test: Add generated tests for eu.jameshamilton.klox.compile.Compiler.FunctionCompiler

- compile
- compile
- visitAssignExpr
- create

Author: mrjameshamilton

src/test/kotlin/eu/jameshamilton/klox/compile/CompilerFunctionCompilerTest.kt

@@ -0,0 +1,54 @@
+package eu.jameshamilton.klox.compile
+
+import eu.jameshamilton.klox.compile
+import eu.jameshamilton.klox.execute
+import eu.jameshamilton.klox.run
+import io.kotest.core.spec.style.FunSpec
+import java.io.File
+
+class CompilerFunctionCompilerTest : FunSpec({
+    test("deeply nested closure captures variable from grandparent scope") {
+        val loxSource = """
+            fun outer() {
+                var x = 42;
+                fun middle() {
+                    fun inner() {
+                        print x;
+                    }
+                    inner();
+                }
+                middle();
+            }
+            outer(); // expect: 42
+        """.trimIndent()
+
+        val tempFile = File.createTempFile("nested_closure", ".lox")
+        tempFile.deleteOnExit()
+        tempFile.writeText(loxSource)
+
+        execute(tempFile) { compile(tempFile)?.let { run(it) } }
+    }
+
+    test("deeply nested closure captures and modifies variable from grandparent scope") {
+        val loxSource = """
+            fun outer() {
+                var x = 1;
+                fun middle() {
+                    fun inner() {
+                        x = x + 10;
+                    }
+                    inner();
+                }
+                middle();
+                print x; // expect: 11
+            }
+            outer();
+        """.trimIndent()
+
+        val tempFile = File.createTempFile("nested_closure_modify", ".lox")
+        tempFile.deleteOnExit()
+        tempFile.writeText(loxSource)
+
+        execute(tempFile) { compile(tempFile)?.let { run(it) } }
+    }
+})