Merge pull request #469 from irisitymichaelgrundberg/feat/copy-dedent-pane-margin

feat(terminal): take the transcript gutter off a copy, at the width the CLI declares

src/config/cli-registry/schema.ts

@@ -294,6 +294,23 @@ const capabilitiesSchema = z
     effort: z.boolean(),
     agentSkillInjection: z.boolean(),
     statusLineTelemetry: z.boolean(),
+    // How many columns this CLI indents its transcript body by, so a copy can take
+    // that much off the clipboard. Bounded, because it is the whole strip: a copy
+    // never removes more than this, nor more than every selected line shares.
+    //
+    // ⚠ DECLARED, not measured off the pane, and two measured attempts are why.
+    // Asking whether the pane painted spaces across the unused part of each row
+    // separates a TUI from a shell perfectly where it fires and never
+    // over-stripped, but it is a function of pane WIDTH: that padding exists
+    // only while a rendered line stops short of the CLI's own layout width, and
+    // Claude Code's prose wraps to fill it — the share of padded rows on one
+    // live transcript ran 44%, 6%, 6%, 7% and 87% at 123, 160, 198, 235 and 298
+    // columns, so the strip did nothing at any ordinary size. Taking the
+    // narrowest indent on screen instead fires everywhere and over-strips, since
+    // a file listing inside the transcript can be the narrowest thing on it.
+    // A declared width cannot do either. Absent means no strip, so a CLI whose
+    // transcript layout nobody has measured is never touched.
+    transcriptGutter: z.number().int().min(1).max(8).optional(),
     workDetect: z
       .object({
         promptGlyph: z.string().min(1).max(8),

src/config/cli-registry/stock.ts

@@ -210,6 +210,10 @@ const CLAUDE: CliEntry = {
   },
   capabilities: {
     external: false,
+    // Claude indents its transcript body two columns and puts its own ●/✻/❯ markers
+    // in them, so a copy can drop two and paste flush. The only entry that declares
+    // this, because it is the only one whose gutter has been measured.
+    transcriptGutter: 2,
     // The historical hard-coded pair, now stated as data. `workingLine` matches both the
     // `✻ Actualizing… (39s · ↓ 2.0k tokens)` status line and the bare `esc to interrupt`
     // footer, because tmux repaints partially and only one of the two may land in a chunk.
@@ -529,6 +533,12 @@ const CODEX: CliEntry = {
     // braille spinner, and it never prints `esc to interrupt` at rest, so that phrase
     // alone separates a running turn from an idle one.
     workDetect: { promptGlyph: '›', workingLine: '[Ee]sc to interrupt' },
+    // Two columns, like claude's, measured on a live 0.154.0 answer: the `•`/`›`/`⚠`
+    // markers sit in the gutter, prose continuations sit at 2, and a nested YAML block
+    // the model wrote rendered at 2/4/6/8 for its own 0/2/4/6. Replayed at 100, 120,
+    // 160, 198, 235 and 282 columns the indents were 0, 2, 4, 6 and 8 at every one,
+    // never 1, so the width is not a function of the pane.
+    transcriptGutter: 2,
     transcript: 'codex-rollout',
     altScreen: 'strip-full',
     echo: { policy: 'predict', anchor: { kind: 'cursor' }, predictProfile: 'codex' },

