Passing the separator after the array is no longer supported

.gitattributes

@@ -0,0 +1,2 @@
+# Force LF
+* text eol=lf

.php-commitizen.php

@@ -0,0 +1,41 @@
+<?php
+
+declare(strict_types=1);
+
+return [
+    'type' => [
+        'lengthMin' => 3,
+        'lengthMax' => 8,
+        'acceptExtra' => false,
+        'values' => [
+            'feat',
+            'fix',
+            'docs',
+            'chore',
+            'test',
+            'refactor',
+            'revert',
+            'ci',
+        ]
+    ],
+    'scope' => [
+        'lengthMin' => 0,
+        'lengthMax' => 10,
+        'acceptExtra' => true,
+        'values' => [],
+    ],
+    'description' => [
+        'lengthMin' => 1,
+        'lengthMax' => 47,
+    ],
+    'subject' => [
+        'lengthMin' => 1,
+        'lengthMax' => 69,
+    ],
+    'body' => [
+        'wrap' => 72,
+    ],
+    'footer' => [
+        'wrap' => 72,
+    ],
+];

.php-cs-fixer.dist.php

@@ -0,0 +1,59 @@
+<?php
+
+declare(strict_types=1);
+
+$header = <<<EOF
+This file is part of the "PHP Helpers: Command-line Functions" repository.
+
+Copyright 2019-2021 Alannah Kearney <hi@alannahkearney.com>
+
+For the full copyright and license information, please view the LICENCE
+file that was distributed with this source code.
+EOF;
+
+return (new PhpCsFixer\Config())
+    ->setUsingCache(true)
+    ->setRiskyAllowed(true)
+    ->setFinder(
+        (new PhpCsFixer\Finder())
+            ->files()
+            ->name('*.php')
+            ->in(__DIR__)
+            ->exclude(__DIR__.'/vendor')
+    )
+    ->setRules([
+        '@PSR2' => true,
+        '@Symfony' => true,
+        'is_null' => true,
+        'blank_line_before_statement' => ['statements' => ['continue', 'declare', 'return', 'throw', 'try']],
+        'cast_spaces' => ['space' => 'single'],
+        'header_comment' => ['header' => $header],
+        'include' => true,
+        'class_attributes_separation' => ['elements' => ['const' => 'one', 'method' => 'one', 'property' => 'one']],
+        'no_blank_lines_after_class_opening' => true,
+        'no_blank_lines_after_phpdoc' => true,
+        'no_empty_statement' => true,
+        'no_extra_blank_lines' => true,
+        'no_leading_import_slash' => true,
+        'no_leading_namespace_whitespace' => true,
+        'no_trailing_comma_in_singleline_array' => true,
+        'no_unused_imports' => true,
+        'no_whitespace_in_blank_line' => true,
+        'object_operator_without_whitespace' => true,
+        'phpdoc_align' => true,
+        'phpdoc_indent' => true,
+        'phpdoc_no_access' => true,
+        'phpdoc_no_package' => true,
+        'phpdoc_order' => true,
+        'phpdoc_scalar' => true,
+        'phpdoc_trim' => true,
+        'phpdoc_types' => true,
+        'psr_autoloading' => true,
+        'array_syntax' => ['syntax' => 'short'],
+        'declare_strict_types' => true,
+        'single_blank_line_before_namespace' => true,
+        'standardize_not_equals' => true,
+        'ternary_operator_spaces' => true,
+        'trailing_comma_in_multiline' => true,
+    ])
+;

CHANGELOG.md

@@ -3,15 +3,47 @@
 All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](http://semver.org/).
 
