fixes #201 - export Typescript function header

src/lang/ts/mod.rs

@@ -14,6 +14,7 @@ pub use export_config::*;
 use reserved_terms::*;
 
 use crate::{
+ functions::FunctionDataType,
  internal::{skip_fields, skip_fields_named, NonSkipField},
  *,
 };
@@ -91,6 +92,53 @@ pub fn export_named_datatype(
  )
 }
 
+/// Convert a [FunctionDataType] into a function header like would be used in a `.d.ts` file.
+/// If your function requires a function body you can copy this function into your own codebase.
+///
+/// Eg. `function name();`
+pub fn export_function_header(dt: FunctionDataType, config: &ExportConfig) -> Result<String> {
+ let type_map = TypeMap::default();
+
+ let mut s = config
+ .comment_exporter
+ .map(|v| {
+ v(CommentFormatterArgs {
+ docs: &dt.docs,
+ deprecated: dt.deprecated.as_ref(),
+ })
+ })
+ .unwrap_or_default();
+
+ s.push_str("export ");
+
+ if dt.asyncness {
+ s.push_str("async ");
+ }
+
+ s.push_str("function ");
+
+ s.push_str(&dt.name);
+ s.push_str("(");
+ for (i, (name, ty)) in dt.args.into_iter().enumerate() {
+ if i != 0 {
+ s.push_str(", ");
+ }
+
+ s.push_str(&name);
+ s.push_str(": ");
+ s.push_str(&datatype(config, &ty, &type_map)?);
+ }
+ s.push_str(")");
+
+ if let Some(ty) = dt.result {
+ s.push_str(": ");
+ s.push_str(&datatype(config, &ty, &type_map)?);
+ }
+
+ s.push_str(";");
+ Ok(s)
+}
+
 #[allow(clippy::ptr_arg)]
 fn inner_comments(
  ctx: ExportContext,

tests/lib.rs

@@ -26,6 +26,7 @@ pub mod ts;
 mod ts_rs;
 mod ty_override;
 mod type_map;
+mod typescript;
 #[cfg(all(feature = "ulid", feature = "typescript"))]
 mod ulid;
 

tests/typescript/export_function_header.rs

@@ -0,0 +1,46 @@
+#![allow(deprecated)]
+
+use specta::{fn_datatype, functions::FunctionDataType, specta, ts::export_function_header};
+
+#[specta]
+fn a() {}
+#[specta]
+fn b() -> () {}
+#[specta]
+async fn c() {}
+#[specta]
+fn d() -> String {
+ "todo".into()
+}
+#[specta]
+fn e(a: String) {}
+#[specta]
+fn f(a: String, b: i32) {}
+#[specta]
+#[deprecated]
+fn g() {}
+
+#[test]
+fn test_export_function_header() {
+ assert(fn_datatype!(a), Ok("export function a();"));
+ assert(fn_datatype!(b), Ok("export function b(): null;"));
+ assert(fn_datatype!(c), Ok("export async function c();"));
+ assert(fn_datatype!(d), Ok("export function d(): string;"));
+ assert(fn_datatype!(e), Ok("export function e(a: string);"));
+ assert(
+ fn_datatype!(f),
+ Ok("export function f(a: string, b: number);"),
+ );
+ assert(
+ fn_datatype!(g),
+ Ok("/**\n * @deprecated\n */\nexport function g();"),
+ );
+}
+
+#[track_caller]
+fn assert(dt: FunctionDataType, result: specta::ts::Result<&str>) {
+ match export_function_header(dt, &Default::default()) {
+ Ok(s) => assert_eq!(result, Ok(s.as_str())),
+ Err(e) => assert_eq!(result, Err(e)),
+ }
+}

tests/typescript/mod.rs

@@ -0,0 +1 @@
+mod export_function_header;