Add FIR tests for header compilation.

^KT-78422

Author: aviroop-123

analysis/low-level-api-fir/tests-gen/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLDiagnosticsFirTestGenerated.java

@@ -0,0 +1,36 @@
+FILE: classDeclaration.kt
+    public final class A : R|kotlin/Any| {
+        public constructor(): R|A| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final fun funA(): R|kotlin/String|
+
+        public final inline fun funB(): R|kotlin/String| {
+            ^funB String(A.funB body)
+        }
+
+        @R|kotlin/OptIn|(markerClass = vararg(<getClass>(Q|kotlin/contracts/ExperimentalContracts|))) public final fun isNotNull(value: R|kotlin/Any?|): R|kotlin/Boolean|
+            [R|Contract description]
+             <
+                Returns(TRUE) -> value != null
+            >
+
+
+        private final fun funC(): R|kotlin/String|
+
+    }
+    public abstract interface B : R|kotlin/Any| {
+        public abstract fun funA(): R|kotlin/String|
+
+        public abstract fun funB(): R|kotlin/String|
+
+    }
+    public final class C : R|B| {
+        public constructor(): R|C| {
+            super<R|kotlin/Any|>()
+        }
+
+        public open override fun funB(): R|kotlin/String|
+
+    }

analysis/low-level-api-fir/tests-gen/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLPartialDiagnosticsFirTestGenerated.java

@@ -0,0 +1,43 @@
+// RUN_PIPELINE_TILL: BACKEND
+// FIR_DUMP
+import kotlin.contracts.ExperimentalContracts
+import kotlin.contracts.contract
+
+class A {
+    fun funA(): String {
+        return "A.funA body"
+    }
+
+    inline fun funB(): String {
+        return "A.funB body"
+    }
+
+    @OptIn(ExperimentalContracts::class)
+    fun isNotNull(value: Any?): Boolean {
+        contract {
+            returns(true) implies (value != null)
+        }
+        return value != null
+    }
+
+    private fun funC(): String {
+        return "A.funC body"
+    }
+}
+
+interface B {
+    fun funA(): String {
+        "B.funA body"
+    }
+
+    fun funB(): String
+}
+
+class C: B {
+    override fun funB(): String {
+        return "C.funB body"
+    }
+}
+
+/* GENERATED_FIR_TAGS: classDeclaration, classReference, contractConditionalEffect, contracts, functionDeclaration,
+inline, interfaceDeclaration, nullableType, override, stringLiteral */

analysis/low-level-api-fir/tests-gen/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLReversedDiagnosticsFirTestGenerated.java

@@ -0,0 +1,12 @@
+FILE: functionDeclaration.kt
+    public final fun funA(): R|kotlin/String|
+    public final inline fun funB(): R|kotlin/String| {
+        ^funB String(funB body)
+    }
+    @R|kotlin/OptIn|(markerClass = vararg(<getClass>(Q|kotlin/contracts/ExperimentalContracts|))) public final fun isNotNull(value: R|kotlin/Any?|): R|kotlin/Boolean|
+        [R|Contract description]
+         <
+            Returns(TRUE) -> value != null
+        >
+
+    private final fun funC(): R|kotlin/String|

compiler/fir/analysis-tests/testData/resolve/headerMode/classDeclaration.fir.txt

@@ -0,0 +1,27 @@
+// RUN_PIPELINE_TILL: BACKEND
+// FIR_DUMP
+import kotlin.contracts.ExperimentalContracts
+import kotlin.contracts.contract
+
+fun funA(): String {
+    return "funA body"
+}
+
+inline fun funB: String {
+    return "funB body"
+}
+
+@OptIn(ExperimentalContracts::class)
+fun isNotNull(value: Any?): Boolean {
+    contract {
+        returns(true) implies (value != null)
+    }
+    return value != null
+}
+
+private fun funC(): String {
+    return "funC body"
+}
+
+/* GENERATED_FIR_TAGS: classReference, contractConditionalEffect, contracts, functionDeclaration, inline, nullableType,
+stringLiteral */

compiler/fir/analysis-tests/testData/resolve/headerMode/classDeclaration.kt

@@ -0,0 +1,22 @@
+FILE: objectDeclaration.kt
+    public final object A : R|kotlin/Any| {
+        private constructor(): R|A| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final fun funA(): R|kotlin/String|
+
+        public final inline fun funB(): R|kotlin/String| {
+            ^funB String(A.funB body)
+        }
+
+        @R|kotlin/OptIn|(markerClass = vararg(<getClass>(Q|kotlin/contracts/ExperimentalContracts|))) public final fun isNotNull(value: R|kotlin/Any?|): R|kotlin/Boolean|
+            [R|Contract description]
+             <
+                Returns(TRUE) -> value != null
+            >
+
+
+        private final fun funC(): R|kotlin/String|
+
+    }

compiler/fir/analysis-tests/testData/resolve/headerMode/functionDeclaration.fir.txt

@@ -0,0 +1,29 @@
+// RUN_PIPELINE_TILL: BACKEND
+// FIR_DUMP
+import kotlin.contracts.ExperimentalContracts
+import kotlin.contracts.contract
+
+object A {
+    fun funA(): String {
+        return "A.funA body"
+    }
+
+    inline fun funB(): String {
+        return "A.funB body"
+    }
+
+    @OptIn(ExperimentalContracts::class)
+    fun isNotNull(value: Any?): Boolean {
+        contract {
+            returns(true) implies (value != null)
+        }
+        return value != null
+    }
+
+    private fun funC(): String {
+        return "A.funC body"
+    }
+}
+
+/* GENERATED_FIR_TAGS: classReference, contractConditionalEffect, contracts, functionDeclaration, inline, nullableType,
+objectDeclaration, stringLiteral */

compiler/fir/analysis-tests/testData/resolve/headerMode/functionDeclaration.kt

@@ -105,6 +105,7 @@ class LanguageVersionSettingsBuilder {
             analysisFlag(AnalysisFlags.dontWarnOnErrorSuppression, trueOrNull(LanguageSettingsDirectives.DONT_WARN_ON_ERROR_SUPPRESSION in directives)),
             analysisFlag(AnalysisFlags.stdlibCompilation, trueOrNull(LanguageSettingsDirectives.STDLIB_COMPILATION in directives)),
             analysisFlag(AnalysisFlags.lenientMode, trueOrNull(LanguageSettingsDirectives.LENIENT_MODE in directives)),
+            analysisFlag(AnalysisFlags.headerMode, trueOrNull(LanguageSettingsDirectives.HEADER_MODE in directives)),
 
             analysisFlag(JvmAnalysisFlags.jvmDefaultMode, directives.singleOrZeroValue(LanguageSettingsDirectives.JVM_DEFAULT_MODE)),
             analysisFlag(JvmAnalysisFlags.inheritMultifileParts, trueOrNull(LanguageSettingsDirectives.INHERIT_MULTIFILE_PARTS in directives)),