Rename OptionOverrideProxy to OptionsView and move to coredata

Coredata is where all option handling is done so it makes sense there.
It is a view on a list of options for a given subproject and with
optional overrides. This change prepare for using that view in a more
generic way in the future.

4 files changed, 48 insertions, 58 deletions

diff --git a/mesonbuild/build.py b/mesonbuild/build.py
index 8fed78531..edec75d90 100644
--- a/mesonbuild/build.py
+++ b/mesonbuild/build.py
@@ -34,7 +34,7 @@ from .mesonlib import (
     File, MesonException, MachineChoice, PerMachine, OrderedSet, listify,
     extract_as_list, typeslistify, stringlistify, classify_unity_sources,
     get_filenames_templates_dict, substitute_values, has_path_sep,
-    OptionKey, PerMachineDefaultable, OptionOverrideProxy,
+    OptionKey, PerMachineDefaultable,
     MesonBugException, EnvironmentVariables, pickle_load,
 )
 from .compilers import (
@@ -535,7 +535,7 @@ class Target(HoldableObject, metaclass=abc.ABCMeta):
                    for k, v in overrides.items()}
         else:
             ovr = {}
-        self.options = OptionOverrideProxy(ovr, self.environment.coredata.options, self.subproject)
+        self.options = coredata.OptionsView(self.environment.coredata.options, self.subproject, ovr)
         # XXX: this should happen in the interpreter
         if has_path_sep(self.name):
             # Fix failing test 53 when this becomes an error.
@@ -655,7 +655,7 @@ class Target(HoldableObject, metaclass=abc.ABCMeta):
             else:
                 self.options.overrides[k] = v
 
-    def get_options(self) -> OptionOverrideProxy:
+    def get_options(self) -> coredata.OptionsView:
         return self.options
 
     def get_option(self, key: 'OptionKey') -> T.Union[str, int, bool, 'WrapMode']:
diff --git a/mesonbuild/compilers/cuda.py b/mesonbuild/compilers/cuda.py
index 8ed7fa41c..09a7d6af0 100644
--- a/mesonbuild/compilers/cuda.py
+++ b/mesonbuild/compilers/cuda.py
@@ -21,7 +21,7 @@ import typing as T
 from .. import coredata
 from .. import mlog
 from ..mesonlib import (
-    EnvironmentException, Popen_safe, OptionOverrideProxy,
+    EnvironmentException, Popen_safe,
     is_windows, LibType, OptionKey, version_compare,
 )
 from .compilers import (Compiler, cuda_buildtype_args, cuda_optimization_args,
@@ -650,7 +650,7 @@ class CudaCompiler(Compiler):
         host_options = {key: options.get(key, opt) for key, opt in self.host_compiler.get_options().items()}
         std_key = OptionKey('std', machine=self.for_machine, lang=self.host_compiler.language)
         overrides = {std_key: 'none'}
-        return OptionOverrideProxy(overrides, host_options)
+        return coredata.OptionsView(host_options, overrides=overrides)
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
         args = self.get_ccbin_args(options)
diff --git a/mesonbuild/coredata.py b/mesonbuild/coredata.py
index 4b0f9af58..f151c7b81 100644
--- a/mesonbuild/coredata.py
+++ b/mesonbuild/coredata.py
@@ -19,7 +19,9 @@ import pickle, os, uuid
 import sys
 from itertools import chain
 from pathlib import PurePath
-from collections import OrderedDict
+from collections import OrderedDict, abc
+from dataclasses import dataclass
+
 from .mesonlib import (
     HoldableObject,
     MesonException, EnvironmentException, MachineChoice, PerMachine,
@@ -42,12 +44,12 @@ if T.TYPE_CHECKING:
     from .compilers.compilers import Compiler, CompileResult, RunResult, CompileCheckMode
     from .dependencies.detect import TV_DepID
     from .environment import Environment
-    from .mesonlib import OptionOverrideProxy, FileOrString
+    from .mesonlib import FileOrString
     from .cmake.traceparser import CMakeCacheEntry
 
-    OptionDictType = T.Union[T.Dict[str, 'UserOption[T.Any]'], OptionOverrideProxy]
+    OptionDictType = T.Union[T.Dict[str, 'UserOption[T.Any]'], 'OptionsView']
     MutableKeyedOptionDictType = T.Dict['OptionKey', 'UserOption[T.Any]']
-    KeyedOptionDictType = T.Union[MutableKeyedOptionDictType, OptionOverrideProxy]
+    KeyedOptionDictType = T.Union[MutableKeyedOptionDictType, 'OptionsView']
     CompilerCheckCacheKey = T.Tuple[T.Tuple[str, ...], str, FileOrString, T.Tuple[str, ...], CompileCheckMode]
     # code, args
     RunCheckCacheKey = T.Tuple[str, T.Tuple[str, ...]]
@@ -375,6 +377,42 @@ class UserStdOption(UserComboOption):
         raise MesonException(f'None of values {candidates} are supported by the {self.lang.upper()} compiler. ' +
                              f'Possible values are {self.choices}')
 
