added return statement support

2026-01-06 02:18:31 +01:00
1 parent 5fc0969491
commit d91acd593a
@@ -0,0 +1,128 @@
+import kotlinx.coroutines.test.runTest
+import net.sergeych.lyng.ScriptError
+import net.sergeych.lyng.eval
+import net.sergeych.lyng.obj.toInt
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFailsWith
+
+class ReturnStatementTest {
+
+    @Test
+    fun testBasicReturn() = runTest {
+        assertEquals(10, eval("""
+            fun foo() {
+                return 10
+                20
+            }
+            foo()
+        """).toInt())
+    }
+
+    @Test
+    fun testReturnFromIf() = runTest {
+        assertEquals(5, eval("""
+            fun foo(x) {
+                if (x > 0) return 5
+                10
+            }
+            foo(1)
+        """).toInt())
+        
+        assertEquals(10, eval("""
+            fun foo(x) {
+                if (x > 0) return 5
+                10
+            }
+            foo(-1)
+        """).toInt())
+    }
+
+    @Test
+    fun testReturnFromLambda() = runTest {
+        assertEquals(2, eval("""
+            val f = { x ->
+                if (x < 0) return 0
+                x * 2
+            }
+            f(1)
+        """).toInt())
+        
+        assertEquals(0, eval("""
+            val f = { x ->
+                if (x < 0) return 0
+                x * 2
+            }
+            f(-1)
+        """).toInt())
+    }
+
+    @Test
+    fun testNonLocalReturn() = runTest {
+        assertEquals(100, eval("""
+            fun outer() {
+                [1, 2, 3].forEach {
+                    if (it == 2) return@outer 100
+                }
+                0
+            }
+            outer()
+        """).toInt())
+    }
+
+    @Test
+    fun testLabeledLambdaReturn() = runTest {
+        assertEquals(42, eval("""
+            val f = @inner { x ->
+                if (x == 0) return@inner 42
+                x
+            }
+            f(0)
+        """).toInt())
+        
+        assertEquals(5, eval("""
+            val f = @inner { x ->
+                if (x == 0) return@inner 42
+                x
+            }
+            f(5)
+        """).toInt())
+    }
+
+    @Test
+    fun testForbidEqualReturn() = runTest {
+        assertFailsWith<ScriptError> {
+            eval("fun foo(x) = return x")
+        }
+    }
+
+    @Test
+    fun testDeepNestedReturn() = runTest {
+        assertEquals(42, eval("""
+            fun find() {
+                val data = [[1, 2], [3, 42], [5, 6]]
+                data.forEach { row ->
+                    row.forEach { item ->
+                        if (item == 42) return@find item
+                    }
+                }
+                0
+            }
+            find()
+        """).toInt())
+    }
+
+    @Test
+    fun testReturnFromOuterLambda() = runTest {
+        assertEquals("found", eval("""
+            val f_outer = @outer {
+                val f_inner = {
+                    return@outer "found"
+                }
+                f_inner()
+                "not found"
+            }
+            f_outer()
+        """).toString())
+    }
+}