End DCS/OSC strings at any ESC, default the external terminal to Terminal.app

A string with no ST swallowed every later sequence, RIS included, and
Clear Screen could not recover the tab. Any ESC now ends it, as in xterm,
and the sequence it starts is dispatched. The shipped setting needed Kitty.

Also: REP, SCOSC/SCORC, DECOM-relative CPR, `:` subparams and more DECRQM
modes answered; new rows inserted in one edit; controls stripped from
pastes; wide-char mouse columns.

benchmarks/bench_vs_terminus.py

@@ -296,11 +296,12 @@ def drive(feed, need_to_render, render, data, tick):
 def run_vterm(data, tick):
     from vterm.emulator import VtScreen, VtStream
     from vterm.render import VtermRenderCommand
+    from vterm.scheme import get_scheme_manager
     from vterm.terminal import Terminal
 
     counter = collections.Counter()
     view = CountingView(counter)
-    terminal = Terminal(view)
+    terminal = Terminal(view, get_scheme_manager("default"))
     terminal.scrollback_size = SCROLLBACK
     terminal.process = FakeProcess()
     terminal.screen = VtScreen(COLUMNS, ROWS, process=terminal.process, history=SCROLLBACK)

tests/test_commands.py

@@ -4,7 +4,7 @@ import _bootstrap  # sets sys.path for the imports below
 from _bootstrap import FakeProcess
 
 import sublime
-from vterm.commands import VtermPasteSelectionCommand, VtermSelectThemeCommand, selection_text
+from vterm.commands import VtermPasteSelectionCommand, VtermPasteTextCommand, VtermSelectThemeCommand, selection_text
 from vterm.emulator import VtScreen
 from vterm.render import CONTINUATION
 from vterm.scheme import get_scheme_manager
@@ -245,3 +245,17 @@ view = FakeView("abcdef", [sublime.Region(2, 2)])
 assert paste(view) == [], view.commands
 
 print("selection tests passed (sentinel stripping, paste, empty no-op)")
+
+
+# a paste is a trust boundary: C0 controls bar tab/LF/CR go, so a pasted
+# ESC[201~ cannot close the bracket and type the rest into the app
+terminal = fake_terminal("default")
+terminal.process = terminal.screen._process
+terminal.screen.set_mode(2004, private=True)
+terminal.view.run_command = lambda name, args=None: None
+command = VtermPasteTextCommand.__new__(VtermPasteTextCommand)
+command.view = terminal.view
+command.run(None, "a\x1b[201~b\x00\tc\nd")
+assert terminal.process.written == "\x1b[200~a[201~b\tc\rd\x1b[201~", repr(terminal.process.written)
+
+print("paste tests passed (controls stripped, bracket kept whole)")

tests/test_emulator.py

@@ -454,8 +454,67 @@ def run_clear_cases():
     print("all clear-screen tests passed")
 
