Nan Shao

"""Unit tests (mocked Binary Ninja) for analysis modules:
- bninja/analysis/cfg.py — CFGAnalysis
- bninja/analysis/disassembly.py — DisassemblyAnalysis
- bninja/analysis/low_level.py — LowLevelAnalysis
"""
import sys
import pytest
from unittest.mock import MagicMock

from tests.unit.conftest_binja_stubs import (
    install_binja_stubs,
    BranchType,
    InstructionTextTokenType,
    MockBasicBlock,
    MockEdge,
    MockFunction,
    MockToken,
    MockDisassemblyLine,
    MockBinaryView,
    MockSymbol,
    SymbolType,
    LowLevelILOperation,
)

install_binja_stubs()

from redb.extractors.decompiler.bninja.analysis.cfg import CFGAnalysis
from redb.extractors.decompiler.bninja.analysis.disassembly import DisassemblyAnalysis
from redb.extractors.decompiler.bninja.arch.x86 import Arch_x86


# ============================================================================
# 9a. CFGAnalysis
# ============================================================================


class TestCFGCyclomaticComplexity:
    def test_cyclomatic_complexity_linear(self):
        """Single block, no edges: E - N + 2 = 0 - 1 + 2 = 1."""
        block = MockBasicBlock(start=0x1000, end=0x1010, outgoing_edges=[])
        func = MockFunction(start=0x1000, basic_blocks=[block])
        cfg = CFGAnalysis(func)
        result = cfg.extract_function_cfg()
        assert result["cyclomatic_complexity"] == 1

    def test_cyclomatic_complexity_branch(self):
        """Diamond: 4 blocks, 4 edges -> 4 - 4 + 2 = 2."""
        entry = MockBasicBlock(start=0x1000, end=0x1010)
        true_b = MockBasicBlock(start=0x1010, end=0x1020)
        false_b = MockBasicBlock(start=0x1020, end=0x1030)
        merge = MockBasicBlock(start=0x1030, end=0x1040)

        entry.outgoing_edges = [MockEdge(target=true_b), MockEdge(target=false_b)]
        true_b.outgoing_edges = [MockEdge(target=merge)]
        false_b.outgoing_edges = [MockEdge(target=merge)]
        merge.outgoing_edges = []

        func = MockFunction(start=0x1000, basic_blocks=[entry, true_b, false_b, merge])
        cfg = CFGAnalysis(func)
        result = cfg.extract_function_cfg()
        assert result["cyclomatic_complexity"] == 2

    def test_cyclomatic_complexity_loop(self):
        """Loop: 3 blocks, 3 edges -> 3 - 3 + 2 = 2."""
        header = MockBasicBlock(start=0x1000, end=0x1010)
        body = MockBasicBlock(start=0x1010, end=0x1020)
        exit_b = MockBasicBlock(start=0x1020, end=0x1030)

        header.outgoing_edges = [MockEdge(target=body), MockEdge(target=exit_b)]
        body.outgoing_edges = [MockEdge(target=header)]
        exit_b.outgoing_edges = []

        func = MockFunction(start=0x1000, basic_blocks=[header, body, exit_b])
        cfg = CFGAnalysis(func)
        result = cfg.extract_function_cfg()
        assert result["cyclomatic_complexity"] == 2


class TestCFGExtractFunctionCFG:
    def _make_simple_cfg(self):
        """Create a simple two-block CFG for testing structure."""
        entry = MockBasicBlock(start=0x1000, end=0x1010)
        exit_b = MockBasicBlock(start=0x1010, end=0x1020)

        entry.outgoing_edges = [MockEdge(source=entry, target=exit_b, edge_type=BranchType.UnconditionalBranch)]
        exit_b.incoming_edges = [MockEdge(source=entry, target=exit_b)]
        exit_b.outgoing_edges = []
        entry.incoming_edges = []

        func = MockFunction(start=0x1000, basic_blocks=[entry, exit_b])
        return func

    def test_extract_function_cfg_structure(self):
        func = self._make_simple_cfg()
        cfg = CFGAnalysis(func)
        result = cfg.extract_function_cfg()
        assert "function_address" not in result
        # New schema: no "blocks" or "measures" nesting
        assert "blocks" not in result
        assert "measures" not in result

