Type at the window with a real keyboard: the akgl_typing test

xdotool closes the gap that shipped the missing SDL_StartTextInput(). Every
other keyboard test synthesises SDL events, which covers the code downstream
of SDL and cannot cover the code upstream of it -- so the suite stayed green
while the real keyboard was dead.

akgl_typing starts the driver under a pty, waits for the window with xdotool
search --sync, gives it focus, and types a program containing a string literal
and a lower-case one, polling the mirrored stdout for what they print. Verified
by reverting both halves of the text-input fix and watching it fail with the
reported symptom: READY, and nothing after it.

Skips rather than fails without a display, xdotool, script(1) or a window
manager -- none of those means the answer is no. It steals keyboard focus for
about fifteen seconds; AKBASIC_SKIP_INTERACTIVE=1 skips it deliberately.

xdotool and script(1) are documented as optional test dependencies, alongside
what gcovr and python3 already bought.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

tests/akgl_typing.sh

@@ -0,0 +1,115 @@
+#!/bin/bash
+#
+# Type at the SDL window with a real keyboard, and check what comes out.
+#
+# This is the only test in the repository that exercises the path a person
+# actually uses: X11 delivers a key press to a focused window, SDL composes it,
+# libakgl rings it, the line editor echoes it, and the interpreter runs it. Every
+# other keyboard test synthesises SDL events, which is a fine way to test the
+# code downstream of SDL and no way at all to test the code upstream of it.
+#
+# **It exists because that gap shipped a bug.** The frontend never called
+# SDL_StartTextInput(), so SDL emitted no text-input events, every keystroke
+# arrived with an empty `text`, and the editor dropped the lot -- no echo, and
+# nothing on stdout either, because RUN could never be typed. The suite was
+# green throughout, because it pushed the text-input events itself.
+#
+# Skips rather than fails when it cannot run: no display, no xdotool, no
+# script(1), no window, or no focus are all "this machine cannot answer the
+# question", not "the answer is no". CTest is told exit 77 means skipped.
+#
+# **It steals keyboard focus for a few seconds.** That is inherent -- the point
+# is a focused window. Set AKBASIC_SKIP_INTERACTIVE=1 to skip it while you work.
+
+set -u
+
+SKIP=77
+BASIC="${1:?usage: akgl_typing.sh <path to basic>}"
+WORK="$(mktemp -d)"
+trap 'rm -rf "${WORK}"' EXIT
+
+skip() { echo "SKIP: $*"; exit "${SKIP}"; }
+fail() { echo "FAIL: $*"; exit 1; }
+
+# ---------------------------------------------------------------- environment
+[ "${AKBASIC_SKIP_INTERACTIVE:-0}" = "1" ] && skip "AKBASIC_SKIP_INTERACTIVE=1"
+[ -n "${DISPLAY:-}" ] || skip "no DISPLAY; this needs a real X server, not the dummy driver"
+command -v xdotool >/dev/null 2>&1 || skip "xdotool is not installed"
+command -v script  >/dev/null 2>&1 || skip "script(1) is not installed"
+xdotool getactivewindow >/dev/null 2>&1 || skip "no window manager is answering on ${DISPLAY}"
+
+# script(1) gives the driver a pty for stdin, which is what makes it choose the
+# *window* as its console. Redirected stdin is a deliberate signal to read the
+# pipe instead -- see run_akgl() in src/main.c -- and under CTest stdin is never
+# a terminal, so without this the driver would ignore the keyboard entirely and
+# the test would be measuring nothing.
+OUT="${WORK}/typescript"
+script -qefc "${BASIC}" "${OUT}" >/dev/null 2>&1 &
+DRIVER=$!
+
+# shellcheck disable=SC2317  # reached only through the EXIT trap below
+cleanup_driver() {
+    kill "${DRIVER}" 2>/dev/null
+    wait "${DRIVER}" 2>/dev/null
+}
+trap 'cleanup_driver; rm -rf "${WORK}"' EXIT
+
+# ------------------------------------------------------------------ the window
+# --sync blocks until it appears rather than sleeping and hoping.
+WID="$(timeout 20 xdotool search --sync --onlyvisible --name '^BASIC$' 2>/dev/null | head -1)"
+[ -n "${WID}" ] || skip "the BASIC window never appeared (headless, or a WM that does not map it)"
+
+xdotool windowactivate --sync "${WID}" >/dev/null 2>&1
+xdotool windowfocus    --sync "${WID}" >/dev/null 2>&1
+FOCUS="$(xdotool getwindowfocus 2>/dev/null)"
+[ "${FOCUS}" = "${WID}" ] || skip "could not give the window keyboard focus (got '${FOCUS}', wanted '${WID}')"
+
+# ------------------------------------------------------------------- the typing
+# Poll for expected output instead of sleeping a guessed interval: a fixed sleep
+# is either flaky or slow, and usually both.
+await() {
+    local want="$1" limit="${2:-15}" i=0
+    while [ "${i}" -lt $((limit * 10)) ]; do
+        if tr -d '\r' < "${OUT}" 2>/dev/null | grep -qF "${want}"; then
+            return 0
+        fi
+        sleep 0.1
+        i=$((i + 1))
+    done
+    return 1
+}
+
+type_line() {
+    xdotool type --clearmodifiers --delay 30 "$1"
+    xdotool key  --clearmodifiers Return
+}
+
+await "READY" 20 || skip "the interpreter never reached its prompt"
+
+# A string literal on purpose: the double quote is the character that was
+# unreachable before the keystroke ring carried composed text, and a BASIC
+# program that cannot contain a string is not much of a BASIC.
+type_line '10 PRINT "TYPED OK"'
+type_line 'RUN'
+
+if ! await "TYPED OK" 15; then
+    echo "--- what the driver actually wrote ---"
+    tr -d '\r' < "${OUT}" 2>/dev/null | sed -n '1,20p'
+    fail "typing at the window produced nothing: the keyboard path is broken"
+fi
+
+# Lower case has to survive too. It could not before libakgl 0.3.0, because a
+# keycode cannot express shift and the editor folded everything to upper case.
+type_line '20 PRINT "lower"'
+type_line 'RUN'
+if ! await "lower" 15; then
+    echo "--- what the driver actually wrote ---"
+    tr -d '\r' < "${OUT}" 2>/dev/null | sed -n '1,20p'
+    fail "lower case did not survive the keyboard: composed text is not reaching the editor"
+fi
+
+type_line 'QUIT'
+await "" 1 >/dev/null 2>&1 || true
+
+echo "PASS: typed at a real focused window and the interpreter ran it"
+exit 0