From 6c41ded544558d01e87d20000360c682a88303b1 Mon Sep 17 00:00:00 2001
From: Urban Müller
Date: Thu, 3 Aug 2023 17:55:27 +0200
Subject: allow echoing and dry-running of it::exec/it::system commands

---
 it.class    | 28 ++++++++++++++++------------
 test/exec.t | 16 +++++++++-------
 2 files changed, 25 insertions(+), 19 deletions(-)

diff --git a/it.class b/it.class
index a788de3..858bbe4 100644
--- a/it.class
+++ b/it.class
@@ -354,7 +354,7 @@ static function error($p = array(), $extra = null)
  */
 static function fatal($p)
 {
-	it::error(['fatal' => true, 'backtraceskip' => 2] + (array)$p);
+	it::error(['fatal' => true, 'backtraceskip' => 1] + (array)$p);
 }
 
 
@@ -672,19 +672,23 @@ static function filter_keys($array, $keys, $p = array())
 
 /**
  * Construct shell command using it::shell_command, log it, execute it and return output as string.
- * {keyword} quotes and inserts value from assoc array like ET()
- * {0} .. {n} quotes and inserts positional arguments
- * {-opts} array of opts => {value,true,false,null}: it::exec('ls {-opts}', ['-opts' => ["-l" => true]]);
+ * @param $cmd shell command to be executed. String may contain:
+ *   {keyword} quotes and inserts value from assoc array like ET()
+ *   {0} .. {n} quotes and inserts positional arguments
+ *   {-opts} array of opts => {value,true,false,null}: it::exec('ls {-opts}', ['-opts' => ["-l" => true]]);
  * @param $cmd Format string with {keywords} a la ET()
  * @param $args varargs, contains key => val arrays or positionals for filling in cmd line. val=null expands to nothing
+ *   'callback' optional closure, $fn($cmd) => print($cmd) for echo, => !print($cmd) for echo and suppress
  * @return output of command. shell errors not detectable, consider it::system or see  /www/server/log/error_log
  */
 static function exec($cmd, ...$args)
 {
-	$cmd = it::shell_command($cmd, ...$args); # NOPHPLINT
-
+	$args = array_reduce($args, fn($carry, $v) => array_merge($carry, (array)$v), []); # varargs to single array
+	$cmd = it::shell_command($cmd, $args); # NOPHPLINT
 	$before = gettimeofday(true);
-	$result = EDC('noexec') ? "" : (string)shell_exec("set +o posix\n" . $cmd);
+
+	if ((!($args['callback'] instanceof Closure) || $args['callback']($cmd)) && !EDC('noexec'))
+		$result = (string)shell_exec("set +o posix\n" . $cmd);
 
 	@it::log('exec', round((gettimeofday(true) - $before)*1000) . "\t$cmd");
 
@@ -699,13 +703,13 @@ static function exec($cmd, ...$args)
  */
 static function system($cmd, ...$args)
 {
-	$cmd = it::shell_command($cmd, ...$args); # NOPHPLINT
-
+	$args = array_reduce($args, fn($carry, $v) => array_merge($carry, (array)$v), []); # varargs to single array
+	$cmd = it::shell_command($cmd, $args); # NOPHPLINT
 	$before = gettimeofday(true);
-	if (!EDC('noexec'))
+	$result = 0;
+
+	if ((!($args['callback'] instanceof Closure) || $args['callback']($cmd)) && !EDC('noexec'))
 		system("set +o posix\n" . $cmd, $result);
-	else
-		$result = 0;
 
 	@it::log('exec', round((gettimeofday(true) - $before)*1000) . "\t$cmd");
 
diff --git a/test/exec.t b/test/exec.t
index 5f3ebb5..9e55726 100755
--- a/test/exec.t
+++ b/test/exec.t
@@ -4,14 +4,16 @@
 # Tests for getopt in it.class
 
 is(it::exec("echo gna"), "gna\n", "basic exec");
-is(it::exec("echo {arg}", ['arg' => 'gna']), "gna\n", "exec with argument");
+is(it::exec("echo {arg}", ['arg' => 'gnu'], ['arg' => "gna"]), "gna\n", "exec with argument");
 is(it::exec("echo {0}", 'gna'), "gna\n", "exec with positional argument");
-is(it::shell_command("echo {arg}", ['arg' => 'gna07,-:blah']), "echo gna07,-:blah", "don't quote arguments with only whitelistes characters");
-is(it::shell_command("echo {arg}", ['arg' => '2>&1']), "echo '2>&1'", "quote arguments with dangerous characters");
-is(it::shell_command("echo {arg}", ['arg' => '']), "echo ''", "quote empty arguments");
-is(it::shell_command("echo {arg}", ['arg' => null]), "echo ", "remove null values");
-is(it::shell_command("echo {arg}", ['arg' => false]), "echo ", "remove false values");
-is(it::shell_command("echo {arg}", ['arg' => []]), "echo ", "remove empty arrays");
+is(it::shell_command("echo {arg}", ['arg' => 'gna07,-:blah']),  "echo gna07,-:blah", "don't quote arguments with only whitelistes characters");
+is(it::shell_command("echo {arg}", ['arg' => '2>&1']),          "echo '2>&1'", "quote arguments with dangerous characters");
+is(it::shell_command("echo {arg}", ['arg' => '']),              "echo ''", "quote empty arguments");
+is(it::shell_command("echo {arg}", ['arg' => null]),            "echo ", "remove null values");
+is(it::shell_command("echo {arg}", ['arg' => false]),           "echo ", "remove false values");
+is(it::shell_command("echo {arg}", ['arg' => []]),              "echo ", "remove empty arrays");
+is(it::shell_command("echo {arg}", (object)['arg' => "foo"])  , "echo foo", "allow objects");
+is(it::shell_command("echo {arg}", ['arg' => 1], ['arg' => 2]), "echo 2", "support varargs");
 
 
 is(
-- 
cgit v1.2.3