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
|
import type { Properties, Root } from 'hast';
import {
type BundledLanguage,
type LanguageRegistration,
type ShikiTransformer,
type ThemeRegistration,
type ThemeRegistrationRaw,
createCssVariablesTheme,
createHighlighter,
isSpecialLang,
} from 'shiki';
import type { ThemePresets } from './types.js';
export interface ShikiHighlighter {
codeToHast(
code: string,
lang?: string,
options?: ShikiHighlighterHighlightOptions,
): Promise<Root>;
codeToHtml(
code: string,
lang?: string,
options?: ShikiHighlighterHighlightOptions,
): Promise<string>;
}
export interface CreateShikiHighlighterOptions {
langs?: LanguageRegistration[];
theme?: ThemePresets | ThemeRegistration | ThemeRegistrationRaw;
themes?: Record<string, ThemePresets | ThemeRegistration | ThemeRegistrationRaw>;
}
export interface ShikiHighlighterHighlightOptions {
/**
* Generate inline code element only, without the pre element wrapper.
*/
inline?: boolean;
/**
* Enable word wrapping.
* - true: enabled.
* - false: disabled.
* - null: All overflow styling removed. Code will overflow the element by default.
*/
wrap?: boolean | null;
/**
* Chooses a theme from the "themes" option that you've defined as the default styling theme.
*/
defaultColor?: 'light' | 'dark' | string | false;
/**
* Shiki transformers to customize the generated HTML by manipulating the hast tree.
*/
transformers?: ShikiTransformer[];
/**
* Additional attributes to be added to the root code block element.
*/
attributes?: Record<string, string>;
/**
* Raw `meta` information to be used by Shiki transformers.
*/
meta?: string;
}
let _cssVariablesTheme: ReturnType<typeof createCssVariablesTheme>;
const cssVariablesTheme = () =>
_cssVariablesTheme ??
(_cssVariablesTheme = createCssVariablesTheme({ variablePrefix: '--astro-code-' }));
export async function createShikiHighlighter({
langs = [],
theme = 'github-dark',
themes = {},
}: CreateShikiHighlighterOptions = {}): Promise<ShikiHighlighter> {
theme = theme === 'css-variables' ? cssVariablesTheme() : theme;
const highlighter = await createHighlighter({
langs: ['plaintext', ...langs],
themes: Object.values(themes).length ? Object.values(themes) : [theme],
});
async function highlight(
code: string,
lang = 'plaintext',
options: ShikiHighlighterHighlightOptions,
to: 'hast' | 'html',
) {
const loadedLanguages = highlighter.getLoadedLanguages();
if (!isSpecialLang(lang) && !loadedLanguages.includes(lang)) {
try {
await highlighter.loadLanguage(lang as BundledLanguage);
} catch (_err) {
// eslint-disable-next-line no-console
console.warn(`[Shiki] The language "${lang}" doesn't exist, falling back to "plaintext".`);
lang = 'plaintext';
}
}
const themeOptions = Object.values(themes).length ? { themes } : { theme };
const inline = options?.inline ?? false;
return highlighter[to === 'html' ? 'codeToHtml' : 'codeToHast'](code, {
...themeOptions,
defaultColor: options.defaultColor,
lang,
// NOTE: while we can spread `options.attributes` here so that Shiki can auto-serialize this as rendered
// attributes on the top-level tag, it's not clear whether it is fine to pass all attributes as meta, as
// they're technically not meta, nor parsed from Shiki's `parseMetaString` API.
meta: options?.meta ? { __raw: options?.meta } : undefined,
transformers: [
{
pre(node) {
// Swap to `code` tag if inline
if (inline) {
node.tagName = 'code';
}
const {
class: attributesClass,
style: attributesStyle,
...rest
} = options?.attributes ?? {};
Object.assign(node.properties, rest);
const classValue =
(normalizePropAsString(node.properties.class) ?? '') +
(attributesClass ? ` ${attributesClass}` : '');
const styleValue =
(normalizePropAsString(node.properties.style) ?? '') +
(attributesStyle ? `; ${attributesStyle}` : '');
// Replace "shiki" class naming with "astro-code"
node.properties.class = classValue.replace(/shiki/g, 'astro-code');
// Add data-language attribute
node.properties.dataLanguage = lang;
// Handle code wrapping
// if wrap=null, do nothing.
if (options.wrap === false || options.wrap === undefined) {
node.properties.style = styleValue + '; overflow-x: auto;';
} else if (options.wrap === true) {
node.properties.style =
styleValue + '; overflow-x: auto; white-space: pre-wrap; word-wrap: break-word;';
}
},
line(node) {
// Add "user-select: none;" for "+"/"-" diff symbols.
// Transform `<span class="line"><span style="...">+ something</span></span>
// into `<span class="line"><span style="..."><span style="user-select: none;">+</span> something</span></span>`
if (lang === 'diff') {
const innerSpanNode = node.children[0];
const innerSpanTextNode =
innerSpanNode?.type === 'element' && innerSpanNode.children?.[0];
if (innerSpanTextNode && innerSpanTextNode.type === 'text') {
const start = innerSpanTextNode.value[0];
if (start === '+' || start === '-') {
innerSpanTextNode.value = innerSpanTextNode.value.slice(1);
innerSpanNode.children.unshift({
type: 'element',
tagName: 'span',
properties: { style: 'user-select: none;' },
children: [{ type: 'text', value: start }],
});
}
}
}
},
code(node) {
if (inline) {
return node.children[0] as typeof node;
}
},
},
...(options.transformers ?? []),
],
});
}
return {
codeToHast(code, lang, options = {}) {
return highlight(code, lang, options, 'hast') as Promise<Root>;
},
codeToHtml(code, lang, options = {}) {
return highlight(code, lang, options, 'html') as Promise<string>;
},
};
}
function normalizePropAsString(value: Properties[string]): string | null {
return Array.isArray(value) ? value.join(' ') : (value as string | null);
}
|
