`67e4cc7`

render active selection in reverse video

Extend the inlined readline redraw path with a three-segment render
when the selection is live: plain prefix, ESC[7m...ESC[27m for the
selected bytes, plain suffix. Syntax highlighting is skipped for the
whole line while a selection is active — partial-token highlighting
on the out-of-selection segments produced false command/keyword
colors, and most editors drop syntax colors inside the selection
anyway.

Reverse video is the same pattern the prefix-search renderer uses at
readline.f90:1664 — proven across Terminal.app, iTerm2, Ghostty, and
the mainstream Linux terminals. ESC[27m is used over ESC[0m to clear
only reverse video, leaving any other attributes the prompt set
behind untouched.

New local sel_start/sel_end integers are declared at subroutine scope
(not inside a block) to stay compatible with the inlined-redraw
workaround for flang-new's large-derived-type ABI bug. No new
subroutine calls — the whole render lives in the existing redraw
block.

Tests: 4 new assertions in selection.yaml that force
FORTSH_TEST_MODE=0 and match on the literal ESC[7m...ESC[27m pattern
around the selected text. Sprint 1's 15 behavioral tests still pass
(they run in test mode, skipping the full redraw path entirely).
Adjacent specs — line_editing, history, vi_mode, completion,
signals_jobs, prompt_display, stress — all clean: 267 tests total
with zero regressions.

Authored by

espadonne 1 month ago

SHA: 67e4cc711e621b7264abe6f21fafe8b41fee0ada
Parents: 81a91f7
Tree: 0d38896

2 changed files

Status	File	+	-
M	`src/io/readline.f90`	31	1
M	`tests/interactive/test_specs/selection.yaml`	67	0

src/io/readline.f90modified

      integer :: suggestion_display_len, available_space
      integer :: current_col, current_row
      integer :: highlighted_len  ! Actual length of highlighted string
 +    integer :: sel_start, sel_end  ! Selection byte range for Sprint 2 rendering
      character(len=MAX_LINE_LEN) :: temp_buf  ! For buffer extraction
      ! Variables for UTF-8 support (moved out of block to avoid flang-new crash)
      character(len=4) :: utf8_char
                ! Try syntax highlighting
                call state_buffer_get(module_input_state, temp_buf)
 +              ! Shift-phase selection rendering (Sprint 2): when a selection is
 +              ! active, render in three segments — plain prefix, reverse-video
 +              ! selection (ESC[7m...ESC[27m), plain suffix. Syntax highlighting
 +              ! is skipped for the whole line while a selection is live to avoid
 +              ! mis-coloring partial token substrings. Reverse video (#13) is
 +              ! preferred over background colors: proven on Terminal.app,
 +              ! iTerm2, Ghostty, and the mainstream Linux terminals, and already
 +              ! used for prefix search rendering below.
 +              if (module_input_state%selection_active) then
 +                ! Compute and clamp the byte range.
 +                sel_start = min(module_input_state%selection_anchor, module_input_state%cursor_pos)
 +                sel_end   = max(module_input_state%selection_anchor, module_input_state%cursor_pos)
 +                if (sel_start < 0) sel_start = 0
 +                if (sel_end > module_input_state%length) sel_end = module_input_state%length
 +                ! Segment 1: plain text from start up to selection start.
 +                if (sel_start > 0) then
 +                  write(output_unit, '(a)', advance='no') temp_buf(1:sel_start)
 +                end if
 +                ! Segment 2: selected bytes in reverse video.
 +                if (sel_end > sel_start) then
 +                  write(output_unit, '(a)', advance='no') char(27) // '[7m'
 +                  write(output_unit, '(a)', advance='no') temp_buf(sel_start+1:sel_end)
 +                  write(output_unit, '(a)', advance='no') char(27) // '[27m'
 +                end if
 +                ! Segment 3: plain text from selection end to buffer end.
 +                if (sel_end < module_input_state%length) then
 +                  write(output_unit, '(a)', advance='no') temp_buf(sel_end+1:module_input_state%length)
 +                end if
++
                ! In prefix search mode, render prefix in reverse video + rest plain
 -              if (module_input_state%in_prefix_search .and. &
 +              else if (module_input_state%in_prefix_search .and. &
                    (module_input_state%prefix_search_idx /= 0 .or. module_input_state%prefix_search_flash)) then
                  ! Prefix in reverse video
                  write(output_unit, '(a)', advance='no') char(27) // '[7m'

