Support multiple inheritance of rank profiles

17 files changed, 336 insertions, 296 deletions

diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/ApplicationBuilder.java b/config-model/src/main/java/com/yahoo/searchdefinition/ApplicationBuilder.java
index ac4ac649a28..98c6897dbb7 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/ApplicationBuilder.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/ApplicationBuilder.java
@@ -223,9 +223,6 @@ public class ApplicationBuilder {
     private void addRankProfileFiles(Schema schema, String schemaPath) {
         if (applicationPackage == null || schemaPath == null) return;
         Path rankProfilePath = Path.fromString(schemaPath).append(schema.getName());
-        System.out.println("Adding external rank profiles for " + schema + ": Have " +
-                           applicationPackage.getFiles(rankProfilePath, ".profile").size() +
-                           " files in " + rankProfilePath);
         for (NamedReader reader : applicationPackage.getFiles(rankProfilePath, ".profile")) {
             parseRankProfile(reader, schema);
         }
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/DefaultRankProfile.java b/config-model/src/main/java/com/yahoo/searchdefinition/DefaultRankProfile.java
index 4444636fbe8..94d2dfc3cc3 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/DefaultRankProfile.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/DefaultRankProfile.java
@@ -4,52 +4,51 @@ package com.yahoo.searchdefinition;
 import com.yahoo.searchdefinition.document.ImmutableSDField;
 
 import java.util.LinkedHashSet;
+import java.util.List;
 import java.util.Set;
 
 /**
  * The rank profile containing default settings. This is derived from the fields
  * whenever this is accessed.
  *
- * @author  bratseth
+ * @author bratseth
  */
 public class DefaultRankProfile extends RankProfile {
 
     /**
      * Creates a new rank profile
      *
-     * @param rankProfileRegistry The {@link com.yahoo.searchdefinition.RankProfileRegistry} to use for storing and looking up rank profiles.
+     * @param rankProfileRegistry the {@link com.yahoo.searchdefinition.RankProfileRegistry}
+     *                            to use for storing and looking up rank profiles
      */
     public DefaultRankProfile(Schema schema, RankProfileRegistry rankProfileRegistry, RankingConstants rankingConstants) {
         super("default", schema, rankProfileRegistry, rankingConstants);
     }
 
-    /**
-     * Does nothing, the default rank profile can not inherit anything
-     */
-    // TODO: Why not? If that's the case, then fail attempts at it
-    public void setInherited(String inheritedName) {
-    }
+    /** Does nothing, the default rank profile can not inherit anything. */
+    // TODO: Why not? If that's the case, then fail attempts at i
+    @Override
+    public void inherit(String inheritedName) {}
 
-    /** Returns null, the default rank profile can not inherit anything */
-    public String getInheritedName() {
-        return null;
-    }
+    /** Returns empty, the default rank profile can not inherit anything */
+    @Override
+    public List<String> inheritedNames() { return List.of(); }
 
-    /** Returns the rank boost value of the given field */
-    public RankSetting getRankSetting(String fieldOrIndex,RankSetting.Type type) {
-        RankSetting setting = super.getRankSetting(fieldOrIndex,type);
+    @Override
+    public RankSetting getRankSetting(String fieldOrIndex, RankSetting.Type type) {
+        RankSetting setting = super.getRankSetting(fieldOrIndex, type);
         if (setting != null) return setting;
 
         ImmutableSDField field = schema().getConcreteField(fieldOrIndex);
         if (field != null) {
-            setting = toRankSetting(field,type);
+            setting = toRankSetting(field, type);
             if (setting != null)
                 return setting;
         }
 
         Index index = schema().getIndex(fieldOrIndex);
         if (index != null) {
-            setting = toRankSetting(index,type);
+            setting = toRankSetting(index, type);
             if (setting != null)
                 return setting;
         }
@@ -57,13 +56,13 @@ public class DefaultRankProfile extends RankProfile {
         return null;
     }
 
-    private RankSetting toRankSetting(ImmutableSDField field,RankSetting.Type type) {
-        if (type.equals(RankSetting.Type.WEIGHT) && field.getWeight()>0 && field.getWeight()!=100)
-            return new RankSetting(field.getName(),type,field.getWeight());
+    private RankSetting toRankSetting(ImmutableSDField field, RankSetting.Type type) {
+        if (type.equals(RankSetting.Type.WEIGHT) && field.getWeight() > 0 && field.getWeight() != 100)
+            return new RankSetting(field.getName(), type, field.getWeight());
         if (type.equals(RankSetting.Type.RANKTYPE))
-            return new RankSetting(field.getName(),type,field.getRankType());
-        if (type.equals(RankSetting.Type.LITERALBOOST) && field.getLiteralBoost()>0)
-            return new RankSetting(field.getName(),type,field.getLiteralBoost());
+            return new RankSetting(field.getName(), type, field.getRankType());
+        if (type.equals(RankSetting.Type.LITERALBOOST) && field.getLiteralBoost() > 0)
+            return new RankSetting(field.getName(), type, field.getLiteralBoost());
 
         // Index level setting really
         if (type.equals(RankSetting.Type.PREFERBITVECTOR) && field.getRanking().isFilter()) {
@@ -86,6 +85,7 @@ public class DefaultRankProfile extends RankProfile {
      * Returns the names of the fields which have a rank boost setting
      * explicitly in this profile or in fields
      */
+    @Override
     public Set<RankSetting> rankSettings() {
         Set<RankSetting> settings = new LinkedHashSet<>(20);
         settings.addAll(this.rankSettings);
@@ -96,7 +96,7 @@ public class DefaultRankProfile extends RankProfile {
             addSetting(field, RankSetting.Type.PREFERBITVECTOR, settings);
         }
 
-        // Foer settings that really pertains to indexes do the explicit indexes too
+        // For settings that really pertains to indexes do the explicit indexes too
         for (Index index : schema().getExplicitIndices()) {
             addSetting(index, RankSetting.Type.PREFERBITVECTOR, settings);
         }
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/OnnxModel.java b/config-model/src/main/java/com/yahoo/searchdefinition/OnnxModel.java
index d40fe975721..4b849af9662 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/OnnxModel.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/OnnxModel.java
@@ -18,8 +18,8 @@ import java.util.Optional;
 public class OnnxModel extends DistributableResource {
 
     private OnnxModelInfo modelInfo = null;
-    private Map<String, String> inputMap = new HashMap<>();
-    private Map<String, String> outputMap = new HashMap<>();
+    private final Map<String, String> inputMap = new HashMap<>();
+    private final Map<String, String> outputMap = new HashMap<>();
 
     private String  statelessExecutionMode = null;
     private Integer statelessInterOpThreads = null;
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/RankProfile.java b/config-model/src/main/java/com/yahoo/searchdefinition/RankProfile.java
index 1b6c4aa9459..53e9cfd5601 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/RankProfile.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/RankProfile.java
@@ -43,6 +43,7 @@ import java.util.Objects;
 import java.util.Optional;
 import java.util.OptionalDouble;
 import java.util.Set;
+import java.util.function.Predicate;
 import java.util.function.Supplier;
 import java.util.logging.Level;
 import java.util.stream.Collectors;
@@ -65,8 +66,9 @@ public class RankProfile implements Cloneable {
     private final ImmutableSchema schema;
 
     /** The name of the rank profile inherited by this */
-    private String inheritedName = null;
-    private RankProfile inherited = null;
+    private final List<String> inheritedNames = new ArrayList<>();
+    /** Stores the resolved inherited profiles, or null when not resolved. */
+    private List<RankProfile> inherited;
 
