CSS Navigation - VSCode Extension

Allows Go to Definition from HTML to CSS / Sass / Less, provides Completion and Workspace Symbols for class & id name, and supports Find References from CSS to HTML.

Features

Go to Definition and Peek Definition

In a HTML document, choose Go to definition or Peek definition, the extension will search related CSS & Scss & Less selectors in current workspace folder. Can also search selectors within nesting reference &... for Sass & Less.

The places you can find definitions:

• HTML (or files whose extension specified by activeHTMLFileExtensions option): <html-tag>, class="class-name", id="id-name".
• JSX & TSX: className="class-name", className={"class-name"}.
• CSS-like Document: custom-tag, .class-name, #id.

Note that the JSX template doesn't provide completion for attribute value by default, you may trigger it manually by clicking Ctrl + Space, or change settings:

editor.quickSuggestions": {
    "other": true,
    "comments": false,
    "strings": false
},

Workspace symbols

Allows to search workspace symbols in CSS & Scss & Less files across all activated workspace folders.

Class Name and ID Completion

Provides class name and id completion for your HTML files.

Note that the extension doesn't support remote sources, and doesn't follow the <link> tags in your HTML file to limit the completion results, it just lists all the defined class & id name in CSS & Scss & Less files in your workspace folders.

Find All References and Peek References

Supports looking for CSS selector references in your HTML files.

This functionality should not be very useful, and it needs to load and parse all the files configured in activeHTMLFileExtensions additionally. but if you love examining and refactoring CSS codes, at least it's much better than searching them in folders.

Features miscellaneous

• Can goto referenced files after clicking <link href="https://github.com/pucelle/vscode-css-navigation/blob/master/.."> or @import "...".
• Supports auto completion, goto definitions for inner style tags or css... template strings.

Configuration

Why started this project

At beginning, this project is a fork from vscode-css-peek, which uses vscode-css-languageservice as CSS parser, I just fixed some Scss nesting reference issues.

Then I found it eats so much CPU & memory. E.g., one of my project has 280 CSS files out of 5500 files, includes 6 MB codes. On my MacBook Pro, it needs 7s to load (1.3s to search files and 6s to parse), and uses 700 MB memory. Otherwise it keeps parsing files every time you input a character, if CSS document is more than 100 KB, CPU usage will keep high when inputting.

Finally I decided to implement a new css parser, which also supports Scss & Less naturally, as a result I created a new extension. The CSS parser is very simple and not 100% strict, but it's fast and very easy to extend. Now it costs about 0.8s to search files, and 0.5s to parse them. Memory usage in caching parsed results is only about 40 MB.

Otherwise, all the functionality will be started only when required by default, so CSS files are loaded only when you begin to search definitions or others.

After files loaded, The extension will track file and directory changes, creations, removals automatically, and reload them if needed.

Further more, I found the extension can support class name and id completion by the same core, so I do it with very few codes.

Finding references uses another core, I implement it because my work have a heavy CSS part, and I love refactoring CSS codes. I believe few people would need it.

Stress Test & Performance

I loaded 100 MB (0.9 M declarations, 2.8 M lines) CSS files for stress test, it took 8s to parse them, and used about 850 MB memory. After 1 minute, the memory usage fell back to 550 MB. Searching definitions across all 0.9 M declarations cost about 50ms, searching workspace symbols cost about 500ms, and searching completions cost about 230ms.

My environment is Win10, MacBook Pro 2014 version, with power on.

Plans & More

I just switched from Sublime Text to VSCode, and I love VSCode so much.

I have plans to make this extension grow, I hope it can serve more frontend developers like me.

So please give me your feedback. Thanks.

FAQ

Can I change definition order to make sass files always before the css files?

No, VSCode always sort the definition results, seems in name order. If you don't like duplicate css definitions, you can remove the css in activeCSSFileExtensions option, or compile css file to the same folder, and keep ignoreSameNameCSSFile as true.

From version 1.3.0 there is a ignoreFilesBy option, you may specify to ignore css files listed in your .gitignore.

Can't get definitions across all workspace folders

By default, definition searching is limited in the same workspace folder, that means when you choose Go to definition in a html file, the definitions you got are always come from the same workspace folder where the html file in. Searching references, completions also works like this.

If you have more than one folders in your workspace, and you definitely need to find definitions across them, set searchAcrossWorkspaceFolders to true.

Missed some workspace symbols

Workspace symbols are always come from multiple workspace folders, but for each workspace folder, you need to open one HTML or CSS file to activate it, then it will return results belong to it.

Set searchAcrossWorkspaceFolders to true will also activate services for all workspace folders as soon as possible, then you will get full workspace symbols always.

How the extension filter selectors?

This extension only compare the last part of the selector, the parts are defined by splitting selector by space or several other characters like >, +, '~'.

So when you are trying to find definitions for class="class1", these selectors will match: p .class1, p.class1, .class1.class2, .class2.class1, .class1:hover.

Searching tag definition is a little different, it must be the unique part of the selector, which means p will not match div p, but matches p:hover. This can prevent you got so many results.

Searching completion works in the same way.

Searching workspace symbols have a more strict rule than other extensions, which requires the start word boundary must match.

Many duplicate definitions got. Can you limit the results to only in files specified by <link> tags, or check parent nodes to ensure the whole selector match?

It sounds like a good idea. For a complete static project, It should be very easy to follow <link> tags, matching whole selector is much harder, but it can also be done.

But the Web architecture is extremely complex today, all you got in your hand may be just a piece of html codes, an unique class name, which cause we can't get enough information about the context.

My suggestion is using unique class name, avoid nesting, which would be also helpful for the code quality of you project.

If you prefer scoped style, and write html and css codes in the same file, searching definitions should be less important for you. But checking option alsoSearchDefinitionsInStyleTag will help you to search css definitions in the <style> inside your current document.

License

MIT