Add CI workflow to compute diff between files dist files

.github/generate-dist-files-size-diff.mjs

@@ -0,0 +1,118 @@
+/**
+ * Generate a markdown table with the difference in size of the dist files between the base and the PR.
+ */
+
+/*
+Usage:
+```shell
+BASE_DIST_FILES='{"src/Autocomplete/assets/dist/controller.js":{"size":15382,"size_gz":3716,"size_brotli":3125},"src/Chartjs/assets/dist/controller.js":{"size":2281,"size_gz":771,"size_brotli":642},"src/Cropperjs/assets/dist/controller.js":{"size":1044,"size_gz":475,"size_brotli":371}}' \
+PR_DIST_FILES='{"src/Chartjs/assets/dist/controller.js":{"size":2281,"size_gz":771,"size_brotli":642},"src/Cropperjs/assets/dist/controller.js":{"size":1044,"size_gz":475,"size_brotli":371},"src/Cropperjs/assets/dist/style.min.css":{"size":32,"size_gz":66,"size_brotli":34},"src/Dropzone/assets/dist/controller.js":{"size":3199,"size_gz":816,"size_brotli":634}}' \
+  node .github/generate-dist-files-size-diff.mjs
+```
+ */
+
+if (!process.env.BASE_DIST_FILES) {
+    throw new Error('Missing or invalid "BASE_DIST_FILES" env variable.');
+}
+
+if (!process.env.PR_DIST_FILES) {
+    throw new Error('Missing or invalid "PR_DIST_FILES" env variable.');
+}
+
+/**
+ * Adapted from https://gist.github.com/zentala/1e6f72438796d74531803cc3833c039c?permalink_comment_id=4455218#gistcomment-4455218
+ * @param {number} bytes
+ * @param {number} digits
+ * @returns {string}
+ */
+function formatBytes(bytes, digits = 2) {
+    if (bytes === 0) {
+        return '0 B';
+    }
+    const sizes = [`B`, 'kB', 'MB'];
+    const i = Math.floor(Math.log(bytes) / Math.log(1024));
+
+    return parseFloat((bytes / Math.pow(1024, i)).toFixed(digits)) + ' ' + sizes[i];
+}
+
+/**
+ * @param {number} from
+ * @param {number} to
+ * @returns {number}
+ */
+function computeDiffPercent(from, to) {
+    if (from === to) {
+        return 0;
+    }
+
+    return Number(((from - to) / to * -100).toFixed(2));
+}
+
+/**
+ * @param {number} percent
+ * @returns {string}
+ */
+function formatDiffPercent(percent) {
+    return percent > 0 ? `+${percent}% 📈` : percent < 0 ? `${percent}% 📉` : `${percent}%`;
+}
+
+export function main() {
+    let base = JSON.parse(process.env.BASE_DIST_FILES);
+    let pr = JSON.parse(process.env.PR_DIST_FILES);
+    let output = '<h1>📊 Dist files size difference</h1>\n\n';
+
+    const files = [...new Set([...Object.keys(pr), ...Object.keys(base)])].sort().reduce((acc, file) => {
+        const added = !base[file] && pr[file];
+        const removed = base[file] && !pr[file];
+        const diff_percent_size = removed ? -100 : (added ? 100 : (computeDiffPercent(base[file].size, pr[file].size)));
+        const diff_percent_size_gz = removed ? -100 : (added ? 100 : (computeDiffPercent(base[file].size_gz, pr[file].size_gz)));
+        const diff_percent_size_brotli = removed ? -100 : (added ? 100 : (computeDiffPercent(base[file].size_brotli, pr[file].size_brotli)));
+
+        if (diff_percent_size !== 0 && diff_percent_size_gz !== 0 && diff_percent_size_brotli !== 0) {
+            acc.set(file, {
+                state: added ? 'added' : (removed ? 'removed' : 'changed'),
+                diff_percent_size,
+                diff_percent_size_gz,
+                diff_percent_size_brotli
+            });
+        }
+
+        return acc;
+    }, new Map);
+
+    if (files.size === 0) {
+        output += 'ℹ️ No difference in dist files.\n';
+        return output;
+    }
+
+    output += 'Thanks for the PR! Here is the difference in size of the dist files between the base and the PR.\n';
+    output += 'Please review the changes and make sure they are expected.\n\n';
+    output += `<table>
+    <thead><tr><th>File</th><th>Diff (B)</th><th>Diff (%)</th></tr></thead>
+    <tbody>`;
+    for (const [file, details] of files.entries()) {
+        output += `<tr>
+        <td><code>${file}</code> ${details.state === 'added' ? '(new)' : (details.state === 'removed' ? '(deleted)' : '')}</td>
+        <td>
+            Size: <code>${formatBytes(base[file]?.size || 0)}</code> → <code>${formatBytes(pr[file]?.size || 0)}</code><br>
+            Gzip: <code>${formatBytes(base[file]?.size_gz || 0)}</code> → <code>${formatBytes(pr[file]?.size_gz || 0)}</code><br>
+            Brotli: <code>${formatBytes(base[file]?.size_brotli || 0)}</code> → <code>${formatBytes(pr[file]?.size_brotli || 0)}</code>
+        </td>
+        <td align="right">
+            Size: <b>${formatDiffPercent(details.diff_percent_size)}</b><br>
+            Gzip: <b>${formatDiffPercent(details.diff_percent_size_gz)}</b><br>
+            Brotli: <b>${formatDiffPercent(details.diff_percent_size_brotli)}</b>
+        </td>
+    </tr>
+    `;
+    }
+    output += `</tbody>
+</table>
+`;
+
+    return output;
+}
+
+if (!process.env.CI) {
+    console.log(main());
+}

