fixed watch

src/build.ts

@@ -1,5 +1,5 @@
-import { build, BuildFailure } from 'esbuild'
-import { existsSync, readFileSync, writeFileSync, unlinkSync } from 'fs'
+import { build, BuildFailure, BuildOptions } from 'esbuild'
+import { existsSync, writeFileSync, unlinkSync } from 'fs'
 import { DistPath, ScriptPath } from './paths'
 import { UserScriptMetaFull } from './types'
 import readMeta from './readmeta'
@@ -12,16 +12,13 @@ export default async function (
 ): Promise<[UserScriptMetaFull, string | null]> {
     //read meta file
     let [metaJson, metaString] = readMeta(name)
-    let outPath = DistPath(name)
+    let path = ScriptPath(name)
+    let pathDist = DistPath(name)
 
-    let error: string | null = null
-
-    console.log('build watch?', !watchCallback ? false : 'obj')
-
-    try {
-        await build({
+    let result = await runEsbuild(
+        {
             entryPoints: [ScriptPath(name).main],
-            outfile: outPath,
+            outfile: pathDist,
 
             target: 'esnext',
             platform: 'node',
@@ -30,22 +27,6 @@ export default async function (
             bundle: true,
             minify: false,
 
-            // write: false, //TODO this will cause result.outputFiles to have the file contents so i can write the file instead
-
-            // watch: !watchCallback
-            //     ? false
-            //     : {
-            //           onRebuild(err, _result) {
-            //               console.log('onrebuild')
-            //               let error = null
-            //               if (err) {
-            //                   console.error(name, err)
-            //                   error = (err as BuildFailure).message
-            //               }
-            //               watchCallback(metaJson, error)
-            //           },
-            //       },
-
             define: {
                 UserScriptName: `'${metaJson.name}'`,
                 UserScriptNamespace: `'${metaJson.namespace}'`,
@@ -55,21 +36,125 @@ export default async function (
                 UserScriptSupportURL: `'${metaJson.supportURL}'`,
                 UserScriptHomepageURL: `'${metaJson.homepageURL}'`,
             },
-        })
-    } catch (err) {
-        console.error(name, err)
-        error = (err as BuildFailure).message
+        },
+        result => {
+            let error: string | null = null
+
+            if (result.error) {
+                console.error(name, result.errorRaw || result.error)
+                error = result.error
+            } else if (result.content) {
+                writeFileSync(pathDist, metaString + result.content)
+            } else {
+                console.error(name, 'No output')
+            }
+
+            doErrorFile(path.error, pathDist, error)
+
+            if (watchCallback !== false) {
+                watchCallback(metaJson, error)
+            }
+        },
+        watchCallback !== false
+    )
+
+    let error: string | null = null
+
+    if (result.error) {
+        console.error(name, result.errorRaw || result.error)
+        error = result.error
+    } else if (result.content) {
+        writeFileSync(pathDist, metaString + result.content)
+    } else {
+        console.error(name, 'No output')
     }
 
-    //add UserScript header
-    if (existsSync(outPath)) {
-        if (!error) {
-            let content = readFileSync(outPath).toString()
-            writeFileSync(outPath, metaString + content)
-        } else {
-            unlinkSync(outPath)
-        }
-    }
+    doErrorFile(path.error, pathDist, error)
 
     return [metaJson, error]
 }
+
+function doErrorFile(
+    pathError: string,
+    pathOutFile: string,
+    error: string | null
+) {
+    if (error !== null) {
+        writeFileSync(pathError, `${new Date().toISOString()}\n\n${error}`)
+
+        if (existsSync(pathOutFile)) {
+            unlinkSync(pathOutFile)
+        }
+    } else if (existsSync(pathError)) {
+        unlinkSync(pathError)
+    }
+}
+
+interface RunEsbuildResult {
+    content: string | null
+    error: string | null
+    errorRaw?: BuildFailure
+}
+
+async function runEsbuild(
+    opts: BuildOptions,
+    watchCallback: (result: RunEsbuildResult) => void,
+    toWatch: boolean = false
+): Promise<RunEsbuildResult> {
+    opts.write = false
+    if (toWatch) {
+        opts.watch = {
+            onRebuild(err, res) {
+                if (err) {
+                    watchCallback({
+                        content: null,
+                        error: (err as BuildFailure).message,
+                        errorRaw: err,
+                    })
+                } else if (res) {
+                    let content = ''
+                    if (res.outputFiles && res.outputFiles.length > 0) {
+                        content = res.outputFiles[0].text
+                    }
+                    if (content === '') {
+                        watchCallback({
+                            content: null,
+                            error: 'No output',
+                        })
+                    }
+                    watchCallback({
+                        content,
+                        error: null,
+                    })
+                } else {
+                    watchCallback({
+                        content: null,
+                        error: 'No result',
+                    })
+                }
+            },
+        }
+    }
+    try {
+        let res = await build(opts)
+        let content = ''
+        if (res.outputFiles && res.outputFiles.length > 0) {
+            content = res.outputFiles[0].text
+        }
+        if (content === '') {
+            return {
+                content: null,
+                error: 'No output',
+            }
+        }
+        return {
+            content,
+            error: null,
+        }
+    } catch (err) {
+        return {
+            content: null,
+            error: (err as BuildFailure).message,
+        }
+    }
+}