Implement edit and exit

src/index.ts

@@ -23,7 +23,8 @@ const output: OutputManager = {
     clipboard: new WlClipboard,
 }
 
-const exec = new Executor(output, parser)
+const exec = new Executor(output, parser, input)
+exec.adoptLifecycle(lifecycle)
 exec.subscribe(state => state.outputSubject())
 
 input.setupPrompt()

src/util/fs.ts

@@ -0,0 +1,3 @@
+import crypto from "node:crypto";
+
+export const tempFile = () => `/tmp/str-${crypto.randomBytes(4).readUInt32LE(0)}.txt`

src/vm/commands/edit.ts

@@ -1,7 +1,10 @@
-import {Command, ParseContext} from "./command.js";
+import {Command, ParseContext, wrapString} from "./command.js";
 import {LexInput} from "../lexer.js";
 import {StrVM} from "../vm.js";
 import {Awaitable} from "../../util/types.js";
+import fs from "node:fs/promises";
+import childProcess from "node:child_process";
+import {tempFile} from "../../util/fs.js";
 
 export class Edit extends Command<{}> {
     isParseCandidate(token: LexInput): boolean {
@@ -19,8 +22,17 @@ export class Edit extends Command<{}> {
     execute(vm: StrVM, data: {}): Awaitable<StrVM> {
         return vm.replaceContextMatchingTerm({
             string: async sub => {
+                await vm.control$.next({ cmd: 'close-prompt' })
 
-                return sub
+                const tmp = tempFile()
+                await fs.writeFile(tmp, sub, 'utf8')
+                const proc = childProcess.spawn(process.env.EDITOR || 'vim', [tmp], { stdio: 'inherit' })
+                await new Promise<void>(res => {
+                    proc.on('close', () => res())
+                })
+
+                await vm.control$.next({ cmd: 'restore-prompt' })
+                return (await fs.readFile(tmp, 'utf8')).toString()
             }
         })
     }

src/vm/input.ts

@@ -1,11 +1,22 @@
 import * as readline from 'node:readline'
 import {BehaviorSubject} from "../util/subject.js";
 import {Lifecycle, LifecycleAware} from "../util/lifecycle.js";
+import {StreamLogger} from "../util/log.js";
+import {log} from "../log.js";
 
 export class Input extends BehaviorSubject<string> implements LifecycleAware {
 	private rl?: readline.Interface
+	private log: StreamLogger = log.getStreamLogger('input')
+
+	public hasPrompt(): boolean {
+		return !!this.rl
+	}
 
 	public setupPrompt(): void {
+		this.log.verbose({
+			setupPrompt: { hasExistingPrompt: !!this.rl },
+		})
+
 		if ( this.rl ) {
 			this.closePrompt()
 		}
@@ -25,6 +36,10 @@ export class Input extends BehaviorSubject<string> implements LifecycleAware {
 	}
 
 	public closePrompt(): void {
+		this.log.verbose({
+			closePrompt: { hasExistingPrompt: !!this.rl },
+		})
+
 		this.rl?.close()
 		this.rl = undefined
 	}

src/vm/output.ts

@@ -3,6 +3,7 @@ import {Awaitable} from "../util/types.js";
 import childProcess from "node:child_process";
 import fs from "node:fs";
 import crypto from "node:crypto";
+import {tempFile} from "../util/fs.js";
 
 export const getSubjectDisplay = (sub: StrRVal): string => {
     if ( sub.term === 'string' ) {
@@ -53,7 +54,6 @@ export class FakeClipboard {
     }
 }
 
-const tempFile = () => `/tmp/str-${crypto.randomBytes(4).readUInt32LE(0)}.txt`
 export class WlClipboard {
     async read(): Promise<string> {
         const tmp = tempFile()

src/vm/vm.ts

@@ -15,6 +15,8 @@ import {Parser} from "./parser.js";
 import {log} from "../log.js";
 import {Executable} from "./parse.js";
 import {getSubjectDisplay, OutputManager} from "./output.js";
+import {Input} from "./input.js";
+import {Lifecycle, LifecycleAware} from "../util/lifecycle.js";
 
 export class Scope {
     private entries: Record<string, StrRVal> = {}
@@ -250,29 +252,41 @@ export class ExecutionContext {
 }
 
 export type Control =
-    { cmd: 'undo' | 'redo' | 'exit' | 'no-show' | 'preserve-history' }
+    { cmd: 'undo' | 'redo' | 'exit' | 'no-show' | 'preserve-history' | 'close-prompt' | 'restore-prompt' }
 