-**View all [Unreleased][] changes here**
+## [1.1.10][]
+#### Added
+-   Added `which()` function
+
+#### Changed
+-   Refactor of `run_command()` function to return an exit code
+
+## [1.1.9][]
+#### Added
+-   Added `run_command()` function
+-   Added `RunCommandFailedException` exception
+-   Added `pointybeard/helpers-exceptions-readabletrace` package
+
+## [1.1.8][]
+#### Changed
+-   Updated `manpage()` to work with `pointybeard/helpers-cli-input` 1.2
+-   Using v1.2.x of `pointybeard/helpers-cli-input`
+-   Updated version constraints in `composer.json`
+
+## [1.1.7][]
+#### Added
+-   Added `pointybeard/helpers-functions-debug` package
+
+#### Changed
+-   Using `readable_debug_backtrace()` (provided by `pointybeard/helpers-functions-debug`) in `display_error_and_exit()` to produce a trace if one is provided
+
+## [1.1.6][]
+#### Added
+-   Added `display_error_and_exit` function
+
+## [1.1.5][]
+#### Changed
+-   Updated to work with `pointybeard/helpers-cli-input` v1.1.x
 
 ## [1.1.4][]
 #### Changed
--   Refactoring of `manpage()` to hide 'Options' and/or 'Arguments' if there are none to show.
+-   Refactoring of `manpage()` to hide 'Options' and/or 'Arguments' if there are none to show
 
 ## [1.1.3][]
 #### Changed
--   Updated `manpage()` to include `foregroundColour`, `headingColour`, and `additional` arguments. Removed `example` argument in favour of including it inside `additional`.
+-   Updated `manpage()` to include `foregroundColour`, `headingColour`, and `additional` arguments. Removed `example` argument in favour of including it inside `additional`
 -   Added `pointybeard/helpers-cli-colour` composer package
 
 ## [1.1.2][]
@@ -34,7 +66,11 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 #### Added
 -   Initial release
 
-[Unreleased]: https://github.com/pointybeard/helpers-functions-cli/compare/1.1.4...integration
+[1.1.9]: https://github.com/pointybeard/helpers-functions-cli/compare/1.1.8...1.1.9
+[1.1.8]: https://github.com/pointybeard/helpers-functions-cli/compare/1.1.7...1.1.8
+[1.1.7]: https://github.com/pointybeard/helpers-functions-cli/compare/1.1.6...1.1.7
+[1.1.6]: https://github.com/pointybeard/helpers-functions-cli/compare/1.1.5...1.1.6
+[1.1.5]: https://github.com/pointybeard/helpers-functions-cli/compare/1.1.4...1.1.5
 [1.1.4]: https://github.com/pointybeard/helpers-functions-cli/compare/1.1.3...1.1.4
 [1.1.3]: https://github.com/pointybeard/helpers-functions-cli/compare/1.1.2...1.1.3
 [1.1.2]: https://github.com/pointybeard/helpers-functions-cli/compare/1.1.1...1.1.2

LICENCE

@@ -3,7 +3,7 @@ unless otherwise specified, released under the MIT licence as follows:
 
 ----- begin license block -----
 
-Copyright 2019 Alannah Kearney
+Copyright 2019-2021 Alannah Kearney
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -1,7 +1,7 @@
 # PHP Helpers: Command-line Functions
 
--   Version: v1.1.4
--   Date: May 24 2019
+-   Version: v1.1.10
+-   Date: July 29 2021
 -   [Release notes](https://github.com/pointybeard/helpers-functions-cli/blob/master/CHANGELOG.md)
 -   [GitHub repository](https://github.com/pointybeard/helpers-functions-cli)
 
@@ -28,11 +28,15 @@ This library is a collection convenience function for command-line tasks. They a
 
 The following functions are provided:
 
--   `can_invoke_bash() : bool`
--   `is_su() : bool`
--   `usage(string $name, Cli\Input\InputCollection $collection) : string`
--   `manpage(string $name, string $version, string $description, Input\InputCollection $collection, $foregroundColour=Colour\Colour::FG_DEFAULT, $headingColour=Colour\Colour::FG_WHITE, array $additional=[]): string`
--   `get_window_size(): array`
+-   `run_command()`
+-   `which()`
+-   `can_invoke_bash()`
+-   `is_su()`
+-   `run_command()`
+-   `usage()`
+-   `manpage()`
+-   `get_window_size()`
+-   `display_error_and_exit()`
 
 Example usage:
 
@@ -46,6 +50,9 @@ use pointybeard\Helpers\Cli\Input;
 use pointybeard\Helpers\Cli\Colour\Colour;
 use pointybeard\Helpers\Functions\Cli;
 
