K2: Add some more tests showing the state for KT-64840

lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt
should show in the future commits how early variable fixation
necessary for bare type information might affect inference results

^KT-64840 Related

compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeAs.fir.kt

@@ -0,0 +1,28 @@
+// ISSUE: KT-64840
+class Controller<T> {
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface A<F> {
+    val a: F
+}
+
+interface B<G> : A<G> {
+    val b: G
+}
+
+fun <X> withCallback(x: X, c: Controller<in X>, p: (X) -> Unit) {}
+
+fun main(a: A<String>) {
+    val x = generate {
+        withCallback(a, this) {
+            (it as <!NO_TYPE_ARGUMENTS_ON_RHS!>B<!>).<!UNRESOLVED_REFERENCE!>b<!>.length
+            it.<!UNRESOLVED_REFERENCE!>b<!>.length
+            it.a.length
+        }
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("A<kotlin.String>")!>x<!>
+}

compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeAs.kt

@@ -0,0 +1,28 @@
+// ISSUE: KT-64840
+class Controller<T> {
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface A<F> {
+    val a: F
+}
+
+interface B<G> : A<G> {
+    val b: G
+}
+
+fun <X> withCallback(x: X, c: Controller<in X>, p: (X) -> Unit) {}
+
+fun main(a: A<String>) {
+    val x = generate {
+        withCallback(a, this) {
+            (it as B).b.length
+            <!DEBUG_INFO_SMARTCAST!>it<!>.b.length
+            it.a.length
+        }
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("A<kotlin.String>")!>x<!>
+}

compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeEarlyFixationAffectsBehavior.fir.kt

@@ -0,0 +1,37 @@
+// !CHECK_TYPE
+// ISSUE: KT-64840
+
+class Controller<T> {
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface CommonSupertype
+interface A<F> : CommonSupertype
+interface B<G> : A<G>
+interface C : CommonSupertype
+
+fun <X> predicate(x: X, c: Controller<X>, p: (X) -> Unit) {}
+
+fun main(a: A<*>, c: C) {
+    val x1 = generate {
+        predicate(a, this) { x ->
+            // x is B
+        }
+
+        yield(c)
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("CommonSupertype")!>x1<!>
+
+    val x2 = generate {
+        predicate(a, this) { x ->
+            x is <!NO_TYPE_ARGUMENTS_ON_RHS!>B<!>
+        }
+
+        yield(c)
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("CommonSupertype")!>x2<!>
+}

compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt

@@ -0,0 +1,37 @@
+// !CHECK_TYPE
+// ISSUE: KT-64840
+
+class Controller<T> {
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface CommonSupertype
+interface A<F> : CommonSupertype
+interface B<G> : A<G>
+interface C : CommonSupertype
+
+fun <X> predicate(x: X, c: Controller<X>, p: (X) -> Unit) {}
+
+fun main(a: A<*>, c: C) {
+    val x1 = generate {
+        predicate(a, this) { x ->
+            // x is B
+        }
+
+        yield(c)
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("CommonSupertype")!>x1<!>
+
+    val x2 = generate {
+        predicate(a, this) { x ->
+            <!USELESS_IS_CHECK!>x is <!NO_TYPE_ARGUMENTS_ON_RHS!>B<!><!>
+        }
+
+        yield(c)
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("CommonSupertype")!>x2<!>
+}

compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeOnOuterTypeVariable.fir.kt

@@ -0,0 +1,20 @@
+// ISSUE: KT-64840
+class Controller<T> {
+    val t: T get() = TODO()
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface A<F> {
+    val a: F?
+}
+
+interface B<G> : A<G>
+
+fun main(a: A<*>) {
+    generate {
+        yield(a)
+        t is <!NO_TYPE_ARGUMENTS_ON_RHS!>B<!>
+    }.a
+}

compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeOnOuterTypeVariable.kt

@@ -0,0 +1,20 @@
+// ISSUE: KT-64840
+class Controller<T> {
+    val t: T get() = TODO()
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface A<F> {
+    val a: F?
+}
+
+interface B<G> : A<G>
+
+fun main(a: A<*>) {
+    generate {
+        yield(a)
+        <!USELESS_IS_CHECK!>t is <!NO_TYPE_ARGUMENTS_ON_RHS!>B<!><!>
+    }.a
+}

compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForNonBareType.fir.kt

@@ -0,0 +1,27 @@
+// ISSUE: KT-64840
+
+class Controller<T> {
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface CommonSupertype
+interface A<F> : CommonSupertype
+interface B : A<String>
+interface C : CommonSupertype
+
+fun <X> predicate(x: X, c: Controller<X>, p: (X) -> Boolean) {}
+
+fun main(a: A<String>, c: C) {
+    val x2 = generate {
+        predicate(a, this) { x ->
+            // USELESS_IS_CHECK is errorenously reported in K1
+            x is B
+        }
+
+        yield(c)
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("CommonSupertype")!>x2<!>
+}

compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForNonBareType.kt

@@ -0,0 +1,27 @@
+// ISSUE: KT-64840
+
+class Controller<T> {
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface CommonSupertype
+interface A<F> : CommonSupertype
+interface B : A<String>
+interface C : CommonSupertype
+
+fun <X> predicate(x: X, c: Controller<X>, p: (X) -> Boolean) {}
+
+fun main(a: A<String>, c: C) {
+    val x2 = generate {
+        predicate(a, this) { x ->
+            // USELESS_IS_CHECK is errorenously reported in K1
+            <!USELESS_IS_CHECK!>x is B<!>
+        }
+
+        yield(c)
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("CommonSupertype")!>x2<!>
+}