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fix(console): arrow keys and layout in modern renderer

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Two bugs fixed:

1. Arrow keys detected as ESC: sys.stdin.read(1) uses Python's internal
   buffer, so after reading ESC byte, the remaining escape sequence
   bytes ([A for up-arrow) were in Python's buffer but not visible to
   select.select() on the OS fd. Switched to os.read(fd, 1) which
   reads directly from the file descriptor, bypassing Python's buffer.

2. Footer positioned wrong: draw_footer() counted buffer items to
   calculate padding, but a Rich Table renders as multiple lines.
   Added _line_count tracker with _add_line() and _add_lines(n) so
   footer padding is calculated from actual rendered line count.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
This commit is contained in:
consultoria-as
2026-02-15 02:29:32 +00:00
parent 8c7caf3969
commit a3aa2a7608
1 changed files with 152 additions and 130 deletions
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282
console/renderers/textual_renderer.py
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@@ -4,6 +4,9 @@ Rich-based modern renderer for the AUTOPARTES console application.
Implements :class:`BaseRenderer` using the ``rich`` library for a modern Implements :class:`BaseRenderer` using the ``rich`` library for a modern
dark-themed TUI with blue/cyan accents. Uses alternate screen buffer dark-themed TUI with blue/cyan accents. Uses alternate screen buffer
and buffered output for flicker-free rendering. and buffered output for flicker-free rendering.
Key input uses os.read() on the raw fd to bypass Python's stdin buffer,
which ensures escape sequences (arrow keys, F-keys) are read correctly.
""" """
import os import os
@@ -33,15 +36,17 @@ class TextualRenderer(BaseRenderer):
self._old_term_settings = None self._old_term_settings = None
self._width = 80 self._width = 80
self._height = 24 self._height = 24
self._buffer = [] # list of Rich renderables per render cycle self._fd = -1
self._buffer = [] # list of Rich renderables per render cycle
self._line_count = 0 # track actual lines consumed by buffer
# ── Lifecycle ──────────────────────────────────────────────────── # ── Lifecycle ────────────────────────────────────────────────────
def init_screen(self): def init_screen(self):
"""Enter alternate screen, hide cursor, set persistent raw mode.""" """Enter alternate screen, hide cursor, set persistent raw mode."""
fd = sys.stdin.fileno() self._fd = sys.stdin.fileno()
try: try:
self._old_term_settings = termios.tcgetattr(fd) self._old_term_settings = termios.tcgetattr(self._fd)
except (termios.error, ValueError, OSError): except (termios.error, ValueError, OSError):
self._old_term_settings = None self._old_term_settings = None
@@ -51,7 +56,7 @@ class TextualRenderer(BaseRenderer):
# Set raw mode once for the entire session # Set raw mode once for the entire session
try: try:
tty.setraw(fd) tty.setraw(self._fd)
except termios.error: except termios.error:
pass pass
@@ -63,8 +68,7 @@ class TextualRenderer(BaseRenderer):
# Restore original terminal attributes # Restore original terminal attributes
if self._old_term_settings is not None: if self._old_term_settings is not None:
try: try:
fd = sys.stdin.fileno() termios.tcsetattr(self._fd, termios.TCSADRAIN,
termios.tcsetattr(fd, termios.TCSADRAIN,
self._old_term_settings) self._old_term_settings)
except (termios.error, ValueError, OSError): except (termios.error, ValueError, OSError):
pass pass
@@ -87,10 +91,20 @@ class TextualRenderer(BaseRenderer):
except OSError: except OSError:
pass pass
self._buffer = [] self._buffer = []
self._line_count = 0
def _add_line(self, renderable):
"""Add a single-line renderable to the buffer."""
self._buffer.append(renderable)
self._line_count += 1
def _add_lines(self, renderable, line_count):
"""Add a multi-line renderable (like a Table) to the buffer."""
self._buffer.append(renderable)
self._line_count += line_count
def refresh(self): def refresh(self):
"""Flush the entire buffered output to screen in one write.""" """Flush the entire buffered output to screen in one write."""