+var_dump(Cli\which("ls"));
+// string(11) "/usr/bin/ls"
+
 var_dump(Cli\can_invoke_bash());
 // bool(true)
 
@@ -58,59 +65,89 @@ var_dump(Cli\get_window_size());
 //   'lines' => string(2) "68"
 // }
 
+Cli\run_command("date", $out);
+var_dump($out);
+// string(29) "Mon  6 Apr 17:20:29 AEST 2020"
+
+try{
+    Cli\run_command("not -a --command", $out, $err);
+} catch(Cli\Exceptions\RunCommandFailedException $ex) {
+    var_dump($ex->getMessage(), $ex->getCommand(), $ex->getError());
+}
+// string(54) "Failed to run command. Returned: sh: 1: not: not found"
+// string(16) "not -a --command"
+// string(21) "sh: 1: not: not found"
+
 echo Cli\manpage(
     'test',
-    '1.0.0',
+    '1.0.2',
     'A simple test command with a really long description. This is an intentionally very long argument description so we can check that word wrapping is working correctly. It should wrap to the window',
     (new Input\InputCollection())
-        ->append(new Input\Types\Argument(
-            'action',
-            Input\AbstractInputType::FLAG_REQUIRED,
-            'The name of the action to perform. This is an intentionally very long argument description so we can check that word wrapping is working correctly'
-        ))
-        ->append(new Input\Types\Option(
-            'v',
-            null,
-            Input\AbstractInputType::FLAG_OPTIONAL | Input\AbstractInputType::FLAG_TYPE_INCREMENTING,
-            'verbosity level. -v (errors only), -vv (warnings and errors), -vvv (everything).',
-            null,
-            0
-        ))
-        ->append(new Input\Types\Option(
-            'd',
-            'data',
-            Input\AbstractInputType::FLAG_OPTIONAL | Input\AbstractInputType::FLAG_VALUE_REQUIRED,
-            'Path to the input JSON data.'
-        )),
+        ->add(
+            Input\InputTypeFactory::build('Argument')
+                ->name('action')
+                ->flags(Input\AbstractInputType::FLAG_REQUIRED)
+                ->description('The name of the action to perform. This is an intentionally very long argument description so we can check that word wrapping is working correctly')
+        )
+        ->add(
+            Input\InputTypeFactory::build('IncrementingFlag')
+                ->name('v')
+                ->flags(Input\AbstractInputType::FLAG_OPTIONAL | Input\AbstractInputType::FLAG_TYPE_INCREMENTING)
+                ->description('verbosity level. -v (errors only), -vv (warnings and errors), -vvv (everything).')
+                ->validator(new Input\Validator(
+                    function (Input\AbstractInputType $input, Input\AbstractInputHandler $context) {
+                        // Make sure verbosity level never goes above 3
+                        return min(3, (int) $context->find('v'));
+                    }
+                ))
+        )
+        ->add(
+            Input\InputTypeFactory::build('Option')
+                ->name('P')
+                ->flags(Input\AbstractInputType::FLAG_OPTIONAL | Input\AbstractInputType::FLAG_VALUE_OPTIONAL)
+                ->description('Port to use for all connections.')
+                ->default('3306')
+        )
+        ->add(
+            Input\InputTypeFactory::build('LongOption')
+                ->name('data')
+                ->short('d')
+                ->flags(Input\AbstractInputType::FLAG_OPTIONAL | Input\AbstractInputType::FLAG_VALUE_REQUIRED)
+                ->description('Path to the input JSON data.')
+        ),
     Colour::FG_GREEN,
     Colour::FG_WHITE,
     [
-        'Examples' => 'php -f test.php -- import -vvv -d test.json'
+        'Examples' => 'php -f test.php -- import -vvv -d test.json',
     ]
 ).PHP_EOL;
 
