Merge pull request #122 from kaste/nicer-matcher-reprs

Author: kaste

mockito/matchers.py

@@ -60,6 +60,7 @@
 """
 
 from abc import ABC, abstractmethod
+import functools
 import re
 builtin_any = any
 
@@ -137,15 +138,46 @@ def matches(self, arg):
             return True
 
     def __repr__(self):
-        return "<Any: %s>" % self.wanted_type
+        return "<Any: %s>" % _any_wanted_type_label(self.wanted_type)
+
+
+def _any_wanted_type_label(wanted_type):
+    if isinstance(wanted_type, type):
+        return _type_label(wanted_type)
+
+    if (
+        isinstance(wanted_type, tuple)
+        and all(isinstance(t, type) for t in wanted_type)
+    ):
+        items = [_type_label(t) for t in wanted_type]
+        if len(items) == 1:
+            return '(%s,)' % items[0]
+        return '(%s)' % ', '.join(items)
+
+    return _safe_repr(wanted_type)
+
+
+def _type_label(type_):
+    module = _safe_getattr(type_, '__module__')
+    qualname = _safe_getattr(type_, '__qualname__') or _safe_getattr(type_, '__name__')
+    if qualname is None:
+        return _safe_repr(type_)
+
+    if module is None or module == 'builtins':
+        return qualname
+
+    return '%s.%s' % (module, qualname)
 
 
 class ValueMatcher(Matcher):
     def __init__(self, value):
         self.value = value
 
     def __repr__(self):
-        return "<%s: %s>" % (self.__class__.__name__, self.value)
+        return "<%s: %s>" % (
+            self.__class__.__name__,
+            _safe_repr(self.value),
+        )
 
 
 class Eq(ValueMatcher):
@@ -223,7 +255,93 @@ def matches(self, arg):
         return self.predicate(arg)
 
     def __repr__(self):
-        return "<ArgThat>"
+        return "<ArgThat: %s>" % _arg_that_predicate_label(self.predicate)
+
+
+def _arg_that_predicate_label(predicate):
+    try:
+        return _arg_that_predicate_label_unchecked(predicate)
+    except Exception:
+        predicate_class = _safe_getattr(
+            _safe_getattr(predicate, '__class__'),
+            '__name__',
+        )
+        if predicate_class is None:
+            return 'callable'
+
+        return 'callable %s' % predicate_class
+
+
+def _arg_that_predicate_label_unchecked(predicate):
+    if isinstance(predicate, functools.partial):
+        return _arg_that_partial_label(predicate)
+
+    function_line = _line_of_callable(predicate)
+    function_name = _safe_getattr(predicate, '__name__')
+    if function_name is not None:
+        if function_name == '<lambda>':
+            return _label_with_line('lambda', function_line)
+        return _label_with_line('def %s' % function_name, function_line)
+
+    predicate_class = _safe_getattr(
+        _safe_getattr(predicate, '__class__'),
+        '__name__',
+    )
+    if predicate_class is None:
+        predicate_class = 'object'
+
+    call = _safe_getattr(predicate, '__call__')
+    call_line = _line_of_callable(call)
+    return _label_with_line(
+        'callable %s.__call__' % predicate_class,
+        call_line,
+    )
+
+
+def _arg_that_partial_label(predicate):
+    partial_func = _safe_getattr(predicate, 'func')
+    partial_name = _safe_getattr(partial_func, '__name__')
+
+    if partial_name is not None:
+        return 'partial %s' % partial_name
+
+    return 'partial'
+
+
+def _line_of_callable(value):
+    if value is None:
+        return None
+
+    func = _safe_getattr(value, '__func__', value)
+    code = _safe_getattr(func, '__code__')
+    if code is None:
+        return None
+
+    return _safe_getattr(code, 'co_firstlineno')
+
+
+def _safe_getattr(value, name, default=None):
+    try:
+        return getattr(value, name)
+    except Exception:
+        return default
+
+
+def _safe_repr(value):
+    try:
+        return repr(value)
+    except Exception:
+        try:
+            return object.__repr__(value)
+        except Exception:
+            return '<unrepresentable>'
+
+
+def _label_with_line(label, line_number):
+    if line_number is None:
+        return label
+
+    return '%s at line %s' % (label, line_number)
 
