wip

babi/buf.py

@@ -130,7 +130,7 @@ class Buf:
         return victim
 
     def restore_eof_invariant(self) -> None:
-        """the file lines will always contain a blank empty string at the end'
+        """the file lines will always contain a blank empty string at the end
         to simplify rendering.  call this whenever the last line may change
         """
         if self[-1] != '':
@@ -237,8 +237,10 @@ class Buf:
     # rendered lines
 
     def rendered_line(self, idx: int, margin: Margin) -> str:
-        x = self._cursor_x if idx == self.y else 0
-        return scrolled_line(self._lines[idx].expandtabs(4), x, margin.cols)
+        line = self._lines[idx]
+        positions = self.line_positions(idx)
+        cursor_x = self._cursor_x if idx == self.y else 0
+        return scrolled_line(line, positions, cursor_x, margin.cols)
 
     # movement
 
@@ -273,7 +275,7 @@ class Buf:
         if self.x >= len(self._lines[self.y]):
             if self.y < len(self._lines) - 1:
                 self.down(margin)
-                self.x = 0
+                self.home()
         else:
             self.x += 1
 
@@ -281,10 +283,16 @@ class Buf:
         if self.x == 0:
             if self.y > 0:
                 self.up(margin)
-                self.x = len(self._lines[self.y])
+                self.end()
         else:
             self.x -= 1
 
+    def home(self) -> None:
+        self.x = 0
+
+    def end(self) -> None:
+        self.x = len(self._lines[self.y])
+
     # screen movement
 
     def file_up(self, margin: Margin) -> None:
@@ -298,3 +306,9 @@ class Buf:
             self.file_y += 1
             if self.y < self.file_y:
                 self.down(margin)
+
+    # key input
+
+    def c(self, s: str) -> None:
+        self[self.y] = self[self.y][:self.x] + s + self[self.y][self.x:]
+        self.x += len(s)

babi/file.py

@@ -280,11 +280,11 @@ class File:
 
     @action
     def home(self, margin: Margin) -> None:
-        self.buf.x = 0
+        self.buf.home()
 
     @action
     def end(self, margin: Margin) -> None:
-        self.buf.x = len(self.buf[self.buf.y])
+        self.buf.end()
 
     @action
     def ctrl_up(self, margin: Margin) -> None:
@@ -698,10 +698,8 @@ class File:
 
     @edit_action('text', final=False)
     @clear_selection
-    def c(self, wch: str, margin: Margin) -> None:
-        s = self.buf[self.buf.y]
-        self.buf[self.buf.y] = s[:self.buf.x] + wch + s[self.buf.x:]
-        self.buf.x += len(wch)
+    def c(self, wch: str) -> None:
+        self.buf.c(wch)
         self.buf.restore_eof_invariant()
 
     def finalize_previous_action(self) -> None:

babi/horizontal_scrolling.py

@@ -1,4 +1,6 @@
+import bisect
 import curses
+from typing import Tuple
 
 from babi.cached_property import cached_property
 
@@ -18,18 +20,37 @@ def line_x(x: int, width: int) -> int:
         )
 
 
-def scrolled_line(s: str, x: int, width: int) -> str:
-    l_x = line_x(x, width)
+def scrolled_line(
+        s: str,
+        positions: Tuple[int, ...],
+        cursor_x: int,
+        width: int,
+) -> str:
+    l_x = line_x(cursor_x, width)
     if l_x:
-        s = f'«{s[l_x + 1:]}'
-        if len(s) > width:
-            return f'{s[:width - 1]}»'
+        l_x_min = l_x + 1
+        start = bisect.bisect_left(positions, l_x_min)
+        pad_left = '«' * (positions[start] - l_x)
+
+        l_x_max = l_x + width
+        if positions[-1] > l_x_max:
+            end_max = l_x_max - 1
+            end = bisect.bisect_left(positions, end_max)
+            if positions[end] > end_max:
+                end -= 1
+            pad_right = '»' * (l_x_max - positions[end])
+            return f'{pad_left}{s[start:end].expandtabs(4)}{pad_right}'
         else:
-            return s.ljust(width)
-    elif len(s) > width:
-        return f'{s[:width - 1]}»'
+            return f'{pad_left}{s[start:]}'.ljust(width)
+    elif positions[-1] > width:
+        end_max = width - 1
+        end = bisect.bisect_left(positions, end_max)
+        if positions[end] > end_max:
+            end -= 1
+        pad_right = '»' * (width - positions[end])
+        return f'{s[:end].expandtabs(4)}{pad_right}'
     else:
-        return s.ljust(width)
+        return s.expandtabs(4).ljust(width)
 
 
 class _CalcWidth:

babi/main.py

@@ -33,7 +33,7 @@ def _edit(screen: Screen, stdin: str) -> EditResult:
                 return ret
         elif key.keyname == b'STRING':
             assert isinstance(key.wch, str), key.wch
-            screen.file.c(key.wch, screen.margin)
+            screen.file.c(key.wch)
         else:
             screen.status.update(f'unknown key: {key}')
 

babi/prompt.py

@@ -6,8 +6,7 @@ from typing import Tuple
 from typing import TYPE_CHECKING
 from typing import Union
 
-from babi.horizontal_scrolling import line_x
-from babi.horizontal_scrolling import scrolled_line
+from babi.buf import Buf
 
 if TYPE_CHECKING:
     from babi.main import Screen  # XXX: circular
@@ -19,17 +18,25 @@ class Prompt:
     def __init__(self, screen: 'Screen', prompt: str, lst: List[str]) -> None:
         self._screen = screen
         self._prompt = prompt
-        self._lst = lst
-        self._y = len(lst) - 1
+        self._buf = Buf(lst)
+        self._buf.y = self._buf.file_y = len(lst) - 1
         self._x = len(self._s)
 
+    @property
+    def _x(self) -> int:
+        return self._buf.x
+
+    @_x.setter
+    def _x(self, x: int) -> None:
+        self._buf.x = x
+
     @property
     def _s(self) -> str:
-        return self._lst[self._y]
+        return self._buf[self._buf.y]
 
     @_s.setter
     def _s(self, s: str) -> None:
-        self._lst[self._y] = s
+        self._buf[self._buf.y] = s
 
     def _render_prompt(self, *, base: Optional[str] = None) -> None:
         base = base or self._prompt
@@ -39,24 +46,26 @@ class Prompt:
             prompt_s = f'{base[:self._screen.margin.cols - 7]}…: '
         else:
             prompt_s = f'{base}: '
+
         width = self._screen.margin.cols - len(prompt_s)
-        line = scrolled_line(self._s, self._x, width)
-        cmd = f'{prompt_s}{line}'
+        margin = self._screen.margin._replace(cols=width)
+        cmd = f'{prompt_s}{self._buf.rendered_line(self._buf.y, margin)}'
         prompt_line = self._screen.margin.lines - 1
         self._screen.stdscr.insstr(prompt_line, 0, cmd, curses.A_REVERSE)
-        x = len(prompt_s) + self._x - line_x(self._x, width)
-        self._screen.stdscr.move(prompt_line, x)
+
+        _, x_off = self._buf.cursor_position(margin)
+        self._screen.stdscr.move(prompt_line, len(prompt_s) + x_off)
 
     def _up(self) -> None:
-        self._y = max(0, self._y - 1)
-        self._x = len(self._s)
+        self._buf.up(self._screen.margin)
+        self._x = len(self._buf[self._buf.y])
 
     def _down(self) -> None:
-        self._y = min(len(self._lst) - 1, self._y + 1)
-        self._x = len(self._s)
+        self._buf.down(self._screen.margin)
+        self._x = len(self._buf[self._buf.y])
 
     def _right(self) -> None:
-        self._x = min(len(self._s), self._x + 1)
+        self._x = min(len(self._buf[self._buf.y]), self._x + 1)
 
     def _left(self) -> None:
         self._x = max(0, self._x - 1)
@@ -65,11 +74,11 @@ class Prompt:
         self._x = 0
 
     def _end(self) -> None:
-        self._x = len(self._s)
+        self._x = len(self._buf[self._buf.y])
 
     def _ctrl_left(self) -> None:
         if self._x <= 1:
-            self._x = 0
+            self._buf.home()
         else:
             self._x -= 1
             tp = self._s[self._x - 1].isalnum()
@@ -78,7 +87,7 @@ class Prompt:
 
     def _ctrl_right(self) -> None:
         if self._x >= len(self._s) - 1:
-            self._x = len(self._s)
+            self._buf.end()
         else:
             self._x += 1
             tp = self._s[self._x].isalnum()
@@ -103,9 +112,9 @@ class Prompt:
     def _check_failed(self, idx: int, s: str) -> Tuple[bool, int]:
         failed = False
         for search_idx in range(idx, -1, -1):
-            if s in self._lst[search_idx]:
-                idx = self._y = search_idx
-                self._x = self._lst[search_idx].index(s)
+            if s in self._buf[search_idx]:
+                idx = self._buf.y = search_idx
+                self._x = self._buf[search_idx].index(s)
                 break
         else:
             failed = True
@@ -113,7 +122,7 @@ class Prompt:
 
     def _reverse_search(self) -> Union[None, str, PromptResult]:
         reverse_s = ''
-        idx = self._y
+        idx = self._buf.y
         while True:
             fail, idx = self._check_failed(idx, reverse_s)
 
@@ -174,8 +183,7 @@ class Prompt:
     }
 
     def _c(self, c: str) -> None:
-        self._s = self._s[:self._x] + c + self._s[self._x:]
-        self._x += len(c)
+        self._buf.c(c)
 
     def run(self) -> Union[PromptResult, str]:
         while True:

requirements-dev.txt

@@ -3,3 +3,4 @@ coverage
 git+https://github.com/asottile/hecate@875567f
 pytest
 remote-pdb
+wcwidth

tests/features/conftest.py

@@ -9,6 +9,7 @@ from typing import Union
 from unittest import mock
 
 import pytest
+import wcwidth
 
 from babi._types import Protocol
 from babi.main import main
@@ -71,7 +72,7 @@ class Screen:
         self.attrs[y] = line_attr[:x] + new + line_attr[x + len(s):]
 
         self.y = y
-        self.x = x + len(s)
+        self.x = x + wcwidth.wcswidth(s)
 
     def insstr(self, y, x, s, attr):
         line = self.lines[y]

tests/features/movement_test.py

@@ -415,10 +415,18 @@ def test_sequence_handling(run_only_fake):
 
 def test_indentation_using_tabs(run, tmpdir):
     f = tmpdir.join('f')
-    f.write(f'123456789\n\t12\t{"x" * 20}\n')
+    f.write(
+        f'123456789\n'
+        f'\t12\t{"x" * 20}\n'
+        f'\tnot long\n',
+    )
 
     with run(str(f), width=20) as h, and_exit(h):
-        h.await_text('123456789\n    12  xxxxxxxxxxx»\n')
+        h.await_text(
+            '123456789\n'
+            '    12  xxxxxxxxxxx»\n'
+            '    not long\n',
+        )
 
         h.press('Down')
         h.await_cursor_position(x=0, y=2)
@@ -438,3 +446,43 @@ def test_indentation_using_tabs(run, tmpdir):
         h.await_cursor_position(x=4, y=2)
         h.press('Up')
         h.await_cursor_position(x=4, y=1)
+
+
+def test_movement_with_wide_characters(run, tmpdir):
+    f = tmpdir.join('f')
+    f.write(
+        f'{"🙃" * 20}\n'
+        f'a{"🙃" * 20}\n',
+    )
+
+    with run(str(f), width=20) as h, and_exit(h):
+        h.await_text(
+            '🙃🙃🙃🙃🙃🙃🙃🙃🙃»»\n'
+            'a🙃🙃🙃🙃🙃🙃🙃🙃🙃»\n',
+        )
+
+        for _ in range(10):
+            h.press('Right')
+        h.await_text(
+            '««🙃🙃🙃🙃🙃🙃🙃🙃»»\n'
+            'a🙃🙃🙃🙃🙃🙃🙃🙃🙃»\n',
+        )
+
+        for _ in range(6):
+            h.press('Right')
+        h.await_text(
+            '««🙃🙃🙃🙃🙃🙃🙃\n'
+            'a🙃🙃🙃🙃🙃🙃🙃🙃🙃»\n',
+        )
+
+        h.press('Down')
+        h.await_text(
+            '🙃🙃🙃🙃🙃🙃🙃🙃🙃»»\n'
+            '«🙃🙃🙃🙃🙃🙃🙃🙃\n',
+        )
+
+        h.press('Left')
+        h.await_text(
+            '🙃🙃🙃🙃🙃🙃🙃🙃🙃»»\n'
+            '«🙃🙃🙃🙃🙃🙃🙃🙃🙃»\n',
+        )