 
+def run_parser_edge_cases():
+    """Sequences the stock collector misread: intermediates, `:` subparams, REP, marks."""
+    for char_by_char in (False, True):
+        tag = "char-by-char" if char_by_char else "chunked"
+
+        # DECSTR (`reset` sends it): `!` is an intermediate, the `p` must not be drawn
+        proc, screen, stream = make(20, 4)
+        feed(stream, "\x1b[!pX", char_by_char)
+        assert screen.display[0].rstrip() == "X", (tag, repr(screen.display[0]))
+
+        # `4:3` is curly underline, not SGR 43 (yellow background)
+        proc, screen, stream = make(20, 4)
+        feed(stream, "\x1b[4:3mX\x1b[38:2:1:2:3mY", char_by_char)
+        cell = screen.buffer[0][0]
+        assert (cell.bg, cell.underscore) == ("default", True), (tag, cell)
+        assert screen.buffer[0][1].data == "Y", (tag, screen.buffer[0][1])
+
+        # REP repeats the last printable; ncurses emits it for runs
+        proc, screen, stream = make(20, 4)
+        feed(stream, "a\x1b[3b\x1b[31mb\x1b[b", char_by_char)
+        assert screen.display[0].rstrip() == "aaaabb", (tag, repr(screen.display[0]))
+        assert screen.buffer[0][5].fg == "red", (tag, screen.buffer[0][5])
+
+        # a Thai vowel sign has combining class 0 but is still a mark: merged, not dropped
+        proc, screen, stream = make(20, 4)
+        feed(stream, "\u0e01\u0e31x", char_by_char)
+        assert screen.buffer[0][0].data == "\u0e01\u0e31", (tag, screen.buffer[0][0])
+        assert screen.buffer[0][1].data == "x", (tag, screen.buffer[0][1])
+
+        # DECRQM: the modes we honour answer set/reset, never "unrecognized"
+        proc, screen, stream = make()
+        feed(stream, "\x1b[?2031$p\x1b[?1h\x1b[?1$p\x1b[4$p\x1b[20$p", char_by_char)
+        assert proc.written == "\x1b[?2031;2$y\x1b[?1;1$y\x1b[4;2$y\x1b[20;2$y", (tag, proc.written)
+
+        # RIS on the alternate screen lands back on a cleared primary screen
+        proc, screen, stream = make(20, 4)
+        feed(stream, "primary\x1b[?1049halt\x1bc", char_by_char)
+        assert not screen.alternate_buffer_mode and not screen.savepoints, tag
+        assert screen.display[0].strip() == "", (tag, repr(screen.display[0]))
+        feed(stream, "\r\n" * 4, char_by_char)
+        assert len(screen.history) == 1, (tag, len(screen.history))
+
+        # SCOSC/SCORC, and CPR relative to the region under DECOM
+        proc, screen, stream = make(20, 4)
+        feed(stream, "ab\x1b[s\x1b[3;3H\x1b[uX\x1b[2;3r\x1b[?6h\x1b[6n", char_by_char)
+        assert screen.display[0].rstrip() == "abX", (tag, repr(screen.display[0]))
+        assert proc.written == "\x1b[1;1R", (tag, proc.written)
+
+        # a string with no terminator ends at the next ESC, as in xterm; a stray
+        # ESC P from a binary must not swallow the rest of the session
+        proc, screen, stream = make(20, 4)
+        feed(stream, "\x1bPgarbage\x1bcX\x1b]0;title\x1b[1mY", char_by_char)
+        assert screen.display[0].rstrip() == "XY", (tag, repr(screen.display[0]))
+        assert screen.title == "title" and screen.buffer[0][1].bold, (tag, screen.title)
+
+    print("all parser edge-case tests passed")
+
+
 run_case(char_by_char=False)
 run_case(char_by_char=True)
+run_parser_edge_cases()
 run_clear_cases()
 run_resize_cases()
 run_private_csi_cases()

tests/test_render.py

@@ -357,7 +357,13 @@ command = make_command(terminal)
 stream.feed("".join("\x1b[31mr{}\x1b[0m\r\n".format(i) for i in range(300)))
 command.update_lines(None, terminal)
 terminal.screen.dirty.clear()
-assert set(command.state.archived_chunks) == {0}, command.state.archived_chunks
+# rows new to the view went in as one insert, coloured straight onto their
+# chunk keys; only row 0 and the two coloured screen rows have a key of their own
+assert set(command.state.archived_chunks) == {0, 1}, command.state.archived_chunks
+assert len(terminal.view.regions["vterm@1@vterm.red.default"][1]) == terminal.offset - CHUNK
+row_keys = [k for k in terminal.view.regions if k.startswith("vterm#")]
+assert len(row_keys) == 3, row_keys
+assert terminal.view.text.split("\n")[:3] == ["r0", "r1", "r2"], terminal.view.text[:20]
 command.trim_history(None, terminal)
 assert "vterm@0@vterm.red.default" not in terminal.view.regions, "trimmed chunk key left behind"
 assert 0 not in command.state.archived_chunks
@@ -665,7 +671,15 @@ terminal.view.window_to_text = lambda xy: terminal.view.text_point(2, 4)
 mouse_release.run(None, event)
 assert terminal.process.written == "\x1b[<0;1;1M\x1b[<32;5;3M\x1b[<0;5;3m", repr(terminal.process.written)
 