# Render all buffered content to a string via Rich
sio = StringIO() sio = StringIO()
console = Console( console = Console(
file=sio, file=sio,
@@ -100,10 +114,7 @@ class TextualRenderer(BaseRenderer):
color_system="truecolor", color_system="truecolor",
) )
for item in self._buffer: for item in self._buffer:
if isinstance(item, str): console.print(item, end="", highlight=False)
console.print(item, end="", highlight=False)
else:
console.print(item, end="", highlight=False)
rendered = sio.getvalue() rendered = sio.getvalue()
@@ -111,82 +122,100 @@ class TextualRenderer(BaseRenderer):
sys.stdout.write(f"\033[H\033[2J{rendered}") sys.stdout.write(f"\033[H\033[2J{rendered}")
sys.stdout.flush() sys.stdout.flush()
def get_key(self) -> int: # ── Key input (uses os.read to bypass Python stdin buffer) ──────
"""Read a key (terminal is already in raw mode)."""
fd = sys.stdin.fileno()
ch = sys.stdin.read(1)
if ch == "\x1b": def _read_byte(self) -> bytes:
if _has_data(fd): """Read exactly one byte from the raw fd."""
ch2 = sys.stdin.read(1) return os.read(self._fd, 1)
if ch2 == "[":
return self._parse_csi(fd) def _has_data(self, timeout=0.02) -> bool:
elif ch2 == "O": """Return True if there is data waiting on the fd."""
return self._parse_ss3(fd) r, _, _ = select.select([self._fd], [], [], timeout)
return bool(r)
def get_key(self) -> int:
"""Read a key using os.read() to bypass Python's stdin buffer."""
b = self._read_byte()
ch = b[0] if b else 0
if ch == 0x1b: # ESC
if self._has_data():
b2 = self._read_byte()
ch2 = b2[0] if b2 else 0
if ch2 == 0x5b: # [
return self._parse_csi()
elif ch2 == 0x4f: # O
return self._parse_ss3()
# Drain unknown escape # Drain unknown escape
while _has_data(fd): while self._has_data():
sys.stdin.read(1) self._read_byte()
return Key.ESCAPE return Key.ESCAPE
return Key.ESCAPE return Key.ESCAPE
if ch == "\r" or ch == "\n": if ch == 0x0d or ch == 0x0a: # CR or LF
return Key.ENTER return Key.ENTER
if ch == "\t": if ch == 0x09: # TAB
return Key.TAB return Key.TAB
if ch == "\x7f" or ch == "\x08": if ch == 0x7f or ch == 0x08: # DEL or BS
return Key.BACKSPACE return Key.BACKSPACE
if ch == "\x03": if ch == 0x03: # Ctrl-C
return Key.ESCAPE return Key.ESCAPE
return ord(ch) return ch
def _parse_csi(self, fd): def _read_one(self) -> int:
"""Read one byte and return as int."""
b = self._read_byte()
return b[0] if b else 0
def _parse_csi(self):
"""Parse CSI escape sequence (ESC [ ...).""" """Parse CSI escape sequence (ESC [ ...)."""
ch3 = sys.stdin.read(1) ch3 = self._read_one()
if ch3 == "A": return Key.UP if ch3 == 0x41: return Key.UP # A
if ch3 == "B": return Key.DOWN if ch3 == 0x42: return Key.DOWN # B
if ch3 == "C": return Key.RIGHT if ch3 == 0x43: return Key.RIGHT # C
if ch3 == "D": return Key.LEFT if ch3 == 0x44: return Key.LEFT # D
if ch3 == "H": return Key.HOME if ch3 == 0x48: return Key.HOME # H
if ch3 == "F": return Key.END if ch3 == 0x46: return Key.END # F
if ch3 == "5": if ch3 == 0x35: # 5
sys.stdin.read(1) # ~ self._read_one() # ~
return Key.PGUP return Key.PGUP
if ch3 == "6": if ch3 == 0x36: # 6
sys.stdin.read(1) # ~ self._read_one() # ~
return Key.PGDN return Key.PGDN
if ch3 == "1": if ch3 == 0x31: # 1
ch4 = sys.stdin.read(1) ch4 = self._read_one()
if ch4 == "~": return Key.HOME if ch4 == 0x7e: return Key.HOME # 1~
if ch4 == "5": sys.stdin.read(1); return Key.F5 if ch4 == 0x35: self._read_one(); return Key.F5 # 15~
if ch4 == "7": sys.stdin.read(1); return Key.F6 if ch4 == 0x37: self._read_one(); return Key.F6 # 17~
if ch4 == "8": sys.stdin.read(1); return Key.F7 if ch4 == 0x38: self._read_one(); return Key.F7 # 18~