-// test 1.0.0, A simple test command with a really long description. This is an intentionally very long argument description so we can check that word wrapping is working correctly. It should wrap to the window
+// test 1.0.2, A simple test command with a really long description. This is an intentionally very long argument description so we can check that word wrapping is working correctly. It should wrap to the window
 // Usage: test [OPTIONS]... ACTION...
 //
 // Arguments:
-// ACTION              The name of the action to perform. This is an
-//                     intentionally very long argument description so we can check
-//                     that word wrapping is working correctly
+// ACTION              The name of the action to perform. This is an intentionally very
+//                     long argument description so we can check that word wrapping is
+//                     working correctly
 //
 // Options:
-// -v                            verbosity level. -v (errors only), -vv
-//                               (warnings and errors), -vvv (everything).
+// -v                            verbosity level. -v (errors only), -vv (warnings and errors),
+//                               -vvv (everything).
+// -P                            Port to use for all connections.
 // -d, --data=VALUE              Path to the input JSON data.
 //
 // Examples:
 // php -f test.php -- import -vvv -d test.json
 
+Cli\display_error_and_exit('Looks like something went wrong!', 'Fatal Error');
+// Fatal Error
+// Looks like something went wrong!
+
 ```
 
 ## Support
 
-If you believe you have found a bug, please report it using the [GitHub issue tracker](https://github.com/pointybeard/helpers-functions-cli/issues),
-or better yet, fork the library and submit a pull request.
+If you believe you have found a bug, please report it using the [GitHub issue tracker](https://github.com/pointybeard/helpers-functions-cli/issues), or better yet, fork the library and submit a pull request.
 
 ## Contributing
 

composer.json

@@ -1,9 +1,13 @@
 {
     "name": "pointybeard/helpers-functions-cli",
-    "version": "1.1.4",
     "description": "A collection of functions relating to the command-line",
     "homepage": "https://github.com/pointybeard/helpers-functions-cli",
     "license": "MIT",
+    "minimum-stability": "stable",
+    "support": {
+        "issues": "https://github.com/pointybeard/helpers-functions-cli/issues",
+        "wiki": "https://github.com/pointybeard/helpers-functions-cli/wiki"
+    },
     "authors": [
         {
             "name": "Alannah Kearney",
@@ -14,22 +18,34 @@
     ],
     "require": {
         "php": ">=7.2",
-        "pointybeard/helpers-cli-input": "~1",
-        "pointybeard/helpers-cli-colour": "~1",
+        "pointybeard/helpers-cli-input": "~1.2.0",
+        "pointybeard/helpers-cli-colour": "~1.0",
         "pointybeard/helpers-functions-strings": "~1.1",
-        "pointybeard/helpers-functions-flags": "~1"
+        "pointybeard/helpers-functions-flags": "~1.0",
+        "pointybeard/helpers-functions-arrays": "~1.0",
+        "pointybeard/helpers-functions-debug": "~1.0",
+        "pointybeard/helpers-exceptions-readabletrace": "~1.0.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "^8"
+        "friendsofphp/php-cs-fixer": "^3.0",
+        "squizlabs/php_codesniffer": "^3.0",
+        "damianopetrungaro/php-commitizen": "^0.1.0",
+        "php-parallel-lint/php-parallel-lint": "^1.0",
+        "php-parallel-lint/php-console-highlighter": "^0.5.0"
     },
-    "support": {
-        "issues": "https://github.com/pointybeard/helpers-functions-cli/issues",
-        "wiki": "https://github.com/pointybeard/helpers-functions-cli/wiki"
-    },
-    "minimum-stability": "stable",
     "autoload": {
+        "psr-4": {
+            "pointybeard\\Helpers\\Functions\\": "src/"
+        },
         "files": [
             "src/Cli/Cli.php"
         ]
+    },
+    "scripts": {
+        "tidy": "php-cs-fixer fix -v --using-cache=no",
+        "tidyDry": "@tidy --dry-run",
+        "test": [
+            "parallel-lint . --exclude vendor"
+        ]
     }
 }

src/Cli/Cli.php

@@ -2,13 +2,117 @@
 
 declare(strict_types=1);
 
+/*
