(fix/optim): only emit type declarations once

- every other emission is just a duplicate -- no need to spend compute
  to duplicate

- this also fixes a bug with multi-entry where if an entry in a subdir
  of src/ were added, e.g. src/foo/bar, the entire tree of type
  declarations would get output into dist/foo/src/*.d.ts
  - alternatively, could call `moveTypes()` with an arg for each entry,
    but there's no need since all declarations get produced the first
    time around anyway

Author: agilgur5

src/createRollupConfig.ts

@@ -20,7 +20,7 @@ const errorCodeOpts = {
 // shebang cache map thing because the transform only gets run once
 let shebang: any = {};
 
-export async function createRollupConfig(opts: TsdxOptions) {
+export async function createRollupConfig(opts: TsdxOptions, outputNum: number) {
   const findAndRecordErrorCodes = await extractErrors({
     ...errorCodeOpts,
     ...opts,
@@ -140,6 +140,8 @@ export async function createRollupConfig(opts: TsdxOptions) {
         tsconfigOverride: {
           compilerOptions: {
             target: 'esnext',
+            // only output declarations once
+            declaration: outputNum !== 0 ? false : undefined,
           },
         },
       }),

src/index.ts

@@ -164,9 +164,9 @@ async function createBuildConfigs(
             writeMeta: index === 0,
           }));
       })
-    ).map(async (options: TsdxOptions) => {
+    ).map(async (options: TsdxOptions, index: number) => {
       // pass the full rollup config to tsdx.config.js override
-      const config = await createRollupConfig(options);
+      const config = await createRollupConfig(options, index);
       return tsdxConfig.rollup(config, options);
     })
   );
@@ -475,10 +475,14 @@ prog
       const promise = asyncro
         .map(
           buildConfigs,
-          async (inputOptions: RollupOptions & { output: OutputOptions }) => {
+          async (
+            inputOptions: RollupOptions & { output: OutputOptions },
+            index: number
+          ) => {
             let bundle = await rollup(inputOptions);
             await bundle.write(inputOptions.output);
-            await moveTypes();
+            // declarations are only output on first run
+            if (index === 0) await moveTypes();
           }
         )
         .catch((e: any) => {