only if dir exists

src/fs.zig

@@ -1100,7 +1100,7 @@ pub const PathName = struct {
         }
 
         if (comptime Environment.allow_assert) {
-            std.debug.assert(!strings.includes(self.base, "/"));
+            if (self.dir.len > 0) std.debug.assert(!strings.includes(self.base, "/"));
         }
 
         // /bar/foo.js -> foo

src/string_immutable.zig

@@ -224,6 +224,16 @@ pub fn indexOfSigned(self: string, str: string) i32 {
 }
 
 pub inline fn lastIndexOfChar(self: string, char: u8) ?usize {
+    if (comptime Environment.isLinux) {
+        const memrchr = struct {
+            pub extern fn memrchr(ptr: [*]const u8, val: c_int, len: usize) ?[*]const u8;
+        }.memrchr;
+        const start = memrchr(self.ptr, char, self.len) orelse return null;
+        const i = @ptrToInt(start) - @ptrToInt(self.ptr);
+        std.debug.assert(i < self.len);
+        return @intCast(usize, i);
+    }
+
     return std.mem.lastIndexOfScalar(u8, self, char);
 }
 

test/bundler/esbuild/default.test.ts

@@ -5953,9 +5953,9 @@ describe("bundler", () => {
         'Could not resolve: "@scope/pkg4". Maybe you need to "bun install"?',
         'Could not resolve: "@scope/pkg5/foo". Maybe you need to "bun install"?',
         'Could not resolve: "@abs-path/pkg6". Maybe you need to "bun install"?',
-        'Could not resolve: "@abs-path/pkg6/foo". Maybe you need to "bun install"?',
+        'Could not resolve: "@abs-path/pkg7/foo". Maybe you need to "bun install"?',
         'Could not resolve: "@scope-only/pkg8". Maybe you need to "bun install"?',
-        'Could not resolve: "slash/" Maybe. you need to "bun install"?',
+        'Could not resolve: "slash/". Maybe you need to "bun install"?',
         'Could not resolve: "pkg3". Maybe you need to "bun install"?',
       ],
     },