+ String.replace

lynglib/src/commonTest/kotlin/ScriptTest.kt

@@ -4160,6 +4160,30 @@ class ScriptTest {
         )
     }
 
+    @Test
+    fun testStringReplaceVariants() = runTest {
+        eval(
+            """
+            assertEquals("bonono", "banana".replace('a', 'o'))
+            assertEquals("bxnxnx", "banana".replace('a', "x"))
+            assertEquals("a-b-c", "a.b.c".replace(".", "-"))
+            assertEquals("bonana", "banana".replaceFirst('a', 'o'))
+            assertEquals("bxnana", "banana".replaceFirst('a', "x"))
+            assertEquals("a-b.c", "a.b.c".replaceFirst(".", "-"))
+
+            assertEquals("foo-#-bar-#", "foo-42-bar-17".replace("\d+".re, "#"))
+            assertEquals("foo-[42]-bar-[17]", "foo-42-bar-17".replace("(\d+)".re) { m ->
+                "[" + m[1] + "]"
+            })
+            assertEquals("foo-[42]-bar-17", "foo-42-bar-17".replaceFirst("(\d+)".re) { m ->
+                "[" + m[1] + "]"
+            })
+            assertEquals("YEAR-04-08", "2026-04-08".replaceFirst("\d+".re, "YEAR"))
+            """
+                .trimIndent()
+        )
+    }
+
     @Test
     fun extensionsMustBeLocalPerScope() = runTest {
         val scope1 = Script.newScope()

lynglib/src/commonTest/kotlin/net/sergeych/lyng/tools/LyngLanguageToolsTest.kt

@@ -102,6 +102,27 @@ class LyngLanguageToolsTest {
         assertTrue(local.typeText?.contains("String") == true, "Expected type for local, got ${local.typeText}")
     }
 
+    @Test
+    fun languageTools_docs_for_builtin_string_replace() = runTest {
+        val code = """
+            val s = "a.b.c".replace(".", "-")
+        """.trimIndent()
+        val res = LyngLanguageTools.analyze(code, "replace_docs.lyng")
+        val replaceOffset = code.indexOf("replace")
+        val doc = LyngLanguageTools.docAt(res, replaceOffset)
+        assertNotNull(doc, "Docs should resolve for built-in String.replace")
+        assertEquals("replace", doc.target.name)
+        assertEquals("String", doc.target.containerName)
+        assertTrue(
+            doc.signature?.startsWith("fun String.replace(") == true,
+            "Expected String.replace signature, got ${doc.signature}"
+        )
+        assertTrue(
+            doc.doc?.summary?.contains("string with all literal or regex matches replaced") == true,
+            "Expected replace summary, got ${doc.doc?.summary}"
+        )
+    }
+
     @Test
     fun languageTools_definition_and_usages() = runTest {
         val code = """