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tests/ui-smoke/_lib/skip-if-missing.sh

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+#!/bin/bash
+# Shared "skip" predicate for ui-smoke tests.
+# runtests semantics: a `skip` script that returns non-zero causes the
+# test to be skipped. Per-test skip files invoke this.
+#
+# We only skip on xvfb-run absence (rare local dev env) or when the
+# GUI under test was not built (--disable-gui headless builds).
+# Python / typelib deps are declared in debian/control under !nocheck
+# so CI always has them; missing deps should fail the test loudly
+# rather than silently skip (BsAtHome / hdiethelm review, PR #3999).
+#
+# Usage: skip-if-missing.sh [gui-binary]
+set -u
+
+if ! command -v xvfb-run >/dev/null 2>&1; then
+    echo "skip: xvfb-run not installed" >&2
+    exit 1
+fi
+
+if [ $# -ge 1 ] && ! command -v "$1" >/dev/null 2>&1; then
+    echo "skip: $1 not built (headless build)" >&2
+    exit 1
+fi
+
+exit 0