Clean DefaultOpEnvironment.resolveOpDependencies

gselzer · gselzer · commit 397aa0b99808 · 2024-03-19T16:45:11.000-05:00
diff --git a/scijava-ops-engine/src/main/java/org/scijava/ops/engine/impl/DefaultOpEnvironment.java b/scijava-ops-engine/src/main/java/org/scijava/ops/engine/impl/DefaultOpEnvironment.java
@@ -51,6 +51,7 @@
 import org.scijava.struct.FunctionalMethodType;
 import org.scijava.struct.ItemIO;
 import org.scijava.types.*;
+import org.scijava.types.inference.GenericAssignability;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -595,27 +596,16 @@ private List<RichOp<?>> resolveOpDependencies(OpInfo info,
 			final OpRequest request = inferOpRequest(dependency,
 				dependencyTypeVarAssigns);
 			try {
+				// match Op
 				var depHints = baseDepHints.plus(dependency.hints());
-
-				MatchingConditions conditions = MatchingConditions.from(request,
-					depHints);
-				// see if the request has been matched already
-//				OpInstance<?> cachedOp = getInstance(conditions);
-//				if (cachedOp != null) return conditions;
-
-				// obtain suitable OpCandidate
-				// FIXME: Check cache
-				var candidate = findOpCandidate(request, depHints);
-				var instance = instantiateOp(candidate, depHints);
-
-				// cache instance
-				setInstance(conditions, instance);
-
-				for (var entry : candidate.typeVarAssigns().entrySet()) {
-					dependencyTypeVarAssigns.putIfAbsent(entry.getKey(), entry
-						.getValue());
-				}
+				var conditions = MatchingConditions.from(request, depHints);
+				OpInstance<?> instance = generateCacheHit(conditions);
+				// add Op to dependencies
 				dependencyChains.add(wrapOp(instance, conditions));
+				// refine current type variable knowledge
+				GenericAssignability //
+					.inferTypeVariables(request.getType(), instance.getType()) //
+					.forEach(dependencyTypeVarAssigns::putIfAbsent);
 
 			}
 			catch (final OpMatchingException e) {
diff --git a/scijava-types/src/main/java/org/scijava/types/inference/GenericAssignability.java b/scijava-types/src/main/java/org/scijava/types/inference/GenericAssignability.java
@@ -242,6 +242,25 @@ public static Class<?> getClass(final Object obj) {
 		return obj.getClass();
 	}
 
+	/**
+	 * Tries to infer type vars contained in types from corresponding types from
+	 * inferFrom, putting them into the specified map. <b>When a
+	 * {@link TypeInferenceException} is thrown, the caller should assume that
+	 * some of the mappings within {@code typeMappings} are incorrect.</b>
+	 *
+	 * @param type
+	 * @param inferFrom
+	 * @return the mapping of {@link TypeVariable}s in {@code type} to
+	 *         {@link Type}s in {@code inferFrom}
+	 */
+	public static Map<TypeVariable<?>, Type> inferTypeVariables(Type type,
+		Type inferFrom)
+	{
+		Map<TypeVariable<?>, Type> map = new HashMap<>();
+		inferTypeVariables(new Type[] { type }, new Type[] { inferFrom }, map);
+		return map;
+	}
+
 	/**
 	 * Tries to infer type vars contained in types from corresponding types from
 	 * inferFrom, putting them into the specified map. <b>When a
@@ -457,6 +476,11 @@ else throw new TypeInferenceException(inferFrom +
 	private static void inferTypeVariables(ParameterizedType type, Type inferFrom,
 		Map<TypeVariable<?>, TypeMapping> typeMappings)
 	{
+		// Nothing to infer here...
+		if (type.equals(inferFrom)) {
+			return;
+		}
+
 		if (inferFrom instanceof WildcardType) {
 			inferFrom = getInferrableBound((WildcardType) inferFrom);
 		}
