summaryrefslogtreecommitdiff
path: root/23.10.1/guides/rainbow_bracket_queries.html
blob: 98f11d997d1843580b26715f152258550460dbe0 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
<!DOCTYPE HTML>
<html lang="en" class="colibri" dir="ltr">
    <head>
        <!-- Book generated using mdBook -->
        <meta charset="UTF-8">
        <title>Adding rainbow bracket queries</title>


        <!-- Custom HTML head -->
        
        <meta name="description" content="">
        <meta name="viewport" content="width=device-width, initial-scale=1">
        <meta name="theme-color" content="#ffffff">

        <link rel="icon" href="../favicon.svg">
        <link rel="shortcut icon" href="../favicon.png">
        <link rel="stylesheet" href="../css/variables.css">
        <link rel="stylesheet" href="../css/general.css">
        <link rel="stylesheet" href="../css/chrome.css">
        <link rel="stylesheet" href="../css/print.css" media="print">

        <!-- Fonts -->
        <link rel="stylesheet" href="../FontAwesome/css/font-awesome.css">
        <link rel="stylesheet" href="../fonts/fonts.css">

        <!-- Highlight.js Stylesheets -->
        <link rel="stylesheet" href="../highlight.css">
        <link rel="stylesheet" href="../tomorrow-night.css">
        <link rel="stylesheet" href="../ayu-highlight.css">

        <!-- Custom theme stylesheets -->
        <link rel="stylesheet" href="../custom.css">

    </head>
    <body class="sidebar-visible no-js">
    <div id="body-container">
        <!-- Provide site root to javascript -->
        <script>
            var path_to_root = "../";
            var default_theme = window.matchMedia("(prefers-color-scheme: dark)").matches ? "colibri" : "colibri";
        </script>

        <!-- Work around some values being stored in localStorage wrapped in quotes -->
        <script>
            try {
                var theme = localStorage.getItem('mdbook-theme');
                var sidebar = localStorage.getItem('mdbook-sidebar');

                if (theme.startsWith('"') && theme.endsWith('"')) {
                    localStorage.setItem('mdbook-theme', theme.slice(1, theme.length - 1));
                }

                if (sidebar.startsWith('"') && sidebar.endsWith('"')) {
                    localStorage.setItem('mdbook-sidebar', sidebar.slice(1, sidebar.length - 1));
                }
            } catch (e) { }
        </script>

        <!-- Set the theme before any content is loaded, prevents flash -->
        <script>
            var theme;
            try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { }
            if (theme === null || theme === undefined) { theme = default_theme; }
            var html = document.querySelector('html');
            html.classList.remove('colibri')
            html.classList.add(theme);
            var body = document.querySelector('body');
            body.classList.remove('no-js')
            body.classList.add('js');
        </script>

        <input type="checkbox" id="sidebar-toggle-anchor" class="hidden">

        <!-- Hide / unhide sidebar before it is displayed -->
        <script>
            var body = document.querySelector('body');
            var sidebar = null;
            var sidebar_toggle = document.getElementById("sidebar-toggle-anchor");
            if (document.body.clientWidth >= 1080) {
                try { sidebar = localStorage.getItem('mdbook-sidebar'); } catch(e) { }
                sidebar = sidebar || 'visible';
            } else {
                sidebar = 'hidden';
            }
            sidebar_toggle.checked = sidebar === 'visible';
            body.classList.remove('sidebar-visible');
            body.classList.add("sidebar-" + sidebar);
        </script>

