://:0:0:0:0 | Integer[][] | file://:0:0:0:0 | Integer[] | file://:0:0:0:0 | Integer |
+| primitiveArrays.kt:5:79:5:98 | e | file://:0:0:0:0 | Integer[][] | file://:0:0:0:0 | Integer[] | file://:0:0:0:0 | Integer |
+| primitiveArrays.kt:5:101:5:118 | f | file://:0:0:0:0 | int[][] | file://:0:0:0:0 | int[] | file://:0:0:0:0 | int |
--- a/java/ql/test/kotlin/library-tests/arrays/test.ql
+++ b/java/ql/test/kotlin/library-tests/arrays/test.ql
@@ -2,4 +2,4 @@ import java

 from Parameter p, Array a
 where p.getType() = a and p.getFile().getBaseName() = "primitiveArrays.kt"
-select p, a, a.getComponentType(), a.getElementType(), a.getComponentKotlinType(), a.getElementKotlinType()
+select p, a, a.getComponentType(), a.getElementType()