if ch4 == "9": sys.stdin.read(1); return Key.F8 if ch4 == 0x39: self._read_one(); return Key.F8 # 19~
if _has_data(fd): sys.stdin.read(1) if self._has_data(): self._read_one()
return Key.HOME return Key.HOME
if ch3 == "2": if ch3 == 0x32: # 2
ch4 = sys.stdin.read(1) ch4 = self._read_one()
if ch4 == "0": sys.stdin.read(1); return Key.F9 if ch4 == 0x30: self._read_one(); return Key.F9 # 20~
if ch4 == "1": sys.stdin.read(1); return Key.F10 if ch4 == 0x31: self._read_one(); return Key.F10 # 21~
return Key.ESCAPE return Key.ESCAPE
if ch3 == "3": if ch3 == 0x33: # 3 (Delete)
if _has_data(fd): sys.stdin.read(1) if self._has_data(): self._read_one()
return Key.BACKSPACE return Key.BACKSPACE
if ch3 == "4": if ch3 == 0x34: # 4
if _has_data(fd): sys.stdin.read(1) if self._has_data(): self._read_one()
return Key.END return Key.END
while _has_data(fd): # Drain remaining
sys.stdin.read(1) while self._has_data():
self._read_one()
return Key.ESCAPE return Key.ESCAPE
def _parse_ss3(self, fd): def _parse_ss3(self):
"""Parse SS3 escape sequence (ESC O ...).""" """Parse SS3 escape sequence (ESC O ...)."""
ch3 = sys.stdin.read(1) ch3 = self._read_one()
if ch3 == "P": return Key.F1 if ch3 == 0x50: return Key.F1 # P
if ch3 == "Q": return Key.F2 if ch3 == 0x51: return Key.F2 # Q
if ch3 == "R": return Key.F3 if ch3 == 0x52: return Key.F3 # R
if ch3 == "S": return Key.F4 if ch3 == 0x53: return Key.F4 # S
if ch3 == "H": return Key.HOME if ch3 == 0x48: return Key.HOME # H
if ch3 == "F": return Key.END if ch3 == 0x46: return Key.END # F
return Key.ESCAPE return Key.ESCAPE
# ── High-level widgets ─────────────────────────────────────────── # ── High-level widgets ───────────────────────────────────────────
@@ -203,18 +232,17 @@ class TextualRenderer(BaseRenderer):
if header.cell_len < w: if header.cell_len < w:
header.append(" " * (w - header.cell_len)) header.append(" " * (w - header.cell_len))
header.stylize("on rgb(20,40,80)") header.stylize("on rgb(20,40,80)")
self._buffer.append(header) self._add_line(header)
self._buffer.append(Text("─" * w, style="blue")) self._add_line(Text("─" * w, style="blue"))
def draw_footer(self, key_labels): def draw_footer(self, key_labels):
h, w = self.get_size() h, w = self.get_size()
# Pad remaining space before footer # Pad remaining lines to push footer to bottom
used = len(self._buffer) remaining = h - self._line_count - 2 # 2 = separator + footer
remaining = h - used - 2 # 2 lines for separator + footer
for _ in range(max(remaining, 0)): for _ in range(max(remaining, 0)):
self._buffer.append(Text("")) self._add_line(Text(""))
self._buffer.append(Text("─" * w, style="blue")) self._add_line(Text("─" * w, style="blue"))
footer = Text() footer = Text()
for i, (key, desc) in enumerate(key_labels): for i, (key, desc) in enumerate(key_labels):
if i > 0: if i > 0:
@@ -226,15 +254,15 @@ class TextualRenderer(BaseRenderer):
" " * (w - footer.cell_len), " " * (w - footer.cell_len),
style="on rgb(20,40,80)", style="on rgb(20,40,80)",
) )
self._buffer.append(footer) self._add_line(footer)
def draw_menu(self, items, selected_index=0, title=''): def draw_menu(self, items, selected_index=0, title=''):
h, w = self.get_size() h, w = self.get_size()
visible_lines = h - 6 visible_lines = h - 6
if title: if title:
self._buffer.append(Text(f" {title}", style="bold white")) self._add_line(Text(f" {title}", style="bold white"))
self._buffer.append(Text("")) self._add_line(Text(""))
visible_lines -= 2 visible_lines -= 2
if visible_lines < 1: if visible_lines < 1:
@@ -252,7 +280,7 @@ class TextualRenderer(BaseRenderer):
