Fix wildcard exports extensionless resolution in bundler mode

src/compiler/moduleNameResolver.ts

@@ -2804,7 +2804,23 @@ function getLoadModuleFromTargetExportOrImport(extensions: Extensions, state: Mo
             const finalPath = toAbsolutePath(pattern ? resolvedTarget.replace(/\*/g, subpath) : resolvedTarget + subpath);
             const inputLink = tryLoadInputFileForPath(finalPath, subpath, combinePaths(scope.packageDirectory, "package.json"), isImports);
             if (inputLink) return inputLink;
-            return toSearchResult(withPackageId(scope, loadFileNameFromPackageJsonField(extensions, finalPath, target, /*onlyRecordFailures*/ false, state), state));
+            // First try the standard package.json field resolution
+            const fromPkgJsonField = loadFileNameFromPackageJsonField(extensions, finalPath, target, /*onlyRecordFailures*/ false, state);
+            if (fromPkgJsonField) {
+                return toSearchResult(withPackageId(scope, fromPkgJsonField, state));
+            }
+            // For extensionless paths in bundler mode (non-ESM), try adding extensions (e.g., ./foo -> ./foo.ts)
+            // This handles wildcard exports like "./*": "./src/*" where the resolved path has no extension.
+            if (!(state.features & NodeResolutionFeatures.EsmMode)) {
+                const filename = getBaseFileName(finalPath);
+                if (!filename.includes(".")) {
+                    const fromFile = loadModuleFromFile(extensions, finalPath, /*onlyRecordFailures*/ false, state);
+                    if (fromFile) {
+                        return toSearchResult(withPackageId(scope, fromFile, state));
+                    }
+                }
+            }
+            return toSearchResult(/*value*/ undefined);
         }
         else if (typeof target === "object" && target !== null) { // eslint-disable-line no-restricted-syntax
             if (!Array.isArray(target)) {

tests/baselines/reference/bundlerWildcardExportsExtensionResolution.symbols

@@ -0,0 +1,37 @@
+//// [tests/cases/compiler/bundlerWildcardExportsExtensionResolution.ts] ////
+
+=== /node_modules/@repo/library/src/utils.ts ===
+export function greet(): string {
+>greet : Symbol(greet, Decl(utils.ts, 0, 0))
+
+    return "hello";
+}
+
+=== /node_modules/@repo/library/src/component.tsx ===
+export const Component = () => null;
+>Component : Symbol(Component, Decl(component.tsx, 0, 12))
+
+=== /node_modules/@repo/library/src/deep/nested/module.ts ===
+export const deep = true;
+>deep : Symbol(deep, Decl(module.ts, 0, 12))
+
+=== /app.ts ===
+// These imports should all resolve successfully in bundler mode
+import { greet } from "@repo/library/utils";
+>greet : Symbol(greet, Decl(app.ts, 1, 8))
+
+import { Component } from "@repo/library/component";
+>Component : Symbol(Component, Decl(app.ts, 2, 8))
+
+import { deep } from "@repo/library/deep/nested/module";
+>deep : Symbol(deep, Decl(app.ts, 3, 8))
+
+greet();
+>greet : Symbol(greet, Decl(app.ts, 1, 8))
+
+Component;
+>Component : Symbol(Component, Decl(app.ts, 2, 8))
+
+deep;
+>deep : Symbol(deep, Decl(app.ts, 3, 8))
+