-export class StrVM {
-    public static make(output: OutputManager): StrVM {
+export class StrVM implements LifecycleAware {
+    public static make(output: OutputManager, input?: Input): StrVM {
         return new StrVM(
             new ExecutionContext(wrapString(''), new Scope()),
             output,
+            input,
         )
     }
 
     private noShowNext: boolean = false
     private preserveHistoryNext: boolean = false
+    private wasPromptWhenClosed: boolean = false
     public readonly control$: BehaviorSubject<Control> = new BehaviorSubject()
+    private log: StreamLogger
+    private lifecycle?: Lifecycle
 
     constructor(
         private context: ExecutionContext,
         private output: OutputManager,
+        private input?: Input,  // if provided, commands will properly handle prompt control
     ) {
+        this.log = log.getStreamLogger('vm')
         this.control$.subscribe((control: Control) =>
             this.handleControl(control))
     }
 
+    adoptLifecycle(lifecycle: Lifecycle): void {
+        this.lifecycle = lifecycle
+    }
+
     private async handleControl(control: Control) {
+        this.log.debug({ handlingControl: control })
+
         if ( control.cmd === 'no-show' ) {
             this.noShowNext = true
         } else if ( control.cmd === 'preserve-history' ) {
@@ -281,6 +295,18 @@ export class StrVM {
             this.context.restoreHistory()
         } else if ( control.cmd === 'redo' ) {
             this.context.restoreForwardHistory()
+        } else if ( control.cmd === 'close-prompt' ) {
+            this.wasPromptWhenClosed = !!this.input?.hasPrompt()
+            if ( this.wasPromptWhenClosed ) {
+                this.input?.closePrompt()
+            }
+        } else if ( control.cmd === 'restore-prompt' ) {
+            if ( this.wasPromptWhenClosed && !this.input?.hasPrompt() ) {
+                this.input?.setupPrompt()
+            }
+            this.wasPromptWhenClosed = false
+        } else if ( control.cmd === 'exit' ) {
+            this.lifecycle?.close()
         }
     }
 
@@ -332,7 +358,11 @@ export class StrVM {
     }
 
     makeChild(): StrVM {
-        return new StrVM(this.context.makeChild(), this.output)
+        const child = new StrVM(this.context.makeChild(), this.output, this.input)
+        if ( this.lifecycle ) {
+            child.adoptLifecycle(this.lifecycle)
+        }
+        return child
     }
 
     async outputSubject(): Promise<void> {
@@ -345,17 +375,30 @@ export class StrVM {
     }
 }
 
-export class Executor extends BehaviorSubject<StrVM> {
+export class Executor extends BehaviorSubject<StrVM> implements LifecycleAware{
     private logger: StreamLogger
+    private lifecycle?: Lifecycle
 
-    constructor(private output: OutputManager, parser?: Parser) {
+    constructor(private output: OutputManager, parser?: Parser, private input?: Input) {
         super()
         this.logger = log.getStreamLogger('executor')
         parser?.subscribe(exec  => this.handleExecutable(exec))
     }
 
+    adoptLifecycle(lifecycle: Lifecycle): void {
+        this.lifecycle = lifecycle
+    }
+
     async handleExecutable(exec: Executable<CommandData>) {
-        const vm = this.currentValue || StrVM.make(this.output)
+        const vm = this.currentValue || this.makeVM()
         await this.next(await exec.command.execute(vm, exec.data))
     }
+
+    private makeVM(): StrVM {
+        const vm = StrVM.make(this.output, this.input)
+        if ( this.lifecycle ) {
+            vm.adoptLifecycle(this.lifecycle)
+        }
+        return vm
+    }
 }