probe: show mcpp new, POSIX temp path

Author: speak-agent

.github/workflows/probe-old-engine-msvc-sysroot.yml

@@ -24,12 +24,14 @@ jobs:
           export MCPP_VENDORED_XLINGS="$XLINGS_BIN"
           "$MCPP" --version
           "$MCPP" self config --mirror GLOBAL
-          reg="$MCPP_HOME/registry/data/xpkgs"
+          reg="$(cygpath -u "$MCPP_HOME")/registry/data/xpkgs"
+          tmp="$(cygpath -u "$RUNNER_TEMP")"
           probe() {
-            local name=$1 value=$2 d="$RUNNER_TEMP/p-$name"
+            local name=$1 value=$2 d="$tmp/p-$1"
             rm -rf "$d"; mkdir -p "$d"; cd "$d"
-            "$MCPP" new hello > /dev/null 2>&1; cd hello
-            [ -n "$value" ] && printf '\n[target.x86_64-windows-msvc]\nsysroot = "%s"\n' "$value" >> mcpp.toml
+            "$MCPP" new hello || { echo "RESULT $name: mcpp new failed"; return 0; }
+            cd hello
+            if [ -n "$value" ]; then printf '\n[target.x86_64-windows-msvc]\nsysroot = "%s"\n' "$value" >> mcpp.toml; fi
             echo "::group::$name: mcpp.toml"; cat mcpp.toml; echo "::endgroup::"
             { ls "$reg" 2>/dev/null || true; } | sort > before.txt
             set +e