continue continue
if num == "\u2500" or num == "---": if num == "\u2500" or num == "---":
self._buffer.append( self._add_line(
Text(" " + "─" * (w - 4), style="dim blue") Text(" " + "─" * (w - 4), style="dim blue")
) )
drawn += 1 drawn += 1
@@ -261,11 +289,11 @@ class TextualRenderer(BaseRenderer):
marker = "\u25b8 " if idx == selected_index else " " marker = "\u25b8 " if idx == selected_index else " "
if idx == selected_index: if idx == selected_index:
entry = pad_right(f"{marker}{num}. {label}", w - 4) entry = pad_right(f"{marker}{num}. {label}", w - 4)
self._buffer.append( self._add_line(
Text(f" {entry}", style="bold white on rgb(30,60,120)") Text(f" {entry}", style="bold white on rgb(30,60,120)")
) )
else: else:
self._buffer.append( self._add_line(
Text(f" {marker}{num}. {label}", style="white") Text(f" {marker}{num}. {label}", style="white")
) )
drawn += 1 drawn += 1
@@ -292,6 +320,7 @@ class TextualRenderer(BaseRenderer):
if visible < 1: if visible < 1:
visible = 1 visible = 1
actual_rows = 0
for i, row_data in enumerate(rows): for i, row_data in enumerate(rows):
if i >= visible: if i >= visible:
break break
@@ -299,14 +328,16 @@ class TextualRenderer(BaseRenderer):
row_style = ("bold white on rgb(30,60,120)" row_style = ("bold white on rgb(30,60,120)"
if i == selected_row else None) if i == selected_row else None)
table.add_row(str(i + 1), *cells, style=row_style) table.add_row(str(i + 1), *cells, style=row_style)
actual_rows += 1
self._buffer.append(table) # Table renders: 1 header + 1 separator + actual_rows
self._add_lines(table, actual_rows + 2)
if page_info: if page_info:
page = page_info.get("page", 1) page = page_info.get("page", 1)
total = page_info.get("total_pages", 1) total = page_info.get("total_pages", 1)
total_rows = page_info.get("total_rows", len(rows)) total_rows = page_info.get("total_rows", len(rows))
self._buffer.append(Text( self._add_line(Text(
f" Pagina {page}/{total} ({total_rows} registros)", f" Pagina {page}/{total} ({total_rows} registros)",
style="dim cyan", style="dim cyan",
)) ))
@@ -315,9 +346,9 @@ class TextualRenderer(BaseRenderer):
h, w = self.get_size() h, w = self.get_size()
if title: if title:
self._buffer.append(Text(f" {title}", style="bold white")) self._add_line(Text(f" {title}", style="bold white"))
self._buffer.append(Text(" " + "─" * (w - 4), style="blue")) self._add_line(Text(" " + "─" * (w - 4), style="blue"))
self._buffer.append(Text("")) self._add_line(Text(""))
max_label = max((len(lbl) for lbl, _ in fields), default=10) max_label = max((len(lbl) for lbl, _ in fields), default=10)
dot_total = max_label + 4 dot_total = max_label + 4
@@ -330,15 +361,15 @@ class TextualRenderer(BaseRenderer):
line = Text() line = Text()
line.append(f" {label}{dots}: ", style="cyan") line.append(f" {label}{dots}: ", style="cyan")
line.append(str(value), style="bold white") line.append(str(value), style="bold white")
self._buffer.append(line) self._add_line(line)
def draw_form(self, fields, focused_index=0, title=''): def draw_form(self, fields, focused_index=0, title=''):
h, w = self.get_size() h, w = self.get_size()
if title: if title:
self._buffer.append(Text(f" {title}", style="bold white")) self._add_line(Text(f" {title}", style="bold white"))
self._buffer.append(Text(" " + "─" * (w - 4), style="blue")) self._add_line(Text(" " + "─" * (w - 4), style="blue"))
self._buffer.append(Text("")) self._add_line(Text(""))
max_label = max((len(f.get("label", "")) for f in fields), default=10) max_label = max((len(f.get("label", "")) for f in fields), default=10)
dot_total = max_label + 4 dot_total = max_label + 4
@@ -365,25 +396,25 @@ class TextualRenderer(BaseRenderer):
if hint: if hint:
line.append(f" {hint}", style="dim cyan") line.append(f" {hint}", style="dim cyan")
self._buffer.append(line) self._add_line(line)
self._buffer.append(Text("")) # spacing self._add_line(Text("")) # spacing
def draw_filter_list(self, items, filter_text, selected_index, def draw_filter_list(self, items, filter_text, selected_index,
title=''): title=''):
h, w = self.get_size() h, w = self.get_size()
if title: if title:
self._buffer.append(Text(f" {title}", style="bold white")) self._add_line(Text(f" {title}", style="bold white"))
self._buffer.append(Text(" " + "─" * (w - 4), style="blue")) self._add_line(Text(" " + "─" * (w - 4), style="blue"))
filter_line = Text() filter_line = Text()
filter_line.append(" Filtro: ", style="cyan") filter_line.append(" Filtro: ", style="cyan")
filter_line.append(filter_text + "_", filter_line.append(filter_text + "_",
style="bold white on rgb(0,100,140)") style="bold white on rgb(0,100,140)")
self._buffer.append(filter_line) self._add_line(filter_line)
self._buffer.append(Text(" " + "─" * (w - 4), style="blue")) self._add_line(Text(" " + "─" * (w - 4), style="blue"))
visible = h - 10 visible = h - 10
if visible < 1: if visible < 1:
@@ -403,17 +434,17 @@ class TextualRenderer(BaseRenderer):
marker = "\u25b8 " if idx == selected_index else " " marker = "\u25b8 " if idx == selected_index else " "
if idx == selected_index: if idx == selected_index:
entry = pad_right(f"{marker}{num}. {label}", w - 4) entry = pad_right(f"{marker}{num}. {label}", w - 4)
self._buffer.append( self._add_line(
Text(f" {entry}", Text(f" {entry}",
style="bold white on rgb(30,60,120)") style="bold white on rgb(30,60,120)")
) )
else: else:
self._buffer.append( self._add_line(
Text(f" {marker}{num}. {label}", style="white") Text(f" {marker}{num}. {label}", style="white")
) )
drawn += 1 drawn += 1
self._buffer.append(Text( self._add_line(Text(
f" {len(items)} elementos", style="dim cyan" f" {len(items)} elementos", style="dim cyan"
)) ))
@@ -421,9 +452,9 @@ class TextualRenderer(BaseRenderer):
h, w = self.get_size() h, w = self.get_size()
if title: if title:
self._buffer.append(Text(f" {title}", style="bold white")) self._add_line(Text(f" {title}", style="bold white"))
self._buffer.append(Text(" " + "─" * (w - 4), style="blue")) self._add_line(Text(" " + "─" * (w - 4), style="blue"))
self._buffer.append(Text("")) self._add_line(Text(""))
n_cols = len(columns) n_cols = len(columns)
if n_cols == 0: if n_cols == 0:
@@ -444,12 +475,13 @@ class TextualRenderer(BaseRenderer):
no_wrap=True) no_wrap=True)
if not columns[0].get("rows"): if not columns[0].get("rows"):
self._buffer.append(table) self._add_lines(table, 2)
return return
n_rows = len(columns[0]["rows"]) n_rows = len(columns[0]["rows"])
max_rows = h - 8 max_rows = h - 8
for i in range(min(n_rows, max_rows)): actual = min(n_rows, max_rows)
for i in range(actual):
lbl = (columns[0]["rows"][i][0] lbl = (columns[0]["rows"][i][0]
if i < len(columns[0]["rows"]) else "") if i < len(columns[0]["rows"]) else "")
vals = [] vals = []
@@ -459,10 +491,18 @@ class TextualRenderer(BaseRenderer):
vals.append(str(val)) vals.append(str(val))
table.add_row(lbl, *vals) table.add_row(lbl, *vals)
self._buffer.append(table) self._add_lines(table, actual + 2)
# ── Low-level drawing ──────────────────────────────────────────── # ── Low-level drawing ────────────────────────────────────────────
def _render_styled(self, text, style="white"):
"""Render styled text to a string via Rich."""