+@dataclass
+class OptionsView(abc.Mapping):
+    '''A view on an options dictionary for a given subproject and with overrides.
+    '''
+
+    # TODO: the typing here could be made more explicit using a TypeDict from
+    # python 3.8 or typing_extensions
+    options: KeyedOptionDictType
+    subproject: T.Optional[str] = None
+    overrides: T.Optional[T.Mapping[OptionKey, T.Union[str, int, bool, T.List[str]]]] = None
+
+    def __getitem__(self, key: OptionKey) -> UserOption:
+        # FIXME: This is fundamentally the same algorithm than interpreter.get_option_internal().
+        # We should try to share the code somehow.
+        key = key.evolve(subproject=self.subproject)
+        if not key.is_project():
+            opt = self.options.get(key)
+            if opt is None or opt.yielding:
+                opt = self.options[key.as_root()]
+        else:
+            opt = self.options[key]
+            if opt.yielding:
+                opt = self.options.get(key.as_root(), opt)
+        if self.overrides:
+            override_value = self.overrides.get(key.as_root())
+            if override_value is not None:
+                opt = copy.copy(opt)
+                opt.set_value(override_value)
+        return opt
+
+    def __iter__(self) -> T.Iterator[OptionKey]:
+        return iter(self.options)
+
+    def __len__(self) -> int:
+        return len(self.options)
+
 class DependencyCacheType(enum.Enum):
 
     OTHER = 0
diff --git a/mesonbuild/utils/universal.py b/mesonbuild/utils/universal.py
index d44ec03a8..7f0f3852a 100644
--- a/mesonbuild/utils/universal.py
+++ b/mesonbuild/utils/universal.py
@@ -29,7 +29,6 @@ from itertools import tee
 from tempfile import TemporaryDirectory, NamedTemporaryFile
 import typing as T
 import textwrap
-import copy
 import pickle
 import errno
 import json
@@ -42,7 +41,7 @@ if T.TYPE_CHECKING:
 
     from .._typing import ImmutableListProtocol
     from ..build import ConfigurationData
-    from ..coredata import KeyedOptionDictType, UserOption, StrOrBytesPath
+    from ..coredata import StrOrBytesPath
     from ..environment import Environment
     from ..compilers.compilers import Compiler
     from ..interpreterbase.baseobjects import SubProject
@@ -79,7 +78,6 @@ __all__ = [
     'GitException',
     'OptionKey',
     'dump_conf_header',
-    'OptionOverrideProxy',
     'OptionType',
     'OrderedSet',
     'PerMachine',
@@ -2124,52 +2122,6 @@ def generate_list(func: T.Callable[..., T.Generator[_T, None, None]]) -> T.Calla
     return wrapper
 
 
-class OptionOverrideProxy(collections.abc.Mapping):
-    '''Mimic an option list but transparently override selected option
-    values.
-    '''
-
-    # TODO: the typing here could be made more explicit using a TypeDict from
-    # python 3.8 or typing_extensions
-
-    def __init__(self, overrides: T.Dict['OptionKey', T.Any], options: 'KeyedOptionDictType',
-                 subproject: T.Optional[str] = None):
-        self.overrides = overrides
-        self.options = options
-        self.subproject = subproject
-
-    def __getitem__(self, key: 'OptionKey') -> 'UserOption':
-        # FIXME: This is fundamentally the same algorithm than interpreter.get_option_internal().
-        # We should try to share the code somehow.
-        key = key.evolve(subproject=self.subproject)
-        if not key.is_project():
-            opt = self.options.get(key)
-            if opt is None or opt.yielding:
-                opt = self.options[key.as_root()]
-        else:
-            opt = self.options[key]
-            if opt.yielding:
-                opt = self.options.get(key.as_root(), opt)
-        override_value = self.overrides.get(key.as_root())
-        if override_value is not None:
-            opt = copy.copy(opt)
-            opt.set_value(override_value)
-        return opt
-
-    def __iter__(self) -> T.Iterator['OptionKey']:
-        return iter(self.options)
-
-    def __len__(self) -> int:
-        return len(self.options)
-
-    def __eq__(self, other: object) -> bool:
-        if not isinstance(other, OptionOverrideProxy):
-            return NotImplemented
-        t1 = (self.overrides, self.subproject, self.options)
-        t2 = (other.overrides, other.subproject, other.options)
-        return t1 == t2
-
-
 class OptionType(enum.IntEnum):
 
     """Enum used to specify what kind of argument a thing is."""