README
¶
Formatter Package
This package formats generated source code before it is written to disk. Each language target dispatches to a language-specific formatter. Languages without a formatter pass through unchanged.
Dispatch
Format(target, fileName, data) in format.go routes by target and file extension:
| Target | Extensions | Formatter | Runtime |
|---|---|---|---|
csharp, unity |
.cs |
clang-format | wazero (WASM/WASI) |
typescript, mcp-typescript |
.ts, .js |
dprint-plugin-typescript | wazero (WASM) |
python |
.py |
dprint-plugin-ruff | wazero (WASM) |
java, javav2 |
.java |
dprint-plugin-java | wazero (WASM) |
ruby |
.rb, .rbi |
rubyfmt | wazero (WASM/WASI) |
php |
.php |
dprint-plugin-mago (mago) | wazero (WASM) |
go, cli, mockserver |
.go |
go/format (stdlib) |
native |
terraform |
.tf, .tfvars, .tftest.hcl |
hclwrite | native |
All other targets/extensions return data unchanged.
Embedded Binaries
The formatters that run via WASM have their binaries embedded into the Go binary at compile time using //go:embed:
| File | Source | How to rebuild |
|---|---|---|
clangfmt.wasm |
Built from LLVM source | cd formatters/clangfmt && ./build.sh |
dprint-plugin-typescript.wasm |
Pre-built from dprint releases | Download from dprint plugin registry |
dprint-plugin-ruff.wasm |
Pre-built from dprint releases | Download from dprint plugin registry |
dprint-plugin-java.wasm |
Pre-built from dprint releases | Download from dprint plugin registry |
dprint-plugin-mago.wasm |
Pre-built from dprint releases | Download from dprint plugin registry |
rubyfmt.wasm |
Built from Rust source | cd formatters/rubyfmt && ./build.sh |
Formatter Runtimes
wazero (WASM)
wazero is a zero-dependency WebAssembly runtime for Go.
dprint (dprint.go): The TypeScript, Python, Java, and PHP formatters use the dprint plugin ABI. A single WASM module is instantiated per language at startup and reused for all formatting calls. Communication happens through shared memory buffers and exported functions (format, set_file_path, get_formatted_text, etc.).
rubyfmt (rubyfmt.go): The Ruby formatter uses the simpler WASI stdin/stdout model. The WASM module is compiled once at startup, then a fresh instance is created per format call (each needs a unique module name). The Rust WASI binary imports env.__wasi_init_tp which is stubbed as a no-op. WASI proc_exit(0) is treated as success.
Native
Go files use the standard library go/format.Source(). Terraform files use the hclwrite package from HashiCorp (inlined MPL-2.0 code from the Terraform CLI).
WASM Build Tag
Files that depend on wazero are gated with //go:build !js || !wasm. When compiling to WASM itself (e.g. for browser use), dprint_wasm.go provides stub implementations that return data unchanged.
Build Projects
Formatter build tooling lives in the formatters/ directory at the repo root:
formatters/rubyfmt/— Rust/Cargo project for compiling rubyfmt to WASI WASM
Documentation
¶
Index ¶
Constants ¶
const NoFormatMarker = "__SPEAKEASY_NO_FORMAT__"
NoFormatMarker is the sentinel emitted by the `skipFormat` template function to signal that the rendered file must skip the formatting pipeline. It must appear as the very first bytes of the rendered file. The marker (and its trailing newline, if present) is stripped before the file is written to disk.
Variables ¶
This section is empty.
Functions ¶
func Prewarm ¶ added in v2.948.10
func Prewarm()
Prewarm starts compiling the WASM formatters (dprint, clang-format and rubyfmt) in the background so they are ready by the time generation formats its first file. Formatting calls the ensure functions itself, so Prewarm is only a latency optimisation. It is deliberately not run from init: commands that never format, such as lint and validate, should not pay for compiling the formatters.
func SetFormattingEnabled ¶
SetFormattingEnabled enables or disables formatting for a specific target. Used to gate formatting behind a gen.yaml config flag.
func ShouldSkipFormat ¶
Types ¶
This section is empty.
Source Files