Kotlin: Extract error expression for enumValues<T> calls

Author: tamasvajk

java/kotlin-extractor/src/main/kotlin/KotlinFileExtractor.kt

@@ -1778,13 +1778,34 @@ open class KotlinFileExtractor(
                     return
                 }
 
-                val func = ((c.getTypeArgument(0) as? IrSimpleType)?.classifier?.owner as? IrClass)?.declarations?.findSubType<IrFunction> { it.name.asString() == fnName }
-                if (func == null) {
-                    logger.errorElement("Couldn't find function $fnName on enum type", c)
+                val enumType = (c.getTypeArgument(0) as? IrSimpleType)?.classifier?.owner
+                if (enumType == null) {
+                    logger.errorElement("Couldn't find type of enum type", c)
                     return
                 }
 
-                extractMethodAccess(func, false)
+                if (enumType is IrClass) {
+                    val func = enumType.declarations.findSubType<IrFunction> { it.name.asString() == fnName }
+                    if (func == null) {
+                        logger.errorElement("Couldn't find function $fnName on enum type", c)
+                        return
+                    }
+
+                    extractMethodAccess(func, false)
+                } else if (enumType is IrTypeParameter && enumType.isReified) {
+                    // A call to `enumValues<T>()` is being extracted, where `T` is a reified type parameter of an `inline` function.
+                    // We can't generate a valid expression here, because we would need to know the type of T on the call site.
+                    val id = tw.getFreshIdLabel<DbErrorexpr>()
+                    val type = useType(c.type)
+
+                    tw.writeExprs_errorexpr(id, type.javaResult.id, parent, idx)
+                    tw.writeExprsKotlinType(id, type.kotlinResult.id)
+                    tw.writeHasLocation(id, tw.getLocation(c))
+                    tw.writeCallableEnclosingExpr(id, callable)
+                    tw.writeStatementEnclosingExpr(id, enclosingStmt)
+                } else {
+                    logger.errorElement("Unexpected enum type rep ${enumType.javaClass}", c)
+                }
             }
 
             fun binopReceiver(id: Label<out DbExpr>, receiver: IrExpression?, receiverDescription: String) {

java/ql/test/kotlin/library-tests/exprs/PrintAst.expected

@@ -2839,6 +2839,7 @@ exprs.kt:
 #  272|         0: [TypeAccess] T
 #  272|       5: [BlockStmt] { ... }
 #  272|         0: [ReturnStmt] return ...
+#  272|           0: [ErrorExpr] <error expr>
 #  274|     13: [Method] callToEnumValues
 #  274|       3: [TypeAccess] Unit
 #  274|       5: [BlockStmt] { ... }

java/ql/test/kotlin/library-tests/exprs/exprs.expected

@@ -1725,6 +1725,7 @@
 | exprs.kt:268:14:268:14 | 1 | exprs.kt:261:1:270:1 | inPlaceOperators | IntegerLiteral |
 | exprs.kt:272:8:272:66 | T | file://:0:0:0:0 | <none> | TypeAccess |
 | exprs.kt:272:8:272:66 | T[] | file://:0:0:0:0 | <none> | TypeAccess |
+| exprs.kt:272:52:272:66 | <error expr> | exprs.kt:272:8:272:66 | getEnumValues | ErrorExpr |
 | exprs.kt:274:1:277:1 | Unit | file://:0:0:0:0 | <none> | TypeAccess |
 | exprs.kt:275:5:275:23 | <implicit coercion to unit> | exprs.kt:274:1:277:1 | callToEnumValues | ImplicitCoercionToUnitExpr |
 | exprs.kt:275:5:275:23 | Color | exprs.kt:274:1:277:1 | callToEnumValues | TypeAccess |