[11.x] Pick up existing views and markdowns when creating mails (#53308)

* pick up the existing mail template when creating new mails.

* Existing markdowns will be picked up when creating emails.

* display error messages when specified markdowns or views already exist.

* update the test cases for the make:mail command when markdowns and views already exist.

* rename a test case for the make:mail command.

src/Illuminate/Foundation/Console/MailMakeCommand.php

@@ -70,6 +70,10 @@ protected function writeMarkdownTemplate()
             str_replace('.', '/', $this->getView()).'.blade.php'
         );
 
+        if ($this->files->exists($path)) {
+            return $this->components->error(sprintf('%s [%s] already exists.', 'Markdown view', $path));
+        }
+
         $this->files->ensureDirectoryExists(dirname($path));
 
         $this->files->put($path, file_get_contents(__DIR__.'/stubs/markdown.stub'));
@@ -88,6 +92,10 @@ protected function writeView()
             str_replace('.', '/', $this->getView()).'.blade.php'
         );
 
+        if ($this->files->exists($path)) {
+            return $this->components->error(sprintf('%s [%s] already exists.', 'View', $path));
+        }
+
         $this->files->ensureDirectoryExists(dirname($path));
 
         $stub = str_replace(

tests/Integration/Generators/MailMakeCommandTest.php

@@ -47,6 +47,32 @@ public function testItCanGenerateMailFileWithMarkdownOption()
         ], 'resources/views/foo-mail.blade.php');
     }
 
+    public function testErrorsWillBeDisplayedWhenMarkdownsAlreadyExist()
+    {
+        $existingMarkdownPath = 'resources/views/existing-markdown.blade.php';
+        $this->app['files']
+            ->put(
+                $this->app->basePath($existingMarkdownPath),
+                '<x-mail::message>My existing markdown</x-mail::message>'
+            );
+        $this->artisan('make:mail', ['name' => 'FooMail', '--markdown' => 'existing-markdown'])
+            ->expectsOutputToContain('already exists.')
+            ->assertExitCode(0);
+
+        $this->assertFileContains([
+            'namespace App\Mail;',
+            'use Illuminate\Mail\Mailable;',
+            'class FooMail extends Mailable',
+            'return new Content(',
+            "markdown: 'existing-markdown',",
+        ], 'app/Mail/FooMail.php');
+        $this->assertFileContains([
+            '<x-mail::message>',
+            'My existing markdown',
+            '</x-mail::message>',
+        ], $existingMarkdownPath);
+    }
+
     public function testItCanGenerateMailFileWithViewOption()
     {
         $this->artisan('make:mail', ['name' => 'FooMail', '--view' => 'foo-mail'])
@@ -63,6 +89,31 @@ public function testItCanGenerateMailFileWithViewOption()
         $this->assertFilenameExists('resources/views/foo-mail.blade.php');
     }
 
+    public function testErrorsWillBeDisplayedWhenViewsAlreadyExist()
+    {
+        $existingViewPath = 'resources/views/existing-template.blade.php';
+        $this->app['files']
+            ->put(
+                $this->app->basePath($existingViewPath),
+                '<div>My existing template</div>'
+            );
+        $this->artisan('make:mail', ['name' => 'FooMail', '--view' => 'existing-template'])
+            ->expectsOutputToContain('already exists.')
+            ->assertExitCode(0);
+
+        $this->assertFileContains([
+            'namespace App\Mail;',
+            'use Illuminate\Mail\Mailable;',
+            'class FooMail extends Mailable',
+            'return new Content(',
+            "view: 'existing-template',",
+        ], 'app/Mail/FooMail.php');
+        $this->assertFilenameExists($existingViewPath);
+        $this->assertFileContains([
+            '<div>My existing template</div>',
+        ], $existingViewPath);
+    }
+
     public function testItCanGenerateMailFileWithTest()
     {
         $this->artisan('make:mail', ['name' => 'FooMail', '--test' => true])