     /** The match settings of this profile */
     private MatchPhaseSettings matchPhaseSettings = null;
@@ -96,10 +98,10 @@ public class RankProfile implements Cloneable {
     private double rankScoreDropLimit = -Double.MAX_VALUE;
 
     private Set<ReferenceNode> summaryFeatures;
-    private String inheritedSummaryFeatures;
+    private String inheritedSummaryFeaturesProfileName;
 
     private Set<ReferenceNode> matchFeatures;
-    private String inheritedMatchFeatures;
+    private String inheritedMatchFeaturesProfileName;
 
     private Set<ReferenceNode> rankFeatures;
 
@@ -199,31 +201,28 @@ public class RankProfile implements Cloneable {
     }
 
     /**
-     * Sets the name of the rank profile this inherits. Both rank profiles must be present in the same search
-     * definition
+     * Adds a profile to those inherited by this.
+     * The profile must belong to this schema (directly or by inheritance).
      */
-    public void setInherited(String inheritedName) {
-        this.inheritedName = inheritedName;
-    }
-
-    /** Returns the name of the profile this one inherits, or null if none is inherited */
-    public String getInheritedName() { return inheritedName; }
-
-    /** Returns the inherited rank profile, or null if there is none */
-    private RankProfile getInherited() {
-        if (inheritedName == null) return null;
-        if (inherited == null) {
-            inherited = resolveInherited();
-            if (inherited == null) {
-                String msg = "rank-profile '" + name() + "' inherits '" + inheritedName +
-                             "', but this is not found in " +
-                             ((schema() != null) ? schema() : " global rank profiles");
-                throw new IllegalArgumentException(msg);
-            } else {
-                List<String> children = new ArrayList<>();
-                children.add(createFullyQualifiedName());
-                verifyNoInheritanceCycle(children, inherited);
-            }
+    public void inherit(String inheritedName) {
+        inheritedNames.add(inheritedName);
+    }
+
+    /** Returns the names of the profiles this inherits, if any. */
+    public List<String> inheritedNames() { return inheritedNames; }
+
+    /** Returns the rank profiles inherited by this. */
+    private List<RankProfile> inherited() {
+        if (inheritedNames.isEmpty()) return List.of();
+        if (inherited != null) return inherited;
+
+        for (String inheritedName : inheritedNames) {
+            inherited = (schema() != null) ? resolveInheritedProfiles(schema)
+                                           : List.of(rankProfileRegistry.getGlobal(inheritedName));
+
+            List<String> children = new ArrayList<>();
+            children.add(createFullyQualifiedName());
+            inherited.forEach(profile -> verifyNoInheritanceCycle(children, profile));
         }
         return inherited;
     }
@@ -237,15 +236,26 @@ public class RankProfile implements Cloneable {
     private void verifyNoInheritanceCycle(List<String> children, RankProfile parent) {
         children.add(parent.createFullyQualifiedName());
         String root = children.get(0);
-        if (root.equals(parent.createFullyQualifiedName())) {
+        if (root.equals(parent.createFullyQualifiedName()))
             throw new IllegalArgumentException("There is a cycle in the inheritance for rank-profile '" + root + "' = " + children);
+        for (RankProfile parentInherited : parent.inherited())
+            verifyNoInheritanceCycle(children, parentInherited);
+    }
+
+    private List<RankProfile> resolveInheritedProfiles(ImmutableSchema schema) {
+        List<RankProfile> inherited = new ArrayList<>();
+        for (String inheritedName : inheritedNames) {
+            RankProfile inheritedProfile = resolveInheritedProfile(schema, inheritedName);
+            if (inheritedProfile == null)
+                throw new IllegalArgumentException("rank-profile '" + name() + "' inherits '" + inheritedName +
+                                                   "', but this is not found in " +
+                                                   ((schema() != null) ? schema() : " global rank profiles"));
+            inherited.add(inheritedProfile);
         }
-        if (parent.getInherited() != null) {
-            verifyNoInheritanceCycle(children, parent.getInherited());
-        }
+        return inherited;
     }
 
-    private RankProfile resolveInherited(ImmutableSchema schema) {
+    private RankProfile resolveInheritedProfile(ImmutableSchema schema, String inheritedName) {
         SDDocumentType documentType = schema.getDocument();
         if (documentType != null) {
             if (name.equals(inheritedName)) {
@@ -260,25 +270,11 @@ public class RankProfile implements Cloneable {
         return rankProfileRegistry.get(schema.getName(), inheritedName);
     }
 
-    private RankProfile resolveInherited() {
-        if (inheritedName == null) return null;
-        return (schema() != null)
-                ? resolveInherited(schema)
-                : rankProfileRegistry.getGlobal(inheritedName);
-    }
-
-    /**
-     * Returns whether this profile inherits (directly or indirectly) the given profile
-     *
-     * @param name the profile name to compare this to.
-     * @return whether or not this inherits from the named profile.
-     */
+    /** Returns whether this profile inherits (directly or indirectly) the given profile name. */
     public boolean inherits(String name) {
-        RankProfile parent = getInherited();
-        while (parent != null) {
-            if (parent.name().equals(name))
-                return true;
-            parent = parent.getInherited();
+        for (RankProfile inheritedProfile : inherited()) {
+            if (inheritedProfile.name().equals(name)) return true;
+            if (inheritedProfile.inherits(name)) return true;
         }
         return false;
     }
@@ -289,10 +285,20 @@ public class RankProfile implements Cloneable {
     }
 
     public MatchPhaseSettings getMatchPhaseSettings() {
-        MatchPhaseSettings settings = this.matchPhaseSettings;
-        if (settings != null) return settings;
-        if (getInherited() != null) return getInherited().getMatchPhaseSettings();
-        return null;
+        if (matchPhaseSettings != null) return matchPhaseSettings;
+        return inheritedWith(p -> p.getMatchPhaseSettings() != null,"match phase settings")
+                .map(p -> p.getMatchPhaseSettings()).orElse(null);
+    }
+
+    /** Returns the single profile having the property checked by the given filter, or empty if none */
+    private Optional<RankProfile> inheritedWith(Predicate<RankProfile> property, String propertyDescription) {
+        List<RankProfile> matchingInherited =
+                inherited().stream().filter(profile -> property.test(profile)).collect(Collectors.toList());
+        if (matchingInherited.isEmpty()) return Optional.empty();
+        if (matchingInherited.size() == 1) return Optional.of(matchingInherited.get(0));
+        throw new IllegalArgumentException("Only one of the profiles inherited by " + this + " can contain " +
+                                           propertyDescription + ", but it is present in all of " + matchingInherited);
+
     }
 
     public void addRankSetting(RankSetting rankSetting) {
@@ -306,15 +312,14 @@ public class RankProfile implements Cloneable {
     /**
      * Returns the a rank setting of a field, or null if there is no such rank setting in this profile
      *
-     * @param field the field whose settings to return.
-     * @param type  the type that the field is required to be.
-     * @return the rank setting found, or null.
+     * @param field the field whose settings to return
+     * @param type  the type that the field is required to be
+     * @return the rank setting found, or null
      */
     RankSetting getDeclaredRankSetting(String field, RankSetting.Type type) {
         for (Iterator<RankSetting> i = declaredRankSettingIterator(); i.hasNext(); ) {
             RankSetting setting = i.next();
-            if (setting.getFieldName().equals(field) &&
-                setting.getType().equals(type)) {
+            if (setting.getFieldName().equals(field) && setting.getType() == type) {
                 return setting;
             }
         }
@@ -333,9 +338,8 @@ public class RankProfile implements Cloneable {
         RankSetting rankSetting = getDeclaredRankSetting(field, type);
         if (rankSetting != null) return rankSetting;
 