-print("click tests passed (first click focuses only; press, drag and release report)")
+# the column is counted in cells: a wide char before the point takes two
+terminal.process.writes.clear()
+terminal.view.text = "\u65e5\u672cx   \nr1    \nr2    \nr3    \nr4    \n"
+terminal.view.window_to_text = lambda xy: terminal.view.text_point(0, 2)
+mouse_press.run(None, event)
+mouse_release.run(None, event)
+assert terminal.process.written == "\x1b[<0;5;1M\x1b[<0;5;1m", repr(terminal.process.written)
+
+print("click tests passed (first click focuses only; press, drag and release report; wide chars)")
 
 
 # entering the alt screen folds the scrollback away (kitty hides it); leaving
@@ -751,4 +765,12 @@ line[0] = Char("r", "red", "default", False, False, False, False, True)
 runs = [r for r in segment_buffer_line(line) if r[1] != r[2]]
 assert runs == [("r", 0, 1, "reverse_default", "red", "")], runs
 
-print("segmenter tests passed (leading gap, wide char, orphan filler, reverse)")
+# a cell can hold two code points (a mark NFC could not compose): the spans
+# that follow are offsets into the row text, so they move by two
+line = StaticDefaultDict(Char(" "))
+line[0] = Char("q\u0301", "default", "default")
+line[1] = Char("x", "blue", "default")
+runs = [r for r in segment_buffer_line(line) if r[1] != r[2]]
+assert runs == [("q\u0301", 0, 2, "default", "default", ""), ("x", 2, 3, "blue", "default", "")], runs
+
+print("segmenter tests passed (leading gap, wide char, orphan filler, reverse, two-code-point cell)")

vterm.sublime-settings

@@ -33,12 +33,12 @@
 
     // External terminal for "vterm: Open Terminal in Project Folder".
     // %CWD% in parameters is replaced with the project folder.
-    // "terminal": "/usr/bin/open",
-    // "parameters": ["-a", "Terminal", "%CWD%"],
+    "terminal": "/usr/bin/open",
+    "parameters": ["-a", "Terminal", "%CWD%"],
 
     // kitty instead of Apple Terminal:
-    "terminal": "/usr/bin/open",
-    "parameters": ["-a", "Kitty", "%CWD%"],
+    // "terminal": "/usr/bin/open",
+    // "parameters": ["-a", "Kitty", "%CWD%"],
 
     "debug": false
 }

vterm/emulator.py

@@ -40,7 +40,7 @@ FG_AIXTERM = {90 + i: ANSI_COLORS[8 + i] for i in range(8)}
 BG_AIXTERM = {100 + i: ANSI_COLORS[8 + i] for i in range(8)}
 
 # DECRQM answers, as wire numbers (pyte stores modes shifted << 5)
-REPORTABLE_MODES = (mo.DECAWM >> 5, mo.DECTCEM >> 5, 1000, 1002, 1003, 1004, 1006, 1049, 2004, 2026)
+REPORTABLE_MODES = (1, mo.DECAWM >> 5, mo.DECTCEM >> 5, 1000, 1002, 1003, 1004, 1006, 1049, 2004, 2026, 2031)
 
 # DEC private modes, pre-shifted into pyte's internal representation.
 # 1: DECCKM, application cursor keys (arrows send SS3)
@@ -153,6 +153,8 @@ class VtScreen(pyte.Screen):
         self._char_caches = {}
         self._char_cache = {}
         self._cache_attrs = None
+        # last printable drawn, for REP
+        self._last_char = ""
         self.history = deque(maxlen=history)
         self.alternate_buffer_mode = False
         self._sync_frame_start = 0
@@ -165,11 +167,16 @@ class VtScreen(pyte.Screen):
 
