init commit

.github/workflows/release.yml

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+# This workflow will run tests using node and then publish a package to GitHub Packages when a release is created
+# For more information see: https://help.github.com/actions/language-and-framework-guides/publishing-nodejs-packages
+
+name: NPM Publish
+
+on:
+  release:
+    types: [created]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-node@v3
+        with:
+          node-version: 18
+      - run: npm install --ignore-scripts --no-audit
+      - run: npm test
+
+  publish-npm:
+    needs: build
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-node@v3
+        with:
+          node-version: 18
+          registry-url: https://registry.npmjs.org/
+      - run: npm install --ignore-scripts --no-audit
+      - run: npm run build
+      - run: npm publish
+        env:
+          NODE_AUTH_TOKEN: ${{secrets.NPM_TOKEN}}

.github/workflows/test.yml

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+# This workflow will do a clean install of node dependencies, build the source code and run tests across different versions of node
+# For more information see: https://help.github.com/actions/language-and-framework-guides/using-nodejs-with-github-actions
+
+name: Tests
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  test:
+    name: Unit tests
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Use Node.js 20
+        uses: actions/setup-node@v3
+        with:
+          node-version: 20
+          cache: "npm"
+      - run: npm install --ignore-scripts --no-audit
+      - run: npm test

.gitignore

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+node_modules
+dist

README.md

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+# minify-css
+
+Fast, small, zero-config library to minify CSS with basic rules. Simplicity, bundle size and runtime speed are more important than versatility and extensibility.
+
+## Installation
+
+```
+npm install @projectwallace/minify-css
+```
+
+## Usage
+
+```js
+import { minify } from "@projectwallace/minify-css";
+
+let old_css = "/* Your CSS here */";
+let new_css = minify(old_css);
+```
+
+TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO Need more examples?
+
+- [StackBlitz example using CommonJS](https://stackblitz.com/edit/stackblitz-starters-phchci?file=index.js)
+- [StackBlitz example using ES Modules](https://stackblitz.com/edit/stackblitz-starters-hrhsed?file=index.js)
+
+## Acknowledgements
+
+- Thanks to [CSSTree](https://github.com/csstree/csstree) for providing the necessary parser and the interfaces for our CSS Types (the **bold** elements in the list above)
+
+## Related projects
+
+- [Minify CSS online](https://www.projectwallace.com/minify-css?utm_source=github&utm_medium=wallace_minify_css_related_projects) - See this minifier in action online!
+- [CSS Analyzer](https://github.com/projectwallace/css-analyzer) - The best CSS analyzer that powers all analysis on [projectwallace.com](https://www.projectwallace.com?utm_source=github&utm_medium=wallace_minify_css_related_projects)
+- [Format CSS](https://github.com/projectwallace/format-css) The exact opposite of this library: fast, small, zero-config CSS formatter.

index.js

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+import { parse } from 'css-tree'
+
+/**
+ * @param {import('css-tree').CssNode} node
+ * @param {string} css
+ */
+function substr(node, css) {
+	if (!node.loc) return ''
+	let str = css.substring(node.loc.start.offset, node.loc.end.offset)
+
+	// Single-line node, most common case
+	if (node.loc.start.line === node.loc.end.line) {
+		return str
+	}
+
+	// Multi-line nodes, not common
+	return str.replace(/\n/g, ' ')
+}
+
+/**
+ * @param {import('css-tree').Rule} node
+ * @param {string} css
+ */
+function print_rule(node, css) {
+	let buffer = ''
+
+	if (node.prelude !== null) {
+		if (node.prelude.type === 'SelectorList') {
+			buffer += print_selectorlist(node.prelude, css)
+		}
+	}
+
+	if (node.block !== null && node.block.type === 'Block') {
+		buffer += print_block(node.block, css)
+	}
+
+	return buffer
+}
+
+/**
+ * @param {import('css-tree').SelectorList} node
+ * @param {string} css
+ */
+function print_selectorlist(node, css) {
+	let buffer = ''
+
+	for (let selector of node.children) {
+		if (selector.type === 'Selector') {
+			buffer += substr(selector, css)
+		}
+
+		if (selector !== node.children.last) {
+			buffer += ','
+		}
+	}
+	return buffer
+}
+
+/**
+ * @param {import('css-tree').Block} node
+ * @param {string} css
+ */
+function print_block(node, css) {
+	let children = node.children
+
+	if (children.isEmpty) {
+		return '{}'
+	}
+
+	let buffer = '{'
+
+	for (let child of children) {
+		if (child.type === 'Declaration') {
+			buffer += print_declaration(child, css)
+			if (child !== children.last) {
+				buffer += ';'
+			}
+		} else if (child.type === 'Rule') {
+			buffer += print_rule(child, css)
+		} else if (child.type === 'Atrule') {
+			buffer += print_atrule(child, css)
+		}
+	}
+
+	buffer += '}'
+
+	return buffer
+}
+
+/**
+ * @param {import('css-tree').Atrule} node
+ * @param {string} css
+ */
+function print_atrule(node, css) {
+	let buffer = '@' + node.name + ' '
+
+	// @font-face has no prelude
+	if (node.prelude) {
+		buffer += substr(node.prelude, css).replace(/\s+/g, ' ')
+	}
+
+	if (node.block && node.block.type === 'Block') {
+		buffer += print_block(node.block, css)
+	} else {
+		// `@import url(style.css);` has no block, neither does `@layer layer1;`
+		buffer += ';'
+	}
+
+	return buffer
+}
+
+/**
+ * @param {import('css-tree').Declaration} node
+ * @param {string} css
+ */
+function print_declaration(node, css) {
+	return node.property + ':' + substr(node.value, css)
+}
+
+/**
+ * @param {import('css-tree').CssNode} node
+ * @param {string} css
+ */
+function print(node, css) {
+	let buffer = ''
+
+	if (node.children !== null) {
+		let children = node.children
+
+		for (let child of children) {
+			if (child.type === 'Rule') {
+				buffer += print_rule(child, css)
+			} else if (child.type === 'Atrule') {
+				buffer += print_atrule(child, css)
+			}
+		}
+	}
+
+	return buffer
+}
+
+/** @param {string} css */
+export function minify(css) {
+	let ast = parse(css, {
+		positions: true,
+		parseAtrulePrelude: false,
+		parseCustomProperty: false,
+		parseValue: false
+	})
+	return print(ast, css)
+}