test(04-01): add failing tests for script_generator RED phase

- test_render_install_returns_string: basic smoke test
- test_render_install_contains_pnputil: SCRPT-01 pnputil + Add-PrinterDriver
- test_render_install_print_config: SCRPT-01 duplex mode translation
- test_render_install_wow64_guard: SCRPT-05 WOW64 relaunch guard
- test_render_install_uac_guard: SCRPT-04 SYSTEM vs user + UAC elevation
- test_render_install_idempotency: SCRPT-01 idempotency checks
- test_render_install_booleans: SCRPT-01 boolean rendering

tests/test_script_generator.py

@@ -0,0 +1,94 @@
+"""Unit tests for script_generator.py — SCRPT-01, SCRPT-04, SCRPT-05."""
+import pytest
+from imptune.generators.script_generator import render_install
+
+
+SAMPLE_ARGS = dict(
+    printer_name="HP LaserJet 4000",
+    ip_address="192.168.1.10",
+    port_name="IP_192.168.1.10",
+    driver_name="HP Universal Printing PCL 6",
+    inf_filename="hpcu270u.inf",
+    duplex_mode="LongEdge",
+    color_mode=True,
+    paper_size="A4",
+    collate=True,
+)
+
+
+def test_render_install_returns_string():
+    """render_install returns a non-empty string."""
+    result = render_install(**SAMPLE_ARGS)
+    assert isinstance(result, str)
+    assert len(result) > 0
+
+
+def test_render_install_contains_pnputil():
+    """SCRPT-01: Output contains pnputil /add-driver and Add-PrinterDriver."""
+    result = render_install(**SAMPLE_ARGS)
+    assert "pnputil.exe /add-driver" in result
+    assert "Add-PrinterDriver" in result
+    assert "hpcu270u.inf" in result
+    assert "HP Universal Printing PCL 6" in result
+
+
+def test_render_install_print_config():
+    """SCRPT-01: Set-PrintConfiguration with translated duplex mode."""
+    # LongEdge -> TwoSidedLongEdge
+    result = render_install(**SAMPLE_ARGS)
+    assert "Set-PrintConfiguration" in result
+    assert "TwoSidedLongEdge" in result
+    assert "A4" in result
+
+    # ShortEdge -> TwoSidedShortEdge
+    result_short = render_install(**{**SAMPLE_ARGS, "duplex_mode": "ShortEdge"})
+    assert "TwoSidedShortEdge" in result_short
+
+    # OneSided -> OneSided (no change)
+    result_one = render_install(**{**SAMPLE_ARGS, "duplex_mode": "OneSided"})
+    assert "OneSided" in result_one
+    # Must NOT contain the two-sided variants when OneSided
+    assert "TwoSided" not in result_one
+
+
+def test_render_install_wow64_guard():
+    """SCRPT-05: WOW64 relaunch guard is present in the output."""
+    result = render_install(**SAMPLE_ARGS)
+    assert "PROCESSOR_ARCHITECTURE" in result
+    assert "SysNative" in result
+    # Guard must appear near the top (before pnputil)
+    wow64_pos = result.find("PROCESSOR_ARCHITECTURE")
+    pnputil_pos = result.find("pnputil.exe")
+    assert wow64_pos < pnputil_pos, "WOW64 guard must appear before pnputil"
+
+
+def test_render_install_uac_guard():
+    """SCRPT-04: SYSTEM vs user detection with UAC self-elevation."""
+    result = render_install(**SAMPLE_ARGS)
+    assert "IsSystem" in result
+    assert "Start-Process" in result
+    assert "-Verb Runas" in result or "Verb Runas" in result
+
+
+def test_render_install_idempotency():
+    """SCRPT-01: All add operations wrapped in idempotency checks."""
+    result = render_install(**SAMPLE_ARGS)
+    # Port idempotency
+    assert "Get-PrinterPort" in result
+    assert "Add-PrinterPort" in result
+    # Printer idempotency
+    assert "Get-Printer" in result
+    assert "Add-Printer" in result
+    # Port check must come before Add-PrinterPort
+    get_port_pos = result.find("Get-PrinterPort")
+    add_port_pos = result.find("Add-PrinterPort")
+    assert get_port_pos < add_port_pos, "Get-PrinterPort check must precede Add-PrinterPort"
+
+
+def test_render_install_booleans():
+    """Color and collate are rendered as $true / $false in the script."""
+    result_true = render_install(**SAMPLE_ARGS)  # color_mode=True, collate=True
+    assert "$true" in result_true
+
+    result_false = render_install(**{**SAMPLE_ARGS, "color_mode": False, "collate": False})
+    assert "$false" in result_false