    def test_function_cfg_new_keys(self):
        """Assert all expected keys are present in the new output dict."""
        func = self._make_simple_cfg()
        cfg = CFGAnalysis(func)
        result = cfg.extract_function_cfg()
        expected_keys = [
            "cfg_topology_hash",
            "block_count",
            "edge_count",
            "llil_total_operations",
            "call_count",
            "cyclomatic_complexity",
            "loop_count",
            "max_depth",
            "max_fan_out",
            "md_index_topdown",
            "md_index_bottomup",
            "prime_product_llil",
            "cfg_feature_tlsh",
            "wl_minhash",
            "bb_features",
            "cfg_adjacency",
        ]
        for key in expected_keys:
            assert key in result, f"Missing key: {key}"

    def test_returns_none_for_empty_blocks(self):
        func = MockFunction(start=0x1000, basic_blocks=[])
        cfg = CFGAnalysis(func)
        assert cfg.extract_function_cfg() is None


class TestCFGTopologyHash:
    def _make_two_block_cfg(self):
        entry = MockBasicBlock(start=0x1000, end=0x1010)
        exit_b = MockBasicBlock(start=0x1010, end=0x1020)
        entry.outgoing_edges = [MockEdge(target=exit_b)]
        exit_b.outgoing_edges = []
        return MockFunction(start=0x1000, basic_blocks=[entry, exit_b])

    def test_topology_hash_is_16_bytes(self):
        func = self._make_two_block_cfg()
        cfg = CFGAnalysis(func)
        result = cfg.extract_function_cfg()
        assert isinstance(result["cfg_topology_hash"], bytes)
        assert len(result["cfg_topology_hash"]) == 16

    def test_topology_hash_deterministic(self):
        func = self._make_two_block_cfg()
        r1 = CFGAnalysis(func).extract_function_cfg()
        r2 = CFGAnalysis(func).extract_function_cfg()
        assert r1["cfg_topology_hash"] == r2["cfg_topology_hash"]


class TestCFGLoopCount:
    def test_no_loops(self):
        entry = MockBasicBlock(start=0x1000, end=0x1010)
        exit_b = MockBasicBlock(start=0x1010, end=0x1020)
        entry.outgoing_edges = [MockEdge(target=exit_b)]
        exit_b.outgoing_edges = []
        func = MockFunction(start=0x1000, basic_blocks=[entry, exit_b])
        result = CFGAnalysis(func).extract_function_cfg()
        assert result["loop_count"] == 0

    def test_single_loop(self):
        header = MockBasicBlock(start=0x1000, end=0x1010)
        body = MockBasicBlock(start=0x1010, end=0x1020)
        exit_b = MockBasicBlock(start=0x1020, end=0x1030)
        header.outgoing_edges = [MockEdge(target=body), MockEdge(target=exit_b)]
        body.outgoing_edges = [MockEdge(target=header)]
        exit_b.outgoing_edges = []
        func = MockFunction(start=0x1000, basic_blocks=[header, body, exit_b])
        result = CFGAnalysis(func).extract_function_cfg()
        assert result["loop_count"] == 1


class TestCFGMaxDepth:
    def test_max_depth_linear(self):
        entry = MockBasicBlock(start=0x1000, end=0x1010)
        b1 = MockBasicBlock(start=0x1010, end=0x1020)
        b2 = MockBasicBlock(start=0x1020, end=0x1030)
        entry.outgoing_edges = [MockEdge(target=b1)]
        b1.outgoing_edges = [MockEdge(target=b2)]
        b2.outgoing_edges = []
        func = MockFunction(start=0x1000, basic_blocks=[entry, b1, b2])
        result = CFGAnalysis(func).extract_function_cfg()
        assert result["max_depth"] == 2

    def test_max_depth_single_block(self):
        block = MockBasicBlock(start=0x1000, end=0x1010, outgoing_edges=[])
        func = MockFunction(start=0x1000, basic_blocks=[block])
        result = CFGAnalysis(func).extract_function_cfg()
        assert result["max_depth"] == 0


class TestCFGCollectBlockLlilOps:
    """Test that _collect_block_llil_ops correctly maps LLIL data to native blocks."""

