Add utility function to join paths (#3060)

src/utils/joinPath.test.ts

@@ -0,0 +1,23 @@
+import { describe, expect, it } from "vitest";
+import { joinPath } from "./joinPath";
+
+describe("joinPath", () => {
+  it("returns an empty string when no paths are provided", () => {
+    expect(joinPath()).toBe("");
+  });
+
+  it("joins paths", () => {
+    expect(joinPath("foo", "bar", "baz")).toBe("foo/bar/baz");
+    expect(joinPath("foo", "/bar", "baz")).toBe("foo/bar/baz");
+    expect(joinPath("foo", "bar/", "baz")).toBe("foo/bar/baz");
+    expect(joinPath("foo", "/bar/", "baz")).toBe("foo/bar/baz");
+  });
+
+  it("joins paths with leading slashes", () => {
+    expect(joinPath("/foo", "bar", "baz")).toBe("/foo/bar/baz");
+  });
+
+  it("joins paths with trailing slashes", () => {
+    expect(joinPath("foo", "bar", "baz/")).toBe("foo/bar/baz/");
+  });
+});

src/utils/joinPath.ts

@@ -0,0 +1,22 @@
+const PATH_SEPARATOR = "/";
+
+export function joinPath(...paths: string[]) {
+  const normalizedPaths = paths.map((path, index) => {
+    const isFirst = index === 0;
+    const isLast = index === paths.length - 1;
+
+    // Strip out any leading slashes from the path.
+    if (!isFirst && path.startsWith(PATH_SEPARATOR)) {
+      path = path.slice(1);
+    }
+
+    // Strip out any trailing slashes from the path.
+    if (!isLast && path.endsWith(PATH_SEPARATOR)) {
+      path = path.slice(0, -1);
+    }
+
+    return path;
+  }, []);
+
+  return normalizedPaths.join(PATH_SEPARATOR);
+}