Language Tests

https://coderide.dev

A collection of per-language test files used to exercise editor features: syntax highlighting, bracket matching, code folding, indentation, auto-completion, diagnostics, go-to-definition, find-references, and more.

Each file is written to cover a broad slice of its language's syntax and semantics (structs/classes, generics, enums, concurrency, error handling, unit tests, decorators, etc.) so you can verify the editor behaves well across real-world constructs.

Language matrix

Language	File / project	Run tests	Requirements
C	c/test.c	compile, then run	C compiler (C17)
Ruby	ruby/test.rb	ruby test.rb	Ruby ≥ 3.4
C++	cpp/test.cpp	compile, then run	C++ compiler (C++20)
Go	go/test.go	go run test.go	Go toolchain
HTML/CSS/JS	html/test.html	open in a browser	none (static file)
PHP	php/test.php	php test.php	PHP ≥ 8.1
Python	python/test.py	python -m unittest -v	Python ≥ 3.10
Rust	rust/ (Cargo bin)	cargo run	Rust toolchain
Swift	swift/ (SPM package)	swift test	Swift toolchain (Xcode / swift.org)
TypeScript	typescript/test.ts	npx tsx test.ts	Node.js + tsx, or tsc to type-check
Zig	zig/test.zig	zig test test.zig	Zig ≥ 0.14 (current stable)

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C — c/test.c

Compile and run from the c directory:

cd c
cc -std=c17 -Wall -Wextra -pedantic -O2 test.c -o test
./test

You can use gcc instead of cc. For additional static diagnostics:

cc -std=c17 -Wall -Wextra -pedantic -fanalyzer test.c -o /tmp/c-language-test

C++ — cpp/test.cpp

Compile and run from the cpp directory. The test requires C++20 for concepts and ranges:

cd cpp
c++ -std=c++20 -Wall -Wextra -pedantic -O2 test.cpp -o test
./test

You can use clang++ or g++ instead of c++. For sanitizer checks:

c++ -std=c++20 -Wall -Wextra -pedantic -fsanitize=address,undefined -g test.cpp -o /tmp/cpp-language-test
/tmp/cpp-language-test

The /tmp output paths keep diagnostic binaries out of the language-test directories.

Ruby — ruby/test.rb

Run from the ruby directory:

cd ruby
ruby test.rb

The test requires Ruby 3.4+ for the built-in Data.define feature. It covers immutable data objects, enumerable collections, keyword arguments, blocks, rescue/ensure, JSON parsing, Set, symbol-to-proc syntax, and monotonic clock timing.

For syntax and style diagnostics, Ruby installations with RuboCop can run:

rubocop test.rb

Go — go/test.go

A single runnable file exercising structs, interfaces, JSON, defer, goroutines, channels, select, and an HTTP server.

cd go
go run test.go

Starts an HTTP server on :8080. Try it in another terminal:

curl http://localhost:8080/users                  # GET list
curl -X POST -d '{"name":"Zed","email":"[email protected]"}' http://localhost:8080/users

Editor checks:

• go build ./... / go vet ./... for diagnostics
• gofmt -l . to verify formatting integration

Note: there are no _test.go files here, so go test ./... reports "no test files". The file is meant to be run, not unit-tested.

HTML / CSS / JS — html/test.html

A self-contained webpage with embedded <style> and <script> blocks. Open it directly in a browser:

open html/test.html        # macOS

Use the form: submit a name/role/notes to see entries appear in the dynamic list; use the Toggle Theme / Clear buttons. This exercises:

• HTML tag/attribute completion and Emmet expansion (div.card>h2{Title}+p{Content} is hinted at the bottom of the file)
• CSS custom properties, nesting in selectors, color previews
• JS DOM APIs, addEventListener, template literals

PHP — php/test.php

A script covering classes, readonly promoted properties, static analysis via ?:-free nullsafe/match expressions, fibers, enums, and interfaces.

cd php
php test.php

Output is the top-level fiber demo (suspends, resumes, prints). No output is printed for the User class / paginate() / statusLabel() — those exist to exercise highlighting, diagnostics, and go-to-definition.

Editor checks: install a PHP language server (e.g. Intelephense) to verify diagnostics on the deliberate restrict_types/db() calls.

Python — python/test.py

Requires Python 3.10+ (match/case, | union syntax, walrus).

Run the unittest suite:

cd python
python -m unittest -v test    # discovery by module name
# or
python test.py                # uses the built-in unittest.main() entry point

Note: module-level code in this file is only executed when run directly (python test.py); python -m unittest imports it without running main().

The file covers type hints, decorators (incl. @retry), dataclasses, generics (Stack[T]), generators, context managers, async/await, __slots__, properties, and 15 unittest cases.

Rust — rust/ (Cargo project)

A small Cargo project (rust/src/main.rs, binary test) covering traits, enums, generics, Arc<Mutex<>>, iterators, closures, and error handling.

cd rust
cargo run          # build + run the demo program
cargo build        # just compile
cargo test         # run any #[test]s added
cargo fmt --check  # formatting check

cargo run prints users, admins, and expected errors. target/ is build output; Cargo.lock is checked in intentionally.

Swift — swift/ (Swift Package)

A Swift package (swift/Package.swift) whose library target (Sources/LanguageTests/TestSuite.swift) exercises structs/classes, enums with associated values, generics (Stack<T>), protocols, closures, error handling (throws, Result, do/catch), inheritance, lazy computation, and Swift concurrency (actor, async/await, TaskGroup, Sendable). The XCTest suite lives at Tests/LanguageTestsTests/.

cd swift
swift build       # compile + fetch diagnostics
swift test        # run the XCTest suite
swift test --list-tests   # verify test discovery

Formatting check (requires swift-format, part of the Swift toolchain):

swift-format lint --strict Sources Tests

Build artifacts go to swift/.build/ (git-ignored).

TypeScript — typescript/test.ts

A self-contained module (no imports) covering generics, mapped/conditional types, template literal types, discriminated unions, typed event emitter, async/yield* generators.

Type-check without running:

cd typescript
npx tsc --noEmit --target es2022 --module esnext --strict test.ts

Run it with tsx (or bun, or Node ≥ 23 with type-stripping):

npx tsx test.ts
bun test.ts
node test.ts      # Node 23.6+ strips types at runtime

Zig — zig/test.zig

A single file with compile-time evaluation, error unions, tagged unions, slices/sentinels, packages via @import, and an embedded test block.

cd zig
zig test test.zig        # runs all `test "..."` blocks
zig fmt --check test.zig # formatting check

Expected output: a compact [n/...] test-runner summary. Note that the async/suspend section was deliberately removed because Zig ≥ 0.11 removed those features from the language; keep it that way to avoid syntax errors that would abort the whole file's test run.

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Image Tests

How to test editor features

Across any language file, try:

Feature	What to do
Highlighting	Open the file; scan for mis-colored comments/strings/keywords
Bracket matching	Click on {, (, [ and jump between matching pairs
Code folding	Fold function/class/struct/test bodies and comment blocks
Indentation	New line inside a block; paste a block and re-indent
Completion	Type a known identifier / call a method (e.g. repo., self.)
Diagnostics	Introduce a typo; the language server should flag it
Go-to-definition	Cmd/Alt-click an identifier to jump to its definition
Find references	Right-click a function name → Find All References
Rename	Rename a symbol; cross-references should update
Formatting	Run the language's formatter (gofmt/rustfmt/zig fmt/…)