dependencies: Remove version from cache key

We cannot have 2 different versions with all other kwargs being
identical. This simplifies a lot that code.

mesonbuild/dependencies/base.py

@@ -1984,17 +1984,14 @@ class ExtraFrameworkDependency(ExternalDependency):
 
 
 def get_dep_identifier(name, kwargs, want_cross):
-    # Need immutable objects since the identifier will be used as a dict key
-    version_reqs = listify(kwargs.get('version', []))
-    if isinstance(version_reqs, list):
-        version_reqs = frozenset(version_reqs)
-    identifier = (name, version_reqs, want_cross)
+    identifier = (name, want_cross)
     for key, value in kwargs.items():
-        # 'version' is embedded above as the second element for easy access
+        # 'version' is irrelevant for caching; the caller must check version matches
         # 'native' is handled above with `want_cross`
         # 'required' is irrelevant for caching; the caller handles it separately
         # 'fallback' subprojects cannot be cached -- they must be initialized
-        if key in ('version', 'native', 'required', 'fallback',):
+        # 'default_options' is only used in fallback case
+        if key in ('version', 'native', 'required', 'fallback', 'default_options'):
             continue
         # All keyword arguments are strings, ints, or lists (or lists of lists)
         if isinstance(value, list):

mesonbuild/interpreter.py

@@ -2851,28 +2851,24 @@ external dependencies (including libraries) must go to "dependencies".''')
             want_cross = not kwargs['native']
         else:
             want_cross = is_cross
+
         identifier = dependencies.get_dep_identifier(name, kwargs, want_cross)
-        cached_dep = None
-        # Check if we've already searched for and found this dep
-        if identifier in self.coredata.deps:
-            cached_dep = self.coredata.deps[identifier]
-            mlog.log('Dependency', mlog.bold(name),
-                     'found:', mlog.green('YES'), '(cached)')
-        else:
-            # Check if exactly the same dep with different version requirements
-            # was found already.
-            wanted = identifier[1]
-            for trial, trial_dep in self.coredata.deps.items():
-                # trial[1], identifier[1] are the version requirements
-                if trial[0] != identifier[0] or trial[2:] != identifier[2:]:
-                    continue
-                found = trial_dep.get_version()
-                if not wanted or mesonlib.version_compare_many(found, wanted)[0]:
-                    # We either don't care about the version, or our
-                    # version requirements matched the trial dep's version.
-                    cached_dep = trial_dep
-                    break
-        return identifier, cached_dep
+        cached_dep = self.coredata.deps.get(identifier)
+        if cached_dep:
+            if not cached_dep.found():
+                mlog.log('Dependency', mlog.bold(name),
+                         'found:', mlog.red('NO'), '(cached)')
+                return identifier, cached_dep
+
+            # Verify the cached dep version match
+            wanted = kwargs.get('version', [])
+            found = cached_dep.get_version()
+            if not wanted or mesonlib.version_compare_many(found, wanted)[0]:
+                mlog.log('Dependency', mlog.bold(name),
+                         'found:', mlog.green('YES'), '(cached)')
+                return identifier, cached_dep
+
+        return identifier, None
 
     @staticmethod
     def check_subproject_version(wanted, found):