From 77d6cc203c7dfd564ad127ace8925ac4a0d2d2e0 Mon Sep 17 00:00:00 2001
From: Aaro Koivukangas <aaro.koivukangas@gmail.com>
Date: Sat, 28 Feb 2026 15:06:56 +0200
Subject: [PATCH] Implement equals

---
 compiler/src/main/scala/Parser.scala      | 16 +++++++++++
 compiler/src/test/scala/ParserTests.scala | 34 +++++++++++++++++++++++
 2 files changed, 50 insertions(+)

diff --git a/compiler/src/main/scala/Parser.scala b/compiler/src/main/scala/Parser.scala
index 1a2fe12..6b7af71 100644
--- a/compiler/src/main/scala/Parser.scala
+++ b/compiler/src/main/scala/Parser.scala
@@ -145,6 +145,21 @@ class Parser(tokens: List[Token]):
     return Function(fnName, args)
 
 
+  def parseEquals(parsedEqualsLeft: Option[Expression], initialDepth: Int = 0): Expression =
+    var depth = initialDepth
+    val left = parsedEqualsLeft.getOrElse(parseFactor())
+    consume(Some("=")).get
+    var right = BinaryOperator(left, "=", parseExpression())
+
+    while
+      peek().value == "="
+    do
+      consume(Some("=")).get
+      right = BinaryOperator(left, "=", right)
+    
+    return right
+
+
   def parseExpression(initialDepth: Int = 0): Expression =
     var depth = initialDepth
     var left = parseFactor()
@@ -152,6 +167,7 @@ class Parser(tokens: List[Token]):
     // If identifier is followed by ( => it is a function call (or syntax error :D)
     left = left match {
       case left: Identifier if peek().value == "(" => parseFunction(Some(left.name))
+      case left if peek().value == "=" => parseEquals(Some(left))
       case _ => left
     }
     
diff --git a/compiler/src/test/scala/ParserTests.scala b/compiler/src/test/scala/ParserTests.scala
index 9ff4099..0abc06c 100644
--- a/compiler/src/test/scala/ParserTests.scala
+++ b/compiler/src/test/scala/ParserTests.scala
@@ -498,4 +498,38 @@ class ParserTests extends munit.FunSuite {
 
     assertEquals(result, expected)
   }
+
+  test("should parse simple assignment") {
+    val p = testParser("a = b")
+    val result = p.parseExpression()
+    val expected = BinaryOperator(Identifier("a"), "=", Identifier("b"))
+
+    assertEquals(result, expected)
+  }
+  test("should parse simple triple assignment right-associatively") {
+    val p = testParser("a = b = c")
+    val result = p.parseExpression()
+    val expected = BinaryOperator(
+      Identifier("a"),
+      "=",
+      BinaryOperator(Identifier("b"), "=", Identifier("c"))
+    )
+
+    assertEquals(result, expected)
+  }
+  test("should parse triple assignment with expressions right-associatively") {
+    val p = testParser("a = b = 1+print_bool(not true)")
+    val result = p.parseExpression()
+    val expected = BinaryOperator(
+      Identifier("a"),
+      "=",
+      BinaryOperator(
+        Identifier("b"),
+        "=",
+        BinaryOperator(Literal(1), "+", Function("print_bool", List(UnaryOperator("not", Identifier("true")))))
+      )
+    )
+
+    assertEquals(result, expected)
+  }
 }