accepts compiler.command on plugin options

src/compiler.test.ts

@@ -1,16 +1,14 @@
-import { beforeEach, expect, it, vi } from 'vitest'
+import { expect, it, vi } from 'vitest'
 //@ts-expect-error typing isn't provided
 import nodeElmCompiler from 'node-elm-compiler'
 
 import { compile } from './compiler.js'
 
-const compiled = `_Platform_export({'Hello':{'init':$author$project$Hello$main($elm$json$Json$Decode$string)({"versions":{"elm":"0.19.1"},"types":{"message":"Hello.Msg","aliases":{},"unions":{"Hello.Msg":{"args":[],"tags":{"Name":["String.String"]}},"String.String":{"args":[],"tags":{"String":[]}}}}})}});}(this));`
+const compiled = `_Platform_export({'Hello':{'init':$author$project$Hello$main($elm$json$Json$Decode$string)({'versions':{'elm':'0.19.1'},'types':{'message':'Hello.Msg','aliases':{},'unions':{'Hello.Msg':{'args':[],'tags':{'Name':['String.String']}},'String.String':{'args':[],'tags':{'String':[]}}}}})}});}(this));`
 
-beforeEach(() => {
+it('calls node-elm-compiler', async () => {
   vi.spyOn(nodeElmCompiler, 'compileToString').mockImplementation(() => compiled)
-})
 
-it('calls node-elm-compiler', async () => {
   expect(await compile(['a', 'b', 'c'], { debug: false, optimize: true, verbose: true })).toMatch(
     /export const Elm = {'Hello':/,
   )
@@ -22,3 +20,19 @@ it('calls node-elm-compiler', async () => {
     verbose: true,
   })
 })
+
+it('executes manual command', async () => {
+  expect(
+    await compile(['a', 'b', 'c'], {
+      command: () => `echo "${compiled.replace('$', '\\$')}"`,
+    }),
+  ).toMatch(/export const Elm = {'Hello':/)
+})
+
+it('executes manual command which fails', async () => {
+  expect(
+    compile(['a', 'b', 'c'], {
+      command: () => `whatever`,
+    }),
+  ).rejects.toBe('Failed to run command')
+})

src/compiler.ts

@@ -4,6 +4,8 @@ import { toESModule } from 'elm-esm'
 import nodeElmCompiler from 'node-elm-compiler'
 import { findUpSync } from 'find-up'
 import { dirname } from 'path'
+import { exec } from 'node:child_process'
+import { promisify } from 'node:util'
 
 import { injectAssets } from './assetsInjector.js'
 
@@ -18,17 +20,36 @@ export interface NodeElmCompilerOptions {
   verbose: boolean
 }
 
+export interface ManualCommand {
+  command: (targets: string[]) => string
+}
+
 const findClosestElmJson = (pathname: string) => {
   const elmJson = findUpSync('elm.json', { cwd: dirname(pathname) })
   return elmJson ? dirname(elmJson) : undefined
 }
 
-export const compile = async (targets: string[], options: Partial<NodeElmCompilerOptions>): Promise<string> => {
-  const compiled = await nodeElmCompiler.compileToString(targets, {
-    output: '.js',
-    cwd: findClosestElmJson(targets[0]),
-    ...options,
-  })
+export const compile = async (
+  targets: string[],
+  options: Partial<NodeElmCompilerOptions> | ManualCommand,
+): Promise<string> => {
+  const compiled =
+    'command' in options
+      ? await runCommandAndCapture(options.command(targets))
+      : await nodeElmCompiler.compileToString(targets, {
+          output: '.js',
+          cwd: findClosestElmJson(targets[0]),
+          ...options,
+        })
 
   return injectAssets(toESModule(compiled))
 }
+
+const runCommandAndCapture = async (command: string): Promise<string> => {
+  try {
+    const { stdout } = await promisify(exec)(command)
+    return stdout
+  } catch (e) {
+    throw 'Failed to run command'
+  }
+}

src/index.ts

@@ -82,7 +82,7 @@ export const plugin = (userOptions: Parameters<typeof parseOptions>[0] = {}): Pl
 
       const releaseLock = await acquireLock()
       try {
-        const compiled = await compile(targets, options.nodeElmCompilerOptions)
+        const compiled = await compile(targets, options.compilerOptions)
 