    def test_llil_fields_nonzero_with_mock_llil(self):
        """When LLIL is available, llil_total_operations and call_count should be non-zero."""
        # Two native blocks
        entry = MockBasicBlock(start=0x1000, end=0x1010)
        exit_b = MockBasicBlock(start=0x1010, end=0x1020)
        entry.outgoing_edges = [MockEdge(target=exit_b)]
        exit_b.outgoing_edges = []

        # LLIL instructions: SET_REG, CALL in first block; STORE, RET in second
        llil_instrs_1 = [
            MockLLILInstruction(LowLevelILOperation.LLIL_SET_REG),
            MockLLILInstruction(LowLevelILOperation.LLIL_CALL),
        ]
        llil_instrs_2 = [
            MockLLILInstruction(LowLevelILOperation.LLIL_STORE),
            MockLLILInstruction(LowLevelILOperation.LLIL_RET),
        ]

        # LLIL basic blocks map back to native blocks via source_block
        llil_bb1 = MockLLILBasicBlock(llil_instrs_1, source_block=entry)
        llil_bb2 = MockLLILBasicBlock(llil_instrs_2, source_block=exit_b)
        llil_func = MockLLILFunction([llil_bb1, llil_bb2])

        func = MockFunction(start=0x1000, basic_blocks=[entry, exit_b], llil=llil_func)
        result = CFGAnalysis(func, llil_function=llil_func).extract_function_cfg()

        assert result["llil_total_operations"] == 4
        assert result["call_count"] == 1
        assert result["prime_product_llil"] != 0

    def test_llil_none_gives_zero_fields(self):
        """Without LLIL, LLIL-dependent fields should be zero."""
        block = MockBasicBlock(start=0x1000, end=0x1010, outgoing_edges=[])
        func = MockFunction(start=0x1000, basic_blocks=[block])
        result = CFGAnalysis(func).extract_function_cfg()

        assert result["llil_total_operations"] == 0
        assert result["call_count"] == 0
        assert result["prime_product_llil"] == 0

    def test_bb_features_with_llil(self):
        """bb_features should reflect LLIL instruction categories when LLIL is available."""
        block = MockBasicBlock(start=0x1000, end=0x1010, outgoing_edges=[])

        llil_instrs = [
            MockLLILInstruction(LowLevelILOperation.LLIL_ADD),
            MockLLILInstruction(LowLevelILOperation.LLIL_LOAD),
            MockLLILInstruction(LowLevelILOperation.LLIL_CALL),
        ]
        llil_bb = MockLLILBasicBlock(llil_instrs, source_block=block)
        llil_func = MockLLILFunction([llil_bb])

        func = MockFunction(start=0x1000, basic_blocks=[block])
        result = CFGAnalysis(func, llil_function=llil_func).extract_function_cfg()

        feats = result["bb_features"]
        assert len(feats) == 1
        assert feats[0][0] == 3  # instruction count = 3
        # At least one non-zero category count (not all OTHER)
        category_counts = feats[0][1:7]
        assert sum(category_counts) > 0


# ============================================================================
# 9b. DisassemblyAnalysis
# ============================================================================


class TestDisassemblyAnalysisGetJson:
    def _make_analysis(self, instructions=None, basic_blocks=None):
        arch = Arch_x86()
        if instructions is None:
            instructions = [
                (
                    [
                        MockToken("push", InstructionTextTokenType.InstructionToken),
                        MockToken(" ", InstructionTextTokenType.TextToken),
                        MockToken("rbp", InstructionTextTokenType.RegisterToken),
                    ],
                    0x1000,
                ),
                (
                    [
                        MockToken("mov", InstructionTextTokenType.InstructionToken),
                        MockToken(" ", InstructionTextTokenType.TextToken),
                        MockToken("rsp", InstructionTextTokenType.RegisterToken),
                    ],
                    0x1003,
                ),
            ]
        if basic_blocks is None:
            basic_blocks = [MockBasicBlock(
                start=0x1000, end=0x1010,
                disassembly_text=[MockDisassemblyLine([MockToken("push rbp")])]
            )]

