glob: scan a group that crosses a path separator with the matcher

bench/glob/scan.mjs

@@ -6,6 +6,12 @@ const normalPattern = "*.ts";
 const recursivePattern = "**/*.ts";
 const nodeModulesPattern = "**/node_modules/**/*.js";
 const multiLevelPattern = "node_modules/*/lib/*.js";
+const crossingGroupPattern = "{node_modules/*/lib,src}/*.js";
+// A name after the group: one lookup in each directory that the group ends at, as for the written-out patterns.
+const crossingGroupThenNamePattern = "{node_modules/*,src}/package.json";
+// A list joined into one group, longer than the 255 bytes that the matcher keeps a cache for.
+const joinedList = Array.from({ length: 40 }, (_, i) => `node_modules/${"abcdefghij"[i % 10]}*/lib/*${i}.js`);
+const joinedPattern = `{${joinedList.join(",")}}`;
 
 const benchFdir = false;
 const cwd = undefined;
@@ -137,6 +143,49 @@ group({ name: `sync multi-level pattern="${multiLevelPattern}"`, summary: true }
     });
 });
 
+group({ name: `sync crossing-group pattern="${crossingGroupPattern}"`, summary: true }, () => {
+  bench("fast-glob", () => {
+    const entries = fg.globSync([crossingGroupPattern], fgOpts);
+  });
+
+  if (Glob)
+    bench("Bun.Glob", () => {
+      const entries = [...new Glob(crossingGroupPattern).scanSync(bunOpts)];
+    });
+});
+
+group({ name: `sync crossing-group pattern="${crossingGroupThenNamePattern}"`, summary: true }, () => {
+  bench("fast-glob", () => {
+    const entries = fg.globSync([crossingGroupThenNamePattern], fgOpts);
+  });
+
+  if (Glob) {
+    bench("Bun.Glob", () => {
+      const entries = [...new Glob(crossingGroupThenNamePattern).scanSync(bunOpts)];
+    });
+    bench("Bun.Glob, one scan for each alternative", () => {
+      const entries = ["node_modules/*/package.json", "src/package.json"].flatMap(pattern => [
+        ...new Glob(pattern).scanSync(bunOpts),
+      ]);
+    });
+  }
+});
+
+group({ name: `sync ${joinedList.length} patterns joined into one group`, summary: true }, () => {
+  bench("fast-glob", () => {
+    const entries = fg.globSync(joinedList, fgOpts);
+  });
+
+  if (Glob) {
+    bench("Bun.Glob", () => {
+      const entries = [...new Glob(joinedPattern).scanSync(bunOpts)];
+    });
+    bench("Bun.Glob, one scan for each pattern", () => {
+      const entries = joinedList.flatMap(pattern => [...new Glob(pattern).scanSync(bunOpts)]);
+    });
+  }
+});
+
 await run({
   avg: true,
   colors: false,

docs/pm/workspaces.mdx

@@ -56,6 +56,8 @@ The `"workspaces"` key in the root `package.json` lists the subdirectories to tr
 
 A negative pattern removes what the globs match, wherever it is in the list. `!dir/**` removes `dir` and everything below it. A negative pattern does not remove a directory that is listed by its path. `bun run --filter` and `--workspaces` skip the excluded packages too.
 
+A `{a,b}` group is one pattern, and an alternative can contain a `/`. `"{apps/web,packages/*}"` takes `apps/web` and every package in `packages`. List a path that leaves the root, such as `"../shared"`, as its own entry.
+
 Each workspace has its own `package.json`. To reference another package in the monorepo, use a semver range or the workspace protocol (for example `workspace:*`) as the version in your `package.json`.
 
 ```json packages/pkg-a/package.json icon="file-json"

docs/runtime/glob.mdx

@@ -145,6 +145,8 @@ glob.match("d.ts"); // => false
 
 You can nest these patterns to any depth, and they can contain any of the other wildcards.
 
+An alternative can contain a `/`. `src/{a,b/c}/index.ts` matches `src/a/index.ts` and `src/b/c/index.ts`, and `scan()` lists both.
+
 ### `{1..3}` - Match a range of numbers or letters
 
 ```ts