Can pace be slowed of warnings and errors?

[karmatosed]

One thing I noticed when using this for example in Additional CSS, was how fast the warnings/errors appear. It really was as soon as I was typing. It got me thinking about how not everyone types as fast as it may be expecting. Could some delay be added?

[melchoyce]

Yeah, this is kind of alarming. Let's see if we can delay this error.

[obenland]

It can be slowed but I'm not sure what a good threshold would be. It's almost certain that you'll run into that again, even if we delayed it.

[westonruter]

What do IDEs like PhpStorm do?

Maybe the error should have a 1-second denounced delay while typing but then immediately show errors upon blur.

[westonruter]

Here's a proof of concept for something:

diff --git a/codemirror-wp.php b/codemirror-wp.php
index ac9c61f..45fc7a9 100644
--- a/codemirror-wp.php
+++ b/codemirror-wp.php
@@ -156,7 +156,9 @@ class CodeMirror_WP {
 				self::$options = array_merge( self::$options, array(
 					'mode'    => 'text/css',
 					'gutters' => array( 'CodeMirror-lint-markers' ),
-					'lint'    => true,
+					'lint'    => array(
+						'lintOnChange' => false,
+					),
 				) );
 				break;
 
@@ -289,10 +291,20 @@ class CodeMirror_WP {
 	 * Integrate with admin editor.
 	 */
 	public static function do_codemirror_admin_editor() {
+		wp_print_scripts( array( 'underscore' ) );
 		?>
 		<script>
 		jQuery( function() {
-			wp.codemirror = window.CodeMirror.fromTextArea( document.getElementById( 'newcontent' ), <?php echo json_encode( self::$options ); ?> );
+			var options = <?php echo json_encode( self::$options ); ?>;
+			wp.codemirror = window.CodeMirror.fromTextArea( document.getElementById( 'newcontent' ), options );
+			if ( options.lint ) {
+				wp.codemirror.on( 'change', _.debounce( function() {
+					wp.codemirror.performLint();
+				}, 1000 ) );
+				wp.codemirror.on( 'blur', function( editor ) {
+					wp.codemirror.performLint();
+				});
+			}
 		} );
 		</script>
 		<?php

Naturally JS here needs to be refactored to apply to each place where CodeMirror is used. Also, it would probably be nice to performLint immediately after a change happens if there was a new linting error introduced, or maybe shorten the delay, so that a user gets faster feedback once they have fixed the issue.

[westonruter]

Oh, there's also a delay option for the lint that could be used instead of the custom debounce here.

[westonruter]

diff --git a/codemirror-wp.php b/codemirror-wp.php
index ac9c61f..d7bfaa6 100644
--- a/codemirror-wp.php
+++ b/codemirror-wp.php
@@ -156,7 +156,9 @@ class CodeMirror_WP {
 				self::$options = array_merge( self::$options, array(
 					'mode'    => 'text/css',
 					'gutters' => array( 'CodeMirror-lint-markers' ),
-					'lint'    => true,
+					'lint'    => array(
+						'delay' => 1000,
+					),
 				) );
 				break;
 
@@ -292,7 +294,13 @@ class CodeMirror_WP {
 		?>
 		<script>
 		jQuery( function() {
-			wp.codemirror = window.CodeMirror.fromTextArea( document.getElementById( 'newcontent' ), <?php echo json_encode( self::$options ); ?> );
+			var options = <?php echo json_encode( self::$options ); ?>;
+			wp.codemirror = window.CodeMirror.fromTextArea( document.getElementById( 'newcontent' ), options );
+			if ( options.lint ) {
+				wp.codemirror.on( 'blur', function( editor ) {
+					wp.codemirror.performLint();
+				});
+			}
 		} );
 		</script>
 		<?php

[westonruter]

Also, instead of linting upon changing, it could be particularly helpful to lint upon hitting Enter or an arrow key, as that is somewhat of an indication that a user has “finished” what they were doing and would want feedback. So the delay could be set to 3 seconds, and then immediately performLint upon blur or when doing a keypress of ⬆️, ⬇️, or Enter.

[westonruter]

This has essentially been implemented in #69, though it's the error notice about not being able to save that is deferred until blur instead of the error indicators in the gutter.

[melchoyce]

Any way we can enhance it further by not showing the "this rule is empty" for CSS stuff until you're outside of the brackets? It's super distracting to try to write something and have the warning pop up before I even have a chance to type anything.

[westonruter]

We could just disable the “empty rule” rule?