        func = MockFunction(
            name="test_func",
            start=0x1000,
            basic_blocks=basic_blocks,
            instructions=instructions,
            symbol=MockSymbol(symbol_type=SymbolType.FunctionSymbol, name="test_func"),
            stack_adjustment=MagicMock(value=-8),
            mlil=None,
        )
        bv = MockBinaryView()
        logger = MagicMock()
        return DisassemblyAnalysis(arch, func, bv, logger)

    def test_get_json_basic_structure(self):
        da = self._make_analysis()
        result, errors = da.get_json()
        expected_keys = [
            "disassembled_function_hash",
            "disassembled_function",
            "disassembled_function_no_addresses",
            "disassembled_function_name",
            "disassembled_function_address",
            "instructions_count",
            "function_type",
            "instructions_types",
            "control_flow_count",
            "memory_access_pattern",
            "register_usage",
            "data_references_count",
        ]
        for key in expected_keys:
            assert key in result, f"Missing key: {key}"

    def test_get_json_hash_deterministic(self):
        da = self._make_analysis()
        r1, _ = da.get_json()
        da2 = self._make_analysis()
        r2, _ = da2.get_json()
        assert r1["disassembled_function_hash"] == r2["disassembled_function_hash"]


class TestDisassemblyCollectInstructionTypes:
    def test_collect_instruction_types(self):
        arch = Arch_x86()
        instructions = [
            ([MockToken("MOV", InstructionTextTokenType.InstructionToken)], 0x1000),
            ([MockToken("ADD", InstructionTextTokenType.InstructionToken)], 0x1001),
            ([MockToken("MOV", InstructionTextTokenType.InstructionToken)], 0x1002),
        ]
        func = MockFunction(start=0x1000, instructions=instructions, symbol=MockSymbol())
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        types = da.collect_instruction_types()
        assert "DATA_MOVEMENT" in types
        assert "ARITHMETIC" in types

    def test_collect_instruction_types_empty(self):
        arch = Arch_x86()
        func = MockFunction(start=0x1000, instructions=[], symbol=MockSymbol())
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        types = da.collect_instruction_types()
        assert types == {}


class TestDisassemblyMemoryPatterns:
    def _make_memory_instruction(self, tokens):
        return ([t for t in tokens], 0x1000)

    def test_collect_memory_patterns_stack(self):
        arch = Arch_x86()
        tokens = [
            MockToken("[", InstructionTextTokenType.BeginMemoryOperandToken),
            MockToken("RSP", InstructionTextTokenType.RegisterToken),
            MockToken("+0x8", InstructionTextTokenType.TextToken),
            MockToken("]", InstructionTextTokenType.EndMemoryOperandToken),
        ]
        instructions = [self._make_memory_instruction(tokens)]
        func = MockFunction(start=0x1000, instructions=instructions, symbol=MockSymbol())
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        patterns = da.collect_memory_patterns()
        assert "MEM_STACK" in patterns

    def test_collect_memory_patterns_direct(self):
        arch = Arch_x86()
        tokens = [
            MockToken("[", InstructionTextTokenType.BeginMemoryOperandToken),
            MockToken("0x402000", InstructionTextTokenType.TextToken),
            MockToken("]", InstructionTextTokenType.EndMemoryOperandToken),
        ]
        instructions = [self._make_memory_instruction(tokens)]
        func = MockFunction(start=0x1000, instructions=instructions, symbol=MockSymbol())
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        patterns = da.collect_memory_patterns()
        assert "MEM_DIRECT" in patterns

    def test_collect_memory_patterns_scaled(self):
        arch = Arch_x86()
        tokens = [
            MockToken("[", InstructionTextTokenType.BeginMemoryOperandToken),
            MockToken("RAX+RCX*4", InstructionTextTokenType.TextToken),
            MockToken("]", InstructionTextTokenType.EndMemoryOperandToken),
        ]
        instructions = [self._make_memory_instruction(tokens)]
        func = MockFunction(start=0x1000, instructions=instructions, symbol=MockSymbol())
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        patterns = da.collect_memory_patterns()
        assert "MEM_SCALED_INDEX" in patterns