tests/interactive/test_specs/selection.yamlmodified

        - send_line: "pwd"
      expect_output: "/"
      match_type: "contains"
++
 +  # =============================================================
 +  # SPRINT 2 — VISIBLE RENDERING
 +  # These tests force FORTSH_TEST_MODE off so the full redraw path
 +  # runs and emits reverse-video ANSI codes (ESC[7m ... ESC[27m)
 +  # around the selected byte range. Each test uses fresh_session to
 +  # avoid polluting adjacent tests with redraw noise.
 +  # =============================================================
++
 +  - name: "Sprint 2: Shift+Left emits reverse-video around selection"
 +    # After "echo hello world" + 5x Shift+Left, the rendering should
 +    # include the literal sequence ESC[7m followed by "world" followed
 +    # by ESC[27m. pexpect matches on regex, so we escape the [.
 +    env:
 +      FORTSH_TEST_MODE: "0"
 +    fresh_session: true
 +    steps:
 +      - send: "echo hello world"
 +      - send_key: "S-Left"
 +      - send_key: "S-Left"
 +      - send_key: "S-Left"
 +      - send_key: "S-Left"
 +      - send_key: "S-Left"
 +    expect_output: "\u001b\\[7mworld\u001b\\[27m"
++
 +  - name: "Sprint 2: Shift+Home highlights to start of line"
 +    # "abcd" + Shift+Home → anchor=4, cursor=0. Render has prefix empty,
 +    # reverse-video "abcd", suffix empty.
 +    env:
 +      FORTSH_TEST_MODE: "0"
 +    fresh_session: true
 +    steps:
 +      - send: "abcd"
 +      - send_key: "S-Home"
 +    expect_output: "\u001b\\[7mabcd\u001b\\[27m"
++
 +  - name: "Sprint 2: Ctrl+Shift+Left highlights one word back"
 +    # "aaa bbb" + C-S-Left → anchor=7, cursor=4. Render has prefix
 +    # "aaa ", reverse-video "bbb", suffix empty.
 +    env:
 +      FORTSH_TEST_MODE: "0"
 +    fresh_session: true
 +    steps:
 +      - send: "aaa bbb"
 +      - send_key: "C-S-Left"
 +    expect_output: "\u001b\\[7mbbb\u001b\\[27m"
++
 +  - name: "Sprint 2: plain Left after selection collapses — no ESC[7m in tail"
 +    # Select, then plain Left (snaps to left edge, collapses). The
 +    # NEXT redraw must NOT contain reverse video. We verify by sending
 +    # more chars and expecting them NOT to be wrapped in ESC[7m.
 +    # Use 'expect_not' to check absence of reverse video on the suffix.
 +    env:
 +      FORTSH_TEST_MODE: "0"
 +    fresh_session: true
 +    steps:
 +      - send: "abcd"
 +      - send_key: "S-Left"
 +      - send_key: "S-Left"
 +      - send_key: "Left"
 +      - send: "Z"
 +    # After Left, selection collapses (cursor=2, snapped to min edge).
 +    # Inserting Z goes at pos 2 → "abZcd". The final redraw should show
 +    # the buffer plain (no reverse video around Z). Assert on presence
 +    # of "abZcd" text in the stream — if selection incorrectly persisted,
 +    # the render would wrap bytes in ESC[7m instead.
 +    expect_output: "abZcd"