-        if (getInherited() != null) return getInherited().getRankSetting(field, type);
-
-        return null;
+        return inheritedWith(p -> p.getRankSetting(field, type) != null, "rank setting " + type + " on " + field)
+                .map(p -> p.getRankSetting(field, type)).orElse(null);
     }
 
     /**
@@ -361,12 +365,20 @@ public class RankProfile implements Cloneable {
      * Changes to the returned set will not be reflected in this rank profile.
      */
     public Set<RankSetting> rankSettings() {
-        Set<RankSetting> allSettings = new LinkedHashSet<>(rankSettings);
-        RankProfile parent = getInherited();
-        if (parent != null)
-            allSettings.addAll(parent.rankSettings());
+        Set<RankSetting> settings = new LinkedHashSet<>();
+        for (RankProfile inheritedProfile : inherited()) {
+            for (RankSetting setting : inheritedProfile.rankSettings()) {
+                if (settings.contains(setting))
+                    throw new IllegalArgumentException(setting + " is present in " + inheritedProfile + " inherited by " +
+                                                       this + ", but is also present in another profile inherited by it");
+                settings.add(setting);
+            }
+        }
 
-        return allSettings;
+        // TODO: Here we do things in the wrong order to not break tests. Reverse this.
+        Set<RankSetting> finalSettings = new LinkedHashSet<>(rankSettings);
+        finalSettings.addAll(settings);
+        return finalSettings;
     }
 
     public void addConstant(String name, Value value) {
@@ -385,14 +397,20 @@ public class RankProfile implements Cloneable {
 
     /** Returns an unmodifiable view of the constants available in this */
     public Map<String, Value> getConstants() {
-        if (constants.isEmpty())
-            return getInherited() != null ? getInherited().getConstants() : Collections.emptyMap();
-        if (getInherited() == null || getInherited().getConstants().isEmpty())
-            return Collections.unmodifiableMap(constants);
-
-        Map<String, Value> combinedConstants = new HashMap<>(getInherited().getConstants());
-        combinedConstants.putAll(constants);
-        return combinedConstants;
+        if (inherited().isEmpty()) return new HashMap<>(constants);
+
+        Map<String, Value> allConstants = new HashMap<>();
+        for (var inheritedProfile : inherited()) {
+            for (var constant : inheritedProfile.getConstants().entrySet()) {
+                if (allConstants.containsKey(constant.getKey()))
+                    throw new IllegalArgumentException("Constant '" + constant.getKey() + "' is present in " +
+                                                       inheritedProfile + " inherited by " +
+                                                       this + ", but is also present in another profile inherited by it");
+                allConstants.put(constant.getKey(), constant.getValue());
+            }
+        }
+        allConstants.putAll(constants);
+        return allConstants;
     }
 
     public void addAttributeType(String attributeName, String attributeType) {
@@ -423,9 +441,8 @@ public class RankProfile implements Cloneable {
 
     public RankingExpressionFunction getFirstPhase() {
         if (firstPhaseRanking != null) return firstPhaseRanking;
-        RankProfile inherited = getInherited();
-        if (inherited != null) return inherited.getFirstPhase();
-        return null;
+        return inheritedWith(p -> p.getFirstPhase() != null, "first-phase expression")
+                       .map(p -> p.getFirstPhase()).orElse(null);
     }
 
     void setFirstPhaseRanking(RankingExpression rankingExpression) {
@@ -452,9 +469,8 @@ public class RankProfile implements Cloneable {
 
     public RankingExpressionFunction getSecondPhase() {
         if (secondPhaseRanking != null) return secondPhaseRanking;
-        RankProfile inherited = getInherited();
-        if (inherited != null) return inherited.getSecondPhase();
-        return null;
+        return inheritedWith(p -> p.getSecondPhase() != null, "second-phase expression")
+                .map(p -> p.getSecondPhase()).orElse(null);
     }
 
     public void setSecondPhaseRanking(String expression) {
@@ -466,75 +482,80 @@ public class RankProfile implements Cloneable {
         }
     }
 
-    /** Returns a read-only view of the summary features to use in this profile. This is never null */
-    public Set<ReferenceNode> getSummaryFeatures() {
-        if (inheritedSummaryFeatures != null && summaryFeatures != null) {
-            Set<ReferenceNode> combined = new HashSet<>();
-            combined.addAll(getInherited().getSummaryFeatures());
-            combined.addAll(summaryFeatures);
-            return Collections.unmodifiableSet(combined);
-        }
-        if (summaryFeatures != null) return Collections.unmodifiableSet(summaryFeatures);
-        if (getInherited() != null) return getInherited().getSummaryFeatures();
-        return Set.of();
-    }
-
-    private void addSummaryFeature(ReferenceNode feature) {
-        if (summaryFeatures == null)
-            summaryFeatures = new LinkedHashSet<>();
-        summaryFeatures.add(feature);
-    }
-
-    /** Adds the content of the given feature list to the internal list of summary features. */
-    public void addSummaryFeatures(FeatureList features) {
-        for (ReferenceNode feature : features) {
-            addSummaryFeature(feature);
-        }
-    }
+    // TODO: Below we have duplicate methods for summary and match features: Encapsulate this in a single parametrized
+    //       class instead (and probably make rank features work the same).
 
     /**
      * Sets the name this should inherit the summary features of.
-     * Without setting this, this will either have the summary features of the parent,
+     * Without setting this, this will either have the summary features of the single parent setting them,
      * or if summary features are set in this, only have the summary features in this.
      * With this set the resulting summary features of this will be the superset of those defined in this and
      * the final (with inheritance included) summary features of the given parent.
-     * The profile must be the profile which is directly inherited by this.
-     *
+     * The profile must be one which is directly inherited by this.
      */
     public void setInheritedSummaryFeatures(String parentProfile) {
-        if ( ! parentProfile.equals(inheritedName))
-            throw new IllegalArgumentException("This can only inherit the summary features of its parent, '" +
-                                               inheritedName + ", but attempting to inherit '" + parentProfile);
-        this.inheritedSummaryFeatures = parentProfile;
+        if ( ! inheritedNames().contains(parentProfile))
+            throw new IllegalArgumentException("This can only inherit the summary features of a directly inherited profile, '" +
+                                               ", but attempting to inherit '" + parentProfile);
+        this.inheritedSummaryFeaturesProfileName = parentProfile;
     }
 
     /**
      * Sets the name of a profile this should inherit the match features of.
-     * Without setting this, this will either have the match features of the parent,
+     * Without setting this, this will either have the match features of the single parent setting them,
      * or if match features are set in this, only have the match features in this.
      * With this set the resulting match features of this will be the superset of those defined in this and
      * the final (with inheritance included) match features of the given parent.
-     * The profile must be the profile which is directly inherited by this.
+     * The profile must be one which which is directly inherited by this.
      *
      */
     public void setInheritedMatchFeatures(String parentProfile) {
-        if ( ! parentProfile.equals(inheritedName))
-            throw new IllegalArgumentException("This rank profile ("+name+") can only inherit the match features of its parent, '" +
-                                               inheritedName + ", but attemtping to inherit '" + parentProfile);
-        this.inheritedMatchFeatures = parentProfile;
+        if ( ! inheritedNames().contains(parentProfile))
+            throw new IllegalArgumentException("This can only inherit the match features of a directly inherited profile, '" +
+                                               ", but attempting to inherit '" + parentProfile);
+        this.inheritedMatchFeaturesProfileName = parentProfile;
+    }
+
+    /** Returns a read-only view of the summary features to use in this profile. This is never null */
+    public Set<ReferenceNode> getSummaryFeatures() {
+        if (inheritedSummaryFeaturesProfileName != null && summaryFeatures != null) {
+            Set<ReferenceNode> combined = new HashSet<>();
+            RankProfile inherited = inherited().stream()
+                                               .filter(p -> p.name().equals(inheritedSummaryFeaturesProfileName))
+                                               .findAny()
+                                               .orElseThrow();
+            combined.addAll(inherited.getSummaryFeatures());
+            combined.addAll(summaryFeatures);
+            return Collections.unmodifiableSet(combined);
+        }
+        if (summaryFeatures != null) return Collections.unmodifiableSet(summaryFeatures);
+        return inheritedWith(p -> ! p.getSummaryFeatures().isEmpty(), "summary features")
+                .map(p -> p.getSummaryFeatures())
+                .orElse(Set.of());
     }
 
