From 50d5227c5653bd010eed70c923302ca06fe78fcb Mon Sep 17 00:00:00 2001
From: Benoit Daloze <benoit.daloze@oracle.com>
Date: Tue, 10 Oct 2023 11:28:28 +0200
Subject: [PATCH] [GR-49359] Use java.io.Console#isTerminal() on 22+ for
 isatty() checks

---
 .../truffleruby/launcher/RubyLauncher.java    |  4 +-
 .../stdlib/readline/ConsoleHolder.java        |  3 +-
 .../stdlib/readline/IsTTYHelper.java          | 44 +++++++++++++++++++
 3 files changed, 47 insertions(+), 4 deletions(-)
 create mode 100644 src/main/java/org/truffleruby/stdlib/readline/IsTTYHelper.java

diff --git a/src/launcher/java/org/truffleruby/launcher/RubyLauncher.java b/src/launcher/java/org/truffleruby/launcher/RubyLauncher.java
index ebc347795145..71131a1f13e0 100644
--- a/src/launcher/java/org/truffleruby/launcher/RubyLauncher.java
+++ b/src/launcher/java/org/truffleruby/launcher/RubyLauncher.java
@@ -230,7 +230,7 @@ protected boolean parseCommonOption(String defaultOptionPrefix, Map<String, Stri
     @Override
     protected boolean runLauncherAction() {
         String pager;
-        if (helpOptionUsed && System.console() != null && !(pager = getPagerFromEnv()).isEmpty()) {
+        if (helpOptionUsed && isTTY() && !(pager = getPagerFromEnv()).isEmpty()) {
             try {
                 Process process = new ProcessBuilder(pager.split(" "))
                         .redirectOutput(Redirect.INHERIT) // set the output of the pager to the terminal and not a pipe
@@ -264,7 +264,7 @@ private int runRubyMain(Context.Builder contextBuilder, CommandLineOptions confi
                     break;
                 case IRB:
                     config.executionAction = ExecutionAction.PATH;
-                    if (System.console() != null) {
+                    if (isTTY()) {
                         getError().println(
                                 "[ruby] WARNING: truffleruby starts IRB when stdin is a TTY instead of reading from stdin, use '-' to read from stdin");
                         config.executionAction = ExecutionAction.PATH;
diff --git a/src/main/java/org/truffleruby/stdlib/readline/ConsoleHolder.java b/src/main/java/org/truffleruby/stdlib/readline/ConsoleHolder.java
index 436d04a4b3fe..aa644d76907f 100644
--- a/src/main/java/org/truffleruby/stdlib/readline/ConsoleHolder.java
+++ b/src/main/java/org/truffleruby/stdlib/readline/ConsoleHolder.java
@@ -116,8 +116,7 @@ private ConsoleHolder(
         this.in = new IoStream(context, language, inFd, inIo);
         this.out = new IoStream(context, language, outFd, outIo);
 
-        boolean isTTY = System.console() != null;
-        boolean system = isTTY && inFd == 0 && outFd == 1;
+        boolean system = IsTTYHelper.isTTY() && inFd == 0 && outFd == 1;
 
         final Terminal terminal;
         try {
diff --git a/src/main/java/org/truffleruby/stdlib/readline/IsTTYHelper.java b/src/main/java/org/truffleruby/stdlib/readline/IsTTYHelper.java
new file mode 100644
index 000000000000..ab2ab9414be3
--- /dev/null
+++ b/src/main/java/org/truffleruby/stdlib/readline/IsTTYHelper.java
@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2023 Oracle and/or its affiliates. All rights reserved. This
+ * code is released under a tri EPL/GPL/LGPL license. You can use it,
+ * redistribute it and/or modify it under the terms of the:
+ *
+ * Eclipse Public License version 2.0, or
+ * GNU General Public License version 2, or
+ * GNU Lesser General Public License version 2.1.
+ */
+package org.truffleruby.stdlib.readline;
+
+import java.io.Console;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+
+public final class IsTTYHelper {
+
+    private static final Method IS_TERMINAL_METHOD = getIsTerminalMethod();
+
+    private static Method getIsTerminalMethod() {
+        try {
+            return Console.class.getMethod("isTerminal");
+        } catch (NoSuchMethodException e) {
+            return null;
+        }
+    }
+
+    public static boolean isTTY() {
+        Console console = System.console();
+        if (console == null) {
+            return false;
+        }
+        if (IS_TERMINAL_METHOD != null) {
+            try {
+                return (boolean) IS_TERMINAL_METHOD.invoke(console);
+            } catch (IllegalAccessException | InvocationTargetException e) {
+                throw new Error(e);
+            }
+        } else {
+            return true;
+        }
+    }
+
+}