 
 class Contains(Matcher):
@@ -236,24 +354,41 @@ def matches(self, arg):
         return self.sub and len(self.sub) > 0 and arg.find(self.sub) > -1
 
     def __repr__(self):
-        return "<Contains: '%s'>" % self.sub
+        return "<Contains: %s>" % _safe_repr(self.sub)
 
 
 class Matches(Matcher):
     def __init__(self, regex, flags=0):
         self.regex = re.compile(regex, flags)
+        self.flags = _explicit_regex_flags(regex, flags)
 
     def matches(self, arg):
         if not isinstance(arg, str):
             return
         return self.regex.match(arg) is not None
 
     def __repr__(self):
-        if self.regex.flags:
-            return "<Matches: %s flags=%d>" % (self.regex.pattern,
-                                               self.regex.flags)
+        if self.flags:
+            return "<Matches: %r flags=%d>" % (self.regex.pattern, self.flags)
         else:
-            return "<Matches: %s>" % self.regex.pattern
+            return "<Matches: %r>" % self.regex.pattern
+
+
+def _explicit_regex_flags(regex, flags):
+    if flags:
+        return flags
+
+    compiled_flags = _safe_getattr(regex, 'flags')
+    pattern = _safe_getattr(regex, 'pattern')
+    if compiled_flags is None or pattern is None:
+        return 0
+
+    try:
+        baseline_flags = re.compile(pattern).flags
+    except Exception:
+        return compiled_flags
+
+    return compiled_flags & ~baseline_flags
 
 
 class ArgumentCaptor(Matcher, Capturing):