        <nav id="sidebar" class="sidebar" aria-label="Table of contents">
            <div class="sidebar-scrollbox">
                <ol class="chapter"><li class="chapter-item expanded affix "><a href="../title-page.html">Helix</a></li><li class="chapter-item expanded "><a href="../install.html"><strong aria-hidden="true">1.</strong> Installation</a></li><li class="chapter-item expanded "><a href="../usage.html"><strong aria-hidden="true">2.</strong> Usage</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../keymap.html"><strong aria-hidden="true">2.1.</strong> Keymap</a></li><li class="chapter-item expanded "><a href="../commands.html"><strong aria-hidden="true">2.2.</strong> Commands</a></li><li class="chapter-item expanded "><a href="../lang-support.html"><strong aria-hidden="true">2.3.</strong> Language support</a></li></ol></li><li class="chapter-item expanded "><a href="../from-vim.html"><strong aria-hidden="true">3.</strong> Migrating from Vim</a></li><li class="chapter-item expanded "><a href="../configuration.html"><strong aria-hidden="true">4.</strong> Configuration</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../themes.html"><strong aria-hidden="true">4.1.</strong> Themes</a></li><li class="chapter-item expanded "><a href="../remapping.html"><strong aria-hidden="true">4.2.</strong> Key remapping</a></li><li class="chapter-item expanded "><a href="../languages.html"><strong aria-hidden="true">4.3.</strong> Languages</a></li></ol></li><li class="chapter-item expanded "><a href="../guides/index.html"><strong aria-hidden="true">5.</strong> Guides</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../guides/adding_languages.html"><strong aria-hidden="true">5.1.</strong> Adding languages</a></li><li class="chapter-item expanded "><a href="../guides/textobject.html"><strong aria-hidden="true">5.2.</strong> Adding textobject queries</a></li><li class="chapter-item expanded "><a href="../guides/indent.html"><strong aria-hidden="true">5.3.</strong> Adding indent queries</a></li><li class="chapter-item expanded "><a href="../guides/injection.html"><strong aria-hidden="true">5.4.</strong> Adding injection queries</a></li><li class="chapter-item expanded "><a href="../guides/rainbow_bracket_queries.html" class="active"><strong aria-hidden="true">5.5.</strong> Adding rainbow bracket queries</a></li></ol></li></ol>
            </div>
            <div id="sidebar-resize-handle" class="sidebar-resize-handle"></div>
        </nav>

        <!-- Track and set sidebar scroll position -->
        <script>
            var sidebarScrollbox = document.querySelector('#sidebar .sidebar-scrollbox');
            sidebarScrollbox.addEventListener('click', function(e) {
                if (e.target.tagName === 'A') {
                    sessionStorage.setItem('sidebar-scroll', sidebarScrollbox.scrollTop);
                }
            }, { passive: true });
            var sidebarScrollTop = sessionStorage.getItem('sidebar-scroll');
            sessionStorage.removeItem('sidebar-scroll');
            if (sidebarScrollTop) {
                // preserve sidebar scroll position when navigating via links within sidebar
                sidebarScrollbox.scrollTop = sidebarScrollTop;
            } else {
                // scroll sidebar to current active section when navigating via "next/previous chapter" buttons
                var activeSection = document.querySelector('#sidebar .active');
                if (activeSection) {
                    activeSection.scrollIntoView({ block: 'center' });
                }
            }
        </script>

        <div id="page-wrapper" class="page-wrapper">

            <div class="page">
                                <div id="menu-bar-hover-placeholder"></div>
                <div id="menu-bar" class="menu-bar sticky">
                    <div class="left-buttons">
                        <label id="sidebar-toggle" class="icon-button" for="sidebar-toggle-anchor" title="Toggle Table of Contents" aria-label="Toggle Table of Contents" aria-controls="sidebar">
                            <i class="fa fa-bars"></i>
                        </label>
                        <button id="theme-toggle" class="icon-button" type="button" title="Change theme" aria-label="Change theme" aria-haspopup="true" aria-expanded="false" aria-controls="theme-list">
                            <i class="fa fa-paint-brush"></i>
                        </button>
                        <ul id="theme-list" class="theme-popup" aria-label="Themes" role="menu">
                            <li role="none"><button role="menuitem" class="theme" id="light">Light</button></li>
                            <li role="none"><button role="menuitem" class="theme" id="rust">Rust</button></li>
                            <li role="none"><button role="menuitem" class="theme" id="coal">Coal</button></li>
                            <li role="none"><button role="menuitem" class="theme" id="navy">Navy</button></li>
                            <li role="none"><button role="menuitem" class="theme" id="ayu">Ayu</button></li>
                            <li role="none"><button role="menuitem" class="theme" id="colibri">Colibri</button></li>
                        </ul>
                        <button id="search-toggle" class="icon-button" type="button" title="Search. (Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar">
                            <i class="fa fa-search"></i>
                        </button>
                    </div>