     /** Returns a read-only view of the match features to use in this profile. This is never null */
     public Set<ReferenceNode> getMatchFeatures() {
-        if (inheritedMatchFeatures != null && matchFeatures != null) {
+        if (inheritedMatchFeaturesProfileName != null && matchFeatures != null) {
             Set<ReferenceNode> combined = new HashSet<>();
-            combined.addAll(getInherited().getMatchFeatures());
+            RankProfile inherited = inherited().stream()
+                                               .filter(p -> p.name().equals(inheritedMatchFeaturesProfileName))
+                                               .findAny()
+                                               .orElseThrow();
+            combined.addAll(inherited.getMatchFeatures());
             combined.addAll(matchFeatures);
             return Collections.unmodifiableSet(combined);
         }
         if (matchFeatures != null) return Collections.unmodifiableSet(matchFeatures);
-        if (getInherited() != null) return getInherited().getMatchFeatures();
-        return Set.of();
+        return inheritedWith(p -> ! p.getMatchFeatures().isEmpty(), "match features")
+                .map(p -> p.getMatchFeatures())
+                .orElse(Set.of());
+    }
+
+    private void addSummaryFeature(ReferenceNode feature) {
+        if (summaryFeatures == null)
+            summaryFeatures = new LinkedHashSet<>();
+        summaryFeatures.add(feature);
     }
 
     private void addMatchFeature(ReferenceNode feature) {
@@ -543,6 +564,13 @@ public class RankProfile implements Cloneable {
         matchFeatures.add(feature);
     }
 
+    /** Adds the content of the given feature list to the internal list of summary features. */
+    public void addSummaryFeatures(FeatureList features) {
+        for (ReferenceNode feature : features) {
+            addSummaryFeature(feature);
+        }
+    }
+
     /** Adds the content of the given feature list to the internal list of match features. */
     public void addMatchFeatures(FeatureList features) {
         for (ReferenceNode feature : features) {
@@ -553,8 +581,8 @@ public class RankProfile implements Cloneable {
     /** Returns a read-only view of the rank features to use in this profile. This is never null */
     public Set<ReferenceNode> getRankFeatures() {
         if (rankFeatures != null) return Collections.unmodifiableSet(rankFeatures);
-        if (getInherited() != null) return getInherited().getRankFeatures();
-        return Collections.emptySet();
+        return inheritedWith(p -> ! p.getRankFeatures().isEmpty(), "summary-features")
+                .map(p -> p.getRankFeatures()).orElse(Set.of());
     }
 
     private void addRankFeature(ReferenceNode feature) {
@@ -585,12 +613,15 @@ public class RankProfile implements Cloneable {
 
     /** Returns a read only map view of the rank properties to use in this profile. This is never null. */
     public Map<String, List<RankProperty>> getRankPropertyMap() {
-        if (rankProperties.size() == 0 && getInherited() == null) return Collections.emptyMap();
-        if (rankProperties.size() == 0) return getInherited().getRankPropertyMap();
-        if (getInherited() == null) return Collections.unmodifiableMap(rankProperties);
+        if (rankProperties.size() == 0 && inherited().isEmpty()) return Map.of();
+        if (inherited().isEmpty()) return Collections.unmodifiableMap(rankProperties);
+
+        var inheritedProperties = inheritedWith(p -> ! p.getRankPropertyMap().isEmpty(), "rank-properties")
+                .map(p -> p.getRankPropertyMap()).orElse(Map.of());
+        if (rankProperties.isEmpty()) return inheritedProperties;
 
         // Neither is null
-        Map<String, List<RankProperty>> combined = new LinkedHashMap<>(getInherited().getRankPropertyMap());
+        Map<String, List<RankProperty>> combined = new LinkedHashMap<>(inheritedProperties);
         combined.putAll(rankProperties); // Don't combine values across inherited properties
         return Collections.unmodifiableMap(combined);
     }
@@ -604,57 +635,44 @@ public class RankProfile implements Cloneable {
         rankProperties.computeIfAbsent(rankProperty.getName(), (String key) -> new ArrayList<>(1)).add(rankProperty);
     }
 
-    @Override
-    public String toString() {
-        return "rank profile '" + name() + "'";
-    }
+    public void setRerankCount(int rerankCount) { this.rerankCount = rerankCount; }
 
     public int getRerankCount() {
-        return (rerankCount < 0 && (getInherited() != null))
-                ?  getInherited().getRerankCount()
-                : rerankCount;
+        if (rerankCount >= 0) return rerankCount;
+        return inheritedWith(p -> p.getRerankCount() >= 0, "rerank-count")
+                .map(p -> p.getRerankCount()).orElse(-1);
     }
 
+    public void setNumThreadsPerSearch(int numThreads) { this.numThreadsPerSearch = numThreads; }
+
     public int getNumThreadsPerSearch() {
-        return (numThreadsPerSearch < 0 && (getInherited() != null))
-                ?  getInherited().getNumThreadsPerSearch()
-                : numThreadsPerSearch;
+        if (numThreadsPerSearch >= 0) return numThreadsPerSearch;
+        return inheritedWith(p -> p.getNumThreadsPerSearch() >= 0, "num-threads-per-search")
+                .map(p -> p.getNumThreadsPerSearch()).orElse(-1);
     }
 
-    public void setNumThreadsPerSearch(int numThreads) {
-        this.numThreadsPerSearch = numThreads;
-    }
+    public void setMinHitsPerThread(int minHits) { this.minHitsPerThread = minHits; }
 
     public int getMinHitsPerThread() {
-        return (minHitsPerThread < 0 && (getInherited() != null))
-                ?  getInherited().getMinHitsPerThread()
-                : minHitsPerThread;
-    }
-
-    public void setMinHitsPerThread(int minHits) {
-        this.minHitsPerThread = minHits;
+        if (minHitsPerThread >= 0) return minHitsPerThread;
+        return inheritedWith(p -> p.getMinHitsPerThread() >= 0, "min-hits-per-search")
+                .map(p -> p.getMinHitsPerThread()).orElse(-1);
     }
 
-    public void setNumSearchPartitions(int numSearchPartitions) {
-        this.numSearchPartitions = numSearchPartitions;
-    }
+    public void setNumSearchPartitions(int numSearchPartitions) { this.numSearchPartitions = numSearchPartitions; }
 
     public int getNumSearchPartitions() {
-        return (numSearchPartitions < 0 && (getInherited() != null))
-                ?  getInherited().getNumSearchPartitions()
-                : numSearchPartitions;
+        if (numSearchPartitions >= 0) return numSearchPartitions;
+        return inheritedWith(p -> p.getNumSearchPartitions() >= 0, "num-search-partitions")
+                .map(p -> p.getNumSearchPartitions()).orElse(-1);
     }
 
