Move detecting of illegal call of contract function into call checker

(#KT-26153, #KT-26191) fixed

compiler/testData/diagnostics/testsWithStdLib/contracts/dsl/errors/notFirstStatement.kt

@@ -1,12 +1,76 @@
 // !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect
 // !USE_EXPERIMENTAL: kotlin.contracts.ExperimentalContracts
-// !DIAGNOSTICS: -INVISIBLE_REFERENCE -INVISIBLE_MEMBER
+// !DIAGNOSTICS: -INVISIBLE_REFERENCE -INVISIBLE_MEMBER -UNUSED_VARIABLE -REDUNDANT_LABEL_WARNING -UNUSED_PARAMETER -NOTHING_TO_INLINE -CAST_NEVER_SUCCEEDS
+// Issues: KT-26153, KT-26191
 
 import kotlin.contracts.*
 
 fun foo(y: Boolean) {
-    val <!UNUSED_VARIABLE!>x<!>: Int = 42
+    val x: Int = 42
     <!CONTRACT_NOT_ALLOWED("Contract should be the first statement")!>contract<!> {
         returns() implies y
     }
+}
+
+inline fun case1(block: () -> Unit) {
+    val contracts = listOf(
+        <!CONTRACT_NOT_ALLOWED!>contract<!> {
+            callsInPlace(block, InvocationKind.EXACTLY_ONCE)
+        }, <!CONTRACT_NOT_ALLOWED!>contract<!> {
+            callsInPlace(block, InvocationKind.EXACTLY_ONCE)
+        }
+    )
+    block()
+}
+
+inline fun case_2(block: () -> Unit) = <!CONTRACT_NOT_ALLOWED("Contracts are allowed only in function body block")!>contract<!> {
+    callsInPlace(block, InvocationKind.EXACTLY_ONCE)
+}
+
+fun case_3(block: () -> Unit) {
+    class Class {
+        fun innerFun(block2: () -> Unit) {
+            <!CONTRACT_NOT_ALLOWED("Contracts are allowed only for top-level functions")!>contract<!> {
+                callsInPlace(block2, InvocationKind.EXACTLY_ONCE)
+            }
+            block2()
+        }
+    }
+    return
+}
+
+inline fun case_4(number: Int?): Boolean {
+    val cond = number != null
+    <!CONTRACT_NOT_ALLOWED!>contract<!> {
+        returns(false) implies (cond)
+    } as ContractBuilder
+    return number == null
+}
+
+inline fun case_5(cond: Boolean): Boolean {
+    run {
+        <!CONTRACT_NOT_ALLOWED!>contract<!> {
+            returns(true) implies (cond)
+        }
+    }
+    return true
+}
+
+inline fun case_6(cond: Boolean): Boolean {
+    run {
+        val x = 10
+        <!CONTRACT_NOT_ALLOWED, CONTRACT_NOT_ALLOWED!>contract<!> {
+            returns(true) implies (cond)
+        }
+    }
+    return true
+}
+
+fun case_7(cond: Boolean): Boolean {
+    fun innerFun() {
+        <!CONTRACT_NOT_ALLOWED!>contract<!> {
+            returns(true) implies (cond)
+        }
+    }
+    return true
 }

compiler/testData/diagnostics/testsWithStdLib/contracts/dsl/errors/notFirstStatement.txt

@@ -1,3 +1,10 @@
 package
 
+public inline fun case1(/*0*/ block: () -> kotlin.Unit): kotlin.Unit
+public inline fun case_2(/*0*/ block: () -> kotlin.Unit): kotlin.Unit
+public fun case_3(/*0*/ block: () -> kotlin.Unit): kotlin.Unit
+public inline fun case_4(/*0*/ number: kotlin.Int?): kotlin.Boolean
+public inline fun case_5(/*0*/ cond: kotlin.Boolean): kotlin.Boolean
+public inline fun case_6(/*0*/ cond: kotlin.Boolean): kotlin.Boolean
+public fun case_7(/*0*/ cond: kotlin.Boolean): kotlin.Boolean
 public fun foo(/*0*/ y: kotlin.Boolean): kotlin.Unit