feat: add missing extension YAMLs and test for completeness

core/build.gradle.kts

@@ -87,6 +87,7 @@ dependencies {
   testImplementation(platform(libs.junit.bom))
   testImplementation(libs.protobuf.java.util)
   testImplementation(libs.guava)
+  testImplementation(libs.bundles.jackson)
 
   testImplementation(libs.junit.jupiter)
   testRuntimeOnly(libs.junit.platform.launcher)

core/src/main/java/io/substrait/extension/DefaultExtensionCatalog.java

@@ -14,6 +14,10 @@ public class DefaultExtensionCatalog {
   public static final String FUNCTIONS_AGGREGATE_APPROX =
       "extension:io.substrait:functions_aggregate_approx";
 
+  /** Extension identifier for aggregate functions with decimal output. */
+  public static final String FUNCTIONS_AGGREGATE_DECIMAL_OUTPUT =
+      "extension:io.substrait:functions_aggregate_decimal_output";
+
   /** Extension identifier for generic aggregate functions. */
   public static final String FUNCTIONS_AGGREGATE_GENERIC =
       "extension:io.substrait:functions_aggregate_generic";
@@ -37,6 +41,9 @@ public class DefaultExtensionCatalog {
   /** Extension identifier for geometry functions. */
   public static final String FUNCTIONS_GEOMETRY = "extension:io.substrait:functions_geometry";
 
+  /** Extension identifier for list functions. */
+  public static final String FUNCTIONS_LIST = "extension:io.substrait:functions_list";
+
   /** Extension identifier for logarithmic functions. */
   public static final String FUNCTIONS_LOGARITHMIC = "extension:io.substrait:functions_logarithmic";
 
@@ -78,7 +85,10 @@ private static SimpleExtension.ExtensionCollection loadDefaultCollection() {
                 "logarithmic",
                 "rounding",
                 "rounding_decimal",
+                "set",
                 "string")
+            // TODO(#688): functions_list.yaml is not loaded here because it uses lambda type
+            // expressions (e.g. func<any1 -> any2>) that are not yet supported by the type parser.
             .stream()
             .map(c -> String.format("/functions_%s.yaml", c))
             .collect(Collectors.toList());

core/src/main/java/io/substrait/extension/SimpleExtension.java

@@ -680,6 +680,11 @@ public ScalarFunctionVariant getScalarFunction(FunctionAnchor anchor) {
               anchor.key(), anchor.urn()));
     }
 
+    /** Returns true if the given URN has any functions or types loaded in this collection. */
+    public boolean containsUrn(String urn) {
+      return urnSupplier.get().contains(urn) || types().stream().anyMatch(t -> t.urn().equals(urn));
+    }
+
     private void checkUrn(String name) {
       if (urnSupplier.get().contains(name)) {
         return;

core/src/test/java/io/substrait/extension/DefaultExtensionCatalogTest.java

@@ -0,0 +1,66 @@
+package io.substrait.extension;
+
+import static io.substrait.extension.DefaultExtensionCatalog.DEFAULT_COLLECTION;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;
+import java.io.File;
+import java.io.IOException;
+import java.util.List;
+import java.util.Set;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Verifies that every extension YAML in substrait/extensions is loaded by {@link
+ * DefaultExtensionCatalog}.
+ */
+class DefaultExtensionCatalogTest {
+
+  private static final Set<String> UNSUPPORTED_FILES =
+      Set.of(
+          // TODO: aggregate_decimal_output defines count and approx_count_distinct with
+          //  decimal<38,0> return types instead of i64. When loaded alongside aggregate_generic,
+          //  the same function key (e.g. count:any) maps to the same Calcite operator twice,
+          //  which breaks the reverse lookup in FunctionConverter.getSqlOperatorFromSubstraitFunc.
+          //  Fixing this requires either deduplicating the operator map or adding type-based
+          //  disambiguation for aggregate functions.
+          "functions_aggregate_decimal_output.yaml",
+          "functions_geometry.yaml", // user-defined types not supported in Calcite type conversion
+          "functions_list.yaml", // TODO(#688): remove once lambda types are supported
+          "type_variations.yaml", // type variations not yet supported by extension loader
+          "unknown.yaml" // unknown type extension not yet loaded
+          );
+
+  private static final ObjectMapper YAML_MAPPER = new ObjectMapper(new YAMLFactory());
+
+  @Test
+  void allExtensionYamlFilesAreLoaded() throws IOException {
+    List<File> yamlFiles = getExtensionYamlFiles();
+
+    for (File file : yamlFiles) {
+      if (UNSUPPORTED_FILES.contains(file.getName())) {
+        continue;
+      }
+      String urn = parseUrn(file);
+      assertTrue(
+          DEFAULT_COLLECTION.containsUrn(urn),
+          file.getName() + " not loaded by DefaultExtensionCatalog (urn: " + urn + ")");
+    }
+  }
+
+  private static String parseUrn(File yamlFile) throws IOException {
+    JsonNode doc = YAML_MAPPER.readTree(yamlFile);
+    JsonNode urnNode = doc.get("urn");
+    return urnNode == null ? null : urnNode.asText();
+  }
+
+  private static List<File> getExtensionYamlFiles() {
+    File extensionsDir = new File("../substrait/extensions");
+    assertTrue(extensionsDir.isDirectory(), "substrait/extensions directory not found");
+    File[] files = extensionsDir.listFiles((dir, name) -> name.endsWith(".yaml"));
+    assertTrue(files != null && files.length > 0, "No YAML files found");
+    return List.of(files);
+  }
+}