     def reset(self):
         """RIS: reset the screen along with the cursor, scrollback and caches"""
+        if self.alternate_buffer_mode:
+            # the primary screen is what a reset clears; leave the alt one behind
+            self.reset_mode(1049, private=True)
         self._default_char = Char(data=" ", fg="default", bg="default", reverse=False)
         self._sgr_cache.clear()
         self._char_caches.clear()
         self._cache_attrs = None
+        self._last_char = ""
         super().reset()
+        self.savepoints = []
         self.cursor = Cursor(0, 0)
         self.cursor_style = 0
         self.modify_other_keys = 0
@@ -376,6 +383,7 @@ class VtScreen(pyte.Screen):
                 dirty.add(cursor.y)
                 cursor.x = x + take
                 pos = end
+            self._last_char = data[-1]
             return
 
         line = buffer[cursor.y]
@@ -400,6 +408,7 @@ class VtScreen(pyte.Screen):
                 if cell is None:
                     cell = cache[char] = attrs._replace(data=char)
                 line[cursor.x] = cell
+                self._last_char = char
                 if char_width == 2 and cursor.x + 1 < columns:
                     filler = cache.get("")
                     if filler is None:
@@ -407,7 +416,10 @@ class VtScreen(pyte.Screen):
                     line[cursor.x + 1] = filler
             # a combining mark belongs to the cell before it, which may be the
             # last column of the previous row
-            elif char_width == 0 and unicodedata.combining(char):
+            # a mark: by category, not combining(), which is 0 for Thai/Indic
+            # vowel signs. Variation selectors are marks too but stay dropped:
+            # merged, VS16 would make the cell width 2 and swallow its neighbour
+            elif char_width == 0 and unicodedata.category(char)[0] == "M" and not "\ufe00" <= char <= "\ufe0f":
                 # sublime renders decomposed combining chars poorly; merge as NFC
                 pos = None
                 last = None
@@ -439,6 +451,11 @@ class VtScreen(pyte.Screen):
 
         self.dirty.add(cursor.y)
 
+    def repeat_character(self, count=None):
+        """REP: draw the last printable again `count` times."""
+        if self._last_char:
+            self.draw(self._last_char * (count or 1))
+
     def index(self):
         """Line feed; at the bottom of the primary screen the top row goes to scrollback."""
         # a region spanning the whole screen (CSI 1;<lines> r) is no region
@@ -615,6 +632,8 @@ class VtScreen(pyte.Screen):
         elif mode == 6:
             x = min(self.cursor.x, self.columns - 1) + 1
             y = self.cursor.y + 1
+            if mo.DECOM in self.mode and self.margins:
+                y -= self.margins.top
             marker = "?" if private else ""
             self.write_process_input("\x1b[{}{};{}R".format(marker, y, x))
         elif mode == 996 and private:
@@ -632,7 +651,10 @@ class VtScreen(pyte.Screen):
     def report_mode_status(self, mode, private):
         """DECRQM: answer 1 set, 2 reset, 0 for modes we do not implement."""
         if not private:
-            self.write_process_input("\x1b[{};0$y".format(mode))
+            value = 0
+            if mode in (mo.IRM, mo.LNM):
+                value = 1 if mode in self.mode else 2
+            self.write_process_input("\x1b[{};{}$y".format(mode, value))
             return
         if mode in REPORTABLE_MODES:
             value = 1 if (mode << 5) in self.mode else 2
@@ -683,6 +705,9 @@ class VtStream(pyte.Stream):
         self.csi = dict(self.csi)
         self.csi["S"] = "scroll_up"
         self.csi["T"] = "scroll_down"
+        self.csi["b"] = "repeat_character"
+        self.csi["s"] = "save_cursor"
+        self.csi["u"] = "restore_cursor"
         self._carry = ""
         # param-string -> parsed tuple; SGR strings repeat across a whole frame
         self._params_cache = {}
@@ -746,7 +771,8 @@ class VtStream(pyte.Stream):
                         raw = match.group(1)
                         params = cache.get(raw)
                         if params is None:
-                            params = tuple(min(int(p), 9999) if p else 0 for p in raw.split(";"))
+                            # no parameters is (), not (0,): save_cursor takes none
+                            params = tuple(min(int(p), 9999) if p else 0 for p in raw.split(";")) if raw else ()
                             if len(cache) > 4096:
                                 cache.clear()
                             cache[raw] = params
@@ -805,24 +831,33 @@ class VtStream(pyte.Stream):
         escape_dispatch = create_dispatcher(self.escape)
         csi_dispatch = create_dispatcher(self.csi)
 
