From 8c159dd5bcfb985090f76573e38f659fa265b2af Mon Sep 17 00:00:00 2001
From: Timothy J Warren <tim@timshomepage.net>
Date: Thu, 5 Dec 2019 11:00:03 -0500
Subject: [PATCH] Attempt to verify tput exists before using it

---
 src/functions.php | 25 +++++++++++++++++++++----
 1 file changed, 21 insertions(+), 4 deletions(-)

diff --git a/src/functions.php b/src/functions.php
index c012a62..771c7a7 100644
--- a/src/functions.php
+++ b/src/functions.php
@@ -10,6 +10,17 @@ use Aviat\Kilo\Enum\{
 	Highlight,
 };
 
+/**
+ * See if tput exists for fallback terminal size detection
+ *
+ * @return bool
+ * @codeCoverageIgnore
+ */
+function has_tput(): bool
+{
+	return shell_exec('type tput') === 0;
+}
+
 // ----------------------------------------------------------------------------
 // ! Terminal size
 // ----------------------------------------------------------------------------
@@ -29,10 +40,16 @@ function get_window_size(): array
 
 	if ($res === -1 || $ws->ws_col === 0)
 	{
-		$rows = trim(shell_exec('tput lines'));
-		$cols = trim(shell_exec('tput cols'));
+		if (has_tput())
+		{
+			$rows = trim(shell_exec('tput lines'));
+			$cols = trim(shell_exec('tput cols'));
 
-		return [(int)$rows, (int)$cols];
+			return [(int)$rows, (int)$cols];
+		}
+
+		// Worst-case, return an arbitrary 'standard' size
+		return [80, 25];
 	}
 
 	return [$ws->ws_row, $ws->ws_col];
@@ -110,7 +127,7 @@ function is_digit(string $char): bool
  */
 function is_space(string $char): bool
 {
-	$ws = [' ', "\t", "\n", "\r", "\xa", "\xb", "\xc"];
+	$ws = [' ', "\t", "\n", "\r", "\v", "\f"];
 	return is_ascii($char) && in_array($char, $ws, TRUE);
 }