-    public OptionalDouble getTermwiseLimit() {
-        return ((termwiseLimit == null) && (getInherited() != null))
-                ?  getInherited().getTermwiseLimit()
-                : (termwiseLimit != null) ? OptionalDouble.of(termwiseLimit) : OptionalDouble.empty();
-    }
     public void setTermwiseLimit(double termwiseLimit) { this.termwiseLimit = termwiseLimit; }
 
-    /** Sets the rerank count. Set to -1 to use inherited */
-    public void setRerankCount(int rerankCount) {
-        this.rerankCount = rerankCount;
+    public OptionalDouble getTermwiseLimit() {
+        if (termwiseLimit != null) return OptionalDouble.of(termwiseLimit);
+        return inheritedWith(p -> p.getTermwiseLimit().isPresent(), "termwise-limit")
+                .map(p -> p.getTermwiseLimit()).orElse(OptionalDouble.empty());
     }
 
     /** Whether we should ignore the default rank features. Set to null to use inherited */
@@ -664,10 +682,26 @@ public class RankProfile implements Cloneable {
 
     public boolean getIgnoreDefaultRankFeatures() {
         if (ignoreDefaultRankFeatures != null) return ignoreDefaultRankFeatures;
-        return (getInherited() != null) && getInherited().getIgnoreDefaultRankFeatures();
+        return inheritedWith(p -> p.ignoreDefaultRankFeatures != null, "ignore-default-rank-features")
+                       .map(p -> p.getIgnoreDefaultRankFeatures()).orElse(false);
+    }
+
+    public void setKeepRankCount(int rerankArraySize) { this.keepRankCount = rerankArraySize; }
+
+    public int getKeepRankCount() {
+        if (keepRankCount >= 0) return keepRankCount;
+        return inheritedWith(p -> p.getKeepRankCount() >= 0, "keep-rank-count")
+                .map(p -> p.getKeepRankCount()).orElse(-1);
+    }
+
+    public void setRankScoreDropLimit(double rankScoreDropLimit) { this.rankScoreDropLimit = rankScoreDropLimit; }
+
+    public double getRankScoreDropLimit() {
+        if (rankScoreDropLimit > -Double.MAX_VALUE) return rankScoreDropLimit;
+        return inheritedWith(p -> p.getRankScoreDropLimit() > -Double.MAX_VALUE, "rank.score-drop-limit")
+                .map(p -> p.getRankScoreDropLimit()).orElse(rankScoreDropLimit);
     }
 
-    /** Adds a function */
     public void addFunction(String name, List<String> arguments, String expression, boolean inline) {
         try {
             addFunction(parseRankingExpression(name, arguments, expression), inline);
@@ -729,10 +763,11 @@ public class RankProfile implements Cloneable {
 
     public RankingExpressionFunction findFunction(String name) {
         RankingExpressionFunction function = functions.get(name);
-        return ((function == null) && (getInherited() != null))
-                ? getInherited().findFunction(name)
-                : function;
+        if (function != null) return function;
+        return inheritedWith(p -> p.findFunction(name) != null, "function '" + name + "'")
+                       .map(p -> p.findFunction(name)).orElse(null);
     }
+
     /** Returns an unmodifiable snapshot of the functions in this */
     public Map<String, RankingExpressionFunction> getFunctions() {
         updateCachedFunctions();
@@ -749,59 +784,42 @@ public class RankProfile implements Cloneable {
     }
 
     private  Map<String, RankingExpressionFunction> gatherAllFunctions() {
-        if (functions.isEmpty() && getInherited() == null) return Collections.emptyMap();
-        if (functions.isEmpty()) return getInherited().getFunctions();
-        if (getInherited() == null) return Collections.unmodifiableMap(new LinkedHashMap<>(functions));
-
-        // Neither is null
-        Map<String, RankingExpressionFunction> allFunctions = new LinkedHashMap<>(getInherited().getFunctions());
+        if (functions.isEmpty() && inherited().isEmpty()) return Map.of();
+        if (inherited().isEmpty()) return Collections.unmodifiableMap(new LinkedHashMap<>(functions));
+
+        // Combine
+        Map<String, RankingExpressionFunction> allFunctions = new LinkedHashMap<>();
+        for (var inheritedProfile : inherited()) {
+            for (var function : inheritedProfile.getFunctions().entrySet()) {
+                if (allFunctions.containsKey(function.getKey()))
+                    throw new IllegalArgumentException(this + " inherits " + inheritedProfile + " which contains " +
+                                                       function.getValue() + ", but this function is already " +
+                                                       "defined in another profile this inherits");
+                allFunctions.put(function.getKey(), function.getValue());
+            }
+        }
         allFunctions.putAll(functions);
         return Collections.unmodifiableMap(allFunctions);
     }
 
     private boolean needToUpdateFunctionCache() {
-        if (getInherited() != null)
-            return (allFunctionsCached == null) || getInherited().needToUpdateFunctionCache();
+        if (inherited().stream().anyMatch(profile -> profile.needToUpdateFunctionCache())) return true;
         return allFunctionsCached == null;
     }
 
-    public int getKeepRankCount() {
-        if (keepRankCount >= 0) return keepRankCount;
-        if (getInherited() != null) return getInherited().getKeepRankCount();
-        return -1;
-    }
-
-    public void setKeepRankCount(int rerankArraySize) {
-        this.keepRankCount = rerankArraySize;
-    }
-
-    public double getRankScoreDropLimit() {
-        if (rankScoreDropLimit >- Double.MAX_VALUE) return rankScoreDropLimit;
-        if (getInherited() != null) return getInherited().getRankScoreDropLimit();
-        return rankScoreDropLimit;
-    }
+    public Set<String> filterFields() { return filterFields; }
 
-    public void setRankScoreDropLimit(double rankScoreDropLimit) {
-        this.rankScoreDropLimit = rankScoreDropLimit;
-    }
+    /** Returns all filter fields in this profile and any profile it inherits. */
+    public Set<String> allFilterFields() {
+        Set<String> inheritedFilterFields =
+                inheritedWith(p -> ! p.allFilterFields().isEmpty(), "filter fields")
+                        .map(p -> p.allFilterFields()).orElse(Set.of());
 
-    public Set<String> filterFields() {
-        return filterFields;
-    }
+        if (inheritedFilterFields.isEmpty()) return Collections.unmodifiableSet(filterFields);
 
-    /**
-     * Returns all filter fields in this profile and any profile it inherits.
-     *
-     * @return the set of all filter fields
-     */
-    public Set<String> allFilterFields() {
-        RankProfile parent = getInherited();
-        Set<String> retval = new LinkedHashSet<>();
-        if (parent != null) {
-            retval.addAll(parent.allFilterFields());
-        }
-        retval.addAll(filterFields());
-        return retval;
+        Set<String> combined = new LinkedHashSet<>(inheritedFilterFields);
+        combined.addAll(filterFields());
+        return combined;
     }
 
     private ExpressionFunction parseRankingExpression(String name, List<String> arguments, String expression) throws ParseException {
@@ -892,7 +910,7 @@ public class RankProfile implements Cloneable {
         secondPhaseRanking = compile(this.getSecondPhase(), queryProfiles, featureTypes, importedModels, getConstants(), inlineFunctions, expressionTransforms);
 
