cleanup for review

src/cascadia/TerminalCore/Terminal.cpp

@@ -1586,6 +1586,7 @@
 
 void Terminal::PreviewText(std::wstring_view input)
 {
+ // Our suggestion text is default-on-default, in italics.
  static constexpr TextAttribute previewAttrs{ CharacterAttributes::Italics, TextColor{}, TextColor{}, 0u, TextColor{} };
 
  auto lock = LockForWriting();
@@ -1597,44 +1598,37 @@
  return;
  }
 
- // HACK trim off leading DEL chars.
+ // When we're previewing suggestions, they might be preceeded with DEL
+ // characters to backspace off the old command.
+ //
+ // But also, in the case of something like pwsh, there might be MORE "ghost"
+ // text in the buffer _after_ the commandline.
+ //
+ // We need to trim off the leading DELs, then pad out the rest of the line
+ // to cover any other ghost text.
  std::wstring_view view{ input };
+ // Where do the DELs end?
  const auto strBegin = view.find_first_not_of(L"\x7f");
-
- // // What we actually want to display is the text that would remain after
- // // accounting for the leading backspaces. So trim off the leading
- // // backspaces, AND and equal number of "real" characters.
- // if (strBegin != std::wstring::npos)
- // {
- // view = view.substr(strBegin * 2);
- // }
-
- // snippetPreview.text = view;
- // // // Hack, part the second: Pad the remaining text with spaces.
- // // const auto originalLen = input.size();
- // // const auto unpaddedLen = snippetPreview.text.size();
- // // if (unpaddedLen < originalLen)
- // // {
- // // snippetPreview.text.insert(snippetPreview.text.size(), originalLen + unpaddedLen, L' ');
- // // }
+ if (strBegin != std::wstring::npos)
  {
- // Attempt 2
- const auto bufferWidth = _GetMutableViewport().Width();
-  const auto cursorX = _activeBuffer().GetCursor().GetPosition().x;
-  const auto expectedLenTillEnd = strBegin + (bufferWidth - cursorX);
-  if (strBegin != std::wstring::npos)
-  {
-  view = view.substr(strBegin);
-  }
-  snippetPreview.text = view;
-  const auto originalSize{ snippetPreview.text.size() };
-  if (expectedLenTillEnd > originalSize)
-  {
-  snippetPreview.text.insert(originalSize, expectedLenTillEnd - originalSize, L' ');
- }
+ // Trim them off.
+ view = view.substr(strBegin);
+ }
+ // How many spaces do we need, so that the preview exactly covers the entire
+ // prompt, all the way to the end of the viewport?
+ const auto bufferWidth = _GetMutableViewport().Width();
+ const auto cursorX = _activeBuffer().GetCursor().GetPosition().x;
+ const auto expectedLenTillEnd = strBegin + (bufferWidth - cursorX);
+ std::wstring preview{ view };
+ const auto originalSize{ preview.size() };
+ if (expectedLenTillEnd > originalSize)
+ {
+ // pad it out
+ preview.insert(originalSize, expectedLenTillEnd - originalSize, L' ');
  }
+ snippetPreview.text = til::visualize_nonspace_control_codes(preview);
+ // Build our composition data
  const auto len = snippetPreview.text.size();
- // snippetPreview.attributes[0] = Microsoft::Console::Render::CompositionRange{ len, TextAttribute{} };
  snippetPreview.attributes.clear();
  snippetPreview.attributes.emplace_back(len, previewAttrs);
  snippetPreview.cursorPos = len;