Native /edit: a small, safe editor for one text file (#402)

CHANGELOG.md

@@ -10,6 +10,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
 - **`/view`, a native read-only viewer** for files and completed output ([#397](https://github.com/raiseCatError/notMyShell/issues/397)). `/view README.md` opens a file relative to the shell's directory (`~` for home): Markdown renders (`m` shows the source), source files get syntax colors and line numbers, `.diff`/`.patch` files and `git diff`/`git show` output read as diffs. `/view N` opens completed output N (numbered as `/copy` numbers it) and `/view` the latest; Actions → View output does the same for a block. Find with `/` and `n`/`N`, go to a line with `:`, `w` toggles wrapping (Left/Right scroll sideways), `l` line numbers, `c` copies the whole text, Esc closes. Viewing never changes the file or the transcript.
   - Limits: regular files only (directories, devices and pipes are refused), at most 8 MiB and 200,000 lines (the rest is named, with `less` or an editor as the way to read it), binary and UTF-16 files are refused, invalid UTF-8 is shown with `�` and a note. Control characters, escape sequences and invisible format characters are shown as visible marks, never interpreted. Open in pager, `less`, `bat` and Glow are unchanged.
+- **`/edit`, a small native editor** for one text file ([#402](https://github.com/raiseCatError/notMyShell/issues/402)). `/edit notes.md` (or `e` in `/view`) opens the file in a panel: type, select with Shift, Ctrl+Z / Ctrl+Y undo and redo, Ctrl+F find, Ctrl+C / Ctrl+X copy and cut, Ctrl+S save, Esc close (it asks about unsaved changes). A path that does not exist yet is created on the first save. It is for quick edits, not an IDE: `vim`, `nano`, `micro` and your `$EDITOR` still run as usual.
+  - Safe saving: the new text is written beside the file and renamed over it, keeping its mode, group, line endings, BOM and final newline; a symlink stays a symlink. If the file changed, was replaced or was deleted since you opened it, nothing is written until you choose Keep editing, Overwrite or Reload. A new file never replaces one that appeared meanwhile.
+  - Limits: your own regular UTF-8 text files up to 1 MiB with one hard link, writable, with one kind of line ending. Others are refused with the reason and stay readable in `/view`. Extended attributes and ACLs are not carried over by a save. Unsaved text is lost if the NMSh window itself is closed.
 
 ### Fixed
 

docs/development/v021-ledger.md

@@ -17,7 +17,7 @@ Automated results here are not physical-terminal validation.
 | 0 | Design and ledger | #410 | `docs/v021-design` / #411 | | PR open, CI green; awaiting merge |
 | 1 | Reliability gates | #403, #408, #388 | `fix/v021-reliability` (stacked on #411) | | PR open |
 | 2 | `/view` | #397, #402 | `feature/v021-view` (stacked on slice 1) | | PR open |
-| 3 | `/edit` | #402 | | | |
+| 3 | `/edit` | #402 | `feature/v021-edit` (stacked on slice 2) | | PR open |
 | 4 | Semantic Output | #386 | | | |
 | 5 | `/track` | #393 (#394) | | | |
 | 6 | Modules and diagnostics | #364, #365 | | | |
@@ -35,7 +35,7 @@ Automated results here are not physical-terminal validation.
 
 Checklist: [v0.21 physical QA](../testing/v021-physical-qa.md). Slice 1: section 1 (multi-row progress in Ghostty
 and Terminal.app, queued highlight colors). Slice 2: section 2 (`/view` keys, rendering, refusals, hostile text,
-NO_COLOR).
+NO_COLOR). Slice 3: section 3 (`/edit` editing keys, saving, conflicts, refusals).
 