         // Function compiling second pass: compile all functions and insert previously compiled inline functions
-        // TODO This merges all functions from inherited profiles too and erases inheritance information. Not good.
+        // TODO: This merges all functions from inherited profiles too and erases inheritance information. Not good.
         functions = compileFunctions(this::getFunctions, queryProfiles, featureTypes, importedModels, inlineFunctions, expressionTransforms);
         allFunctionsCached = null;
     }
@@ -947,6 +965,7 @@ public class RankProfile implements Cloneable {
                                       Map<String, RankingExpressionFunction> inlineFunctions,
                                       ExpressionTransforms expressionTransforms) {
         if (function == null) return null;
+
         RankProfileTransformContext context = new RankProfileTransformContext(this,
                                                                               queryProfiles,
                                                                               featureTypes,
@@ -1063,6 +1082,11 @@ public class RankProfile implements Cloneable {
         });
     }
 
+    @Override
+    public String toString() {
+        return "rank profile '" + name() + "'";
+    }
+
     /**
      * A rank setting. The identity of a rank setting is its field name and type (not value).
      * A rank setting is immutable.
@@ -1105,8 +1129,9 @@ public class RankProfile implements Cloneable {
                 return name;
             }
 
+            @Override
             public String toString() {
-                return "type: " + name;
+                return "type " + name;
             }
 
         }
@@ -1219,7 +1244,7 @@ public class RankProfile implements Cloneable {
 
         @Override
         public String toString() {
-            return "function " + function;
+            return function.toString();
         }
 
     }
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/derived/FieldRankSettings.java b/config-model/src/main/java/com/yahoo/searchdefinition/derived/FieldRankSettings.java
index c6f59fbe596..2a2950f71e9 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/derived/FieldRankSettings.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/derived/FieldRankSettings.java
@@ -4,11 +4,9 @@ package com.yahoo.searchdefinition.derived;
 import com.yahoo.collections.Pair;
 
 import java.util.ArrayList;
-import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.logging.Logger;
 
 /**
  * The rank settings of a field used for native rank features.
@@ -17,9 +15,7 @@ import java.util.logging.Logger;
  */
 public class FieldRankSettings {
 
-    private static final Logger logger = Logger.getLogger(FieldRankSettings.class.getName());
-
-    private String fieldName;
+    private final String fieldName;
 
     private final Map<String, NativeTable> tables = new LinkedHashMap<>();
 
@@ -30,7 +26,7 @@ public class FieldRankSettings {
     public void addTable(NativeTable table) {
         NativeTable existing = tables.get(table.getType().getName());
         if (existing != null) {
-            logger.info("Using already specified rank table " + existing + " for field " + fieldName + ", not " + table);
+            // TODO: Throw?
             return;
         }
         tables.put(table.getType().getName(), table);
@@ -60,8 +56,7 @@ public class FieldRankSettings {
 
     public List<Pair<String, String>> deriveRankProperties() {
         List<Pair<String, String>> properties = new ArrayList<>();
-        for (Iterator<NativeTable> i = tables.values().iterator(); i.hasNext();) {
-            NativeTable table = i.next();
+        for (NativeTable table : tables.values()) {
             if (isFieldMatchTable(table))
                 properties.add(new Pair<>("nativeFieldMatch." + table.getType().getName() + "." + fieldName, table.getName()));
             if (isAttributeMatchTable(table))
@@ -72,6 +67,7 @@ public class FieldRankSettings {
         return properties;
     }
 
+    @Override
     public String toString() {
         return "rank settings of field " + fieldName;
     }
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/derived/RankProfileList.java b/config-model/src/main/java/com/yahoo/searchdefinition/derived/RankProfileList.java
index 86c1d478974..bcebdf3a916 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/derived/RankProfileList.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/derived/RankProfileList.java
@@ -73,9 +73,9 @@ public class RankProfileList extends Derived implements RankProfilesConfig.Produ
     }
 
     private boolean areDependenciesReady(RankProfile rank, RankProfileRegistry registry) {
-        return (rank.getInheritedName() == null) ||
-                rankProfiles.containsKey(rank.getInheritedName()) ||
-                (rank.schema() != null && registry.resolve(rank.schema().getDocument(), rank.getInheritedName()) != null);
+        return rank.inheritedNames().isEmpty() ||
+               rankProfiles.keySet().containsAll(rank.inheritedNames()) ||
+               (rank.schema() != null && rank.inheritedNames().stream().allMatch(name -> registry.resolve(rank.schema().getDocument(), name) != null));
     }
 
     private void deriveRankProfiles(RankProfileRegistry rankProfileRegistry,
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/derived/RawRankProfile.java b/config-model/src/main/java/com/yahoo/searchdefinition/derived/RawRankProfile.java
index a64f0939677..75703c33f07 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/derived/RawRankProfile.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/derived/RawRankProfile.java
@@ -156,8 +156,7 @@ public class RawRankProfile implements RankProfilesConfig.Producer {
         /**
          * Creates a raw rank profile from the given rank profile
          */
-        Deriver(RankProfile compiled, AttributeFields attributeFields, ModelContext.Properties deployProperties)
-        {
+        Deriver(RankProfile compiled, AttributeFields attributeFields, ModelContext.Properties deployProperties) {
             rankprofileName = compiled.name();
             attributeTypes = compiled.getAttributeTypes();
             queryFeatureTypes = compiled.getQueryFeatureTypes();
@@ -277,14 +276,15 @@ public class RawRankProfile implements RankProfilesConfig.Producer {
         private void deriveRankTypeSetting(RankProfile rankProfile, AttributeFields attributeFields) {
             for (Iterator<RankProfile.RankSetting> i = rankProfile.rankSettingIterator(); i.hasNext(); ) {
                 RankProfile.RankSetting setting = i.next();
-                if (!setting.getType().equals(RankProfile.RankSetting.Type.RANKTYPE)) continue;
+                if (setting.getType() != RankProfile.RankSetting.Type.RANKTYPE) continue;
 
                 deriveNativeRankTypeSetting(setting.getFieldName(), (RankType) setting.getValue(), attributeFields,
-                        hasDefaultRankTypeSetting(rankProfile, setting.getFieldName()));
+                                            hasDefaultRankTypeSetting(rankProfile, setting.getFieldName()));
             }
         }
 
-        private void deriveNativeRankTypeSetting(String fieldName, RankType rankType, AttributeFields attributeFields, boolean isDefaultSetting) {
+        private void deriveNativeRankTypeSetting(String fieldName, RankType rankType, AttributeFields attributeFields,
+                                                 boolean isDefaultSetting) {
             if (isDefaultSetting) return;
 
             NativeRankTypeDefinition definition = nativeRankTypeDefinitions.getRankTypeDefinition(rankType);
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/expressiontransforms/ConstantTensorTransformer.java b/config-model/src/main/java/com/yahoo/searchdefinition/expressiontransforms/ConstantTensorTransformer.java
index 166255799bd..f6ed5abaa7f 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/expressiontransforms/ConstantTensorTransformer.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/expressiontransforms/ConstantTensorTransformer.java
@@ -63,8 +63,8 @@ public class ConstantTensorTransformer extends ExpressionTransformer<RankProfile
 
         TensorValue tensorValue = (TensorValue)value;
         String tensorType = tensorValue.asTensor().type().toString();
-        context.rankProperties().put(constantReference.toString() + ".value", tensorValue.toString());
-        context.rankProperties().put(constantReference.toString() + ".type", tensorType);
+        context.rankProperties().put(constantReference + ".value", tensorValue.toString());
+        context.rankProperties().put(constantReference + ".type", tensorType);
         return new ReferenceNode(constantReference);
     }
 
