[FIR] Report empty intersection on responsible call

When reporting INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION, search for a call to a declaration with the type parameter that got inferred into an empty intersection inside the expression. #KT-56377 Fixed
2023-06-20 09:44:48 +02:00
parent 3f58782273
commit 585d4b3098
13 changed files with 187 additions and 8 deletions
@@ -0,0 +1,41 @@
+interface I
+open class C
+
+fun completed(): String = "..."
+
+fun <T> incomplete(): T = null!!
+
+fun <T : I> incompatibleI(): T = null!!
+fun <T : C> incompatibleC(): T = null!!
+
+val p = false
+
+fun expectUnit(x: Unit) = x
+
+fun test1() = run {
+    if (p) return@run
+    completed() // ok, not returned
+}
+
+fun test2() = run {
+    if (p) return@run
+    incomplete() // ? either uninferred T or Unit
+}
+
+fun test3() = run {
+    if (p) return@run
+    <!INFERRED_TYPE_VARIABLE_INTO_POSSIBLE_EMPTY_INTERSECTION!>incompatibleI<!>() // ? either uninferred T or error (Unit </: I)
+}
+
+fun test4() = run {
+    if (p) return@run
+    <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>incompatibleC<!>() // ? either uninferred T or error (Unit </: C)
+}
+
+fun main() {
+    // all ok
+    expectUnit(test1())
+    expectUnit(test2())
+    expectUnit(test3())
+    expectUnit(test4())
+}
@@ -1,4 +1,3 @@
-// FIR_IDENTICAL
 interface I
 open class C

@@ -0,0 +1,12 @@
+// !LANGUAGE: -ForbidInferringTypeVariablesIntoEmptyIntersection
+// RENDER_DIAGNOSTICS_FULL_TEXT
+open class Foo
+inline fun <reified T : Foo> g(): T? = null
+
+inline fun <R> f(block: ()->R?): R? {
+    return block()
+}
+
+fun main() {
+    f<Int> { <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>g<!>() }
+}
@@ -1,4 +1,3 @@
-// FIR_IDENTICAL
 // !LANGUAGE: -ForbidInferringTypeVariablesIntoEmptyIntersection
 // RENDER_DIAGNOSTICS_FULL_TEXT
 open class Foo
@@ -0,0 +1,8 @@
+// !LANGUAGE: -ForbidInferringTypeVariablesIntoEmptyIntersection
+fun <T : <!FINAL_UPPER_BOUND!>String<!>> g(): T? = null
+
+fun <R> f(block: () -> R?): R? = block()
+
+fun main() {
+    f<Int> { <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>g<!>() /* OK, g() is inferred into {Int & String}? */ }
+}
@@ -1,4 +1,3 @@
-// FIR_IDENTICAL
 // !LANGUAGE: -ForbidInferringTypeVariablesIntoEmptyIntersection
 fun <T : <!FINAL_UPPER_BOUND!>String<!>> g(): T? = null

@@ -13,7 +13,7 @@ fun <T: A> emptyNullableListOfA(): List<T>? = null

 fun testExclExcl() {
    <!INFERRED_TYPE_VARIABLE_INTO_POSSIBLE_EMPTY_INTERSECTION("T; a/A, kotlin/Int; final class and interface")!>doList<!>(emptyNullableListOfA()!!) //should be an error here
-    val l: List<Int> = <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.collections.List<a.A & kotlin.Int>")!><!INFERRED_TYPE_VARIABLE_INTO_POSSIBLE_EMPTY_INTERSECTION!>id<!>(emptyNullableListOfA()!!)<!>
+    val l: List<Int> = <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.collections.List<a.A & kotlin.Int>")!>id(<!INFERRED_TYPE_VARIABLE_INTO_POSSIBLE_EMPTY_INTERSECTION!>emptyNullableListOfA<!>()!!)<!>

