import_map_resolver.js

@@ -0,0 +1,83 @@
+/**
+ * Resolves a module specifier against an import map
+ * @param {string} specifier - The module specifier to resolve (bare specifier or absolute URL)
+ * @param {Object} importMap - The import map object containing imports and scopes
+ * @param {string} baseURL - The base URL for context (especially for scopes)
+ * @returns {string} The resolved URL
+ */
+export default function resolveImportMap(specifier, importMap, baseURL) {
+
+    // Check for exact matches first (most common case for bare specifiers)
+    const lookup = importMap.imports[specifier];
+    if (lookup) { return lookup; }
+    
+    const Scanner =(obj)=>
+    {
+        // Check for path prefix matches (longest first)
+        const keys = Object.keys(obj)
+        .filter(key => key.endsWith('/'))
+        .sort((a, b) => b.length - a.length);
+        for (const key of keys)
+        {
+            if (specifier.startsWith(key))
+            {
+                const remainder = specifier.slice(key.length);
+                return obj[key] + remainder;
+            }
+        }
+    }
+
+    const scan = Scanner(importMap.imports);
+    if (scan) {return scan}
+    
+    // Handle scopes if available
+    if (importMap.scopes) {
+        const scopeKeys = Object.keys(importMap.scopes).sort((a, b) => b.length - a.length);
+        for (const scopeKey of scopeKeys)
+        {
+            if (specifier.startsWith(scopeKey))
+            {
+                const scopeImports = importMap.scopes[scopeKey];
+                const scan = Scanner(scopeImports);
+                if (scan) {return scan}
+            }
+        }
+    }
+
+    return specifier;
+  }
+  
+  // Example usage for bare specifiers:
+  function demonstrateOptimizedResolver() {
+    const importMap = {
+      "imports": {
+        "lodash": "https://cdn.skypack.dev/lodash",
+        "react": "https://cdn.skypack.dev/react",
+        "lib/": "/node_modules/lib/",
+        "components/": "/components/"
+      },
+      "scopes": {
+        "/admin/": {
+          "components/": "/admin-components/",
+          "admin-utils": "scoped!/js/admin-utils.js"
+        }
+      }
+    };
+    
+    // Examples with bare specifiers
+    console.log("Resolving 'lodash':", resolveImportMap("lodash", importMap, "https://example.com/admin/dashboard/"));
+    console.log("Resolving 'components/button':", resolveImportMap("components/button", importMap, "https://example.com/admin/dashboard/"));
+    
+    // Example with scope
+    console.log("Resolving 'admin-utils':", 
+      resolveImportMap("admin-utils", importMap, "https://example.com/admin/dashboard/"));
+
+    console.log("Resolving '/admin/admin-utils':", 
+        resolveImportMap("admin-utils", importMap, "https://example.com/admin/dashboard/"));
+      
+    // Example with URL
+    console.log("Resolving 'https://example.com/external.js':", 
+      resolveImportMap("https://example.com/external.js", importMap, "https://example.com/admin/dashboard/"));
+  }
+  
+  demonstrateOptimizedResolver();

mod.ts

@@ -61,8 +61,8 @@ export default async function(directory, buildOptions={}, importMap)
     jsxImportSource: "react",
     ...buildOptions,
     plugins: [
-      resolvePlugin(directory),
       Mapper.importmapPlugin(importMap) as ESBuild.Plugin,
+      resolvePlugin(directory),
       ...buildOptions.plugins||[]
     ]
   };

what/entry.ts

@@ -1,9 +1,10 @@
-import Message from "./include.ts";
+import React from "react";
+import Message from "./include_a.ts";
 
 type Person = {name:string, age:number};
 
 const me:Person = {name:"seth", age:41};
 
-console.log(Message);
+console.log(Message, React);
 
 export default me;

what/include.ts

@@ -1,5 +0,0 @@
-import * as React from "react";
-
-console.log(React);
-
-export default "HELLO";

what/include_a.ts

@@ -0,0 +1,6 @@
+import * as B from "./include_b.ts";
+import * as React from "react";
+
+console.log(React, B);
+
+export default "HELLO";

what/include_b.ts

@@ -0,0 +1 @@
+export default {};

what/index.ts

@@ -4,10 +4,11 @@ const {outputFiles} = await Bundle(
     import.meta.resolve('./'),
 
     // ESBuild configuration (entry points are relative to "directory"):
-    {entryPoints:["./entry.ts"]},
+    {entryPoints:["entry"]},
 
     // import map (if omitted, will scan for a deno configuration within "directory" and use that)
     {"imports": {
+        "entry": "./entry.ts",
         "react": "https://esm.sh/preact@10.22.0/compat",
         "react/": "https://esm.sh/preact@10.22.0/compat/"
     }}
@@ -15,5 +16,5 @@ const {outputFiles} = await Bundle(
 
 for(const item of outputFiles){
     // do something with the output...
-    console.log(item.text);
+    console.log(item.text.substring(0, 200));
 }