From 991a8316f8ed81b9bb9e4a31d3826c238d742a3e Mon Sep 17 00:00:00 2001
From: David Reed <reedswork@proton.me>
Date: Sun, 5 Feb 2023 19:57:19 -0500
Subject: [PATCH] Make dynamic imports relative to the importing script

---
 src/rewrite/index.js          | 14 ++++++++++++++
 src/rewrite/rewrite.script.js |  4 +++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/src/rewrite/index.js b/src/rewrite/index.js
index 4f1986e..4354a23 100644
--- a/src/rewrite/index.js
+++ b/src/rewrite/index.js
@@ -51,6 +51,7 @@ class Ultraviolet {
         //this.urlRegex = /^(#|about:|data:|mailto:|javascript:)/;
         this.urlRegex = /^(#|about:|data:|mailto:)/;
         this.rewriteUrl = options.rewriteUrl || this.rewriteUrl;
+        this.rewriteImport = options.rewriteImport || this.rewriteImport;
         this.sourceUrl = options.sourceUrl || this.sourceUrl;
         this.encodeUrl = options.encodeUrl || this.encodeUrl;
         this.decodeUrl = options.decodeUrl || this.decodeUrl;
@@ -97,6 +98,19 @@ class Ultraviolet {
             setCookie,
         };
     }
+    /**
+     *
+     * @param {string} str Script being imported
+     * @param {string} src Script that is importing
+     * @param {*} meta
+     */
+    rewriteImport(str, src, meta = this.meta) {
+        // use importiing script as the base
+        return this.rewriteUrl(str, {
+            ...meta,
+            base: src,
+        });
+    }
     rewriteUrl(str, meta = this.meta) {
         str = new String(str).trim();
         if (!str || this.urlRegex.test(str)) return str;
diff --git a/src/rewrite/rewrite.script.js b/src/rewrite/rewrite.script.js
index 5b83d2f..a9d1dde 100644
--- a/src/rewrite/rewrite.script.js
+++ b/src/rewrite/rewrite.script.js
@@ -263,7 +263,9 @@ function dynamicImport(ctx) {
     js.on(Syntax.ImportExpression, (node, data, type) => {
         if (type !== 'rewrite') return false;
         data.changes.push({
-            node: '__uv.rewriteUrl(',
+            // pass script URL to dynamicImport
+            // import() is always relative to script URL
+            node: `__uv.rewriteImport(${JSON.stringify(ctx.meta.url)},`,
             start: node.source.start,
             end: node.source.start,
         });