Revamp snapshot tests (vercel#2351)

* Disable HMR for snapshot tests

The only effect is that we don't emit source maps for the individual chunk items, reducing the total number of output files considerably.

* Extract snapshot tests into separate crate

* Strip annoying file hash fingerprints

* Reduce deps

* Update old references to turbopack/test/snapshot

* Move node_modules out of snapshot dir

* Only un-fingerprint EcmascriptChunkSourceMapAssetVc source maps

* Fix gitignore

* Remove dbg

* TAPLO

* Apply suggestions from code review

Co-authored-by: Alex Kirszenberg <[email protected]>

* Use eprintln

Co-authored-by: Alex Kirszenberg <[email protected]>

.gitattributes

@@ -1 +1 @@
-crates/turbopack/tests/snapshot/*/output/** linguist-generated=true
+crates/turbopack-tests/tests/snapshot/**/output/** linguist-generated=true

.gitignore

@@ -19,9 +19,6 @@ graph*.html
 .pnp.*
 .yarn/*
 
-# include everything in the snapshots dir
-!crates/turbopack/tests/snapshot/**
-
 # generated by cargo xtask publish
 packages/node-module-trace/npm
 artifacts

.prettierignore

@@ -4,7 +4,7 @@ dist/
 node_modules/
 target/
 
-/crates/turbopack/tests/snapshot/**/output/
+/crates/turbopack-tests/tests/snapshot/**/output/
 /examples/with-svelte
 
 pnpm-lock.yaml

Cargo.toml

@@ -27,6 +27,7 @@ members = [
   "crates/turbopack-static",
   "crates/turbopack-swc-utils",
   "crates/turbopack",
+  "crates/turbopack-tests",
   "xtask",
 ]
 

crates/turbo-tasks-build/src/lib.rs

@@ -158,10 +158,10 @@ pub fn generate_register() {
     }
 }
 
-pub fn rerun_if_glob(globs: &str) {
+pub fn rerun_if_glob(globs: &str, root: &str) {
     let cwd = env::current_dir().unwrap();
     let globs = cwd.join(globs);
-    let mut seen = HashSet::from([cwd.as_path().to_owned()]);
+    let mut seen = HashSet::from([cwd.join(root)]);
     for entry in glob(globs.to_str().unwrap()).unwrap() {
         let path = entry.unwrap();
         for ancestor in path.ancestors() {

crates/turbopack-ecmascript/Cargo.toml

@@ -59,7 +59,6 @@ version = "0.4"
 
 [dev-dependencies]
 criterion = { version = "0.3.5", features = ["async_tokio"] }
-difference = "2.0"
 rstest = "0.12.0"
 turbo-tasks-memory = { path = "../turbo-tasks-memory" }
 turbo-tasks-testing = { path = "../turbo-tasks-testing" }

crates/turbopack-ecmascript/src/chunk/mod.rs

@@ -1,6 +1,6 @@
 pub mod loader;
 pub(crate) mod optimize;
-pub(crate) mod source_map;
+pub mod source_map;
 
 use std::{fmt::Write as _, slice::Iter};
 

crates/turbopack-tests/Cargo.toml

@@ -0,0 +1,30 @@
+[package]
+name = "turbopack-tests"
+version = "0.1.0"
+description = "TBD"
+license = "MPL-2.0"
+edition = "2021"
+autobenches = false
+
+# don't publish this crate
+publish = false
+
+[dev-dependencies]
+anyhow = "1.0.47"
+once_cell = "1.13.0"
+serde = "1.0.136"
+serde_json = "1.0.85"
+similar = "2.2.0"
+test-generator = "0.3.0"
+tokio = "1.11.0"
+turbo-tasks = { path = "../turbo-tasks" }
+turbo-tasks-env = { path = "../turbo-tasks-env" }
+turbo-tasks-fs = { path = "../turbo-tasks-fs" }
+turbo-tasks-memory = { path = "../turbo-tasks-memory" }
+turbopack = { path = "../turbopack" }
+turbopack-core = { path = "../turbopack-core" }
+turbopack-ecmascript = { path = "../turbopack-ecmascript" }
+turbopack-env = { path = "../turbopack-env" }
+
+[build-dependencies]
+turbo-tasks-build = { path = "../turbo-tasks-build" }

crates/turbopack-tests/README.md

@@ -0,0 +1,26 @@
+# turbopack-tests
+
+An extracted create to perform snapshot tests on turbopack.
+
+## Testing
+
+It's possible to only run the snapshot tests using [nextest][]'s filter
+expressions:
+
+```bash
+cargo nextest run -E 'test(snapshot)'
+```
+
+The filter supports any substring, and only test names which contain
+that substring will run.
+
+## Updating Snapshot
+
+If you've made a change that requires many snapshot updates, you can
+automatically update all outputs using the `UPDATE` command line env:
+
+```bash
+UPDATE=1 cargo nextest run -E 'test(snapshot)'
+```
+
+[nextest]: https://nexte.st/

crates/turbopack-tests/build.rs

@@ -0,0 +1,9 @@
+use turbo_tasks_build::{generate_register, rerun_if_glob};
+
+fn main() {
+    generate_register();
+    // The test/snapshot crate need to be rebuilt if any snapshots are added.
+    // Unfortunately, we can't have the build.rs file operate differently on
+    // each file, so the entire turbopack crate needs to be rebuilt.
+    rerun_if_glob("tests/snapshot/*/*", "test/snapshot");
+}

crates/turbopack-tests/tests/.gitignore

@@ -0,0 +1,4 @@
+/node_modules
+# include everything in the snapshots dir
+!snapshot/**
+