    doList(strangeNullableList { doInt(it) }!!) //lambda should be analyzed (at completion phase)
 }
@@ -0,0 +1,34 @@
+// !LANGUAGE: +ForbidInferringTypeVariablesIntoEmptyIntersection
+// FILE: ObjectNode.java
+
+public interface ObjectNode {
+    <T extends JsonNode> T set(String fieldName, JsonNode value);
+}
+
+// FILE: JsonNode.java
+
+public class JsonNode
+
+// FILE: test.kt
+
+interface JsonObject
+class SomeJsonObject() : JsonObject
+
+fun String.put(value: JsonObject?, node: ObjectNode) {
+    select(
+        node.<!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_ERROR!>set<!>(this, null),
+        Unit,
+    )
+
+    if (value == null) node.<!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_ERROR!>set<!>(this, null)
+    else if (value is SomeJsonObject) Unit
+
+    when (value) {
+        null -> node.<!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_ERROR!>set<!>(this, null)
+        is SomeJsonObject -> Unit
+        else -> TODO()
+    }
+}
+
+fun TODO(): Nothing = null!!
+fun <K> select(vararg values: K): K = values[0]
@@ -1,4 +1,3 @@
-// FIR_IDENTICAL
 // !LANGUAGE: +ForbidInferringTypeVariablesIntoEmptyIntersection
 // FILE: ObjectNode.java

@@ -16,6 +15,14 @@ interface JsonObject
 class SomeJsonObject() : JsonObject

 fun String.put(value: JsonObject?, node: ObjectNode) {
+    <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_ERROR!>select<!>(
+        node.set(this, null),
+        Unit,
+    )
+
+    <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_ERROR!>if (value == null) node.set(this, null)
+    else if (value is SomeJsonObject) Unit<!>
+
    <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_ERROR!>when (value) {
        null -> node.set(this, null)
        is SomeJsonObject -> Unit
@@ -24,3 +31,4 @@ fun String.put(value: JsonObject?, node: ObjectNode) {
 }

 fun TODO(): Nothing = null!!
+fun <K> select(vararg values: K): K = values[0]
@@ -1,6 +1,7 @@
 package

 public fun TODO(): kotlin.Nothing
+public fun </*0*/ K> select(/*0*/ vararg values: K /*kotlin.Array<out K>*/): K
 public fun kotlin.String.put(/*0*/ value: JsonObject?, /*1*/ node: ObjectNode): kotlin.Unit

 public open class JsonNode {
@@ -0,0 +1,35 @@
+// !LANGUAGE: -ForbidInferringTypeVariablesIntoEmptyIntersection
+// FILE: ObjectNode.java
+
+public interface ObjectNode {
+    <T extends JsonNode> T set(String fieldName, JsonNode value);
+}
+
+// FILE: JsonNode.java
+
+public class JsonNode
+
+// FILE: test.kt
+
+interface JsonObject
+class SomeJsonObject() : JsonObject
+
+fun String.put(value: JsonObject?, node: ObjectNode) {
+    select(
+        node.<!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>set<!>(this, null),
+        Unit,
+    )
+
+    if (value == null) node.<!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>set<!>(this, null)
+    else if (value is SomeJsonObject) Unit
+
+    when (value) {
+        null -> node.<!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>set<!>(this, null)
+        is SomeJsonObject -> Unit
+        else -> TODO()
+    }
+}
+
+fun TODO(): Nothing = null!!
+fun <K> select(vararg values: K): K = values[0]
+
@@ -1,4 +1,3 @@
-// FIR_IDENTICAL
 // !LANGUAGE: -ForbidInferringTypeVariablesIntoEmptyIntersection
 // FILE: ObjectNode.java

@@ -16,6 +15,14 @@ interface JsonObject
 class SomeJsonObject() : JsonObject

 fun String.put(value: JsonObject?, node: ObjectNode) {
+    <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>select<!>(
+        node.set(this, null),
+        Unit,
+    )
+
+    <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>if (value == null) node.set(this, null)
+    else if (value is SomeJsonObject) Unit<!>
+
    <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>when (value) {
        null -> node.set(this, null)
        is SomeJsonObject -> Unit
@@ -24,3 +31,5 @@ fun String.put(value: JsonObject?, node: ObjectNode) {
 }

 fun TODO(): Nothing = null!!
+fun <K> select(vararg values: K): K = values[0]
+