 ## Verification notes
 

docs/testing/v021-physical-qa.md

@@ -18,6 +18,8 @@
 | 1 Multi-row progress (#388) | Terminal.app | macOS | Bash or Fish | | Not run | |
 | 2 `/view` | Ghostty | macOS | zsh | | Not run | |
 | 2 `/view` | Terminal.app | macOS | zsh | | Not run | |
+| 3 `/edit` | Ghostty | macOS | zsh | | Not run | |
+| 3 `/edit` | Terminal.app | macOS | Bash or Fish | | Not run | |
 
 ## 1. Multi-row progress redraws (#388)
 
@@ -50,3 +52,20 @@
 - [ ] 2.8 Esc closes, the composer draft and cursor are where they were, and a running command's output kept
   arriving underneath. At 32×10 the viewer still fits and Esc is shown.
 - [ ] 2.9 `NO_COLOR=1` and Safe glyphs: matches and the current match are still visible (reverse video).
+
+## 3. Native editor (`/edit`)
+
+- [ ] 3.1 `/edit notes.txt` in an empty folder: it says *new file*; type two lines with Enter and a Tab, Ctrl+S says
+  *Saved*, Esc returns to the composer, `cat -A notes.txt` shows the tab and a final newline.
+- [ ] 3.2 Shift+arrows, Shift+Alt+arrows and Cmd+Shift+arrows select; typing replaces the selection; Ctrl+C copies
+  and Ctrl+X cuts it (paste it back with the terminal's paste); Ctrl+Z undoes a typed word in one step, Ctrl+Y redoes.
+- [ ] 3.3 Ctrl+F finds (lowercase ignores case), Enter again finds the next match.
+- [ ] 3.4 Edit, then Esc: the question offers Save, Discard changes and Keep editing; each does what it says.
+- [ ] 3.5 Conflict: `/edit notes.txt`, change it from another terminal (`echo x >> notes.txt`), then Ctrl+S: nothing is
+  written until you choose; Overwrite writes yours, Reload shows theirs.
+- [ ] 3.6 A CRLF file with a BOM keeps both after saving (`xxd file | head -1`); `chmod 640` survives a save; editing
+  through a symlink keeps the symlink.
+- [ ] 3.7 Refusals: a binary (`/edit /bin/ls`), a root-owned file (`/edit /etc/hosts`), a 2 MB file, a read-only file
+  (`chmod 444`) each explain why, and `/view` still opens them.
+- [ ] 3.8 `e` in `/view README.md` opens the editor on the same file; `vim notes.txt` and `nano notes.txt` still run as
+  usual from the composer.

src/app/TerminalApp.ts

@@ -70,6 +70,8 @@ import {configuredEditor} from '../host/HostActions.js';
 import {comparePanelKey, createComparePanel, renderComparePanel, type ComparePanelState} from '../ui/ComparePanel.js';
 import {loadFileDocument, outputDocument} from '../viewer/document.js';
 import {createViewer, renderViewer, viewerKey, type ViewerLook, type ViewerState} from '../viewer/ViewerPanel.js';
+import {createEditor, editorKey, renderEditor, type EditorAction, type EditorState} from '../viewer/EditorPanel.js';
+import {openForEdit, saveFile} from '../viewer/fileEdit.js';
 import {buildComparisonReport, copyableDiff, previousRun} from '../output/compare.js';
 import {createStripStudio, renderStripStudio, stripStudioKey, type StripStudioState} from '../status/StripStudio.js';
 import {configureListKey, renderConfigureList, type ConfigureListState} from '../tools/config/ConfigureList.js';
@@ -1622,11 +1624,20 @@ export class TerminalApp {
       this.render();
       return;
     }
+    if (this.textEditor) {
+      const editor = this.textEditor;
+      const {columns, rows} = this.dimensions();
+      const action = editorKey(editor, key, columns, rows - 4);
+      if (action) this.runEditorAction(editor, action);
+      this.render();
+      return;
+    }
     if (this.viewer) {
       const viewer = this.viewer;
       const {columns, rows} = this.dimensions();
       const action = viewerKey(viewer, key, columns, rows - 4, this.viewerLook());
       if (action?.kind === 'close') { this.viewer = undefined; this.returnFromPanel(); }
+      else if (action?.kind === 'edit') { this.viewer = undefined; this.openTextEditor(action.path, '/edit', viewer); }
       else if (action?.kind === 'copy') {
         void this.copyText(action.text, 'Copied the document').then(note => { if (note && this.viewer === viewer) { viewer.note = note; this.render(); } });
       }
@@ -2887,6 +2898,10 @@ export class TerminalApp {
     }
     else if (slash.kind === 'pins') { this.panelOrigin = undefined; this.openPins(); }
     else if (slash.kind === 'view') this.openViewer(slash.target, command.trim());
+    else if (slash.kind === 'editFile') {
+      if (!slash.target) this.output.addFrontendInteraction(command.trim(), 'Name a file: /edit notes.md. Your own editor and vim, nano or micro still work as usual.', INFO);
+      else this.openTextEditor(slash.target, command.trim());
+    }
     else if (slash.kind === 'compare') {
       if (slash.error) this.output.addFrontendInteraction(command.trim(), slash.error, ERROR);
       else {
@@ -3603,6 +3618,61 @@ export class TerminalApp {
     });
   }
 