+ * This file is part of the "PHP Helpers: Command-line Functions" repository.
+ *
+ * Copyright 2019-2021 Alannah Kearney <hi@alannahkearney.com>
+ *
+ * For the full copyright and license information, please view the LICENCE
+ * file that was distributed with this source code.
+ */
+
 namespace pointybeard\Helpers\Functions\Cli;
 
-use pointybeard\Helpers\Cli\Input;
+use Exception;
 use pointybeard\Helpers\Cli\Colour;
+use pointybeard\Helpers\Cli\Input;
+use pointybeard\Helpers\Functions\Arrays;
+use pointybeard\Helpers\Functions\Debug;
 use pointybeard\Helpers\Functions\Flags;
 use pointybeard\Helpers\Functions\Strings;
 
+/*
+ * Uses proc_open() to run a command on the shell. Output and errors are captured
+ * and returned. If the command "fails" to run (i.e. return code is != 0), this
+ * function will throw an exception.
+ *
+ * Note that some commands will return a non-zero status code to signify, for
+ * example, no results found. This function is unable to tell the difference and
+ * will trigger an exception regardless. In this instance, It is advised to trap
+ * that exception and inspect both $stderr and $stdout to decide if it was
+ * actually due to failed command execution.
+ *
+ * @param string $command the full bash command to run
+ * @param string $stdout  (optional) reference to capture output from STDOUT
+ * @param string $stderr  (optional) reference to capture output from STDERR
+ * #param string $exitCode (options) reference to capture the command exit code
+ *
+ * @throws RunCommandFailedException
+ */
+if (!function_exists(__NAMESPACE__.'\run_command')) {
+    function run_command(string $command, string &$stdout = null, string &$stderr = null, int &$exitCode = null): void
+    {
+        $pipes = null;
+        $exitCode = null;
+
+        $proc = proc_open(
+            "{$command};echo $? >&3",
+            [
+                0 => ['pipe', 'r'], // STDIN
+                1 => ['pipe', 'w'], // STDOUT
+                2 => ['pipe', 'w'], // STDERR
+                3 => ['pipe', 'w'], // Used to capture the exit code
+            ],
+            $pipes,
+            getcwd(),
+            null
+        );
+
+        // Close STDIN stream
+        fclose($pipes[0]);
+
+        // (guard) proc_open failed to return a resource
+        if (false == is_resource($proc)) {
+            throw new Exceptions\RunCommandFailedException($command, 'proc_open() returned FALSE.');
+        }
+
+        // Get contents of STDOUT and close stream
+        $stdout = trim(stream_get_contents($pipes[1]));
+        fclose($pipes[1]);
+
+        // Get contents od STDERR and close stream
+        $stderr = trim(stream_get_contents($pipes[2]));
+        fclose($pipes[2]);
+
+        // Grab the exit code then close the stream
+        if (false == feof($pipes[3])) {
+            $exitCode = (int) trim(stream_get_contents($pipes[3]));
+        }
+        fclose($pipes[3]);
+
+        // Close the process we created
+        proc_close($proc);
+
+        // (guard) proc_close return indiciated a failure
+        if (0 != $exitCode) {
+            // There was some kind of error. Throw an exception.
+            // If STDERR is empty, in effort to give back something
+            // meaningful, grab contents of STDOUT instead
+            throw new Exceptions\RunCommandFailedException($command, true == empty(trim($stderr)) ? $stdout : $stderr);
+        }
+    }
+}
+
+/*
+ * Returns the pathname for a specified command (or null if it cannot be found)
+ *
+ * @params $command the name of the command to look for
+ *
+ * @returns string|null
+ */
+if (!function_exists(__NAMESPACE__.'\which')) {
+    function which(string $command): ?string
+    {
+        try {
+            run_command("which {$command}", $output);
+        } catch (Exception $ex) {
+            $output = null;
+        }
+
+        return $output;
+    }
+}
+
 /*
  * Checks if bash can be invoked.
  *
@@ -38,31 +142,7 @@ if (!function_exists(__NAMESPACE__.'is_su')) {
     }
 }
 
-if (!function_exists(__NAMESPACE__.'usage')) {
-    function usage(string $name, Input\InputCollection $collection): string
-    {
-        $arguments = [];
-        foreach ($collection->getArguments() as $a) {
-            $arguments[] = strtoupper(
