test: add integration test for TypeScript declarations

Signed-off-by: Andrey <[email protected]>

Author: ankddev

.github/workflows/ci.yaml

@@ -470,6 +470,10 @@ jobs:
         run: make
         working-directory: ./test/javascript_prelude
 
+      - name: Test generated TypeScript declarations
+        run: make test
+        working-directory: ./test/typescript_declarations
+
       - name: Test export of hex tarball
         run: make test
         working-directory: ./test/hextarball

Makefile

@@ -24,6 +24,7 @@ test: ## Run the compiler unit tests
 	cd test/project_javascript && cargo run clean && cargo run check && cargo run test
 	cd test/project_deno && cargo run clean && cargo run check && cargo run test
 	cd test/hextarball && make test
+	cd test/typescript_declarations && make test
 	cd test/running_modules && make test
 	cd test/subdir_ffi && make
 
@@ -51,6 +52,14 @@ test-watch: ## Run compiler tests when files change
 export-hex-tarball-test: ## Run `gleam export hex-tarball` and verify it is created
 	cd test/hextarball && make test
 
+.PHONY: typescript-declarations-test
+typescript-declarations-test: ## Check that generated TypeScript declaration compile
+	cd test/typescript_declarations && make test
+
+.PHONY: typescript-declarations-test-watch
+typescript-declarations-test-watch: ## Check that generated TypeScript declaration compile when files change
+	watchexec "cd test/typescript_declarations && make test"
+
 .PHONY: benchmark
 benchmark: ## Run the benchmarks
 	cd benchmark/list && make

test/typescript_declarations/.gitignore

@@ -0,0 +1,4 @@
+*.beam
+*.ez
+/build
+erl_crash.dump

test/typescript_declarations/Makefile

@@ -0,0 +1,9 @@
+.PHONY: clean
+clean:
+	rm -rf build
+
+.PHONY: build
+test:
+	cargo run --quiet -- build
+	tsc ./build/dev/javascript/typescript_declarations/typescript_declarations.d.mts --noEmit --lib es2015
+

test/typescript_declarations/README.md

@@ -0,0 +1,4 @@
+# typescript_declarations
+
+Check that generated TypeScript declarartions are correct. This requires TypeScript installed and be in PATH.
+

test/typescript_declarations/gleam.toml

@@ -0,0 +1,10 @@
+name = "typescript_declarations"
+version = "1.0.0"
+target = "javascript"
+
+[javascript]
+typescript_declarations = true
+
+[dependencies]
+gleam_stdlib = ">= 0.44.0 and < 2.0.0"
+

test/typescript_declarations/manifest.toml

@@ -0,0 +1,9 @@
+# This file was generated by Gleam
+# You typically do not need to edit this file
+
+packages = [
+  { name = "gleam_stdlib", version = "0.62.1", build_tools = ["gleam"], requirements = [], otp_app = "gleam_stdlib", source = "hex", outer_checksum = "0080706D3A5A9A36C40C68481D1D231D243AF602E6D2A2BE67BA8F8F4DFF45EC" },
+]
+
+[requirements]
+gleam_stdlib = { version = ">= 0.44.0 and < 2.0.0" }

test/typescript_declarations/src/typescript_declarations.gleam

@@ -0,0 +1,20 @@
+//// Test TS declarartions
+
+/// Answer for all questions in the world
+pub const answer = 256
+
+pub type User {
+  // Registered user
+  User(name: String, email: String)
+  /// Unregistered guest
+  Guest
+}
+
+/// Get name of user. Returns "Guest" if user is guest
+pub fn get_name(user) {
+  case user {
+    User(name, ..) -> name
+    Guest -> "Guest"
+  }
+}
+