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/expressiontransforms/OnnxFeatureConverter.java b/config-model/src/main/java/com/yahoo/searchdefinition/expressiontransforms/OnnxFeatureConverter.java
index ae8f918dd4b..6944a1f9dd1 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/expressiontransforms/OnnxFeatureConverter.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/expressiontransforms/OnnxFeatureConverter.java
@@ -39,7 +39,6 @@ public class OnnxFeatureConverter extends ExpressionTransformer<RankProfileTrans
 
     private ExpressionNode transformFeature(ReferenceNode feature, RankProfileTransformContext context) {
         if ( ! feature.getName().equals("onnx_vespa")) return feature;
-
         try {
             FeatureArguments arguments = asFeatureArguments(feature.getArguments());
             ConvertedModel convertedModel =
diff --git a/config-model/src/main/javacc/SDParser.jj b/config-model/src/main/javacc/SDParser.jj
index b4d2af42f55..f4a6ac1b03d 100644
--- a/config-model/src/main/javacc/SDParser.jj
+++ b/config-model/src/main/javacc/SDParser.jj
@@ -2036,15 +2036,15 @@ Object rankProfileItem(RankProfile profile) : { }
 /**
  * This rule consumes an inherits statement of a rank-profile.
  *
- * @param profile The profile to modify.
+ * @param profile the profile to modify
  */
 void inheritsRankProfile(RankProfile profile) :
 {
-    String str;
+    String name;
 }
 {
-    <INHERITS> str = identifierWithDash()
-    { profile.setInherited(str); }
+    <INHERITS> name = identifierWithDash() { profile.inherit(name); }
+    ( <COMMA>  name = identifierWithDash() { profile.inherit(name);; } )*
 }
 
 /**
diff --git a/config-model/src/test/derived/attributerank/attributerank.sd b/config-model/src/test/derived/attributerank/attributerank.sd
index 86f96e4817c..4989e1795cd 100644
--- a/config-model/src/test/derived/attributerank/attributerank.sd
+++ b/config-model/src/test/derived/attributerank/attributerank.sd
@@ -38,4 +38,5 @@ search attributerank {
     rank-type singledouble: identity
     rank-type singlestring: identity
   }
+
 }
diff --git a/config-model/src/test/derived/rankprofilemodularity/rank-profiles.cfg b/config-model/src/test/derived/rankprofilemodularity/rank-profiles.cfg
index 8953a8b6bcf..1c30810e2ef 100644
--- a/config-model/src/test/derived/rankprofilemodularity/rank-profiles.cfg
+++ b/config-model/src/test/derived/rankprofilemodularity/rank-profiles.cfg
@@ -18,6 +18,15 @@ rankprofile[].fef.property[].name "rankingExpression(f2).rankingScript"
 rankprofile[].fef.property[].value "fieldMatch(title) + rankingExpression(fo2)"
 rankprofile[].fef.property[].name "vespa.rank.firstphase"
 rankprofile[].fef.property[].value "rankingExpression(f2)"
+rankprofile[].name "in_schema3"
+rankprofile[].fef.property[].name "rankingExpression(fo2).rankingScript"
+rankprofile[].fef.property[].value "random"
+rankprofile[].fef.property[].name "rankingExpression(f2).rankingScript"
+rankprofile[].fef.property[].value "fieldMatch(title) + rankingExpression(fo2)"
+rankprofile[].fef.property[].name "rankingExpression(fo1).rankingScript"
+rankprofile[].fef.property[].value "now"
+rankprofile[].fef.property[].name "vespa.rank.firstphase"
+rankprofile[].fef.property[].value "rankingExpression(f2)"
 rankprofile[].name "outside_schema1"
 rankprofile[].fef.property[].name "rankingExpression(fo1).rankingScript"
 rankprofile[].fef.property[].value "now"
diff --git a/config-model/src/test/derived/rankprofilemodularity/test.sd b/config-model/src/test/derived/rankprofilemodularity/test.sd
index 720e2143f17..58ee280490e 100644
--- a/config-model/src/test/derived/rankprofilemodularity/test.sd
+++ b/config-model/src/test/derived/rankprofilemodularity/test.sd
@@ -28,4 +28,16 @@ schema test {
 
     }
 
+    rank-profile in_schema3 inherits outside_schema1, outside_schema2 {
+
+        function f2() {
+            expression: fieldMatch(title) + fo2
+        }
+
+        first-phase {
+            expression: f2
+        }
+
+    }
+
 }
\ No newline at end of file
diff --git a/config-model/src/test/java/com/yahoo/searchdefinition/RankProfileTestCase.java b/config-model/src/test/java/com/yahoo/searchdefinition/RankProfileTestCase.java
index c88e8149e46..df64d65aec3 100644
--- a/config-model/src/test/java/com/yahoo/searchdefinition/RankProfileTestCase.java
+++ b/config-model/src/test/java/com/yahoo/searchdefinition/RankProfileTestCase.java
@@ -52,7 +52,7 @@ public class RankProfileTestCase extends AbstractSchemaTestCase {
         document.addField("b", DataType.STRING);
         schema.addDocument(document);
         RankProfile child = new RankProfile("child", schema, rankProfileRegistry, schema.rankingConstants());
-        child.setInherited("default");
+        child.inherit("default");
         rankProfileRegistry.add(child);
 
         Iterator<RankProfile.RankSetting> i = child.rankSettingIterator();
diff --git a/config-model/src/test/java/com/yahoo/searchdefinition/SchemaImporterTestCase.java b/config-model/src/test/java/com/yahoo/searchdefinition/SchemaImporterTestCase.java
index 8a9300a83eb..9c895b452d5 100644
--- a/config-model/src/test/java/com/yahoo/searchdefinition/SchemaImporterTestCase.java
+++ b/config-model/src/test/java/com/yahoo/searchdefinition/SchemaImporterTestCase.java
@@ -18,6 +18,7 @@ import org.junit.Test;
 import java.io.IOException;
 import java.util.Iterator;
 
+import static com.google.common.collect.testing.Helpers.assertEmpty;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
@@ -53,14 +54,14 @@ public class SchemaImporterTestCase extends AbstractSchemaTestCase {
         new MakeAliases(schema, new BaseDeployLogger(), rankProfileRegistry, new QueryProfiles()).process(true, false);
 
         // First field
-        field=(SDField) document.getField("title");
-        assertEquals(DataType.STRING,field.getDataType());
+        field = (SDField) document.getField("title");
+        assertEquals(DataType.STRING, field.getDataType());
         assertEquals("{ input title | tokenize normalize stem:\"BEST\" | summary title | index title; }", field.getIndexingScript().toString());
         assertFalse(schema.getIndex("default").isPrefix());
         assertTrue(schema.getIndex("title").isPrefix());
-        Iterator<String> titleAliases= schema.getIndex("title").aliasIterator();
-        assertEquals("aliaz",titleAliases.next());
-        assertEquals("analias.totitle",titleAliases.next());
+        Iterator<String> titleAliases = schema.getIndex("title").aliasIterator();
+        assertEquals("aliaz", titleAliases.next());
+        assertEquals("analias.totitle", titleAliases.next());
         assertEquals("analias.todefault",
                      schema.getIndex("default").aliasIterator().next());
         assertEquals(RankType.IDENTITY, field.getRankType());
@@ -70,7 +71,7 @@ public class SchemaImporterTestCase extends AbstractSchemaTestCase {
         assertTrue(field.isHeader());
 
         // Second field
-        field=(SDField) document.getField("description");
+        field = (SDField) document.getField("description");
         assertEquals(RankType.ABOUT, field.getRankType());
         assertEquals(SummaryTransform.NONE,
                      field.getSummaryField("description").getTransform());
@@ -81,30 +82,30 @@ public class SchemaImporterTestCase extends AbstractSchemaTestCase {
         assertEquals("hallo", schema.getIndex("description").aliasIterator().next());
 
