cli_test_helper.py
python
| 1 | """Argparse-compatible CliRunner replacement for Muse test suite. |
| 2 | |
| 3 | Replaces ``typer.testing.CliRunner`` so tests can call ``runner.invoke(cli, |
| 4 | args)`` without modification after the typer → argparse migration. The first |
| 5 | argument (``cli``) is always ``None`` (a stub) after migration; it is accepted |
| 6 | but ignored, and ``muse.cli.app.main`` is always the target. |
| 7 | """ |
| 8 | |
| 9 | from __future__ import annotations |
| 10 | |
| 11 | import contextlib |
| 12 | import io |
| 13 | import os |
| 14 | import re |
| 15 | import sys |
| 16 | import traceback |
| 17 | |
| 18 | from muse.cli.app import main |
| 19 | |
| 20 | _ANSI_ESCAPE = re.compile(r"\x1b\[[0-9;]*m") |
| 21 | |
| 22 | |
| 23 | def _strip_ansi(text: str) -> str: |
| 24 | """Remove ANSI escape sequences — typer's CliRunner did this automatically.""" |
| 25 | return _ANSI_ESCAPE.sub("", text) |
| 26 | |
| 27 | |
| 28 | class _StdinWithBuffer(io.StringIO): |
| 29 | """Text-mode stdin backed by StringIO, with a ``.buffer`` BytesIO sibling. |
| 30 | |
| 31 | Accepts either a ``str`` (text) or ``bytes`` (binary). When binary is |
| 32 | provided the text surface is left empty — commands that read from |
| 33 | ``sys.stdin.buffer`` (e.g. ``unpack-objects``) get the raw bytes while |
| 34 | text-mode reads get an empty string. |
| 35 | """ |
| 36 | |
| 37 | def __init__(self, text: str | bytes) -> None: |
| 38 | if isinstance(text, bytes): |
| 39 | super().__init__("") |
| 40 | self.buffer = io.BytesIO(text) |
| 41 | else: |
| 42 | super().__init__(text) |
| 43 | self.buffer = io.BytesIO(text.encode()) |
| 44 | |
| 45 | def isatty(self) -> bool: |
| 46 | return False |
| 47 | |
| 48 | |
| 49 | class _StdoutCapture(io.StringIO): |
| 50 | """Text-mode stdout backed by StringIO, with a ``.buffer`` BytesIO sibling. |
| 51 | |
| 52 | Some plumbing commands (e.g. ``cat-object``) write raw bytes to |
| 53 | ``sys.stdout.buffer``. Subclassing ``StringIO`` makes this assignable to |
| 54 | ``sys.stdout`` (and passable to ``contextlib.redirect_stdout``) without |
| 55 | any type annotation workaround. Binary output is decoded and appended to |
| 56 | the text output in ``getvalue()``. |
| 57 | """ |
| 58 | |
| 59 | def __init__(self) -> None: |
| 60 | super().__init__() |
| 61 | self.buffer = io.BytesIO() |
| 62 | |
| 63 | def isatty(self) -> bool: |
| 64 | return False |
| 65 | |
| 66 | def getvalue(self) -> str: |
| 67 | text_out = super().getvalue() |
| 68 | bytes_out = self.buffer.getvalue() |
| 69 | if bytes_out: |
| 70 | try: |
| 71 | text_out += bytes_out.decode("utf-8", errors="replace") |
| 72 | except Exception: |
| 73 | pass |
| 74 | return text_out |
| 75 | |
| 76 | |
| 77 | def _restore_env(saved: dict[str, str | None]) -> None: |
| 78 | """Restore environment variables to their pre-invoke state.""" |
| 79 | for k, orig in saved.items(): |
| 80 | if orig is None: |
| 81 | os.environ.pop(k, None) |
| 82 | else: |
| 83 | os.environ[k] = orig |
| 84 | |
| 85 | |
| 86 | class InvokeResult: |
| 87 | """Mirrors the fields that typer.testing.Result exposed.""" |
| 88 | |
| 89 | def __init__( |
| 90 | self, |
| 91 | exit_code: int, |
| 92 | output: str, |
| 93 | stderr_output: str = "", |
| 94 | stdout_bytes: bytes = b"", |
| 95 | ) -> None: |
| 96 | self.exit_code = exit_code |
| 97 | self.output = output |