tests/baselines/reference/bundlerWildcardExportsExtensionResolution.trace.json

@@ -0,0 +1,44 @@
+[
+    "File '/node_modules/@repo/library/src/package.json' does not exist.",
+    "Found 'package.json' at '/node_modules/@repo/library/package.json'.",
+    "File '/node_modules/@repo/library/src/package.json' does not exist according to earlier cached lookups.",
+    "File '/node_modules/@repo/library/package.json' exists according to earlier cached lookups.",
+    "File '/node_modules/@repo/library/src/deep/nested/package.json' does not exist.",
+    "File '/node_modules/@repo/library/src/deep/package.json' does not exist.",
+    "File '/node_modules/@repo/library/src/package.json' does not exist according to earlier cached lookups.",
+    "File '/node_modules/@repo/library/package.json' exists according to earlier cached lookups.",
+    "======== Resolving module '@repo/library/utils' from '/app.ts'. ========",
+    "Explicitly specified module resolution kind: 'Bundler'.",
+    "Resolving in CJS mode with conditions 'import', 'types'.",
+    "File '/package.json' does not exist.",
+    "Loading module '@repo/library/utils' from 'node_modules' folder, target file types: TypeScript, JavaScript, Declaration, JSON.",
+    "Searching all ancestor node_modules directories for preferred extensions: TypeScript, Declaration.",
+    "File '/node_modules/@repo/library/package.json' exists according to earlier cached lookups.",
+    "Using 'exports' subpath './*' with target './src/utils'.",
+    "File '/node_modules/@repo/library/src/utils.ts' exists - use it as a name resolution result.",
+    "Resolving real path for '/node_modules/@repo/library/src/utils.ts', result '/node_modules/@repo/library/src/utils.ts'.",
+    "======== Module name '@repo/library/utils' was successfully resolved to '/node_modules/@repo/library/src/utils.ts'. ========",
+    "======== Resolving module '@repo/library/component' from '/app.ts'. ========",
+    "Explicitly specified module resolution kind: 'Bundler'.",
+    "Resolving in CJS mode with conditions 'import', 'types'.",
+    "File '/package.json' does not exist according to earlier cached lookups.",
+    "Loading module '@repo/library/component' from 'node_modules' folder, target file types: TypeScript, JavaScript, Declaration, JSON.",
+    "Searching all ancestor node_modules directories for preferred extensions: TypeScript, Declaration.",
+    "File '/node_modules/@repo/library/package.json' exists according to earlier cached lookups.",
+    "Using 'exports' subpath './*' with target './src/component'.",
+    "File '/node_modules/@repo/library/src/component.ts' does not exist.",
+    "File '/node_modules/@repo/library/src/component.tsx' exists - use it as a name resolution result.",
+    "Resolving real path for '/node_modules/@repo/library/src/component.tsx', result '/node_modules/@repo/library/src/component.tsx'.",
+    "======== Module name '@repo/library/component' was successfully resolved to '/node_modules/@repo/library/src/component.tsx'. ========",
+    "======== Resolving module '@repo/library/deep/nested/module' from '/app.ts'. ========",
+    "Explicitly specified module resolution kind: 'Bundler'.",
+    "Resolving in CJS mode with conditions 'import', 'types'.",
+    "File '/package.json' does not exist according to earlier cached lookups.",
+    "Loading module '@repo/library/deep/nested/module' from 'node_modules' folder, target file types: TypeScript, JavaScript, Declaration, JSON.",
+    "Searching all ancestor node_modules directories for preferred extensions: TypeScript, Declaration.",
+    "File '/node_modules/@repo/library/package.json' exists according to earlier cached lookups.",
+    "Using 'exports' subpath './*' with target './src/deep/nested/module'.",
+    "File '/node_modules/@repo/library/src/deep/nested/module.ts' exists - use it as a name resolution result.",
+    "Resolving real path for '/node_modules/@repo/library/src/deep/nested/module.ts', result '/node_modules/@repo/library/src/deep/nested/module.ts'.",
+    "======== Module name '@repo/library/deep/nested/module' was successfully resolved to '/node_modules/@repo/library/src/deep/nested/module.ts'. ========"
+]

tests/baselines/reference/bundlerWildcardExportsExtensionResolution.types

@@ -0,0 +1,54 @@
+//// [tests/cases/compiler/bundlerWildcardExportsExtensionResolution.ts] ////
+
+=== /node_modules/@repo/library/src/utils.ts ===
+export function greet(): string {
+>greet : () => string
+>      : ^^^^^^      
+
+    return "hello";
+>"hello" : "hello"
+>        : ^^^^^^^
+}
+
+=== /node_modules/@repo/library/src/component.tsx ===
+export const Component = () => null;
+>Component : () => any
+>          : ^^^^^^^^^
+>() => null : () => any
+>           : ^^^^^^^^^
+
+=== /node_modules/@repo/library/src/deep/nested/module.ts ===
+export const deep = true;
+>deep : true
+>     : ^^^^
+>true : true
+>     : ^^^^
+
+=== /app.ts ===
+// These imports should all resolve successfully in bundler mode
+import { greet } from "@repo/library/utils";
+>greet : () => string
+>      : ^^^^^^      
+
+import { Component } from "@repo/library/component";
+>Component : () => any
+>          : ^^^^^^^^^
+
+import { deep } from "@repo/library/deep/nested/module";
+>deep : true
+>     : ^^^^
+
+greet();
+>greet() : string
+>        : ^^^^^^
+>greet : () => string
+>      : ^^^^^^      
+
+Component;
+>Component : () => any
+>          : ^^^^^^^^^
+
+deep;
+>deep : true
+>     : ^^^^
+

tests/baselines/reference/node16WildcardExportsRequiresExtension.errors.txt

@@ -0,0 +1,30 @@
+/app.ts(2,23): error TS2307: Cannot find module '@repo/library/utils' or its corresponding type declarations.
+
+
+==== /node_modules/@repo/library/package.json (0 errors) ====
+    {
+        "name": "@repo/library",
+        "type": "module",
+        "exports": {
+            "./*": "./src/*"
+        }
+    }
+
+==== /node_modules/@repo/library/src/utils.ts (0 errors) ====
+    export function greet(): string {
+        return "hello";
+    }
+
+==== /package.json (0 errors) ====
+    {
+        "type": "module"
+    }
+
+==== /app.ts (1 errors) ====
+    // This import should FAIL in node16 mode - extensionless imports not supported
+    import { greet } from "@repo/library/utils";
+                          ~~~~~~~~~~~~~~~~~~~~~
+!!! error TS2307: Cannot find module '@repo/library/utils' or its corresponding type declarations.
+
+    greet();
+

tests/baselines/reference/node16WildcardExportsRequiresExtension.symbols

@@ -0,0 +1,17 @@
+//// [tests/cases/compiler/node16WildcardExportsRequiresExtension.ts] ////
+
+=== /node_modules/@repo/library/src/utils.ts ===
+export function greet(): string {
+>greet : Symbol(greet, Decl(utils.ts, 0, 0))
+
+    return "hello";
+}
+
+=== /app.ts ===
+// This import should FAIL in node16 mode - extensionless imports not supported
+import { greet } from "@repo/library/utils";
+>greet : Symbol(greet, Decl(app.ts, 1, 8))
+
+greet();
+>greet : Symbol(greet, Decl(app.ts, 1, 8))
+