+  /**
+   * /edit: open one small text file in NMSh's editor, or say in the transcript why it cannot be edited (refused files
+   * stay readable in /view). `returnTo` is the viewer it was opened from; it is reopened if the file cannot be edited.
+   */
+  private openTextEditor(target: string, command: string, returnTo?: ViewerState): void {
+    void openForEdit(target, this.shellCwd).then(result => {
+      if (this.stopped) return;
+      if (!result.ok) {
+        if (returnTo && !this.hasModalInput()) { returnTo.note = result.reason; this.viewer = returnTo; }
+        else this.output.addFrontendInteraction(command, result.reason, ERROR);
+        this.render();
+        return;
+      }
+      if (this.hasModalInput()) return;
+      this.panelOrigin = undefined;
+      this.textEditor = createEditor(result.file);
+      this.render();
+    });
+  }
+
+  /** The editor's requests that touch the disk or the clipboard; the panel shows the outcome. */
+  private runEditorAction(editor: EditorState, action: EditorAction): void {
+    if (action.kind === 'close') { this.textEditor = undefined; this.returnFromPanel(); return; }
+    if (action.kind === 'copy') {
+      void this.copyText(action.text, 'Copied').then(note => { if (note && this.textEditor === editor) { editor.note = {text: note, tone: 'success'}; this.render(); } });
+      return;
+    }
+    editor.busy = true;
+    if (action.kind === 'reload') {
+      void openForEdit(editor.file.path, this.shellCwd).then(result => {
+        editor.busy = false;
+        if (this.textEditor !== editor) return;
+        if (!result.ok) { editor.note = {text: result.reason, tone: 'error'}; this.render(); return; }
+        this.textEditor = {...createEditor(result.file), note: {text: 'Reloaded from disk; your changes were discarded.', tone: 'info'}};
+        this.render();
+      });
+      return;
+    }
+    const lines = [...editor.buffer.lines];
+    void saveFile(editor.file, lines, {...(action.force ? {force: true} : {})}).then(result => {
+      editor.busy = false;
+      if (this.textEditor !== editor) return;
+      if (result.ok) {
+        editor.file = result.file;
+        // Only what was written is clean: typing during the save stays unsaved.
+        if (editor.buffer.lines.length === lines.length && editor.buffer.lines.every((line, index) => line === lines[index])) editor.buffer.markSaved();
+        if (action.thenClose) { this.textEditor = undefined; this.returnFromPanel(); }
+        else editor.note = {text: `Saved ${editor.file.title}.`, tone: 'success'};
+      } else if (result.conflict) {
+        editor.dialog = {kind: 'conflict', focus: 0, conflict: result.conflict, reason: result.reason, ...(action.thenClose ? {thenClose: true} : {})};
+      } else editor.note = {text: `${result.reason} Your text is still here.`, tone: 'error'};
+      this.render();
+    });
+  }
+
   /** View output: the record's stored output, numbered as /copy numbers it. */
   private openOutputViewer(record: CompletedCommand): void {
     const number = this.output.recentShellCommands().indexOf(record) + 1;
@@ -4964,7 +5034,7 @@ export class TerminalApp {
   private get settingsPanelActive(): boolean { return this.hasModalInput(); }
 