+        # the byte after an ESC that cut a string short: any ESC ends a string,
+        # as in xterm, or one with no ST would swallow every later sequence
+        pending = None
         while True:
-            char = yield True
+            char = (yield True) if pending is None else ESC
 
             # ESC introducer: fold the 7-bit forms onto their C1 equivalents
             if char == ESC:
+                if pending is None:
                     char = yield None
+                else:
+                    char, pending = pending, None
                 if char == "[":
                     char = CSI_C1
                 elif char == "]":
                     char = OSC_C1
                 elif char in "PX^_":
                     # consume the payload so it never reaches the screen
-                    prev = ""
                     while True:
                         c = yield None
-                        if c == ctrl.ST_C1 or (prev == ESC and c == "\\"):
+                        if c == ESC:
+                            c = yield None
+                            if c != "\\":
+                                pending = c
+                            break
+                        if c == ctrl.ST_C1:
                             break
-                        prev = c
                     continue
                 else:
                     if char == "#":
@@ -848,13 +883,15 @@ class VtStream(pyte.Stream):
                 private = False
                 prefix = ""
                 intermediate = ""
+                # inside a `:` subparameter list, which is dropped (4:3 must not read as 43)
+                sub = False
                 while True:
                     char = yield None
                     if char == "?":
                         private = True
                     elif char in "><=":
                         prefix = char
-                    elif char in " $":
+                    elif " " <= char <= "/":
                         intermediate = char
                     elif char in ALLOWED_IN_CSI:
                         basic_dispatch[char]()
@@ -862,14 +899,16 @@ class VtStream(pyte.Stream):
                         draw(char)
                         break
                     elif char.isdigit():
+                        if not sub:
                             current += char
                     elif char == ":":
-                        # SGR subparameters, which we do not support
-                        pass
+                        sub = True
                     elif char == ";":
                         params.append(min(int(current or 0), 9999))
                         current = ""
+                        sub = False
                     else:
+                        if current or params:
                             params.append(min(int(current or 0), 9999))
                         self._dispatch_csi(csi_dispatch, listener, char, params, private, prefix, intermediate)
                         break
@@ -885,18 +924,19 @@ class VtStream(pyte.Stream):
                         break
 
                 payload = ""
-                if char == ";" or (char not in OSC_TERMINATORS and char != ESC):
-                    while True:
+                if char == ";":
                     char = yield None
+                while char not in OSC_TERMINATORS:
                     if char == ESC:
-                            char += yield None
-                        if char in OSC_TERMINATORS:
+                        char = yield None
+                        if char != "\\":
+                            pending = char
+                        # char holds the whole terminator, ST for a cut string
+                        char = ctrl.ST_C0
                         break
                     if len(payload) < MAX_OSC:
                         payload += char
-                elif char == ESC:
-                    # take the '\' of ST, so char holds the whole terminator
-                    char += yield None
+                    char = yield None
 
                 try:
                     listener.handle_osc(int(code or 0), payload, char)

vterm/mouse.py

@@ -5,7 +5,9 @@ The trackpad is not handled here. On macOS it never reaches a mousemap binding
 continuous scrolling into discrete wheel events; those arrive as ordinary wheel
 notches and take the path below.
 """
+import sublime
 import sublime_plugin
+from wcwidth import wcswidth
 
 from .terminal import Terminal
 from .utils import settings
@@ -41,6 +43,7 @@ def _event_to_cell(view, terminal, event, clamp=False):
     wheel and a release still belong to the app there, a press does not."""
     pt = view.window_to_text((event["x"], event["y"]))
     row, col = view.rowcol(pt)
+    col = wcswidth(view.substr(sublime.Region(pt - col, pt)))
     row -= terminal.offset
     screen = terminal.screen
     if row < 0 or row >= screen.lines:

vterm/render.py

@@ -1,11 +1,13 @@
 """ Rendering the emulator screen into the Sublime view
 
 The view holds real text: scrollback above `terminal.offset`, the live screen
-window from `offset` on. Dirty rows are whole-line replaced; colors are
-add_regions overlays with scopes served by the dynamic scheme. The ST caret
+window from `offset` on. Dirty rows are whole-line replaced, and rows the view
+does not hold yet are appended in one insert; colors are add_regions overlays
+with scopes served by the dynamic scheme. The ST caret
 doubles as the terminal cursor.
 """
 import math
+from bisect import bisect_left
 from functools import lru_cache
 
 import sublime
@@ -88,8 +90,10 @@ def segment_buffer_line(buffer_line):
 
         # an orphaned wide-char filler (its first half was overwritten) still
         # occupies a column; render a space so later spans stay aligned
-        run.append(char.data or " ")
-        column += 1
+        data = char.data
+        run.append(data or " ")
+        # a cell can hold more than one code point: a mark NFC could not compose
+        column += len(data) or 1
 
     if attrs is not None:
         yield _run(run, start, column, attrs)
@@ -304,23 +308,33 @@ class VtermRenderCommand(sublime_plugin.TextCommand):
         # valid for this method only; the trim paths erase rows
         self._lastrow = self.view.rowcol(self.view.size())[0]
         if dirty_lines:
-            # history pops newest-first, so it fills the rows below `offset` backwards
             history = screen.history
             popped = len(history)
             terminal.offset += popped
             offset = terminal.offset
+            first = offset - popped
+            retired = list(history)
+            history.clear()
 
-            for line in range(popped):
-                buffer_line = history.pop()
-                self.update_line(edit, offset - line - 1, buffer_line, columns)
+            # rows the view already holds are rewritten one by one; the rest
+            # are new and go in as one insert, after those edits moved the end
+            split = min(popped, self._lastrow + 1 - first)
+            for i in range(split):
+                self.update_line(edit, first + i, retired[i], columns)
+            if split < popped:
+                self.append_rows(edit, retired[split:], columns, scrollback=True)
 
-            # after the loop: a pop edits an earlier point than the one before
-            # it, so spans measured mid-loop would be stale
-            self.archive_rows(range(offset - popped, offset))
+            # after the edits: spans measured mid-loop would be stale
+            self.archive_rows(range(first, offset))
 
-            for line in dirty_lines:
-                buffer_line = screen.buffer[line]
-                self.update_line(edit, line + offset, buffer_line, columns)
+            # screen rows past the view's end go in as one insert too
+            start = self._lastrow + 1 - offset
+            cut = bisect_left(dirty_lines, start)
+            for line in dirty_lines[:cut]:
+                self.update_line(edit, line + offset, screen.buffer[line], columns)
+            if cut < len(dirty_lines):
+                rows = range(start, dirty_lines[-1] + 1)
+                self.append_rows(edit, [screen.buffer[y] for y in rows], columns, scrollback=False)
 
     def update_line(self, edit, line, buffer_line, columns):
         """Rewrite one view row from a screen row, unless it is unchanged"""
@@ -333,7 +347,17 @@ class VtermRenderCommand(sublime_plugin.TextCommand):
         if self.state.row_cache.get(line) == rendered:
             return
         self.state.row_cache[line] = rendered
+        text, by_scope = self.row_text(segments, lf)
 
+        self.ensure_row(edit, line)
+        line_region = view.line(view.text_point(line, 0))
+        self.decolorize_line(line)
+        view.replace(edit, line_region, text)
+        # replacing a line cannot move its start
+        self.colorize_line(line, line_region.begin(), by_scope)
+
+    def row_text(self, segments, lf):
+        """The view text of a row and its colour spans by scope, as char offsets."""
         by_scope = {}
         needed = 0
         scope_of = self._scheme.scope
@@ -350,13 +374,54 @@ class VtermRenderCommand(sublime_plugin.TextCommand):
         if len(text) < needed:
             # pad only to the last coloured run, in the same edit as the text
             text += " " * (needed - len(text))
+        return text, by_scope
 
