From 80933c287d228ee46a580bd70033b9b4d838057b Mon Sep 17 00:00:00 2001
From: sergeych <real.sergeych@gmail.com>
Date: Mon, 12 Jan 2026 16:15:19 +0100
Subject: [PATCH] Refactor nullable suffix handling in compiler (nullable
 declaration bug fixed)

---
 .../kotlin/net/sergeych/lyng/Compiler.kt      |  7 +++++-
 .../net/sergeych/lyng/CompilerContext.kt      | 23 +++++++++++++------
 lynglib/src/commonTest/kotlin/ScriptTest.kt   |  2 +-
 3 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/lynglib/src/commonMain/kotlin/net/sergeych/lyng/Compiler.kt b/lynglib/src/commonMain/kotlin/net/sergeych/lyng/Compiler.kt
index ad93c31..e7ac460 100644
--- a/lynglib/src/commonMain/kotlin/net/sergeych/lyng/Compiler.kt
+++ b/lynglib/src/commonMain/kotlin/net/sergeych/lyng/Compiler.kt
@@ -1048,7 +1048,12 @@ class Compiler(
         }
 
         // Nullable suffix after base or generic
-        val isNullable = cc.skipTokenOfType(Token.Type.QUESTION, isOptional = true)
+        val isNullable = if (cc.skipTokenOfType(Token.Type.QUESTION, isOptional = true)) {
+            true
+        } else if (cc.skipTokenOfType(Token.Type.IFNULLASSIGN, isOptional = true)) {
+            cc.pushPendingAssign()
+            true
+        } else false
         val endPos = cc.currentPos()
 
         val miniRef = buildBaseRef(if (miniArgs != null) endPos else lastEnd, miniArgs, isNullable)
diff --git a/lynglib/src/commonMain/kotlin/net/sergeych/lyng/CompilerContext.kt b/lynglib/src/commonMain/kotlin/net/sergeych/lyng/CompilerContext.kt
index 4f4b350..c0ce639 100644
--- a/lynglib/src/commonMain/kotlin/net/sergeych/lyng/CompilerContext.kt
+++ b/lynglib/src/commonMain/kotlin/net/sergeych/lyng/CompilerContext.kt
@@ -35,8 +35,9 @@ class CompilerContext(val tokens: List<Token>) {
 
     var currentIndex = 0
     private var pendingGT = 0
+    private var pendingAssign = false
 
-    fun hasNext() = currentIndex < tokens.size || pendingGT > 0
+    fun hasNext() = currentIndex < tokens.size || pendingGT > 0 || pendingAssign
     fun hasPrevious() = currentIndex > 0
     fun next(): Token {
         if (pendingGT > 0) {
@@ -44,6 +45,11 @@ class CompilerContext(val tokens: List<Token>) {
             val last = tokens[currentIndex - 1]
             return Token(">", last.pos.copy(column = last.pos.column + 1), Token.Type.GT)
         }
+        if (pendingAssign) {
+            pendingAssign = false
+            val last = tokens[currentIndex - 1]
+            return Token("=", last.pos.copy(column = last.pos.column + 1), Token.Type.ASSIGN)
+        }
         return if (currentIndex < tokens.size) tokens[currentIndex++]
         else Token("", tokens.last().pos, Token.Type.EOF)
     }
@@ -52,16 +58,19 @@ class CompilerContext(val tokens: List<Token>) {
         pendingGT++
     }
 
-    fun previous() = if (pendingGT > 0) {
-        pendingGT-- // This is wrong, previous should go back. 
-        // But we don't really use previous() in generics parser after splitting.
-        throw IllegalStateException("previous() not supported after pushPendingGT")
+    fun pushPendingAssign() {
+        pendingAssign = true
+    }
+
+    fun previous() = if (pendingGT > 0 || pendingAssign) {
+        throw IllegalStateException("previous() not supported after pushPending tokens")
     } else if (!hasPrevious()) throw IllegalStateException("No previous token") else tokens[--currentIndex]
 
-    fun savePos() = (currentIndex shl 2) or (pendingGT and 3)
+    fun savePos() = (currentIndex shl 3) or (pendingGT and 3) or (if (pendingAssign) 4 else 0)
     fun restorePos(pos: Int) {
-        currentIndex = pos shr 2
+        currentIndex = pos shr 3
         pendingGT = pos and 3
+        pendingAssign = (pos and 4) != 0
     }
 
     fun ensureLabelIsValid(pos: Pos, label: String) {
diff --git a/lynglib/src/commonTest/kotlin/ScriptTest.kt b/lynglib/src/commonTest/kotlin/ScriptTest.kt
index 5728223..34a71ca 100644
--- a/lynglib/src/commonTest/kotlin/ScriptTest.kt
+++ b/lynglib/src/commonTest/kotlin/ScriptTest.kt
@@ -4803,7 +4803,7 @@ class ScriptTest {
             fun f(a: String = "foo") = a + "!"
             fun g(a: String? = null) = a ?: "!!"
             assertEquals(f(), "foo!")
-            assertEquals(f(), "!!")
+            assertEquals(g(), "!!")
             assertEquals(f("bar"), "bar!")
             class T(b: Int=42,c: String?=null) 
             assertEquals(42, T().b)