.github/workflows/dist-files-size-diff.yaml

@@ -0,0 +1,78 @@
+name: Dist Files Size Diff
+
+on:
+  pull_request:
+    paths:
+      - 'src/*/**'
+      - '!src/*/doc/**'
+      - '.github/**'
+
+jobs:
+    dist-files-size-diff:
+        runs-on: ubuntu-latest
+        permissions:
+          pull-requests: write # for marocchino/sticky-pull-request-comment@v2
+        steps:
+          - name: Configure git
+            run: |
+              git config --global user.email ""
+              git config --global user.name "github-action[bot]"
+              
+          - uses: marocchino/sticky-pull-request-comment@v2
+            with:
+              message: |
+                ⏳ The dist files size difference is being calculated...
+
+          - uses: actions/checkout@v4
+            with:
+              ref: ${{ github.base_ref }}
+
+          - name: Get dist files size (from base branch)
+            id: base-dist-files
+            run: |
+              set -e
+              
+              FILES=$(find src -mindepth 2 -path '*/assets/dist/*' \( -name "*.js" -o -name "*.css" \) -not \( -path '*/tests/*' -o -path '*/public/*' -o -path '*/vendor/*' \) | sort | while read -r file; do
+                  echo "{\"$file\": {\"size\": $(wc -c < "$file"), \"size_gz\": $(gzip -c "$file" | wc -c), \"size_brotli\": $(brotli -c "$file" | wc -c)}}"
+              done | jq -s 'add' -c)
+              
+              echo "files=$FILES" >> $GITHUB_OUTPUT
+
+          - uses: actions/checkout@v4
+
+          - name: Get dist files size (from pull request)
+            id: pr-dist-files
+            run: |
+              set -e
+              
+              FILES=$(find src -mindepth 2 -path '*/assets/dist/*' \( -name "*.js" -o -name "*.css" \) -not \( -path '*/tests/*' -o -path '*/public/*' -o -path '*/vendor/*' \) | sort | while read -r file; do
+                  echo "{\"$file\": {\"size\": $(wc -c < "$file"), \"size_gz\": $(gzip -c "$file" | wc -c), \"size_brotli\": $(brotli -c "$file" | wc -c)}}"
+              done | jq -s 'add' -c)
+              
+              echo "files=$FILES" >> $GITHUB_OUTPUT
+
+          - name: Generate the diff
+            id: diff
+            uses: actions/github-script@v7
+            env:
+                BASE_DIST_FILES: ${{ steps.base-dist-files.outputs.files }}
+                PR_DIST_FILES: ${{ steps.pr-dist-files.outputs.files }}
+            with:
+              result-encoding: string
+              script: |
+                const { main } = await import('${{ github.workspace }}/.github/generate-dist-files-size-diff.mjs')
+                
+                return await main()
+                
+          - name: Comment on the pull request (if any failure)
+            if: ${{ failure() }}
+            uses: marocchino/sticky-pull-request-comment@v2
+            with:
+              message: |
+                ❌ The dist files size difference could not be calculated. Please check the logs for more details.
+                
+          - name: Comment on the pull request (if success)
+            if: ${{ always() && steps.diff.conclusion == 'success' }}
+            uses: marocchino/sticky-pull-request-comment@v2
+            with:
+              message: ${{ steps.diff.outputs.result }}