chore: rename minify-css to preprocess-styles (#363)

Author: metonym

scripts/build-styles.ts

@@ -1,8 +1,8 @@
 import { $, Glob } from "bun";
 import path from "node:path";
 import { createMarkdown } from "./utils/create-markdown";
-import { minifyCss } from "./utils/minify-css";
 import { postcssScopedStyles } from "./utils/postcss-scoped-styles";
+import { preprocessStyles } from "./utils/preprocess-styles";
 import { toCamelCase } from "./utils/to-camel-case";
 import { writeTo } from "./utils/write-to";
 
@@ -37,14 +37,17 @@ export async function buildStyles() {
       styles.push({ name, moduleName });
 
       const content = await Bun.file(absPath).text();
-      const css_minified = minifyCss(content, {
+      const css_minified = preprocessStyles(content, {
         discardComments: "preserve-license",
       });
 
       // Escape backticks for JS template literal.
-      const content_css_for_js = minifyCss(content.replace(/\`/g, "\\`"), {
-        discardComments: "preserve-license",
-      });
+      const content_css_for_js = preprocessStyles(
+        content.replace(/\`/g, "\\`"),
+        {
+          discardComments: "preserve-license",
+        },
+      );
 
       const exportee = `const ${moduleName} = \`<style>${content_css_for_js}</style>\`;\n
       export default ${moduleName};\n`;
@@ -56,7 +59,7 @@ export async function buildStyles() {
       );
       await writeTo(`src/styles/${name}.css`, css_minified);
 
-      const scoped_style = minifyCss(content, {
+      const scoped_style = preprocessStyles(content, {
         discardComments: "remove-all",
         plugins: [postcssScopedStyles(moduleName)],
       });

scripts/utils/minify-css.ts scripts/utils/preprocess-styles.ts

@@ -5,7 +5,15 @@ import discardDuplicates from "postcss-discard-duplicates";
 import { inlineCssVars } from "postcss-inline-css-vars";
 import mergeRules from "postcss-merge-rules";
 
-export const minifyCss = (
+/**
+ * Raw styles from `highlight.js` are preprocessed for consistency.
+ * - Inlining CSS variables.
+ * - Discarding duplicate rules.
+ * - Merging rules.
+ * - Discarding comments (but preserving license comments).
+ * - Minifying the CSS.
+ */
+export const preprocessStyles = (
   css: string,
   options?: {
     plugins?: Plugin[];

tests/minify-css.test.ts tests/preprocess-styles.test.ts

@@ -1,14 +1,14 @@
-import { minifyCss } from "../scripts/utils/minify-css";
+import { preprocessStyles } from "../scripts/utils/preprocess-styles";
 
-describe("minifyCss", () => {
+describe("preprocessStyles", () => {
   it("should minify basic CSS", () => {
     const input = `
       .test {
         color: red;
         background: blue;
       }
     `;
-    const output = minifyCss(input);
+    const output = preprocessStyles(input);
     expect(output).toBe(".test{color:red;background:blue}");
   });
 
@@ -21,7 +21,7 @@ describe("minifyCss", () => {
         color: red;
       }
     `;
-    const output = minifyCss(input);
+    const output = preprocessStyles(input);
     expect(output).toBe(".test{color:red}");
   });
 
@@ -34,7 +34,7 @@ describe("minifyCss", () => {
         background: blue;
       }
     `;
-    const output = minifyCss(input);
+    const output = preprocessStyles(input);
     expect(output).toBe(".test{color:red;background:blue}");
   });
 
@@ -57,7 +57,7 @@ describe("minifyCss", () => {
     `;
 
     it("should preserve license comments when option is set", () => {
-      const output = minifyCss(cssWithComments, {
+      const output = preprocessStyles(cssWithComments, {
         discardComments: "preserve-license",
       });
       expect(output).toContain("@license");
@@ -66,7 +66,7 @@ describe("minifyCss", () => {
     });
 
     it("should remove all comments when remove-all option is set", () => {
-      const output = minifyCss(cssWithComments, {
+      const output = preprocessStyles(cssWithComments, {
         discardComments: "remove-all",
       });
       expect(output).not.toContain("@license");