-                // Wrap with square brackets if it's not required
-                Flags\is_flag_set(Input\AbstractInputType::FLAG_OPTIONAL, $a->flags()) ||
-                !Flags\is_flag_set(Input\AbstractInputType::FLAG_REQUIRED, $a->flags())
-                    ? "[{$a->name()}]"
-                    : $a->name()
-            );
-        }
-        $arguments = trim(implode($arguments, ' '));
-
-        return sprintf(
-            'Usage: %s [OPTIONS]... %s%s',
-            $name,
-            $arguments,
-            strlen($arguments) > 0 ? '...' : ''
-        );
-    }
-}
-
-/**
+/*
  * Uses tput to find out the size of the window (columns and lines)
  * @return array an array containing exactly 2 items: 'cols' and 'lines'
  */
@@ -76,16 +156,40 @@ if (!function_exists(__NAMESPACE__.'get_window_size')) {
     }
 }
 
+if (!function_exists(__NAMESPACE__.'usage')) {
+    function usage(string $name, Input\InputCollection $collection): string
+    {
+        $arguments = [];
+        foreach ($collection->getItemsByType('Argument') as $a) {
+            $arguments[] = strtoupper(
+                // Wrap with square brackets if it's not required
+                Flags\is_flag_set(Input\AbstractInputType::FLAG_OPTIONAL, $a->flags()) ||
+                !Flags\is_flag_set(Input\AbstractInputType::FLAG_REQUIRED, $a->flags())
+                    ? "[{$a->name()}]"
+                    : $a->name()
+            );
+        }
+        $arguments = trim(implode(' ', $arguments));
+
+        return sprintf(
+            'Usage: %s [OPTIONS]... %s%s',
+            $name,
+            $arguments,
+            strlen($arguments) > 0 ? '...' : ''
+        );
+    }
+}
+
 if (!function_exists(__NAMESPACE__.'manpage')) {
-    function manpage(string $name, string $version, string $description, Input\InputCollection $collection, $foregroundColour=Colour\Colour::FG_DEFAULT, $headingColour=Colour\Colour::FG_WHITE, array $additionalSections=[]): string
+    function manpage(string $name, string $version, string $description, Input\InputCollection $collection, $foregroundColour = Colour\Colour::FG_DEFAULT, $headingColour = Colour\Colour::FG_WHITE, array $additionalSections = []): string
     {
         // Convienence function for wrapping a heading with colour
-        $heading = function(string $input) use ($headingColour) {
+        $heading = function (string $input) use ($headingColour) {
             return Colour\Colour::colourise($input, $headingColour);
         };
 
         // Convienence function for wrapping input in a specified colour
-        $colourise = function(string $input) use ($foregroundColour) {
+        $colourise = function (string $input) use ($foregroundColour) {
             return Colour\Colour::colourise($input, $foregroundColour);
         };
 
@@ -102,32 +206,109 @@ if (!function_exists(__NAMESPACE__.'manpage')) {
         $arguments = [];
         $options = [];
 
-        foreach ($collection->getArguments() as $a) {
+        foreach ($collection->getItemsByType('Argument') as $a) {
             $arguments[] = (string) $a;
         }
 
-        foreach ($collection->getOptions() as $o) {
+        foreach ($collection->getItemsExcludeByType('Argument') as $o) {
             $options[] = (string) $o;
         }
 
         // Add the arguments, if there are any.
-        if(false === empty($arguments)){
-            $sections[] = $heading("Arguments:");
-            $sections[] = $colourise(implode($arguments, PHP_EOL)) . PHP_EOL;
+        if (false === empty($arguments)) {
+            $sections[] = $heading('Arguments:');
+            $sections[] = $colourise(implode(PHP_EOL, $arguments)).PHP_EOL;
         }
 
         // Add the options, if there are any.
-        if(false === empty($options)){
-            $sections[] = $heading("Options:");
-            $sections[] = $colourise(implode($options, PHP_EOL)) . PHP_EOL;
+        if (false === empty($options)) {
+            $sections[] = $heading('Options:');
+            $sections[] = $colourise(implode(PHP_EOL, $options)).PHP_EOL;
         }
 
         // Iterate over all additional items and add them as new sections
-        foreach($additionalSections as $name => $contents) {
+        foreach ($additionalSections as $name => $contents) {