src/config/cli-registry/types.ts

@@ -345,6 +345,29 @@ export interface CliCapabilities {
     /** Source of a regex matching the status line this CLI draws while a turn runs. */
     workingLine: string;
   };
+  /**
+   * How many columns this CLI indents its transcript body by, so a copy taken from its
+   * pane can drop that much and paste flush. Claude Code indents two and puts its own
+   * markers in those columns.
+   *
+   * ⚠ DECLARED rather than measured off the pane, and two measured attempts are why.
+   * Asking whether the pane painted real spaces across the unused part of each row
+   * separates a TUI from a shell perfectly where it fires and never over-stripped; it
+   * is also a function of pane WIDTH, because that padding exists only while a
+   * rendered line stops short of the CLI's own layout width and Claude Code's prose
+   * wraps to fill it. On one live transcript the share of padded rows ran 44%, 6%, 6%,
+   * 7% and 87% at 123, 160, 198, 235 and 298 columns, so at any ordinary window size
+   * the strip silently did nothing. Taking the narrowest indent on the surrounding
+   * rows instead fires at every width and over-strips on roughly 1% of selections,
+   * because a file listing inside the transcript can be the narrowest thing on screen.
+   *
+   * A declared width can do neither. The strip is the lesser of this and what every
+   * selected line shares, so a block can only ever shift as a unit, and it can never
+   * shift further than the CLI itself says its gutter is.
+   *
+   * Absent means no strip at all, the same fail-safe direction `workDetect` takes.
+   */
+  transcriptGutter?: number;
   /** No direct-PTY fallback: the CLI must run inside tmux (secrets ride tmux setenv). */
   requiresMux: boolean;
   /**

src/web/public/constants.js

@@ -819,36 +819,32 @@ function decideAutoCopy({ enabled, text, lastCopied, pending } = {}) {
 // _selectTouchSelectionLine already treats those cells as padding. This is that
 // same rule for the mouse and keyboard paths, which never had it.
 //
-// ⚠ Trailing padding ONLY. A shared LEADING indent is deliberately left alone,
-// and this note is here so the idea is not re-derived: it was built, measured
-// and dropped before merge. Removing the longest leading run every selected row
-// shares looks like the mirror image of the trailing trim and is not, because
-// no native terminal does it and the transform cannot tell a TUI's margin from
-// content that is genuinely indented. Measured over 401 445 three-row windows
-// across 1 010 tracked files in this repo, it fired on 73% of them: 92% inside
-// a YAML workflow, 76% over `git log` output, 48% in a TypeScript source file.
-// No width threshold separates the two, because they are the same widths: a
-// live Claude Code pane's own margins measure 2 and 5 columns while the most
-// common non-TUI shared run is 4, sitting between them.
+// A LEADING margin is stripped too, but only the one the CLI in the pane
+// DECLARES as its transcript gutter, passed in as `options.margin`. Called with
+// no options this trims trailing padding and nothing else, which is what keeps
+// every caller that has no declared gutter on the old behaviour.
 //
-// The asymmetry that settles it is in the failure modes. A wrong trailing trim
+// ⚠ The failure modes are not symmetrical, and that asymmetry sets how much
+// evidence a leading strip has to show before it fires. A wrong trailing trim
 // costs nothing. A wrong dedent silently deletes information that was on the
 // screen, with no signal to the user and nothing in the clipboard to hint at
 // it, and it is wrong on `git log` bodies, on indented code read out of `cat`