    def test_collect_memory_patterns_base_offset(self):
        arch = Arch_x86()
        tokens = [
            MockToken("[", InstructionTextTokenType.BeginMemoryOperandToken),
            MockToken("RAX+0x10", InstructionTextTokenType.TextToken),
            MockToken("]", InstructionTextTokenType.EndMemoryOperandToken),
        ]
        instructions = [self._make_memory_instruction(tokens)]
        func = MockFunction(start=0x1000, instructions=instructions, symbol=MockSymbol())
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        patterns = da.collect_memory_patterns()
        assert "MEM_BASE_OFFSET" in patterns


class TestDisassemblyRegisterUsage:
    def test_collect_register_usage_gpr(self):
        arch = Arch_x86()
        instructions = [
            ([MockToken("RAX", InstructionTextTokenType.RegisterToken)], 0x1000),
        ]
        func = MockFunction(start=0x1000, instructions=instructions, symbol=MockSymbol())
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        regs = da.collect_register_usage()
        assert "GPR" in regs

    def test_collect_register_usage_simd(self):
        arch = Arch_x86()
        instructions = [
            ([MockToken("XMM0", InstructionTextTokenType.RegisterToken)], 0x1000),
        ]
        func = MockFunction(start=0x1000, instructions=instructions, symbol=MockSymbol())
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        regs = da.collect_register_usage()
        assert "SIMD" in regs

    def test_collect_register_usage_fpu(self):
        arch = Arch_x86()
        instructions = [
            ([MockToken("ST0", InstructionTextTokenType.RegisterToken)], 0x1000),
        ]
        func = MockFunction(start=0x1000, instructions=instructions, symbol=MockSymbol())
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        regs = da.collect_register_usage()
        assert "FPU" in regs


class TestDisassemblyMisc:
    def test_count_data_references(self):
        arch = Arch_x86()
        func = MockFunction(start=0x1000, instructions=[], symbol=MockSymbol(), mlil=None)
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        assert da.count_data_references() == 0

    def test_compute_max_block_size(self):
        arch = Arch_x86()
        blocks = [
            MockBasicBlock(disassembly_text=[MockDisassemblyLine([]) for _ in range(3)]),
            MockBasicBlock(disassembly_text=[MockDisassemblyLine([]) for _ in range(5)]),
        ]
        func = MockFunction(start=0x1000, basic_blocks=blocks, instructions=[], symbol=MockSymbol())
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        assert da.compute_max_block_size() == 5

    def test_compute_num_calls(self):
        arch = Arch_x86()
        instructions = [
            ([MockToken("CALL", InstructionTextTokenType.InstructionToken)], 0x1000),
            ([MockToken("MOV", InstructionTextTokenType.InstructionToken)], 0x1005),
            ([MockToken("CALL", InstructionTextTokenType.InstructionToken)], 0x1010),
        ]
        func = MockFunction(start=0x1000, instructions=instructions, symbol=MockSymbol())
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        assert da.compute_num_calls() == 2

    def test_estimate_stack_size_value(self):
        arch = Arch_x86()
        stack = MagicMock()
        stack.value = -16
        func = MockFunction(start=0x1000, instructions=[], symbol=MockSymbol(), stack_adjustment=stack)
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        assert da.estimate_stack_size() == -16

    def test_estimate_stack_size_int(self):
        arch = Arch_x86()
        func = MockFunction(start=0x1000, instructions=[], symbol=MockSymbol(), stack_adjustment=-8)
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        assert da.estimate_stack_size() == -8

    def test_normalize_opcode(self):
        arch = Arch_x86()
        func = MockFunction(start=0x1000, instructions=[], symbol=MockSymbol())
        da = DisassemblyAnalysis(arch, func, MockBinaryView(), MagicMock())
        assert da.normalize_opcode("mov") == "MOV"
        assert da.normalize_opcode("PUSH") == "PUSH"


