Handle the scenario where a package.json#browser field could be set t…

…o {'./some-path': false}

src/resolve-dependency.ts

@@ -128,7 +128,7 @@ interface PkgCfg {
   main: string | undefined;
   exports: PackageTarget;
   imports: { [key: string]: PackageTarget };
-  browser?: string | { [key: string]: string };
+  browser?: unknown;
 }
 
 async function getPkgCfg(
@@ -259,8 +259,21 @@ async function resolveRemappings(
 ): Promise<void> {
   if (job.conditions?.includes('browser')) {
     const { browser: pkgBrowser } = pkgCfg;
+    if (!pkgBrowser) {
+      return;
+    }
+    if (typeof pkgBrowser === 'string') {
+      return;
+    }
     if (typeof pkgBrowser === 'object') {
       for (const [key, value] of Object.entries(pkgBrowser)) {
+        if (typeof value !== 'string') {
+          /**
+           * `false` can be used to specify that a file is not meant to be included.
+           * Downstream processing is expected to handle this case, and it should remain in the mapping result
+           */
+          continue;
+        }
         if (!key.startsWith('./') || !value.startsWith('./')) {
           continue;
         }

test/unit/browser-remappings-false/.gitignore

@@ -0,0 +1,2 @@
+# include node_modules for testing
+!node_modules 

test/unit/browser-remappings-false/input.js

@@ -0,0 +1,2 @@
+require('pkg');
+

test/unit/browser-remappings-false/output.js

@@ -0,0 +1,7 @@
+[
+  "package.json",
+  "test/unit/browser-remappings-false/input.js",
+  "test/unit/browser-remappings-false/node_modules/pkg/browser.js",
+  "test/unit/browser-remappings-false/node_modules/pkg/index.js",
+  "test/unit/browser-remappings-false/node_modules/pkg/package.json"
+]

test/unit/browser-remappings-false/test-opts.json

@@ -0,0 +1,3 @@
+{
+  "conditions": ["browser"]
+}