 // (semantic in Python), on `git diff` context rows where the leading space is
 // the marker, and on stack traces.
 //
-// ⚠ It also cannot be made consistent cheaply. Whether the first row joins the
-// measurement depended on the mousedown COLUMN, which the user never sees, so
-// one block of three rows produced three different clipboard results; and the
-// flag read `getSelectionPosition().start`, which is the mousedown anchor that
-// xterm never normalises, so dragging UP through a block read it off the bottom
-// row. If it is ever revisited, the one qualification that measured clean is
-// painted trailing padding (a full-screen TUI writes real spaces across every
-// row; a shell pane leaves those cells never-written, so xterm trims them):
-// zero false positives over all 401 445 windows. It still mangles a `git log`
-// body sitting inside an agent's own gutter, which is why it was not taken now.
-function cleanCopiedSelection(text) {
+// ⚠ The declared gutter is a CEILING, not the answer. The strip is the lesser
+// of it and the run every selected line shares, so a block can only ever shift
+// as a unit: the relative structure inside a selection survives by
+// construction, and a selection reaching column 0 loses nothing at all.
+//
+// ⚠ Deriving the width from the text instead is what fails, twice over. The
+// selection's own shared indent cannot tell a margin from content, because a
+// three-row window of nested YAML shares an indent for the same reason a margin
+// does — it fired on 73% of ordinary indented text. Taking the narrowest indent
+// on the surrounding rows fails more quietly: a file listing inside the
+// transcript can be the narrowest thing on screen, which over-stripped about 1%
+// of selections across six pane widths.
+function cleanCopiedSelection(text, options) {
   if (typeof text !== 'string' || !text) return '';
   // Split on \n and leave any \r in place: xterm joins rows with \r\n on
   // Windows, and the clipboard should keep the endings xterm chose.
@@ -868,7 +864,36 @@ function cleanCopiedSelection(text) {
     while (cut > 0 && (line[cut - 1] === ' ' || line[cut - 1] === '\t')) cut--;
     return cut === end ? line : line.slice(0, cut) + line.slice(end);
   };
-  return text.split('\n').map(trimEnd).join('\n');
+  const lines = text.split('\n');
+  for (let i = 0; i < lines.length; i++) lines[i] = trimEnd(lines[i]);
+
+  const margin = Math.max(0, Math.trunc(Number(options?.margin) || 0));
+  if (!margin) return lines.join('\n');
+
+  // The first line of a selection that began mid-row carries no margin — the
+  // mousedown cut it off — so it neither votes on the shared indent nor gets
+  // stripped. This is the ONE thing the mousedown column still decides, and it
+  // decides it for that line alone. Whether the rest of the block is dedented
+  // no longer depends on where the click landed, which is what made the same
+  // three rows produce three different clipboard results before.
+  const from = options?.firstLinePartial === true ? 1 : 0;
+
+  // The pane's margin is a ceiling, not the answer. Strip the narrower of it
+  // and what every selected line shares, so the block shifts as a unit and no
+  // line can lose indentation another line keeps.
+  let shared = margin;
+  for (let i = from; i < lines.length && shared > 0; i++) {
+    const line = lines[i];
+    if (!line || line === '\r') continue; // a padding-only row, already trimmed away
+    let run = 0;
+    while (run < line.length && line[run] === ' ') run++;
+    if (run < shared) shared = run;
+  }
+  if (!shared) return lines.join('\n');
+  for (let i = from; i < lines.length; i++) {
+    if (lines[i] && lines[i] !== '\r') lines[i] = lines[i].slice(shared);
+  }
+  return lines.join('\n');
 }
 