tests/matcher_repr_test.py

@@ -0,0 +1,169 @@
+from functools import partial
+import re
+
+import numpy as np
+
+from mockito import and_, any as any_, arg_that, contains, eq, gt, matches, not_, or_
+
+
+def test_value_matchers_use_repr_for_string_values():
+    assert repr(eq("foo")) == "<Eq: 'foo'>"
+
+
+def test_composed_matchers_include_quoted_nested_values():
+    assert repr(not_(eq("foo"))) == "<Not: <Eq: 'foo'>>"
+    assert repr(and_(eq("foo"), gt(1))) == "<And: [<Eq: 'foo'>, <Gt: 1>]>"
+    assert repr(or_(eq("foo"), gt(1))) == "<Or: [<Eq: 'foo'>, <Gt: 1>]>"
+
+
+def test_any_repr_uses_pretty_names_for_types():
+    assert repr(any_(int)) == "<Any: int>"
+    assert repr(any_((int, str))) == "<Any: (int, str)>"
+
+
+def test_any_repr_quotes_non_type_values():
+    assert repr(any_("foo")) == "<Any: 'foo'>"
+
+
+def test_any_repr_handles_types_with_broken_introspection():
+    class EvilMeta(type):
+        def __getattribute__(cls, name):
+            if name in {'__module__', '__qualname__', '__name__'}:
+                raise RuntimeError('boom')
+            return super().__getattribute__(name)
+
+    class Evil(metaclass=EvilMeta):
+        pass
+
+    matcher_repr = repr(any_(Evil))
+    assert matcher_repr.startswith("<Any: <class '")
+    assert "Evil" in matcher_repr
+
+
+def test_any_repr_handles_values_with_broken_repr():
+    class BrokenRepr:
+        def __repr__(self):
+            raise RuntimeError('boom')
+
+    matcher_repr = repr(any_(BrokenRepr()))
+    assert matcher_repr.startswith('<Any: <')
+    assert 'BrokenRepr object' in matcher_repr
+
+
+def test_value_matcher_repr_handles_values_with_broken_repr():
+    class BrokenRepr:
+        def __repr__(self):
+            raise RuntimeError('boom')
+
+    matcher_repr = repr(eq(BrokenRepr()))
+    assert matcher_repr.startswith('<Eq: <')
+    assert 'BrokenRepr object' in matcher_repr
+
+
+def test_contains_repr_handles_values_with_broken_repr():
+    class BrokenRepr:
+        def __repr__(self):
+            raise RuntimeError('boom')
+
+    matcher_repr = repr(contains(BrokenRepr()))
+    assert matcher_repr.startswith('<Contains: <')
+    assert 'BrokenRepr object' in matcher_repr
+
+
+def test_contains_repr_uses_safe_quoted_substring():
+    assert repr(contains("a'b")) == "<Contains: \"a'b\">"
+
+
+def test_matches_repr_shows_only_explicit_flags():
+    assert repr(matches("f..")) == "<Matches: 'f..'>"
+    assert repr(matches("f..", re.IGNORECASE)) == (
+        f"<Matches: 'f..' flags={int(re.IGNORECASE)}>"
+    )
+
+
+def test_matches_repr_shows_flags_for_compiled_patterns():
+    compiled = re.compile('f..', re.IGNORECASE)
+
+    assert repr(matches(compiled)) == (
+        f"<Matches: 'f..' flags={int(re.IGNORECASE)}>"
+    )
+
+
+def test_arg_that_repr_includes_named_function_name():
+    # Predicate display name: "def is_positive"
+    def is_positive(value):
+        return value > 0
+
+    matcher = arg_that(is_positive)
+
+    assert repr(matcher) == (
+        f"<ArgThat: def is_positive at line {is_positive.__code__.co_firstlineno}>"
+    )
+
+
+def test_arg_that_repr_includes_lambda_name():
+    # Predicate display name: "lambda"
+    predicate = lambda value: value > 0
+    matcher = arg_that(predicate)
+
+    assert repr(matcher) == (
+        f"<ArgThat: lambda at line {predicate.__code__.co_firstlineno}>"
+    )
+
+
+def test_arg_that_repr_for_callable_instance_includes_class_name():
+    # Predicate display name: "callable IsPositive.__call__"
+    class IsPositive:
+        def __call__(self, value):
+            return value > 0
+
+    predicate = IsPositive()
+    matcher = arg_that(predicate)
+
+    assert repr(matcher) == (
+        "<ArgThat: callable IsPositive.__call__ at line "
+        f"{predicate.__call__.__func__.__code__.co_firstlineno}>"
+    )
+
+
+def test_arg_that_repr_for_builtin_callable_has_no_line_number():
+    matcher = arg_that(len)
+
+    assert repr(matcher) == "<ArgThat: def len>"
+
+
+def test_arg_that_repr_for_partial_uses_underlying_function_name():
+    predicate = partial(pow, exp=2)
+    matcher = arg_that(predicate)
+
+    assert repr(matcher) == "<ArgThat: partial pow>"
+
+
+def test_arg_that_repr_for_numpy_ufunc_uses_function_name_without_line():
+    matcher = arg_that(np.isfinite)
+
+    assert repr(matcher) == "<ArgThat: def isfinite>"
+
+
+def test_arg_that_repr_for_partial_numpy_function_uses_wrapped_name():
+    predicate = partial(np.allclose, b=0.0)
+    matcher = arg_that(predicate)
+
+    assert repr(matcher) == "<ArgThat: partial allclose>"
+
+
+def test_arg_that_repr_handles_callables_with_broken_name_introspection():
+    class BrokenNameCallable:
+        def __getattribute__(self, name):
+            if name == '__name__':
+                raise RuntimeError("boom")
+            return super().__getattribute__(name)
+
+        def __call__(self, value):
+            return value > 0
+
+    matcher = arg_that(BrokenNameCallable())
+
+    matcher_repr = repr(matcher)
+    assert matcher_repr.startswith("<ArgThat: callable BrokenNameCallable")
+    assert "__name__" not in matcher_repr