-        self.ensure_row(edit, line)
-        line_region = view.line(view.text_point(line, 0))
-        self.decolorize_line(line)
-        view.replace(edit, line_region, text)
-        # replacing a line cannot move its start
-        self.colorize_line(line, line_region.begin(), by_scope)
+    def append_rows(self, edit, buffer_lines, columns, scrollback):
+        """Add rows below the view's end in one insert.
+
+        Scrollback rows are never rewritten, so their colours go straight onto
+        the chunk keys with no per-row key for flush_chunk to merge. Screen
+        rows are coloured per row as usual; a trailing blank run the trim
+        already erased is still cached as rendered and is left out.
+        """
+        view = self.view
+        rows = [(line, list(segment_buffer_line(buffer_line)), buffer_line[columns - 1].linefeed)
+                for line, buffer_line in enumerate(buffer_lines, self._lastrow + 1)]
+        if not scrollback:
+            while rows and self.state.row_cache.get(rows[-1][0]) == rows[-1][1:]:
+                rows.pop()
+            if not rows:
+                return
+
+        point = view.size() + 1
+        texts = []
+        # scrollback: (chunk, scope) -> regions; screen: (line, start, by_scope)
+        painted = {}
+        colored = []
+        trimmed = self.state.trimmed
+        for line, segments, lf in rows:
+            self.state.row_cache[line] = (segments, lf)
+            text, by_scope = self.row_text(segments, lf)
+            texts.append(text)
+            if scrollback:
+                chunk = (line + trimmed) // CHUNK
+                for scope, spans in by_scope.items():
+                    painted.setdefault((chunk, scope), []).extend(sublime.Region(point + a, point + b) for a, b in spans)
+            elif by_scope:
+                colored.append((line, point, by_scope))
+            point += len(text) + 1
+        view.insert(edit, view.size(), "\n" + "\n".join(texts))
+        self._lastrow = rows[-1][0]
+
+        for (chunk, scope), regions in painted.items():
+            key = chunk_key(chunk, scope)
+            scopes = self.state.archived_chunks.setdefault(chunk, set())
+            if scope in scopes:
+                regions = view.get_regions(key) + regions
+            view.add_regions(key, regions, scope)
+            scopes.add(scope)
+        for line, start, by_scope in colored:
+            self.colorize_line(line, start, by_scope)
 
     def colorize_line(self, line, line_start, by_scope):
         """Lay the colour overlays for one row, one add_regions per scope."""

vterm/terminal.py

@@ -2,6 +2,7 @@
 import codecs
 import logging
 import os
+import re
 import threading
 import time
 from collections import deque
@@ -40,6 +41,10 @@ IDLE_TICK = 0.2
 # a millisecond apart, and drawing between them flashes its showcmd echo
 SETTLE = 0.005
 
+# C0 controls bar tab/LF/CR, stripped from text sent as typed: a pasted
+# ESC[201~ would end the bracket early and type the rest into the app
+CONTROL_CHARS = re.compile("[\x00-\x08\x0b\x0c\x0e-\x1f\x7f]")
+
 # frames between undo-stack clears: every render edit lands on the view's undo
 # stack, which only focus changes clear otherwise, and undo is swallowed anyway
 UNDO_CLEAR_FRAMES = 100
@@ -394,7 +399,7 @@ class Terminal:
         # escape sequences go through untouched; typed and pasted text has its
         # line endings canonicalised for the app's LNM setting
         if normalized:
-            string = string.replace("\r\n", "\n")
+            string = CONTROL_CHARS.sub("", string).replace("\r\n", "\n")
             if mo.LNM in self.screen.mode:
                 string = string.replace("\n", "\r\n")
             else: