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Merged
waf merged 1 commit into from
May 31, 2026
Merged

Add some emacs/readline keybindings #288

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4 changes: 2 additions & 2 deletions src/PrettyPrompt/KeyBindings.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -34,8 +34,8 @@ public KeyBindings(
TriggerCompletionList = Get(triggerCompletionList, new KeyPressPattern(Control, Spacebar));
NewLine = Get(newLine, new KeyPressPattern(Shift, Enter), new KeyPressPattern(Alt, Enter));
SubmitPrompt = Get(submitPrompt, new(Enter), new(Control, Enter), new(Control | Alt, Enter));
HistoryPrevious = Get(historyPrevious, new KeyPressPattern(UpArrow));
HistoryNext = Get(historyNext, new KeyPressPattern(DownArrow));
HistoryPrevious = Get(historyPrevious, new KeyPressPattern(UpArrow), new KeyPressPattern(Control, P)); // Ctrl+P is the emacs binding
HistoryNext = Get(historyNext, new KeyPressPattern(DownArrow), new KeyPressPattern(Control, N)); // Ctrl+N is the emacs binding
TriggerOverloadList = triggerOverloadList;

static KeyPressPatterns Get(KeyPressPatterns patterns, params KeyPressPattern[] defaultPatterns)
Expand Down
118 changes: 70 additions & 48 deletions src/PrettyPrompt/Panes/CodePane.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -201,48 +201,52 @@ public async Task OnKeyDown(KeyPress key, CancellationToken cancellationToken)
case (Control, End) or (Control | Shift, End):
Document.Caret = Document.Length;
break;
case (Shift, LeftArrow):
case LeftArrow:
case (Shift, LeftArrow) or LeftArrow or (Control, B): // Ctrl+B = backward one char (emacs)
Document.Caret = Document.CalculateCaretIndexToLeft();
break;
case (Shift, RightArrow):
case RightArrow:
case (Shift, RightArrow) or RightArrow or (Control, F): // Ctrl+F = forward one char (emacs)
Document.Caret = Document.CalculateCaretIndexToRight();
break;
case (Control | Shift, LeftArrow):
case (Control, LeftArrow):
case (Control | Shift, LeftArrow) or (Control, LeftArrow) or (Alt, B): // Alt+b = backward one word (emacs)
Document.MoveToWordBoundary(-1);
break;
case (Control | Shift, RightArrow):
case (Control, RightArrow):
case (Control | Shift, RightArrow) or (Control, RightArrow) or (Alt, F): // Alt+f = forward one word (emacs)
Document.MoveToWordBoundary(+1);
break;
case (Control, Backspace) when selection is null:
var startDeleteIndex = Document.CalculateWordBoundaryIndexNearCaret(-1);
Document.Remove(this, startDeleteIndex, Document.Caret - startDeleteIndex);
break;
case (Control, Delete) when selection is null:
var endDeleteIndex = Document.CalculateWordBoundaryIndexNearCaret(+1);
Document.Remove(this, Document.Caret, endDeleteIndex - Document.Caret);
break;
case (Control, Backspace)
or (Control, H) // Ctrl+H = delete word backward, an alias of Ctrl+Backspace. Ideally this would be 'delete one character' but on Unix/macOS .NET reports the Ctrl+H byte (0x08) as (Control, Backspace). https://github.com/dotnet/runtime/issues/73379#issuecomment-1206168139
or (Alt, Backspace) // Alt+Backspace = delete word backward (emacs)
when selection is null:
{
var startDeleteIndex = Document.CalculateWordBoundaryIndexNearCaret(-1);
Document.Remove(this, startDeleteIndex, Document.Caret - startDeleteIndex);
break;
}
case (Control, Delete)
or (Alt, Delete) // Alt+Delete = delete word forward (Mac Option+forward-delete)
or (Alt, D) // Alt+d = delete word forward (emacs)
when selection is null:
{
var endDeleteIndex = Document.CalculateWordBoundaryIndexNearCaret(+1);
Document.Remove(this, Document.Caret, endDeleteIndex - Document.Caret);
break;
}
case Backspace when selection is null:
{
// delete the whole grapheme cluster to the left, not a single UTF-16 code unit
var clusterStart = Document.CalculateCaretIndexToLeft();
Document.Remove(this, clusterStart, Document.Caret - clusterStart);
break;
}
break;
case Delete when selection is null:
case (Delete or (Control, D)) when selection is null: // Ctrl+D = delete one char forwards (emacs)
{
// delete the whole grapheme cluster to the right, not a single UTF-16 code unit
var clusterEnd = Document.CalculateCaretIndexToRight();
Document.Remove(this, Document.Caret, clusterEnd - Document.Caret);
break;
}
break;
case (_, Delete) or (_, Backspace) or Delete or Backspace when selection.HasValue:
{
Document.DeleteSelectedText(this);
}
case (_, Delete) or (_, Backspace) or Delete or Backspace or (Control, D) or (Alt, D) or (Control, H) or (Control, K) or (Control, U) when selection.HasValue:
Document.DeleteSelectedText(this);
break;
case Tab or (Shift, Tab):
{
Expand Down Expand Up @@ -284,6 +288,20 @@ public async Task OnKeyDown(KeyPress key, CancellationToken cancellationToken)
await clipboard.SetTextAsync(Document.GetText(span).ToString(), cancellationToken).ConfigureAwait(false);
}

Document.Remove(this, span);
break;
}
case (Control, K) when selection is null: // Ctrl+K = delete from caret to end of the current line (emacs/readline kill-line); deletes only, does not write the clipboard
{
var lineEnd = Document.CalculateLineBoundaryIndexNearCaret(+1, smartHome: false);
var span = TextSpan.FromBounds(Document.Caret, lineEnd);
Document.Remove(this, span);
break;
}
case (Control, U) when selection is null: // Ctrl+U = delete from start of the current line to caret (readline/bash unix-line-discard; in emacs Ctrl+U is universal-argument); deletes only, does not write the clipboard
{
var lineStart = Document.CalculateLineBoundaryIndexNearCaret(-1, smartHome: false);
var span = TextSpan.FromBounds(lineStart, Document.Caret);
Document.Remove(this, span);
break;
}
Expand All @@ -299,36 +317,42 @@ public async Task OnKeyDown(KeyPress key, CancellationToken cancellationToken)
case (Shift, Insert) when key.PastedText is not null:
PasteText(key.PastedText);
break;
case (Control, V):
case (Control | Shift, V):
case (Shift, Insert):
var clipboardText = await clipboard.GetTextAsync(cancellationToken).ConfigureAwait(false);
PasteText(clipboardText);
break;
case (Control, V) or (Control | Shift, V) or (Shift, Insert):
{
var clipboardText = await clipboard.GetTextAsync(cancellationToken).ConfigureAwait(false);
PasteText(clipboardText);
break;
}
case (Control, Z):
Document.Undo(out var newSelection);
Selection = newSelection;
if (newSelection.HasValue)
{
completionPane.IsOpen = false;
overloadPane.IsOpen = false;
Document.Undo(out var undoSelection);
Selection = undoSelection;
if (undoSelection.HasValue)
{
completionPane.IsOpen = false;
overloadPane.IsOpen = false;
}
break;
}
break;
case (Control, Y):
Document.Redo(out newSelection);
Selection = newSelection;
if (newSelection.HasValue)
{
completionPane.IsOpen = false;
overloadPane.IsOpen = false;
Document.Redo(out var redoSelection);
Selection = redoSelection;
if (redoSelection.HasValue)
{
completionPane.IsOpen = false;
overloadPane.IsOpen = false;
}
break;
}
break;
default:
if (!(char.IsControl(key.ConsoleKeyInfo.KeyChar) || promptCallbacks.TryGetKeyPressCallbacks(key.ConsoleKeyInfo, out _)))
{
Document.InsertAtCaret(this, key.ConsoleKeyInfo.KeyChar);
if (!(char.IsControl(key.ConsoleKeyInfo.KeyChar) || promptCallbacks.TryGetKeyPressCallbacks(key.ConsoleKeyInfo, out _)))
{
Document.InsertAtCaret(this, key.ConsoleKeyInfo.KeyChar);
}
break;
}
break;
}
}

Expand Down Expand Up @@ -449,8 +473,7 @@ public async Task OnKeyUp(KeyPress key, CancellationToken cancellationToken)

switch (key.ObjectPattern)
{
case (Shift, UpArrow) when Cursor.Row > 0:
case UpArrow when Cursor.Row > 0:
case (Shift, UpArrow) or UpArrow or (Control, P) when Cursor.Row > 0: // Ctrl+P = previous line (emacs)
{
var newCursor = Cursor.MoveUp();
var aboveLine = WordWrappedLines[newCursor.Row];
Expand All @@ -459,8 +482,7 @@ public async Task OnKeyUp(KeyPress key, CancellationToken cancellationToken)
key.Handled = true;
break;
}
case (Shift, DownArrow) when Cursor.Row < WordWrappedLines.Count - 1:
case DownArrow when Cursor.Row < WordWrappedLines.Count - 1:
case (Shift, DownArrow) or DownArrow or (Control, N) when Cursor.Row < WordWrappedLines.Count - 1: // Ctrl+N = next line (emacs)
{
var newCursor = Cursor.MoveDown();
var belowLine = WordWrappedLines[newCursor.Row];
Expand Down
41 changes: 24 additions & 17 deletions src/PrettyPrompt/Panes/CompletionPane.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -96,28 +96,35 @@ async Task IKeyPressHandler.OnKeyDown(KeyPress key, CancellationToken cancellati

switch (key.ObjectPattern)
{
case Home or (_, Home):
case End or (_, End):
case (Shift, LeftArrow or RightArrow or UpArrow or DownArrow or Home or End) or
case Home or (_, Home) or
End or (_, End) or
(Shift, LeftArrow or RightArrow or UpArrow or DownArrow or Home or End) or
(Control | Shift, LeftArrow or RightArrow or UpArrow or DownArrow or Home or End) or
(Control, A):
await Close(cancellationToken).ConfigureAwait(false);
return;
case LeftArrow or RightArrow:
// mirror the document's grapheme-cluster-aware caret movement (see CodePane arrow handling)
int caretNew = key.ConsoleKeyInfo.Key == LeftArrow
? codePane.Document.CalculateCaretIndexToLeft()
: codePane.Document.CalculateCaretIndexToRight();
if (caretNew < spanToReplace.Start || caretNew > spanToReplace.Start + spanToReplace.Length)
{
await Close(cancellationToken).ConfigureAwait(false);
return;
}
break;
case LeftArrow or RightArrow or (Control, B) or (Control, F): // Ctrl+B/Ctrl+F are emacs char movement
{
// mirror the document's grapheme-cluster-aware caret movement (see CodePane arrow handling)
bool movingLeft = key.ObjectPattern is LeftArrow or (Control, B);
int caretNew = movingLeft
? codePane.Document.CalculateCaretIndexToLeft()
: codePane.Document.CalculateCaretIndexToRight();
if (caretNew < spanToReplace.Start || caretNew > spanToReplace.Start + spanToReplace.Length)
{
await Close(cancellationToken).ConfigureAwait(false);
return;
}
break;
}
case Escape:
await Close(cancellationToken).ConfigureAwait(false);
key.Handled = true;
return;
{
await Close(cancellationToken).ConfigureAwait(false);
key.Handled = true;
return;
}
default:
break;
}
Expand Down Expand Up @@ -150,11 +157,11 @@ async Task IKeyPressHandler.OnKeyDown(KeyPress key, CancellationToken cancellati
//completion list is open and there are some items
switch (key.ObjectPattern)
{
case DownArrow:
case DownArrow or (Control, N): // Ctrl+N = next item (emacs)
await FilteredView.IncrementSelectedIndex(cancellationToken).ConfigureAwait(false);
key.Handled = true;
break;
case UpArrow:
case UpArrow or (Control, P): // Ctrl+P = previous item (emacs)
await FilteredView.DecrementSelectedIndex(cancellationToken).ConfigureAwait(false);
key.Handled = true;
break;
Expand Down
8 changes: 4 additions & 4 deletions src/PrettyPrompt/Panes/OverloadPane.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -16,6 +16,7 @@
using PrettyPrompt.Highlighting;
using PrettyPrompt.Rendering;
using static System.ConsoleKey;
using static System.ConsoleModifiers;

namespace PrettyPrompt.Panes;

Expand Down Expand Up @@ -194,8 +195,7 @@ Task IKeyPressHandler.OnKeyDown(KeyPress key, CancellationToken cancellationToke
case Escape:
Close();
break;
case DownArrow:
case UpArrow:
case DownArrow or UpArrow or (Control, N) or (Control, P): // Ctrl+N/Ctrl+P are emacs aliases
patternToProcessInKeyUp = key.ObjectPattern;
key.Handled = true;
break;
Expand Down Expand Up @@ -225,11 +225,11 @@ async Task IKeyPressHandler.OnKeyUp(KeyPress key, CancellationToken cancellation
{
switch (key.ObjectPattern)
{
case DownArrow:
case DownArrow or (Control, N): // Ctrl+N = next overload (emacs)
++SelectedItemIndex;
key.Handled = true;
break;
case UpArrow:
case UpArrow or (Control, P): // Ctrl+P = previous overload (emacs)
--SelectedItemIndex;
key.Handled = true;
break;
Expand Down
16 changes: 16 additions & 0 deletions tests/PrettyPrompt.Tests/CompletionTests.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -47,6 +47,22 @@ public async Task ReadLine_MultipleCompletion()
Assert.Equal("Aardvark Zebra Alligator", result.Text);
}

[Fact]
public async Task ReadLine_MultipleCompletion_NavigatesMenuWithCtrlNAndCtrlP()
{
var console = ConsoleStub.NewConsole();
// identical to ReadLine_MultipleCompletion, but navigate the open menu with Ctrl+N / Ctrl+P
// (emacs aliases for the arrow keys) instead of Down/Up.
console.StubInput($"Aa{Enter} Z{Tab} Alli{Backspace}{Backspace}{Control}{N}{Control}{P}{Control}{N}{Enter}{Enter}");

var prompt = ConfigurePrompt(console);

var result = await prompt.ReadLineAsync();

Assert.True(result.IsSuccess);
Assert.Equal("Aardvark Zebra Alligator", result.Text);
}

[Fact]
public async Task ReadLine_MultilineCompletion()
{
Expand Down
22 changes: 22 additions & 0 deletions tests/PrettyPrompt.Tests/HistoryTests.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -59,6 +59,28 @@ public async Task ReadLine_WithHistory_CyclesThroughHistory()
Assert.Equal("", result.Text);
}

[Fact]
public async Task ReadLine_WithHistory_CyclesWithCtrlPAndCtrlN()
{
// Ctrl+P / Ctrl+N are emacs aliases for the Up/Down history bindings
var console = ConsoleStub.NewConsole();
var prompt = new Prompt(console: console);

console.StubInput($"Hello World{Enter}");
await prompt.ReadLineAsync();

console.StubInput($"Howdy World{Enter}");
await prompt.ReadLineAsync();

console.StubInput($"How ya' doin world{Enter}");
await prompt.ReadLineAsync();

// Ctrl+P three times walks back to the oldest entry; Ctrl+N steps forward one.
console.StubInput($"{Control}{P}{Control}{P}{Control}{P}{Control}{N}{Enter}");
var result = await prompt.ReadLineAsync();
Assert.Equal("Howdy World", result.Text);
}

[Fact]
public async Task ReadLine_WithHistory_DoNotSaveEmptyInput()
{
Expand Down
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