   private hasModalInput(ignorePalette = false): boolean {
-    return Boolean(this.stopsEditor || this.chromeEditor || this.screensaverPanel || this.themeStudio || this.themeBridgePanel || this.rowPanel || this.copyPicker || this.summaryReview || this.reportReview || this.comparePanel || this.viewer || this.background.panel || this.batchReview || this.pinsPanel || this.stripStudio || this.configureList || this.tmuxPanel || this.dotfiles || this.setupState || this.installPrompt || this.presetPanel || this.toolsPanel || this.toolConfigurationLoading || this.toolConfiguration || this.promptPanelState || this.transcriptPanelState || this.providerPanelState || (!ignorePalette && this.paletteState) || this.syntaxPanelState || this.layoutPanelState || this.settingsPanelState
+    return Boolean(this.stopsEditor || this.chromeEditor || this.screensaverPanel || this.themeStudio || this.themeBridgePanel || this.rowPanel || this.copyPicker || this.summaryReview || this.reportReview || this.comparePanel || this.viewer || this.textEditor || this.background.panel || this.batchReview || this.pinsPanel || this.stripStudio || this.configureList || this.tmuxPanel || this.dotfiles || this.setupState || this.installPrompt || this.presetPanel || this.toolsPanel || this.toolConfigurationLoading || this.toolConfiguration || this.promptPanelState || this.transcriptPanelState || this.providerPanelState || (!ignorePalette && this.paletteState) || this.syntaxPanelState || this.layoutPanelState || this.settingsPanelState
       || this.resumeBrowser || this.appearanceHub || this.keyboardState || this.startupPanel || this.aboutPanel || this.shellPanel || this.openPanel || this.askState || this.agentView || this.agentPanel || this.launcher || this.modsPanel || this.worktreePanel || this.githubPanel || this.providersOverview || this.understandingPanel || this.cursorPanel || this.doctorPanel || this.watchPanel || this.queuePanel || this.queueHistoryPanel || this.pasteReview || this.misePanel || this.keepAwakePanel);
   }
 
@@ -5007,6 +5077,7 @@ export class TerminalApp {
     if (this.reportReview) return renderReportReview(this.reportReview, columns, this.dimensions().rows - 4);
     if (this.comparePanel) return renderComparePanel(this.comparePanel, columns, this.dimensions().rows - 4);
     if (this.viewer) return renderViewer(this.viewer, columns, this.dimensions().rows - 4, this.viewerLook());
+    if (this.textEditor) return renderEditor(this.textEditor, columns, this.dimensions().rows - 4);
     if (this.background.panel) return framePanel(this.background.panelRows(Math.max(1, columns - 4), this.dimensions().rows - 4,
       {now: Date.now(), color: colorLevel() !== 'none', safe: getCurrentGlyphMode() === 'safe'}), columns);
     if (this.rowPanel) return renderRowPanel(this.rowPanel, this.promptConfiguration, columns, this.dimensions().rows, this.rowPanelPreview(columns));
@@ -5939,6 +6010,8 @@ export class TerminalApp {
   private viewer?: ViewerState;
   /** A file /view is still reading; a newer request or Esc cancels it. */
   private viewerLoad?: AbortController;
+  /** NMSh's small text editor (/edit, e in /view); owns keys while open. */
+  private textEditor?: EditorState;
   private clipboardNote?: {text: string; tone: 'success' | 'info' | 'error'; until: number};
   private clipboardNoteTimer?: ReturnType<typeof setTimeout>;
   /** The block whose Copy control just succeeded (by startId), shown as "Copied" until `until`. */