         // Third field
-        field=(SDField) document.getField("chatter");
+        field = (SDField) document.getField("chatter");
         assertEquals(RankType.ABOUT, field.getRankType());
         assertNull(field.getStemming());
         assertTrue(field.getNormalizing().doRemoveAccents());
 
         // Fourth field
-        field=(SDField) document.getField("category");
+        field = (SDField) document.getField("category");
         assertEquals(0, field.getAttributes().size());
         assertEquals(Stemming.NONE, field.getStemming());
         assertFalse(field.getNormalizing().doRemoveAccents());
 
         // Fifth field
-        field=(SDField) document.getField("popularity");
+        field = (SDField) document.getField("popularity");
         assertEquals("{ input popularity | attribute popularity; }",
                      field.getIndexingScript().toString());
 
         // Sixth field
-        field=(SDField) document.getField("measurement");
-        assertEquals(DataType.INT,field.getDataType());
+        field = (SDField) document.getField("measurement");
+        assertEquals(DataType.INT, field.getDataType());
         assertEquals(RankType.EMPTY, field.getRankType());
         assertEquals(1, field.getAttributes().size());
 
         // Seventh field
-        field= schema.getConcreteField("categories");
+        field = schema.getConcreteField("categories");
         assertEquals("{ input categories_src | lowercase | normalize | tokenize normalize stem:\"BEST\" | index categories; }",
                      field.getIndexingScript().toString());
         assertTrue(field.isHeader());
@@ -139,27 +140,27 @@ public class SchemaImporterTestCase extends AbstractSchemaTestCase {
         assertEquals(Attribute.CollectionType.ARRAY, attribute.getCollectionType());
 
         // Rank Profiles
-        RankProfile profile=rankProfileRegistry.get(schema, "default");
+        RankProfile profile = rankProfileRegistry.get(schema, "default");
         assertNotNull(profile);
-        assertNull(profile.getInheritedName());
+        assertEmpty(profile.inheritedNames());
         assertNull(profile.getDeclaredRankSetting("measurement", RankProfile.RankSetting.Type.RANKTYPE));
         assertEquals(RankType.EMPTY,
                      profile.getRankSetting("measurement", RankProfile.RankSetting.Type.RANKTYPE).getValue());
-        profile=rankProfileRegistry.get(schema, "experimental");
+        profile = rankProfileRegistry.get(schema, "experimental");
         assertNotNull(profile);
-        assertEquals("default",profile.getInheritedName());
+        assertEquals("default", profile.inheritedNames().get(0));
         assertEquals(RankType.IDENTITY,
                      profile.getDeclaredRankSetting("measurement", RankProfile.RankSetting.Type.RANKTYPE).getValue());
 
-        profile=rankProfileRegistry.get(schema, "other");
+        profile = rankProfileRegistry.get(schema, "other");
         assertNotNull(profile);
-        assertEquals("experimental",profile.getInheritedName());
+        assertEquals("experimental", profile.inheritedNames().get(0));
 
         // The extra-document field
-        SDField exact= schema.getConcreteField("exact");
-        assertNotNull("Extra field was parsed",exact);
-        assertEquals("exact",exact.getName());
-        assertEquals(Stemming.NONE,exact.getStemming());
+        SDField exact = schema.getConcreteField("exact");
+        assertNotNull("Extra field was parsed", exact);
+        assertEquals("exact", exact.getName());
+        assertEquals(Stemming.NONE, exact.getStemming());
         assertFalse(exact.getNormalizing().doRemoveAccents());
         assertEquals("{ input title . \" \" . input category | tokenize | summary exact | index exact; }",
                      exact.getIndexingScript().toString());
@@ -179,10 +180,10 @@ public class SchemaImporterTestCase extends AbstractSchemaTestCase {
     @Test
     public void testIdImporting() throws IOException, ParseException {
         Schema schema = ApplicationBuilder.buildFromFile("src/test/examples/strange.sd");
-        SDField idecidemyide=(SDField) schema.getDocument().getField("idecidemyide");
-        assertEquals(5,idecidemyide.getId());
-        SDField sodoi=(SDField) schema.getDocument().getField("sodoi");
-        assertEquals(7,sodoi.getId());
+        SDField idecidemyide = (SDField)schema.getDocument().getField("idecidemyide");
+        assertEquals(5, idecidemyide.getId());
+        SDField sodoi = (SDField) schema.getDocument().getField("sodoi");
+        assertEquals(7, sodoi.getId());
     }
 
 }
diff --git a/config-model/src/test/java/com/yahoo/searchdefinition/SchemaTestCase.java b/config-model/src/test/java/com/yahoo/searchdefinition/SchemaTestCase.java
index d012f330328..818e05a46f0 100644
--- a/config-model/src/test/java/com/yahoo/searchdefinition/SchemaTestCase.java
+++ b/config-model/src/test/java/com/yahoo/searchdefinition/SchemaTestCase.java
@@ -187,7 +187,7 @@ public class SchemaTestCase {
         assertNotNull(child1.getExtraField("child1_field"));
         assertNotNull(builder.getRankProfileRegistry().get(child1, "parent_profile"));
         assertNotNull(builder.getRankProfileRegistry().get(child1, "child1_profile"));
-        assertEquals("parent_profile", builder.getRankProfileRegistry().get(child1, "child1_profile").getInheritedName());
+        assertEquals("parent_profile", builder.getRankProfileRegistry().get(child1, "child1_profile").inheritedNames().get(0));
         assertNotNull(child1.rankingConstants().get("parent_constant"));
         assertNotNull(child1.rankingConstants().get("child1_constant"));
         assertTrue(child1.rankingConstants().asMap().containsKey("parent_constant"));
@@ -222,7 +222,7 @@ public class SchemaTestCase {
         assertNotNull(child2.getExtraField("child2_field"));
         assertNotNull(builder.getRankProfileRegistry().get(child2, "parent_profile"));
         assertNotNull(builder.getRankProfileRegistry().get(child2, "child2_profile"));
-        assertEquals("parent_profile", builder.getRankProfileRegistry().get(child2, "child2_profile").getInheritedName());
+        assertEquals("parent_profile", builder.getRankProfileRegistry().get(child2, "child2_profile").inheritedNames().get(0));
         assertNotNull(child2.rankingConstants().get("parent_constant"));
         assertNotNull(child2.rankingConstants().get("child2_constant"));
         assertTrue(child2.rankingConstants().asMap().containsKey("parent_constant"));
diff --git a/config-model/src/test/java/com/yahoo/searchdefinition/processing/RankingExpressionWithOnnxTestCase.java b/config-model/src/test/java/com/yahoo/searchdefinition/processing/RankingExpressionWithOnnxTestCase.java
index 2a9d64767ba..d44c102a5c3 100644
--- a/config-model/src/test/java/com/yahoo/searchdefinition/processing/RankingExpressionWithOnnxTestCase.java
+++ b/config-model/src/test/java/com/yahoo/searchdefinition/processing/RankingExpressionWithOnnxTestCase.java
@@ -259,7 +259,7 @@ public class RankingExpressionWithOnnxTestCase {
     public void testFunctionGeneration() {
         final String name = "small_constants_and_functions";
         final String rankProfiles =
-                "  rank-profile my_profile {\n" +
+                        "  rank-profile my_profile {\n" +
                         "    function input() {\n" +
                         "      expression: tensor<float>(d0[3])(0.0)\n" +
                         "    }\n" +