fix: emit valid array and string literals in generated java

Author: edengilbertus

amber-pipeline/src/main/kotlin/dev/amber/pipeline/codegen/JavaEmitter.kt

@@ -818,7 +818,7 @@ class JavaEmitter {
 
             "CONST_STRING" -> {
                 val def = renderName(stmt.defs.firstOrNull() ?: return, paramNameMap)
-                builder.addStatement("$def = \$S", stmt.imm?.stringValue ?: "")
+                builder.addStatement("$def = ${javaStringLiteral(stmt.imm?.stringValue ?: "")}")
             }
 
             "CONST_CLASS" -> {
@@ -850,8 +850,7 @@ class JavaEmitter {
                 val def = renderName(stmt.defs.firstOrNull() ?: return, paramNameMap)
                 val typeValue = annotated.emittedDescriptor(stmt.imm?.typeValue ?: return)
                 val sizeArg = renderName(stmt.args.firstOrNull() ?: "0", paramNameMap)
-                val componentDesc = arrayComponentDescriptor(typeValue)
-                builder.addStatement("$def = new \$T[$sizeArg]", descriptorToTypeName(componentDesc))
+                builder.addStatement("$def = ${newArrayExpression(typeValue, sizeArg, annotated.renameIndex)}")
             }
 
             "INVOKE" -> {
@@ -1106,6 +1105,45 @@ class JavaEmitter {
     private fun arrayComponentDescriptor(descriptor: String): String =
         if (descriptor.startsWith("[")) descriptor.substring(1) else descriptor
 
+    private fun newArrayExpression(descriptor: String, sizeArg: String, renameIndex: dev.amber.pipeline.mapping.MappingRenameIndex): String {
+        var dimensions = 0
+        var component = descriptor
+        while (component.startsWith("[")) {
+            dimensions += 1
+            component = component.substring(1)
+        }
+        val componentType = descriptorToTypeName(component, renameIndex).toString()
+        val trailing = if (dimensions <= 1) "" else List(dimensions - 1) { "[]" }.joinToString("")
+        return "new $componentType[$sizeArg]$trailing"
+    }
+
+    private fun javaStringLiteral(value: String): String {
+        val escaped = buildString {
+            append('"')
+            value.forEach { ch ->
+                when (ch) {
+                    '\\' -> append("\\\\")
+                    '"' -> append("\\\"")
+                    '\n' -> append("\\n")
+                    '\r' -> append("\\r")
+                    '\t' -> append("\\t")
+                    '\b' -> append("\\b")
+                    '\u000C' -> append("\\f")
+                    else -> {
+                        if (ch.code < 0x20 || ch == '\u0085' || ch == '\u2028' || ch == '\u2029') {
+                            append("\\u")
+                            append(ch.code.toString(16).padStart(4, '0'))
+                        } else {
+                            append(ch)
+                        }
+                    }
+                }
+            }
+            append('"')
+        }
+        return escaped
+    }
+
     private fun safeClassName(dotName: String): ClassName {
         val lastDot = dotName.lastIndexOf('.')
         val packagePart = if (lastDot >= 0) sanitizePackageName(dotName.substring(0, lastDot)) else ""