test: Phase 113 if-only partial assign fixture + smokes (VM + LLVM)

- Add apps/tests/phase113_if_only_partial_assign_min.hako
  * Pattern: x=1; if flag==1 { x=2 } print(x)
  * Tests "preserve merge" on else side
- Add VM smoke: phase113_if_only_partial_assign_vm.sh
- Add LLVM EXE smoke: phase113_if_only_partial_assign_llvm_exe.sh
- Expected output: 1\n2 (flag=0 preserves, flag=1 updates)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/tests/phase113_if_only_partial_assign_min.hako

@@ -0,0 +1,27 @@
+// Phase 113: if-only partial assign (preserve merge on else side)
+
+static box Main {
+  main() {
+    local x
+    local flag
+
+    // First call: flag=0 → x stays 1 → print 1
+    flag = 0
+    x = 1
+    if flag == 1 {
+      x = 2
+    }
+    // else側は暗黙の "保持" (x keeps original value)
+    print(x)
+
+    // Second call: flag=1 → x becomes 2 → print 2
+    flag = 1
+    x = 1
+    if flag == 1 {
+      x = 2
+    }
+    print(x)
+
+    return "OK"
+  }
+}

tools/smokes/v2/profiles/integration/apps/phase113_if_only_partial_assign_llvm_exe.sh

@@ -0,0 +1,38 @@
+#!/bin/bash
+# Phase 113: if-only partial assign (LLVM EXE parity)
+
+source "$(dirname "$0")/../../../lib/test_runner.sh"
+source "$(dirname "$0")/../../../lib/llvm_exe_runner.sh"
+export SMOKES_USE_PYVM=0
+require_env || exit 2
+
+llvm_exe_preflight_or_skip || exit 0
+
+# Phase 97/98/100 SSOT: plugin dlopen check → build only if needed → dlopen recheck.
+FILEBOX_SO="$NYASH_ROOT/plugins/nyash-filebox-plugin/libnyash_filebox_plugin.so"
+MAPBOX_SO="$NYASH_ROOT/plugins/nyash-map-plugin/libnyash_map_plugin.so"
+STRINGBOX_SO="$NYASH_ROOT/plugins/nyash-string-plugin/libnyash_string_plugin.so"
+CONSOLEBOX_SO="$NYASH_ROOT/plugins/nyash-console-plugin/libnyash_console_plugin.so"
+INTEGERBOX_SO="$NYASH_ROOT/plugins/nyash-integer-plugin/libnyash_integer_plugin.so"
+
+LLVM_REQUIRED_PLUGINS=(
+  "FileBox|$FILEBOX_SO|nyash-filebox-plugin"
+  "MapBox|$MAPBOX_SO|nyash-map-plugin"
+  "StringBox|$STRINGBOX_SO|nyash-string-plugin"
+  "ConsoleBox|$CONSOLEBOX_SO|nyash-console-plugin"
+  "IntegerBox|$INTEGERBOX_SO|nyash-integer-plugin"
+)
+LLVM_PLUGIN_BUILD_LOG="/tmp/phase113_if_only_partial_assign_plugin_build.log"
+llvm_exe_ensure_plugins_or_fail || exit 1
+
+INPUT_HAKO="$NYASH_ROOT/apps/tests/phase113_if_only_partial_assign_min.hako"
+OUTPUT_EXE="$NYASH_ROOT/tmp/phase113_if_only_partial_assign_llvm_exe"
+
+EXPECTED=$'1\n2'
+EXPECTED_LINES=2
+LLVM_BUILD_LOG="/tmp/phase113_if_only_partial_assign_build.log"
+if llvm_exe_build_and_run_numeric_smoke; then
+  test_pass "phase113_if_only_partial_assign_llvm_exe: output matches expected (1\\n2)"
+else
+  exit 1
+fi

tools/smokes/v2/profiles/integration/apps/phase113_if_only_partial_assign_vm.sh

@@ -0,0 +1,56 @@
+#!/bin/bash
+# Phase 113: if-only partial assign (VM)
+#
+# Verifies that if-only lowering with partial assignment preserves original value on else side.
+
+source "$(dirname "$0")/../../../lib/test_runner.sh"
+export SMOKES_USE_PYVM=0
+require_env || exit 2
+
+PASS_COUNT=0
+FAIL_COUNT=0
+RUN_TIMEOUT_SECS=${RUN_TIMEOUT_SECS:-10}
+
+INPUT="$NYASH_ROOT/apps/tests/phase113_if_only_partial_assign_min.hako"
+
+echo "[INFO] Phase 113: if-only partial assign (VM) - $INPUT"
+
+set +e
+OUTPUT=$(timeout "$RUN_TIMEOUT_SECS" env \
+  NYASH_DISABLE_PLUGINS=1 \
+  HAKO_JOINIR_STRICT=1 \
+  "$NYASH_BIN" --backend vm "$INPUT" 2>&1)
+EXIT_CODE=$?
+set -e
+
+if [ "$EXIT_CODE" -eq 124 ]; then
+  echo "[FAIL] hakorune timed out (>${RUN_TIMEOUT_SECS}s)"
+  FAIL_COUNT=$((FAIL_COUNT + 1))
+elif [ "$EXIT_CODE" -eq 0 ]; then
+  EXPECTED=$'1\n2'
+  CLEAN=$(printf "%s\n" "$OUTPUT" | grep -E '^-?[0-9]+$' | head -n 2 | tr -d '\r')
+  if [ "$CLEAN" = "$EXPECTED" ]; then
+    echo "[PASS] Output verified: 1\\n2"
+    PASS_COUNT=$((PASS_COUNT + 1))
+  else
+    echo "[FAIL] Unexpected output (expected: 1\\n2)"
+    echo "[INFO] output (tail):"
+    echo "$OUTPUT" | tail -n 50 || true
+    FAIL_COUNT=$((FAIL_COUNT + 1))
+  fi
+else
+  echo "[FAIL] hakorune failed with exit code $EXIT_CODE"
+  echo "[INFO] output (tail):"
+  echo "$OUTPUT" | tail -n 50 || true
+  FAIL_COUNT=$((FAIL_COUNT + 1))
+fi
+
+echo "[INFO] PASS: $PASS_COUNT, FAIL: $FAIL_COUNT"
+
+if [ "$FAIL_COUNT" -eq 0 ]; then
+  test_pass "phase113_if_only_partial_assign_vm: All tests passed"
+  exit 0
+else
+  test_fail "phase113_if_only_partial_assign_vm: $FAIL_COUNT test(s) failed"
+  exit 1
+fi