feat(tui2): improve transcript copy fidelity

[joshka-oai]

Title: feat(tui2): improve transcript copy fidelity

This PR improves transcript selection → clipboard output in TUI2 so copied text matches user intent rather than the current viewport layout.

Note

streaming output still bakes in newlines during the stream — see streaming_wrapping_design.md for more details on fixing this.

What changes for users

• Copy treats soft-wrapped prose as a single logical line (no hard newlines introduced purely due to wrapping).
• Copy preserves meaningful indentation for code/preformatted content and avoids “narrow terminal truncates the copied line”.
• Copy emits Markdown source markers (inline backticks + fenced code blocks) even when we render via styling.

Design notes (what’s different vs tui)

• codex-tui largely deals with terminal-native selection/copy and only needs HistoryCell::transcript_lines(...).
• codex-tui2 implements app-driven selection/copy that can span off-screen content and soft-wrap boundaries, so we need extra metadata to preserve intent across reflow/scroll.

Implementation overview

Joiner plumbing (soft-wrap fidelity)

• codex-rs/tui2/src/history_cell.rs
  • Introduces TranscriptLinesWithJoiners { lines, joiner_before } + HistoryCell::transcript_lines_with_joiners(...).
  • joiner_before[i] is Some(joiner) when line i is a soft-wrap continuation and copy should insert joiner instead of ; None indicates a hard break.
• codex-rs/tui2/src/wrapping.rs
  • Adds word_wrap_line_with_joiners / word_wrap_lines_with_joiners.
  • Simplified so word_wrap_line delegates to word_wrap_line_with_joiners (single source of truth).

Transcript rendering split

• codex-rs/tui2/src/transcript_render.rs
  • Centralizes “cells → flattened visual lines”, TranscriptLineMeta, spacer rows, and joiners.
  • Applies viewport wrapping to prose while leaving preformatted/code lines unwrapped to preserve indentation.
  • Moves ANSI-export rendering (render_lines_to_ansi) out of app.rs.

Clipboard reconstruction

• codex-rs/tui2/src/transcript_copy.rs
  • Reconstructs clipboard text from the wrapped visual lines + joiners.
  • Uses style-derived cues to decide inline code vs code runs:
    • inline code spans are wrapped in backticks
    • code/preformatted runs are fenced with triple backticks
  • Selection slicing is display-width aware (handles wide glyphs).
  • Includes explicit handling so selecting “to the right edge” on code lines copies the full logical line (not viewport-truncated).

Copy UX separation

• codex-rs/tui2/src/transcript_copy_ui.rs
  • Shortcut detection + key matching + on-screen “copy” pill rendering/hit testing.

ANSI emission consistency

• codex-rs/tui2/src/insert_history.rs
  • Documents and implements direct SGR fg/bg emission for ratatui::Color (including Rgb/Indexed) so ANSI output is deterministic across impl Write backends (used by render_lines_to_ansi and tests).

Markdown rendering style fix (code-in-blockquote)

• codex-rs/tui2/src/markdown_render.rs
  • Ensures code blocks keep code styling even under blockquote style so downstream copy cues remain stable.

Reviewer notes / maintenance hazards

• Code/preformatted detection currently uses “cyan line/span styling” as the cue. If transcript styling changes, update:
  • transcript_copy’s is_code_block_line / span_is_inline_code
  • transcript_render’s preformatted “don’t wrap” predicate
• lines and joiner_before must stay aligned; transcript_render is the source of truth for both.

Tests

• Added/updated unit tests for:
  • joiner behavior and invariants in wrapping
  • copy reconstruction (soft-wrap joins, Markdown markers, code fences/indentation, viewport-edge code copying)
  • wide glyph selection/slicing cases
• Ran: cargo test -p codex-tui2

[joshka-oai]

Left side is select + copy of text from codex on right.
Lines are correctly rendered with corerct markdown and wrapping