Bring back support for generating inline_cast.json for kibana

x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/CommandDocsTests.java

@@ -58,11 +58,6 @@ public TestDocsV3Support() {
             super("commands", "commands", CommandDocsTests.class, null, callbacksFromSystemProperty());
         }
 
-        @Override
-        protected void renderSignature() throws IOException {
-            // Not implemented
-        }
-
         @Override
         protected void renderDocs() throws IOException {
             // Not implemented

x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/expression/function/DocsV3Support.java

@@ -560,13 +560,18 @@ void writeToTempSnippetsDir(String subdir, String str) throws IOException {
         callbacks.write(dir, name, "md", str, false);
     }
 
-    void writeToTempKibanaDir(String subdir, String extension, String str) throws IOException {
+    protected void writeToTempKibanaDir(String subdir, String extension, String str) throws IOException {
         // We have to write to a tempdir because it’s all test are allowed to write to. Gradle can move them.
-        Path dir = PathUtils.get(System.getProperty("java.io.tmpdir")).resolve("esql").resolve("kibana").resolve(subdir).resolve(category);
+        Path dir = PathUtils.get(System.getProperty("java.io.tmpdir")).resolve("esql").resolve("kibana").resolve(subdir);
+        if (category != null) {
+            dir = dir.resolve(category);
+        }
         callbacks.write(dir, name, extension, str, true);
     }
 
-    protected abstract void renderSignature() throws IOException;
+    public void renderSignature() throws IOException {
+        // Only functions and operators currently have signatures to render, so only they should override this method.
+    }
 
     protected abstract void renderDocs() throws Exception;
 
@@ -586,7 +591,7 @@ private FunctionDocsSupport(String name, Class<?> testClass, Callbacks callbacks
         }
 
         @Override
-        protected void renderSignature() throws IOException {
+        public void renderSignature() throws IOException {
             if (callbacks.supportsRendering() == false) {
                 return;
             }
@@ -1003,11 +1008,6 @@ public CommandsDocsSupport(
             this.observabilityTier = null;
         }
 
-        @Override
-        public void renderSignature() throws IOException {
-            // Unimplemented until we make command docs dynamically generated
-        }
-
         @Override
         public void renderDocs() throws Exception {
             // Currently we only render either signatures or kibana definition files,
@@ -1094,11 +1094,6 @@ public SettingsDocsSupport(QuerySettingDef<?> setting, Class<?> testClass, Callb
             this.setting = setting;
         }
 
-        @Override
-        public void renderSignature() throws IOException {
-            // Unimplemented until we make setting docs dynamically generated
-        }
-
         @Override
         public void renderDocs() throws Exception {
             // TODO docs for settings

x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/parser/StatementParserTests.java

@@ -9,6 +9,7 @@
 
 import org.apache.lucene.util.BytesRef;
 import org.elasticsearch.Build;
+import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.logging.LoggerMessageFormat;
 import org.elasticsearch.common.lucene.BytesRefs;
 import org.elasticsearch.common.settings.Settings;
@@ -32,6 +33,7 @@
 import org.elasticsearch.xpack.esql.core.type.DataType;
 import org.elasticsearch.xpack.esql.expression.Order;
 import org.elasticsearch.xpack.esql.expression.UnresolvedNamePattern;
+import org.elasticsearch.xpack.esql.expression.function.DocsV3Support;
 import org.elasticsearch.xpack.esql.expression.function.EsqlFunctionRegistry;
 import org.elasticsearch.xpack.esql.expression.function.UnresolvedFunction;
 import org.elasticsearch.xpack.esql.expression.function.aggregate.FilteredExpression;
@@ -86,7 +88,9 @@
 import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
+import java.util.Set;
 import java.util.function.Function;
 import java.util.stream.Stream;
 
@@ -4221,8 +4225,7 @@ public void testInlineCast() throws IOException {
             .resolve("definition");
         Files.createDirectories(dir);
         Path file = dir.resolve("inline_cast.json");
-        try (XContentBuilder report = new XContentBuilder(JsonXContent.jsonXContent, Files.newOutputStream(file))) {
-            report.humanReadable(true).prettyPrint();
+        try (XContentBuilder report = JsonXContent.contentBuilder().humanReadable(true).prettyPrint().lfAtEnd()) {
             report.startObject();
             List<String> namesAndAliases = new ArrayList<>(DataType.namesAndAliases());
             if (EsqlCapabilities.Cap.SPATIAL_GRID_TYPES.isEnabled() == false) {
@@ -4241,13 +4244,29 @@ public void testInlineCast() throws IOException {
                 org.elasticsearch.xpack.esql.core.expression.function.Function functionCall =
                     (org.elasticsearch.xpack.esql.core.expression.function.Function) row.fields().get(0).child();
                 assertThat(functionCall.dataType(), equalTo(expectedType));
-                report.field(nameOrAlias, registry.snapshotRegistry().functionName(functionCall.getClass()));
+                report.field(nameOrAlias, registry.snapshotRegistry().functionName(functionCall.getClass()).toLowerCase(Locale.ROOT));
             }
             report.endObject();
+            String rendered = Strings.toString(report);
+            (new TestInlineCastDocsSupport(rendered)).renderDocs();
         }
         logger.info("Wrote to file: {}", file);
     }
 
+    private static class TestInlineCastDocsSupport extends DocsV3Support {
+        private final String rendered;
+
+        protected TestInlineCastDocsSupport(String rendered) {
+            super(null, "inline_cast", StatementParserTests.class, Set::of, new DocsV3Support.WriteCallbacks());
+            this.rendered = rendered;
+        }
+
+        @Override
+        protected void renderDocs() throws IOException {
+            this.writeToTempKibanaDir("definition", "json", rendered);
+        }
+    }
+
     public void testTooBigQuery() {
         StringBuilder query = new StringBuilder("FROM foo | EVAL a = a");
         while (query.length() < EsqlParser.MAX_LENGTH) {