         // Apparently `addWatchFile` may not exist: https://github.com/hmsk/vite-plugin-elm/pull/36
         if (this.addWatchFile) {

src/pluginOptions.test.ts

@@ -7,7 +7,7 @@ describe('in dev build', () => {
   it('returns default in dev', () => {
     expect(parseOptions({})).toEqual<Result>({
       isBuild: false,
-      nodeElmCompilerOptions: {
+      compilerOptions: {
         debug: true,
         optimize: false,
         verbose: false,
@@ -18,7 +18,7 @@ describe('in dev build', () => {
   it('overwrites debug and optimize as it given', () => {
     expect(parseOptions({ debug: false, optimize: true })).toEqual<Result>({
       isBuild: false,
-      nodeElmCompilerOptions: {
+      compilerOptions: {
         debug: false,
         optimize: true,
         verbose: false,
@@ -33,14 +33,28 @@ describe('in dev build', () => {
       }),
     ).toEqual<Result>({
       isBuild: false,
-      nodeElmCompilerOptions: {
+      compilerOptions: {
         debug: true,
         optimize: false,
         verbose: false,
         pathToElm: 'wherever',
       },
     })
   })
+
+  it('accepts manual command which omits options for node-elm-compiler', () => {
+    expect(
+      parseOptions({
+        nodeElmCompilerOptions: { pathToElm: 'wherever' },
+        compiler: { command: () => 'special command' },
+      }),
+    ).toEqual<Result>({
+      isBuild: false,
+      compilerOptions: {
+        command: expect.any(Function),
+      },
+    })
+  })
 })
 
 describe('in production build', () => {
@@ -51,7 +65,7 @@ describe('in production build', () => {
   it('returns default for prod build', () => {
     expect(parseOptions({})).toEqual<Result>({
       isBuild: true,
-      nodeElmCompilerOptions: {
+      compilerOptions: {
         debug: false,
         optimize: true,
         verbose: true,
@@ -62,7 +76,7 @@ describe('in production build', () => {
   it('overwrites debug and optimize per just only debug', () => {
     expect(parseOptions({ debug: true })).toEqual<Result>({
       isBuild: true,
-      nodeElmCompilerOptions: {
+      compilerOptions: {
         debug: true,
         optimize: false,
         verbose: true,
@@ -73,7 +87,7 @@ describe('in production build', () => {
   it('overwrites debug and optimize', () => {
     expect(parseOptions({ debug: true, optimize: false })).toEqual<Result>({
       isBuild: true,
-      nodeElmCompilerOptions: {
+      compilerOptions: {
         debug: true,
         optimize: false,
         verbose: true,

src/pluginOptions.ts

@@ -1,25 +1,29 @@
-import { NodeElmCompilerOptions } from './compiler.js'
+import { ManualCommand, NodeElmCompilerOptions } from './compiler.js'
 
 interface InputOptions {
   debug?: boolean
   optimize?: boolean
   nodeElmCompilerOptions?: Partial<NodeElmCompilerOptions>
+  compiler?: {
+    command: (targets: string[]) => string
+  }
 }
 
 type DeterminedKeys = 'debug' | 'optimize' | 'verbose'
 
 interface ParsedOptions {
   isBuild: boolean
-  nodeElmCompilerOptions: Pick<NodeElmCompilerOptions, DeterminedKeys> &
-    Partial<Omit<NodeElmCompilerOptions, DeterminedKeys>>
+  compilerOptions:
+    | (Pick<NodeElmCompilerOptions, DeterminedKeys> & Partial<Omit<NodeElmCompilerOptions, DeterminedKeys>>)
+    | ManualCommand
 }
 
 export const parseOptions = (inputOptions: InputOptions): ParsedOptions => {
   const isBuild = process.env.NODE_ENV === 'production'
 
   return {
     isBuild,
-    nodeElmCompilerOptions: {
+    compilerOptions: inputOptions.compiler ?? {
       debug: inputOptions.debug ?? !isBuild,
       optimize: typeof inputOptions.optimize === 'boolean' ? inputOptions.optimize : !inputOptions.debug && isBuild,
       verbose: isBuild,