 if (typeof window !== 'undefined') {

src/web/public/index.html

@@ -1791,6 +1791,13 @@
                     </div>
                     <label class="switch switch-sm"><input type="checkbox" id="appSettingsAutoCopySelection"><span class="slider"></span></label>
                   </div>
+                  <div class="set-row" data-search="copy indent margin gutter dedent trim leading whitespace paste">
+                    <div class="set-row-text">
+                      <span class="set-row-label">Trim the pane margin on copy</span>
+                      <span class="set-row-desc">Drop the left margin a full-screen agent CLI paints down its own edge, so copied text pastes flush instead of indented. Each CLI declares its own width, and the strip is never wider than the indent every selected line shares, so nesting inside the selection is kept. Claude Code and Codex declare a margin today; a shell, and any CLI that declares none, is left alone.</span>
+                    </div>
+                    <label class="switch switch-sm"><input type="checkbox" id="appSettingsCopyStripMargin"><span class="slider"></span></label>
+                  </div>
                 </div>
               </div>
 

src/web/public/settings-ui.js

@@ -446,6 +446,8 @@ Object.assign(CodemanApp.prototype, {
     // overwrites the system clipboard on a gesture the user may have meant only as
     // a way to read, so it is opt-in rather than a default anyone has to discover.
     document.getElementById('appSettingsAutoCopySelection').checked = settings.autoCopySelection === true;
+    // Default ON, so an absent key reads as enabled rather than as off.
+    document.getElementById('appSettingsCopyStripMargin').checked = settings.copyStripMargin !== false;
     document.getElementById('appSettingsTerminalFont').value = settings.terminalFontFamily || '';
     this.populateTerminalFontWeight(document.getElementById('appSettingsTerminalFontWeight'), settings.terminalFontWeight);
     this.populateTerminalFontWeight(
@@ -2137,6 +2139,7 @@ Object.assign(CodemanApp.prototype, {
       tunnelEnabled: document.getElementById('appSettingsTunnelEnabled').checked,
       localEchoEnabled: document.getElementById('appSettingsLocalEcho').checked,
       autoCopySelection: document.getElementById('appSettingsAutoCopySelection').checked,
+      copyStripMargin: document.getElementById('appSettingsCopyStripMargin').checked,
       terminalFontFamily: document.getElementById('appSettingsTerminalFont').value.trim(),
       terminalFontWeight: this.readTerminalFontWeight(document.getElementById('appSettingsTerminalFontWeight')),
       terminalFontWeightBold: this.readTerminalFontWeight(
@@ -2363,6 +2366,10 @@ Object.assign(CodemanApp.prototype, {
       // and absent from SettingsUpdateSchema (.strict()), so sending it would
       // 400 the whole settings PUT.
       autoCopySelection: _acs,
+      // What the clipboard gets is a property of what this device is looking
+      // at, and the key is absent from SettingsUpdateSchema (.strict()), so
+      // sending it would 400 the whole settings PUT.
+      copyStripMargin: _csm,
       // Per-device by nature (the font must exist on the device) and absent
       // from SettingsUpdateSchema (.strict()) — sending it would 400 the PUT.
       terminalFontFamily: _tff,
@@ -3372,7 +3379,7 @@ Object.assign(CodemanApp.prototype, {
           'terminalFontFamily', 'terminalFontWeight', 'terminalFontWeightBold',
           'language',
           'terminalWheelLocalScrollback',
-          'autoCopySelection',
+          'autoCopySelection', 'copyStripMargin',
           'showSessionButton', 'showAwayDigestButton', 'showCronButton',
           'showTabDetachButton',
           'mobileOverviewEnabled',

src/web/public/terminal-split.js

@@ -188,7 +188,18 @@
         if (ev.type === 'keydown' && global.app?.shouldCopyTerminalSelectionFromShortcut?.(ev)) {
           const raw = this.terminal?.getSelection?.() || '';
           const isColumnSelection = this.terminal?._core?._selectionService?._activeSelectionMode === 3;
-          const selection = isColumnSelection ? raw : (global.CodemanCopySelection?.clean?.(raw) ?? raw);
+          // Both clean options are read for THIS pane, never the primary one:
+          // the gutter width comes from this.sessionId's own run mode, and the
+          // partial-first-line flag from this terminal's own selection range.
+          // Passing neither left Pane B keeping a margin Pane A dropped, on the
+          // same split and the same keystroke.
+          const range = global.app?._normalisedSelectionRange?.(this.terminal);
+          const selection = isColumnSelection
+            ? raw
+            : (global.CodemanCopySelection?.clean?.(raw, {
+                margin: global.app?._cliGutterColumns?.(this.sessionId) ?? 0,
+                firstLinePartial: !!range && range.start.x > 0,
+              }) ?? raw);
           if (selection.trim()) {
             ev.preventDefault();
             void global.app._copyText?.(selection).then((ok) => {

