### What does this PR do?
Fixes printing `import.meta.url` and others with `--bytecode`. Fixes
#14954.
Fixes printing `__toESM` when output module format is CJS and input
module format is ESM.
The key change is that `__toESM`'s `isNodeMode` parameter now depends on
the **input module type** (whether the importing file uses ESM syntax
like `import`/`export`) rather than the output format. This matches
Node.js ESM behavior where importing CommonJS from `.mjs` files always
wraps the entire `module.exports` object as the default export, ignoring
`__esModule` markers.
### How did you verify your code works?
Added comprehensive test suite in `test/bundler/bundler_cjs.test.ts`
with **23 tests** covering:
#### Core Behaviors:
- ✅ Files using `import` syntax always get `isNodeMode=1`, which
**ignores `__esModule`** markers and wraps the entire CJS module as
default
- ✅ This matches Node.js ESM semantics for importing CJS from `.mjs`
files
- ✅ Different CJS export patterns (`exports.x`, `module.exports = ...`,
functions, primitives)
- ✅ Named, default, and namespace (`import *`) imports
- ✅ Different targets (node, browser, bun) - all behave the same
- ✅ Different output formats (esm, cjs) - format doesn't affect the
behavior
- ✅ `.mjs` files re-exporting from `.cjs`
- ✅ Deep re-export chains
- ✅ Edge cases (non-boolean `__esModule`, `__esModule=false`, etc.)
#### Test Results:
- **With this PR's changes**: All 23 tests pass ✅
- **Without this PR (system bun)**: 22 pass, 1 fails (the one testing
that `__esModule` is ignored with import syntax + CJS format)
The failing test with system bun demonstrates the bug being fixed:
currently, format=cjs with import syntax still respects `__esModule`,
but it should ignore it (matching Node.js behavior).
---------
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
Co-authored-by: Claude Bot <claude-bot@bun.sh>