             $sections[] = $heading("{$name}:");
-            $sections[] = $colourise($contents) . PHP_EOL;
+            $sections[] = $colourise($contents).PHP_EOL;
         }
 
-        return implode($sections, PHP_EOL);
+        return implode(PHP_EOL, $sections);
+    }
+}
+
+if (!function_exists(__NAMESPACE__."\display_error_and_exit")) {
+    function display_error_and_exit($message, $heading = 'Error', $background = Colour\Colour::BG_RED, ?array $trace = null): void
+    {
+        $padCharacter = ' ';
+        $paddingBufferSize = 0.15; // 15%
+        $minimumWindowWidth = 40;
+        $edgePaddingLength = 5;
+        $edgePadding = str_repeat($padCharacter, $edgePaddingLength);
+
+        // Convenience function for adding the background to a line.
+        $add_background = function (string $string, bool $bold = false) use ($edgePadding, $background): string {
+            $string = $edgePadding.$string.$edgePadding;
+
+            return Colour\Colour::colourise(
+                $string,
+                (
+                    true == $bold
+                        ? Colour\Colour::FG_WHITE
+                        : Colour\Colour::FG_DEFAULT
+                ),
+                $background
+            );
+        };
+
+        // Get the window dimensions but restrict width to minimum
+        // of $minimumWindowWidth
+        $window = get_window_size();
+        $window['cols'] = max($minimumWindowWidth, $window['cols']);
+
+        // This shrinks the total line length (derived by the window width) by
+        // $paddingBufferSize
+        $paddingBuffer = (int) ceil($window['cols'] * $paddingBufferSize);
+
+        $lineLength = $window['cols'] - (2 * $edgePaddingLength) - $paddingBuffer;
+
+        $emptyLine = $add_background(str_repeat($padCharacter, $lineLength), true);
+        $heading = Strings\mb_str_pad(trim($heading), $lineLength, $padCharacter, \STR_PAD_RIGHT);
+
+        $message = Strings\utf8_wordwrap_array($message, $lineLength, PHP_EOL, true);
+
+        // Remove surrounding whitespace
+        $message = array_map('trim', $message);
+
+        // Remove empty elements from the array
+        $message = Arrays\array_remove_empty($message);
+
+        // Reset array indicies
+        $message = array_values($message);
+
+        // Wrap everything in red
+        for ($ii = 0; $ii < count($message); ++$ii) {
+            $message[$ii] = $add_background(Strings\mb_str_pad(
+                $message[$ii],
+                mb_strlen($heading),
+                $padCharacter,
+                \STR_PAD_RIGHT
+            ));
+        }
+
+        // Add an empty red line at the end
+        array_push($message, $emptyLine);
+
+        // Print the error message, starting with an empty red line
+        printf(
+            "\r\n%s\r\n%s\r\n%s\r\n%s",
+            $emptyLine,
+            $add_background($heading, true),
+            implode(PHP_EOL, $message),
+            !empty($trace) && count($trace) > 0
+                ? PHP_EOL.sprintf("Trace\r\n==========\r\n%s\r\n", Debug\readable_debug_backtrace($trace))
+                : ''
+        );
+
+        exit(1);
     }
 }

src/Cli/Exceptions/RunCommandFailedException.php

@@ -0,0 +1,40 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the "PHP Helpers: Command-line Functions" repository.
+ *
+ * Copyright 2019-2021 Alannah Kearney <hi@alannahkearney.com>
+ *
+ * For the full copyright and license information, please view the LICENCE
+ * file that was distributed with this source code.
+ */
+
+namespace pointybeard\Helpers\Functions\Cli\Exceptions;
+
+use pointybeard\Helpers\Exceptions\ReadableTrace;
+
+class RunCommandFailedException extends ReadableTrace\ReadableTraceException
+{
+    private $command;
+
+    private $error;
+
+    public function __construct(string $command, string $error, int $code = 0, \Exception $previous = null)
+    {
+        $this->command = $command;
+        $this->error = $error;
+        parent::__construct("Failed to run command. Returned: {$error}", $code, $previous);
+    }
+
+    public function getCommand(): string
+    {
+        return $this->command;
+    }
+
+    public function getError(): string
+    {
+        return $this->error;
+    }
+}