sio = StringIO()
c = Console(file=sio, width=self._width, highlight=False,
force_terminal=True, color_system="truecolor")
c.print(Text(text, style=style), end="")
return sio.getvalue()
def draw_text(self, row, col, text, style='normal'): def draw_text(self, row, col, text, style='normal'):
style_map = { style_map = {
"normal": "white", "header": "bold cyan", "normal": "white", "header": "bold cyan",
@@ -473,14 +513,9 @@ class TextualRenderer(BaseRenderer):
"field_label": "cyan", "field_value": "bold white", "field_label": "cyan", "field_value": "bold white",
"field_active": "bold white on rgb(0,100,140)", "field_active": "bold white on rgb(0,100,140)",
} }
# For positioned text, write directly (used by dialogs)
rich_style = style_map.get(style, "white") rich_style = style_map.get(style, "white")
sys.stdout.write(f"\033[{row + 1};{col + 1}H") rendered = self._render_styled(text, rich_style)
sio = StringIO() sys.stdout.write(f"\033[{row + 1};{col + 1}H{rendered}")
c = Console(file=sio, width=self._width, highlight=False,
force_terminal=True, color_system="truecolor")
c.print(Text(text, style=rich_style), end="")
sys.stdout.write(sio.getvalue())
sys.stdout.flush() sys.stdout.flush()
def draw_box(self, top, left, height, width, title=''): def draw_box(self, top, left, height, width, title=''):
@@ -494,29 +529,25 @@ class TextualRenderer(BaseRenderer):
if height < 2 or width < 2: if height < 2 or width < 2:
return return
style = "blue"
if title: if title:
t = truncate(title, width - 4) t = truncate(title, width - 4)
top_line = BOX_TL + BOX_H + t + BOX_H * (width - 3 - len(t)) + BOX_TR top_line = BOX_TL + BOX_H + t + BOX_H * (width - 3 - len(t)) + BOX_TR
else: else:
top_line = BOX_TL + BOX_H * (width - 2) + BOX_TR top_line = BOX_TL + BOX_H * (width - 2) + BOX_TR
self._write_at(top, left, top_line, style) self._write_at(top, left, top_line, "blue")
for r in range(1, height - 1): for r in range(1, height - 1):
self._write_at(top + r, left, BOX_V + " " * (width - 2) + BOX_V, self._write_at(top + r, left,
style) BOX_V + " " * (width - 2) + BOX_V, "blue")
bottom_line = BOX_BL + BOX_H * (width - 2) + BOX_BR bottom_line = BOX_BL + BOX_H * (width - 2) + BOX_BR
self._write_at(top + height - 1, left, bottom_line, style) self._write_at(top + height - 1, left, bottom_line, "blue")
def _write_at(self, row, col, text, style="white"): def _write_at(self, row, col, text, style="white"):
"""Write styled text at absolute screen position.""" """Write styled text at absolute screen position."""
sio = StringIO() rendered = self._render_styled(text, style)
c = Console(file=sio, width=self._width, highlight=False, sys.stdout.write(f"\033[{row + 1};{col + 1}H{rendered}")
force_terminal=True, color_system="truecolor")
c.print(Text(text, style=style), end="")
sys.stdout.write(f"\033[{row + 1};{col + 1}H{sio.getvalue()}")
# ── Dialogs ────────────────────────────────────────────────────── # ── Dialogs ──────────────────────────────────────────────────────
@@ -568,7 +599,6 @@ class TextualRenderer(BaseRenderer):
left = max((w - box_w) // 2, 0) left = max((w - box_w) // 2, 0)
buf = [] buf = []
# Show cursor during input
sys.stdout.write("\033[?25h") sys.stdout.write("\033[?25h")
sys.stdout.flush() sys.stdout.flush()
@@ -602,11 +632,3 @@ class TextualRenderer(BaseRenderer):
elif 32 <= key <= 126: elif 32 <= key <= 126:
if len(buf) < max_len: if len(buf) < max_len:
buf.append(chr(key)) buf.append(chr(key))
# ── Module-level helpers ─────────────────────────────────────────────
def _has_data(fd, timeout=0.02):
"""Return True if there is data waiting on file descriptor *fd*."""
r, _, _ = select.select([fd], [], [], timeout)
return bool(r)