# ============================================================================
# 9c. LowLevelAnalysis (basic tests with mocked LLIL)
# ============================================================================


class MockLLILInstruction:
    """Mock LLIL instruction for low_level.py tests."""
    def __init__(self, operation, operands=None, address=0):
        self.operation = operation
        self.operands = operands or []
        self.address = address

    def __str__(self):
        return f"LLIL_{self.operation}"


class MockLLILBasicBlock:
    def __init__(self, instructions, source_block=None):
        self._instructions = instructions
        self.source_block = source_block

    def __iter__(self):
        return iter(self._instructions)


class MockLLILFunction:
    def __init__(self, basic_blocks):
        self.basic_blocks = basic_blocks
        self._instructions = []
        for bb in basic_blocks:
            self._instructions.extend(bb._instructions)

    @property
    def instructions(self):
        return iter(self._instructions)

    @property
    def source_function(self):
        mock = MagicMock()
        mock.start = 0x1000
        return mock


class TestLowLevelAnalysisCountControlFlow:
    def test_count_control_flow_instructions(self):
        from redb.extractors.decompiler.bninja.analysis.low_level import LowLevelAnalysis
        instrs = [
            MockLLILInstruction(LowLevelILOperation.LLIL_IF),
            MockLLILInstruction(LowLevelILOperation.LLIL_SET_REG),
            MockLLILInstruction(LowLevelILOperation.LLIL_CALL),
            MockLLILInstruction(LowLevelILOperation.LLIL_GOTO),
        ]
        bb = MockLLILBasicBlock(instrs)
        llil_func = MockLLILFunction([bb])

        func = MockFunction(start=0x1000, llil=llil_func, symbol=MockSymbol())
        func.low_level_il = None
        bv = MockBinaryView()
        bv.arch = MagicMock()
        bv.arch.stack_pointer = "sp"
        la = LowLevelAnalysis(func, bv, MagicMock())
        assert la.count_control_flow_instructions() == 3  # IF, CALL, GOTO


class TestLowLevelAnalysisNumCalls:
    def test_compute_num_calls_llil(self):
        from redb.extractors.decompiler.bninja.analysis.low_level import LowLevelAnalysis
        instrs = [
            MockLLILInstruction(LowLevelILOperation.LLIL_CALL),
            MockLLILInstruction(LowLevelILOperation.LLIL_TAILCALL),
            MockLLILInstruction(LowLevelILOperation.LLIL_SET_REG),
        ]
        bb = MockLLILBasicBlock(instrs)
        llil_func = MockLLILFunction([bb])

        func = MockFunction(start=0x1000, llil=llil_func, symbol=MockSymbol())
        func.low_level_il = None
        bv = MockBinaryView()
        la = LowLevelAnalysis(func, bv, MagicMock())
        assert la.compute_num_calls() == 2


class TestLowLevelAnalysisCollectNormalization:
    def test_collect_low_level(self):
        from redb.extractors.decompiler.bninja.analysis.low_level import LowLevelAnalysis
        instrs = [
            MockLLILInstruction(LowLevelILOperation.LLIL_SET_REG, address=0x1000),
            MockLLILInstruction(LowLevelILOperation.LLIL_STORE, address=0x1004),
        ]
        bb = MockLLILBasicBlock(instrs)
        llil_func = MockLLILFunction([bb])

        func = MockFunction(start=0x1000, llil=llil_func, symbol=MockSymbol())
        func.low_level_il = None
        bv = MockBinaryView()
        la = LowLevelAnalysis(func, bv, MagicMock())
        result, _ = la._collect_low_level_and_with_addr()
        assert len(result) == 2
        # Each item is a list of operation ints
        assert isinstance(result[0], list)

    def test_collect_low_level_with_addr_offset_clamping(self):
        from redb.extractors.decompiler.bninja.analysis.low_level import LowLevelAnalysis
        instrs = [
            MockLLILInstruction(LowLevelILOperation.LLIL_SET_REG, address=0x0FFF),  # Before function start
        ]
        bb = MockLLILBasicBlock(instrs)
        llil_func = MockLLILFunction([bb])

        func = MockFunction(start=0x1000, llil=llil_func, symbol=MockSymbol())
        func.low_level_il = None
        bv = MockBinaryView()
        la = LowLevelAnalysis(func, bv, MagicMock())
        _, result = la._collect_low_level_and_with_addr()
        assert len(result) == 1
        offset, _ = result[0]
        assert offset == 0  # Clamped to 0