| 98 | self.stdout = output |
| 99 | self.stderr = stderr_output |
| 100 | self.stdout_bytes = stdout_bytes |
| 101 | self.exception: BaseException | None = None |
| 102 | |
| 103 | def __repr__(self) -> str: |
| 104 | return f"InvokeResult(exit_code={self.exit_code}, output={self.output!r})" |
| 105 | |
| 106 | |
| 107 | class CliRunner: |
| 108 | """Drop-in replacement for ``typer.testing.CliRunner``. |
| 109 | |
| 110 | Captures stdout and stderr, calls ``main(args)``, and returns an |
| 111 | ``InvokeResult`` whose interface matches the typer equivalent closely |
| 112 | enough for the existing test suite to run without changes. |
| 113 | |
| 114 | Honoured parameters: |
| 115 | - ``env``: key/value pairs set in ``os.environ`` for the duration of the |
| 116 | call and restored afterward. |
| 117 | - ``input``: string fed to ``sys.stdin`` (needed by ``unpack-objects``). |
| 118 | - ``catch_exceptions``: when False, exceptions propagate to the caller. |
| 119 | """ |
| 120 | |
| 121 | def invoke( |
| 122 | self, |
| 123 | _cli: None, |
| 124 | args: list[str], |
| 125 | catch_exceptions: bool = True, |
| 126 | input: str | bytes | None = None, |
| 127 | env: dict[str, str] | None = None, |
| 128 | ) -> InvokeResult: |
| 129 | """Invoke ``main(args)`` and return captured output + exit code.""" |
| 130 | # Apply caller-supplied env overrides; restore originals when done. |
| 131 | saved: dict[str, str | None] = {} |
| 132 | if env: |
| 133 | for k, v in env.items(): |
| 134 | saved[k] = os.environ.get(k) |
| 135 | os.environ[k] = v |
| 136 | |
| 137 | stdout_cap = _StdoutCapture() |
| 138 | stderr_buf = io.StringIO() |
| 139 | exit_code = 0 |
| 140 | |
| 141 | # Patch sys.stdin for commands that read from it (e.g. unpack-objects). |
| 142 | # _StdinWithBuffer subclasses StringIO so the assignment is well-typed. |
| 143 | orig_stdin = sys.stdin |
| 144 | if input is not None: |
| 145 | sys.stdin = _StdinWithBuffer(input) |
| 146 | |
| 147 | try: |
| 148 | with ( |
| 149 | contextlib.redirect_stdout(stdout_cap), |
| 150 | contextlib.redirect_stderr(stderr_buf), |
| 151 | ): |
| 152 | main(list(args)) |
| 153 | except SystemExit as exc: |
| 154 | raw = exc.code |
| 155 | if isinstance(raw, int): |
| 156 | exit_code = raw |
| 157 | elif hasattr(raw, "value"): |
| 158 | exit_code = int(raw.value) |
| 159 | elif raw is None: |
| 160 | exit_code = 0 |
| 161 | else: |
| 162 | exit_code = int(raw) |
| 163 | except Exception as exc: |
| 164 | if not catch_exceptions: |
| 165 | sys.stdin = orig_stdin |
| 166 | _restore_env(saved) |
| 167 | raise |
| 168 | stderr_buf.write(traceback.format_exc()) |
| 169 | exit_code = 1 |
| 170 | result = InvokeResult( |
| 171 | exit_code, |
| 172 | _strip_ansi(stdout_cap.getvalue() + stderr_buf.getvalue()), |
| 173 | _strip_ansi(stderr_buf.getvalue()), |
| 174 | stdout_bytes=stdout_cap.buffer.getvalue(), |
| 175 | ) |
| 176 | result.exception = exc |
| 177 | sys.stdin = orig_stdin |
| 178 | _restore_env(saved) |
| 179 | return result |
| 180 | finally: |
| 181 | sys.stdin = orig_stdin |
| 182 | _restore_env(saved) |
| 183 | |
| 184 | raw_bytes = stdout_cap.buffer.getvalue() |
| 185 | combined = _strip_ansi(stdout_cap.getvalue() + stderr_buf.getvalue()) |
| 186 | return InvokeResult( |
| 187 | exit_code, |
| 188 | combined, |
| 189 | _strip_ansi(stderr_buf.getvalue()), |
| 190 | stdout_bytes=raw_bytes, |
| 191 | ) |