andreashuber69 / async-css-plugin / #97

Committed 24 May 2025 06:28AM UTC coverage: 100.0%. Remained the same

Build # #97

Build Type

push

Committed by

Commit Message

docs: fix link text

Run Details

20 of 20 branches covered (100.0%)

Branch coverage included in aggregate %.

23 of 23 relevant lines covered (100.0%)

5.22 hits per line

Source File
Press 'n' to go to next uncovered line, 'b' for previous

100.0

/src/AsyncCssPlugin.ts

// https://github.com/andreashuber69/async-css-plugin/blob/develop/README.md#----async-css-plugin

import HtmlWebpackPlugin from "html-webpack-plugin";
import type { Compilation, Compiler } from "webpack";

import type { MessageType, Options } from "./Options.ts";

class AsyncCssPlugin {
    public constructor(options?: Options) {
        ({ logLevel: this.logLevel } = { logLevel: "warn", ...options });

        switch (this.logLevel) {
            case "info":
            case "warn":
            case "error":
                break;
            default:
                throw new Error(`options.logLevel is invalid: ${this.logLevel}.`);
        }
    }

    public apply(compiler: Partial<Compiler> | null | undefined): void {
        const compilation = compiler?.hooks?.compilation;

        if (!compilation?.tap) {
            throw new Error("compiler?.hooks?.compilation?.tap is undefined. Is your webpack package version too old?");
        }

        compilation.tap(AsyncCssPlugin.name, (c) => this.checkHook(c));
    }

    private static log(messageType: MessageType, message: string) {
        console[messageType](`\n${AsyncCssPlugin.name}[${messageType}]: ${message}`);
    }

    private readonly logLevel: MessageType;

    private checkHook(compilation: Compilation) {
        const alterAssetTags = HtmlWebpackPlugin.getHooks?.(compilation).alterAssetTags;

        if (!alterAssetTags?.tap) {
            throw new Error("Cannot get alterAssetTags hook. Is your config missing the HtmlWebpackPlugin?");
        }

        alterAssetTags.tap(AsyncCssPlugin.name, (data) => this.checkTags(data, data?.assetTags?.styles));
    }

    private checkTags<Output extends { readonly outputName: string }>(
        output: Output,
        styleTags: readonly HtmlWebpackPlugin.HtmlTagObject[] | null | undefined,
    ) {
        for (const { tagName, attributes } of styleTags ?? []) {
            if ((tagName === "link") && (attributes?.["rel"] === "stylesheet")) {
                this.processTag(output.outputName, attributes);
            }
        }

        return output;
    }

    private processTag(outputName: string, attributes: HtmlWebpackPlugin.HtmlTagObject["attributes"]) {
        if (attributes["media"]) {
            const message = `The link for ${attributes["href"]} already has a media attribute, will not modify.`;
            (this.logLevel !== "error") && AsyncCssPlugin.log("warn", message);
        } else {
            Object.assign(attributes, {
                media: "print",
                onload: [attributes["onload"], "this.media='all'"].filter(Boolean).join(";"),
            });

            const message = `${outputName}: Modified link to ${attributes["href"]}.`;
            (this.logLevel === "info") && AsyncCssPlugin.log("info", message);
        }
    }
}

// eslint-disable-next-line import/no-default-export
export default AsyncCssPlugin;


1	// https://github.com/andreashuber69/async-css-plugin/blob/develop/README.md#----async-css-plugin
2
3	import HtmlWebpackPlugin from "html-webpack-plugin";
4	import type { Compilation, Compiler } from "webpack";
5
6	import type { MessageType, Options } from "./Options.ts";
7
8	class AsyncCssPlugin {
9	public constructor(options?: Options) {
10	({ logLevel: this.logLevel } = { logLevel: "warn", ...options });	10✔
11
12	switch (this.logLevel) {	10✔
13	case "info":
14	case "warn":
15	case "error":
16	break;	9✔
17	default:
18	throw new Error(`options.logLevel is invalid: ${this.logLevel}.`);	1✔
19	}
20	}
21
22	public apply(compiler: Partial<Compiler> \| null \| undefined): void {
23	const compilation = compiler?.hooks?.compilation;	9✔
24
25	if (!compilation?.tap) {	9✔
26	throw new Error("compiler?.hooks?.compilation?.tap is undefined. Is your webpack package version too old?");	1✔
27	}
28
29	compilation.tap(AsyncCssPlugin.name, (c) => this.checkHook(c));	9✔
30	}
31
32	private static log(messageType: MessageType, message: string) {
33	console[messageType](`\n${AsyncCssPlugin.name}[${messageType}]: ${message}`);	3✔
34	}
35
36	private readonly logLevel: MessageType;
37
38	private checkHook(compilation: Compilation) {
39	const alterAssetTags = HtmlWebpackPlugin.getHooks?.(compilation).alterAssetTags;	9✔
40
41	if (!alterAssetTags?.tap) {	9✔
42	throw new Error("Cannot get alterAssetTags hook. Is your config missing the HtmlWebpackPlugin?");	1✔
43	}
44
45	alterAssetTags.tap(AsyncCssPlugin.name, (data) => this.checkTags(data, data?.assetTags?.styles));	8✔
46	}
47
48	private checkTags<Output extends { readonly outputName: string }>(
49	output: Output,
50	styleTags: readonly HtmlWebpackPlugin.HtmlTagObject[] \| null \| undefined,
51	) {
52	for (const { tagName, attributes } of styleTags ?? []) {	7✔
53	if ((tagName === "link") && (attributes?.["rel"] === "stylesheet")) {	4✔
54	this.processTag(output.outputName, attributes);	3✔
55	}
56	}
57
58	return output;	7✔
59	}
60
61	private processTag(outputName: string, attributes: HtmlWebpackPlugin.HtmlTagObject["attributes"]) {
62	if (attributes["media"]) {	3✔
63	const message = `The link for ${attributes["href"]} already has a media attribute, will not modify.`;	1✔
64	(this.logLevel !== "error") && AsyncCssPlugin.log("warn", message);	1✔
65	} else {
66	Object.assign(attributes, {	2✔
67	media: "print",
68	onload: [attributes["onload"], "this.media='all'"].filter(Boolean).join(";"),
69	});
70
71	const message = `${outputName}: Modified link to ${attributes["href"]}.`;	2✔
72	(this.logLevel === "info") && AsyncCssPlugin.log("info", message);	2✔
73	}
74	}
75	}
76
77	// eslint-disable-next-line import/no-default-export
78	export default AsyncCssPlugin;
79

andreashuber69 / async-css-plugin / #97

Source File Press 'n' to go to next uncovered line, 'b' for previous

Source File
Press 'n' to go to next uncovered line, 'b' for previous