                    <h1 class="menu-title"></h1>

                    <div class="right-buttons">
                        <a href="../print.html" title="Print this book" aria-label="Print this book">
                            <i id="print-button" class="fa fa-print"></i>
                        </a>
                        <a href="https://github.com/helix-editor/helix" title="Git repository" aria-label="Git repository">
                            <i id="git-repository-button" class="fa fa-github"></i>
                        </a>
                        <a href="https://github.com/helix-editor/helix/edit/master/book/src/guides/rainbow_bracket_queries.md" title="Suggest an edit" aria-label="Suggest an edit">
                            <i id="git-edit-button" class="fa fa-edit"></i>
                        </a>

                    </div>
                </div>

                <div id="search-wrapper" class="hidden">
                    <form id="searchbar-outer" class="searchbar-outer">
                        <input type="search" id="searchbar" name="searchbar" placeholder="Search this book ..." aria-controls="searchresults-outer" aria-describedby="searchresults-header">
                    </form>
                    <div id="searchresults-outer" class="searchresults-outer hidden">
                        <div id="searchresults-header" class="searchresults-header"></div>
                        <ul id="searchresults">
                        </ul>
                    </div>
                </div>

                <!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM -->
                <script>
                    document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible');
                    document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible');
                    Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) {
                        link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1);
                    });
                </script>