src/web/public/terminal-ui.js

@@ -368,10 +368,18 @@ Object.assign(CodemanApp.prototype, {
         // part of a row selects real padding spaces, which are truthy, so testing
         // the raw text would spend this press on a copy of nothing and make the
         // user press again to interrupt.
-        const selection = this.cleanedTerminalSelection();
+        //
+        // ⚠️ The gate cleans, and the copy is handed the RAW selection, because
+        // copyTerminalSelection cleans again on its own. The margin strip is not
+        // idempotent: a second pass takes up to `margin` more columns off what
+        // the first pass left, so passing the cleaned string through dedented a
+        // Claude or Codex copy twice. Every other copy path already hands over
+        // the raw selection or reads it live.
+        const raw = this.terminal?.hasSelection?.() ? this.terminal.getSelection() : '';
+        const selection = this.cleanedTerminalSelection(raw);
         if (selection.trim()) {
           ev.preventDefault();
-          void this.copyTerminalSelection(selection);
+          void this.copyTerminalSelection(raw);
           return false;
         }
         // Nothing worth copying. The clear is for feedback, not for the
@@ -4168,11 +4176,16 @@ Object.assign(CodemanApp.prototype, {
    *
    * `text` is for the callers that already read the selection to decide whether
    * to copy at all (the Ctrl+C gate and the right-click handler), so the read is
-   * not repeated. The transform is idempotent on xterm output, so an
-   * already-cleaned string is an acceptable argument: a CR is consumed by the
-   * parser as a cursor move and never stored in a cell, so the only \r the
-   * selection can carry is the Windows line join, and that is what makes the
-   * trailing scan a fixed point. Fuzzed over 300 000 realistic selections.
+   * not repeated.
+   *
+   * ⚠️ **Pass the RAW selection, never an already-cleaned one.** The trailing
+   * trim alone is a fixed point, because a CR is consumed by the parser as a
+   * cursor move and never stored in a cell, so the only \r the selection can
+   * carry is the Windows line join. The MARGIN strip is not: it takes the
+   * narrower of the declared width and the run every line shares, so a second
+   * pass over an already-stripped block takes up to `margin` columns more. A
+   * caller that cleans to decide whether to copy must still hand the raw text
+   * to copyTerminalSelection, which cleans once on its own.
    *
    * A COLUMN selection comes back untouched. Alt+drag makes one (xterm's
    * shouldColumnSelect keys on altKey alone, and Codeman sets neither of the
@@ -4189,7 +4202,73 @@ Object.assign(CodemanApp.prototype, {
     if (this.terminal?._core?._selectionService?._activeSelectionMode === 3) return raw;
     const clean = window.CodemanCopySelection?.clean;
     if (!clean) return raw;
-    return clean(raw);
+    const range = this._normalisedSelectionRange();
+    return clean(raw, {
+      margin: this._cliGutterColumns(),
+      firstLinePartial: !!range && range.start.x > 0,
+    });
+  },
+
+  /**
+   * xterm's selection range with its two ends in reading order.
+   *
+   * `getSelectionPosition()` reports `start` and `end` as the two ends of the
+   * drag, and on xterm 6.0 it already hands back the earlier one first: it
+   * reads `_selectionService.selectionStart`, whose getter returns the model's
+   * `finalSelectionStart`, and that swaps the pair for a reversed selection.
+   * A real upward mouse drag through chromium confirms it. The ordering here
+   * is a guard rather than a fix. One layer down the same model exposes the
+   * UNNORMALISED fields under the same two names, and a reversed pair would
+   * make the row window below run backwards and collapse, which would report
+   * no margin at all for every upward drag in a deep buffer.
+   *
+   * `terminal` names which xterm to read, defaulting to the primary pane's.
+   * Pane B of a split owns a second terminal and passes it, because this file's
+   * `this` is always the primary pane.
+   */
+  _normalisedSelectionRange(terminal) {
+    const range = (terminal ?? this.terminal)?.getSelectionPosition?.();
+    if (!range?.start || !range?.end) return null;
+    const { start, end } = range;
+    const reversed = end.y < start.y || (end.y === start.y && end.x < start.x);
+    return reversed ? { start: end, end: start } : { start, end };
+  },
+
+  /**
+   * How many columns to take off a copy from one session's pane: the transcript
+   * gutter its CLI declares, or 0 when it declares none. `sessionId` defaults to
+   * the active session, and Pane B of a split passes its own, so both panes of a
+   * split strip the width their own CLI declares rather than Pane A's.
+   *
+   * ⚠️ Read from `window.__codemanTranscriptGutter`, the map the server derives
+   * from the `transcriptGutter` CAPABILITY at render time — never an id literal
+   * here, which is the registry's standing rule and is also what lets a CLI that
+   * declares a gutter later work with no change to this file.
+   *
+   * ⚠️ DECLARED rather than measured off the buffer, and two measured versions
+   * are why. Asking whether the pane painted spaces across the unused part of
+   * each row separates a TUI from a shell perfectly where it fires and never
+   * over-stripped, but it is a function of pane WIDTH, since that padding exists
+   * only while a rendered line stops short of the CLI's own layout width and
+   * Claude Code's prose wraps to fill it: the share of padded rows on one live
+   * transcript ran 44%, 6%, 6%, 7% and 87% at 123, 160, 198, 235 and 298
+   * columns, so the strip did nothing at any ordinary window size. Taking the
+   * narrowest indent on the rows around the selection instead fires at every
+   * width and over-strips on about 1% of them, because a file listing inside the
+   * transcript can be the narrowest thing on screen. A declared width does
+   * neither, and it reads no buffer rows at all on a path that runs on every
+   * Ctrl+C.
+   *
+   * A missing map means no session gets a strip, the same direction an
+   * unmeasured CLI takes by declaring nothing.
+   */
+  _cliGutterColumns(sessionId) {
+    if (!this._copyStripMarginEnabled()) return 0;
+    const byMode = window.__codemanTranscriptGutter;
+    if (!byMode || typeof byMode !== 'object') return 0;
+    const mode = this.sessions?.get(sessionId ?? this.activeSessionId)?.mode;
+    const columns = mode ? byMode[mode] : 0;
+    return Number.isInteger(columns) && columns > 0 ? columns : 0;
   },
 