src/ask/concepts.ts

@@ -256,6 +256,9 @@ export const CONCEPTS: readonly Concept[] = [
   {id: 'view', label: 'View a file or output', support: 'actionable', open: '/view', covers: ['/view'],
     aliases: ['view file', 'view a file', 'read a file', 'open a file read only', 'view output', 'read markdown', 'preview markdown', 'view log', 'pager'],
     description: '/view opens a read-only native viewer: /view README.md for a file (Markdown renders; m shows the source), /view N for completed output N (numbered as /copy), /view alone for the latest output. Also Actions → View output. Find with /, n/N, go to a line with :, w wraps, l numbers, c copies the whole text. less, bat and Glow still work as usual.'},
+  {id: 'edit-file', label: 'Edit a small text file', support: 'actionable', open: '/edit', covers: ['/edit'],
+    aliases: ['edit a file', 'edit file', 'edit text file', 'change a config file', 'quick edit', 'small editor', 'native editor', 'edit notes'],
+    description: '/edit notes.md opens a small text file (up to 1 MiB, your own, UTF-8) in NMSh\'s editor: type, select with Shift, Ctrl+Z undo, Ctrl+Y redo, Ctrl+F find, Ctrl+C/Ctrl+X copy and cut, Ctrl+S saves (atomically; if the file changed on disk you choose Overwrite, Reload or Keep editing), Esc closes and asks about unsaved changes. e in /view edits the file shown. vim, nano, micro and your $EDITOR still work as usual.'},
   {id: 'paste-batch', label: 'Paste and queue a batch', support: 'actionable', open: '/ps', covers: ['/ps', '/clips'],
     aliases: ['paste commands', 'paste batch', 'paste from clipboard', 'queue pasted commands', 'review pasted commands', 'ps command', 'run as block'],
     description: '/ps reads the clipboard once and shows Paste Review. B reviews a safe batch with choices to run as one block, queue separately, edit or cancel; quotes, loops and heredocs stay whole. C deliberately keeps a clip in memory; /clips reviews it before insertion. Clips disappear when this frontend exits. Nothing executes automatically.'},
@@ -367,7 +370,7 @@ export const GUIDE_SECTIONS: readonly GuideSection[] = [
   {id: 'chroma', title: 'Chroma', why: 'Optional gradients and motion for NMSh-owned chrome only; your command output is never recolored.', concepts: ['chroma', 'effects', 'activity']},
   {id: 'shells', title: 'Shells', why: 'One NMSh window can run zsh, Fish or Bash, and you can leave for a plain shell and come back.', concepts: ['shell', 'leave', 'otherShells']},
   {id: 'completion', title: 'Completion & suggestions', why: 'Tab completion lists real candidates; ghost suggestions predict the rest of the line.', concepts: ['completion', 'suggestions']},
-  {id: 'history', title: 'History & transcripts', why: 'Find what you ran and what it printed, now or in earlier sessions.', concepts: ['history', 'picker', 'transcript', 'find', 'copy', 'output-actions', 'view', 'compare', 'transcripts', 'pins']},
+  {id: 'history', title: 'History & transcripts', why: 'Find what you ran and what it printed, now or in earlier sessions.', concepts: ['history', 'picker', 'transcript', 'find', 'copy', 'output-actions', 'view', 'edit-file', 'compare', 'transcripts', 'pins']},
   {id: 'sessions', title: 'Sessions', why: 'Sessions keep running when a window closes; reattach, switch or get notified.', concepts: ['sessions', 'queue', 'agentSessions', 'presets', 'notices', 'commandNotifications', 'panes', 'keepAwake']},
   {id: 'ask', title: 'Ask', why: 'Plain-English help that knows NMSh, your commands and this repository, and never runs anything you did not confirm.', concepts: ['ask']},
   {id: 'intelligence', title: 'Local intelligence', why: 'An optional local model helps Ask map vague requests to known actions. It runs on this machine, never writes commands, and Ask works fully without it.', concepts: ['understanding'],