                <div id="content" class="content">
                    <main>
                        <h1 id="adding-rainbow-bracket-queries"><a class="header" href="#adding-rainbow-bracket-queries">Adding Rainbow Bracket Queries</a></h1>
<p>Helix uses <code>rainbows.scm</code> tree-sitter query files to provide rainbow bracket
functionality.</p>
<p>Tree-sitter queries are documented in the tree-sitter online documentation.
If you're writing queries for the first time, be sure to check out the section
on <a href="https://tree-sitter.github.io/tree-sitter/syntax-highlighting#highlights">syntax highlighting queries</a> and on <a href="https://tree-sitter.github.io/tree-sitter/using-parsers#pattern-matching-with-queries">query syntax</a>.</p>
<p>Rainbow queries have two captures: <code>@rainbow.scope</code> and <code>@rainbow.bracket</code>.
<code>@rainbow.scope</code> should capture any node that increases the nesting level
while <code>@rainbow.bracket</code> should capture any bracket nodes. Put another way:
<code>@rainbow.scope</code> switches to the next rainbow color for all nodes in the tree
under it while <code>@rainbow.bracket</code> paints captured nodes with the current
rainbow color.</p>
<p>For an example, let's add rainbow queries for the tree-sitter query (TSQ)
language itself. These queries will go into a
<code>runtime/queries/tsq/rainbows.scm</code> file in the repository root.</p>
<p>First we'll add the <code>@rainbow.bracket</code> captures. TSQ only has parentheses and
square brackets:</p>
<pre><code class="language-tsq">[&quot;(&quot; &quot;)&quot; &quot;[&quot; &quot;]&quot;] @rainbow.bracket
</code></pre>
<p>The ordering of the nodes within the alternation (square brackets) is not
taken into consideration.</p>
<blockquote>
<p>Note: Why are these nodes quoted? Most syntax highlights capture text
surrounded by parentheses. These are <em>named nodes</em> and correspond to the
names of rules in the grammar. Brackets are usually written in tree-sitter
grammars as literal strings, for example:</p>
<pre><code class="language-js">{
  // ...
  arguments: seq(&quot;(&quot;, repeat($.argument), &quot;)&quot;),
  // ...
}
</code></pre>
<p>Nodes written as literal strings in tree-sitter grammars may be captured
in queries with those same literal strings.</p>
</blockquote>
<p>Then we'll add <code>@rainbow.scope</code> captures. The easiest way to do this is to
view the <code>grammar.js</code> file in the tree-sitter grammar's repository. For TSQ,
that file is <a href="https://github.com/the-mikedavis/tree-sitter-tsq/blob/48b5e9f82ae0a4727201626f33a17f69f8e0ff86/grammar.js">here</a>. As we scroll down the <code>grammar.js</code>, we
see that the <code>(alternation)</code>, (L36) <code>(group)</code> (L57), <code>(named_node)</code> (L59),
<code>(predicate)</code> (L87) and  <code>(wildcard_node)</code> (L97) nodes all contain literal
parentheses or square brackets in their definitions. These nodes are all
direct parents of brackets and happen to also be the nodes we want to change
to the next rainbow color, so we capture them as <code>@rainbow.scope</code>.</p>
<pre><code class="language-tsq">[
  (group)
  (named_node)
  (wildcard_node)
  (predicate)
  (alternation)
] @rainbow.scope
</code></pre>
<p>This strategy works as a rule of thumb for most programming and configuration
languages. Markup languages can be trickier and may take additional
experimentation to find the correct nodes to use for scopes and brackets.</p>
<p>The <code>:tree-sitter-subtree</code> command shows the syntax tree under the primary
selection in S-expression format and can be a useful tool for determining how
to write a query.</p>
<h3 id="properties"><a class="header" href="#properties">Properties</a></h3>
<p>The <code>rainbow.include-children</code> property may be applied to <code>@rainbow.scope</code>
captures. By default, all <code>@rainbow.bracket</code> captures must be direct descendant
of a node captured with <code>@rainbow.scope</code> in a syntax tree in order to be
highlighted. The <code>rainbow.include-children</code> property disables that check and
allows <code>@rainbow.bracket</code> captures to be highlighted if they are direct or
indirect descendants of some node captured with <code>@rainbow.scope</code>.</p>
<p>For example, this property is used in the HTML rainbow queries.</p>
<p>For a document like <code>&lt;a&gt;link&lt;/a&gt;</code>, the syntax tree is:</p>
<pre><code class="language-tsq">(element                   ; &lt;a&gt;link&lt;/a&gt;
  (start_tag               ; &lt;a&gt;
    (tag_name))            ; a
  (text)                   ; link
  (end_tag                 ; &lt;/a&gt;
    (tag_name)))           ; a
</code></pre>
<p>If we want to highlight the <code>&lt;</code>, <code>&gt;</code> and <code>&lt;/</code> nodes with rainbow colors, we
capture them as <code>@rainbow.bracket</code>:</p>
<pre><code class="language-tsq">[&quot;&lt;&quot; &quot;&gt;&quot; &quot;&lt;/&quot;] @rainbow.bracket
</code></pre>
<p>And we capture <code>(element)</code> as <code>@rainbow.scope</code> because <code>(element)</code> nodes nest
within each other: they increment the nesting level and switch to the next
color in the rainbow.</p>
<pre><code class="language-tsq">(element) @rainbow.scope
</code></pre>
<p>But this combination of <code>@rainbow.scope</code> and <code>@rainbow.bracket</code> will not
highlight any nodes. <code>&lt;</code>, <code>&gt;</code> and <code>&lt;/</code> are children of the <code>(start_tag)</code> and
<code>(end_tag)</code> nodes. We can't capture <code>(start_tag)</code> and <code>(end_tag)</code> as
<code>@rainbow.scope</code> because they don't nest other elements. We can fix this case
by removing the requirement that <code>&lt;</code>, <code>&gt;</code> and <code>&lt;/</code> are direct descendants of
<code>(element)</code> using the <code>rainbow.include-children</code> property.</p>
<pre><code class="language-tsq">((element) @rainbow.scope
 (#set! rainbow.include-children))
</code></pre>
<p>With this property set, <code>&lt;</code>, <code>&gt;</code>, and <code>&lt;/</code> will highlight with rainbow colors
even though they aren't direct descendents of the <code>(element)</code> node.</p>
<p><code>rainbow.include-children</code> is not necessary for the vast majority of programming
languages. It is only necessary when the node that increments the nesting level
(changes rainbow color) is not the direct parent of the bracket node.</p>

                    </main>

                    <nav class="nav-wrapper" aria-label="Page navigation">
                        <!-- Mobile navigation buttons -->
                            <a rel="prev" href="../guides/injection.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
                                <i class="fa fa-angle-left"></i>
                            </a>


                        <div style="clear: both"></div>
                    </nav>
                </div>
            </div>

            <nav class="nav-wide-wrapper" aria-label="Page navigation">
                    <a rel="prev" href="../guides/injection.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
                        <i class="fa fa-angle-left"></i>
                    </a>

            </nav>

        </div>




        <script>
            window.playground_copyable = true;
        </script>


        <script src="../elasticlunr.min.js"></script>
        <script src="../mark.min.js"></script>
        <script src="../searcher.js"></script>

        <script src="../clipboard.min.js"></script>
        <script src="../highlight.js"></script>
        <script src="../book.js"></script>

        <!-- Custom JS scripts -->


    </div>
    </body>
</html>