[bun.js] Implement `import.meta.resolve`

1 files changed, 106 insertions, 0 deletions

diff --git a/integration/bunjs-only-snippets/resolve.test.js b/integration/bunjs-only-snippets/resolve.test.js
new file mode 100644
index 000000000..d5d14dfef
--- /dev/null
+++ b/integration/bunjs-only-snippets/resolve.test.js
@@ -0,0 +1,106 @@
+import { it, expect } from "bun:test";
+import { mkdirSync, writeFileSync } from "fs";
+import { join } from "path";
+
+it("import.meta.resolve", async () => {
+  expect(await import.meta.resolve("./resolve.test.js")).toBe(import.meta.url);
+
+  expect(await import.meta.resolve("./resolve.test.js", import.meta.url)).toBe(
+    import.meta.url
+  );
+
+  expect(
+    // optional second param can be any path, including a dir
+    await import.meta.resolve(
+      "./bunjs-only-snippets/resolve.test.js",
+      join(import.meta.url, "../")
+    )
+  ).toBe(import.meta.url);
+
+  // can be a package path
+  expect((await import.meta.resolve("react", import.meta.url)).length > 0).toBe(
+    true
+  );
+
+  // file extensions are optional
+  expect(await import.meta.resolve("./resolve.test")).toBe(import.meta.url);
+
+  // works with tsconfig.json "paths"
+  expect(await import.meta.resolve("foo/bar")).toBe(
+    join(import.meta.url, "../baz.js")
+  );
+
+  // works with package.json "exports"
+  writePackageJSONExportsFixture();
+  expect(await import.meta.resolve("package-json-exports/baz")).toBe(
+    join(import.meta.url, "../node_modules/package-json-exports/foo/bar.js")
+  );
+
+  expect(await import.meta.resolve("./resolve-typescript-file.tsx")).toBe(
+    join(import.meta.url, "../resolve-typescript-file.tsx")
+  );
+  expect(await import.meta.resolve("./resolve-typescript-file.js")).toBe(
+    join(import.meta.url, "../resolve-typescript-file.tsx")
+  );
+
+  // works with typescript edgecases like:
+  // - If the file ends with .js and it doesn't exist, try again with .ts and .tsx
+  expect(await import.meta.resolve("./resolve-typescript-file.js")).toBe(
+    join(import.meta.url, "../resolve-typescript-file.tsx")
+  );
+  expect(await import.meta.resolve("./resolve-typescript-file.tsx")).toBe(
+    join(import.meta.url, "../resolve-typescript-file.tsx")
+  );
+
+  try {
+    await import.meta.resolve("THIS FILE DOESNT EXIST");
+    throw new Error("Test failed");
+  } catch (exception) {
+    expect(exception instanceof ResolveError).toBe(true);
+    expect(exception.referrer).toBe(import.meta.url);
+    expect(exception.name).toBe("ResolveError");
+  }
+});
+
+// the slightly lower level API, which doesn't prefill the second param
+// and expects a directory instead of a filepath
+it("Bun.resolve", async () => {
+  expect(await Bun.resolve("./resolve.test.js", import.meta.dir)).toBe(
+    import.meta.url
+  );
+});
+
+// synchronous
+it("Bun.resolveSync", () => {
+  expect(Bun.resolveSync("./resolve.test.js", import.meta.dir)).toBe(
+    import.meta.url
+  );
+});
+
+function writePackageJSONExportsFixture() {
+  try {
+    mkdirSync(
+      join(import.meta.dir, "./node_modules/package-json-exports/foo"),
+      {
+        recursive: true,
+      }
+    );
+  } catch (exception) {}
+  writeFileSync(
+    join(import.meta.dir, "./node_modules/package-json-exports/foo/bar.js"),
+    "export const bar = 1;"
+  );
+  writeFileSync(
+    join(import.meta.dir, "./node_modules/package-json-exports/package.json"),
+    JSON.stringify(
+      {
+        name: "package-json-exports",
+        exports: {
+          "./baz": "./foo/bar.js",
+        },
+      },
+      null,
+      2
+    )
+  );
+}