   // Copy the current terminal selection. Goes through _copyText (Clipboard API,
@@ -4224,6 +4303,26 @@ Object.assign(CodemanApp.prototype, {
     return ok;
   },
 
+  /**
+   * Whether this device wants the pane's left margin off the clipboard
+   * (`copyStripMargin`, per-device, default ON).
+   *
+   * Read here rather than mirrored into a field, for the same reason
+   * `_autoCopySelectionEnabled` is: there is then no apply-path a future
+   * settings save can forget to call, and the toggle takes effect on the next
+   * selection instead of the next reload. ⚠️ The test is `!== false`, not
+   * `=== true`: this one defaults ON, and the desktop branch of
+   * getDefaultSettings returns {} and leans on the read sites for defaults, so
+   * a device that has never opened App Settings has no stored value at all.
+   */
+  _copyStripMarginEnabled() {
+    try {
+      return this.loadAppSettingsFromStorage?.()?.copyStripMargin !== false;
+    } catch {
+      return true;
+    }
+  },
+
   /**
    * Auto Copy's ON/OFF, read at flush time from the CACHED settings object
    * (loadAppSettingsFromStorage memoizes, so this is not a localStorage hit).

src/web/server.ts

@@ -1688,6 +1688,27 @@ export class WebServer extends EventEmitter {
         () => `<script>window.__codemanCustomModelClis=${customModelClisJson};</script>\n</head>`
       );
     }
+    // How many columns each run mode indents its transcript by, so a copy can drop
+    // that much. Read off `capabilities` like the payload above and never as an id
+    // list here, so a CLI that declares a gutter later needs no frontend change.
+    // Ids and small integers only, no user-settable strings, so JSON.stringify
+    // alone is enough (same reasoning as __codemanCliAvailable's booleans).
+    //
+    // ⚠️ Outside the `if (!soloSessionId)` block above, unlike every other payload
+    // here: a detached session window (`/session/:id`) runs a terminal, so Ctrl+C
+    // copies there, and an absent map reads as "no session gets a strip". The
+    // toggle used to work in the main window and do nothing in the popup on the
+    // same device. This needs no availability probe, so it costs a solo window
+    // nothing that the run menu's own payloads would have cost it.
+    const gutterClis: Record<string, number> = {};
+    for (const entry of enabledClis()) {
+      const columns = entry.capabilities.transcriptGutter;
+      if (typeof columns === 'number') gutterClis[entry.id] = columns;
+    }
+    html = html.replace(
+      '</head>',
+      () => `<script>window.__codemanTranscriptGutter=${JSON.stringify(gutterClis)};</script>\n</head>`
+    );
     if (!soloSessionId && process.env.CODEMAN_GESTURE === '1') {
       html = html.replace('</head>', () => `<script>window.__codemanGestureAvailable=true;</script>\n</head>`);
       if (settings.gestureControlEnabled === true) {