Remove ScriptClassInfo from Walker (#60316)

This change covers two items:

* This removes ScriptClassInfo from Walker so that we can separate semantic checking from user tree 
building entirely. ScriptClassInfo is added to a PainlessSemanticAnalysisPhase and a 
PainlessSemanticHeaderPhase which both extend from their respective Default classes. These classes 
allow for the special casing of the execute method where ScriptClassInfo is used to inject the 
appropriate parameters for the execute method. This allows us to potentially check and use a script 
across more than one context which is especially relevant for stored scripts.

* This removes the BootstrapInjectionPhase and the ScriptInjectionPhase instead moving the code 
more appropriately to the other phases instead.

modules/lang-painless/src/main/java/org/elasticsearch/painless/Compiler.java

@@ -24,10 +24,10 @@
 import org.elasticsearch.painless.ir.ClassNode;
 import org.elasticsearch.painless.lookup.PainlessLookup;
 import org.elasticsearch.painless.node.SClass;
-import org.elasticsearch.painless.phase.DefaultSemanticAnalysisPhase;
-import org.elasticsearch.painless.phase.DefaultSemanticHeaderPhase;
-import org.elasticsearch.painless.phase.DefaultUserTreeToIRTreeVisitor;
 import org.elasticsearch.painless.phase.DocFieldsPhase;
+import org.elasticsearch.painless.phase.PainlessSemanticAnalysisPhase;
+import org.elasticsearch.painless.phase.PainlessSemanticHeaderPhase;
+import org.elasticsearch.painless.phase.PainlessUserTreeToIRTreePhase;
 import org.elasticsearch.painless.spi.Whitelist;
 import org.elasticsearch.painless.symbol.Decorations.IRNodeDecoration;
 import org.elasticsearch.painless.symbol.ScriptScope;
@@ -214,16 +214,14 @@ private static void addFactoryMethod(Map<String, Class<?>> additionalClasses, Cl
     ScriptScope compile(Loader loader, String name, String source, CompilerSettings settings) {
         String scriptName = Location.computeSourceName(name);
         ScriptClassInfo scriptClassInfo = new ScriptClassInfo(painlessLookup, scriptClass);
-        SClass root = Walker.buildPainlessTree(scriptClassInfo, scriptName, source, settings);
+        SClass root = Walker.buildPainlessTree(scriptName, source, settings);
         ScriptScope scriptScope = new ScriptScope(painlessLookup, settings, scriptClassInfo, scriptName, source, root.getIdentifier() + 1);
-        new DefaultSemanticHeaderPhase().visitClass(root, scriptScope);
-        new DefaultSemanticAnalysisPhase().visitClass(root, scriptScope);
-        new DefaultUserTreeToIRTreeVisitor().visitClass(root, scriptScope);
+        new PainlessSemanticHeaderPhase().visitClass(root, scriptScope);
+        new PainlessSemanticAnalysisPhase().visitClass(root, scriptScope);
         // TODO(stu): Make this phase optional #60156
         new DocFieldsPhase().visitClass(root, scriptScope);
+        new PainlessUserTreeToIRTreePhase().visitClass(root, scriptScope);
         ClassNode classNode = (ClassNode)scriptScope.getDecoration(root, IRNodeDecoration.class).getIRNode();
-        DefBootstrapInjectionPhase.phase(classNode);
-        ScriptInjectionPhase.phase(scriptScope, classNode);
         byte[] bytes = classNode.write();
 
         try {
@@ -249,17 +247,15 @@ ScriptScope compile(Loader loader, String name, String source, CompilerSettings
     byte[] compile(String name, String source, CompilerSettings settings, Printer debugStream) {
         String scriptName = Location.computeSourceName(name);
         ScriptClassInfo scriptClassInfo = new ScriptClassInfo(painlessLookup, scriptClass);
-        SClass root = Walker.buildPainlessTree(scriptClassInfo, scriptName, source, settings);
+        SClass root = Walker.buildPainlessTree(scriptName, source, settings);
         ScriptScope scriptScope = new ScriptScope(painlessLookup, settings, scriptClassInfo, scriptName, source, root.getIdentifier() + 1);
-        new DefaultSemanticHeaderPhase().visitClass(root, scriptScope);
-        new DefaultSemanticAnalysisPhase().visitClass(root, scriptScope);
-        new DefaultUserTreeToIRTreeVisitor().visitClass(root, scriptScope);
+        new PainlessSemanticHeaderPhase().visitClass(root, scriptScope);
+        new PainlessSemanticAnalysisPhase().visitClass(root, scriptScope);
         // TODO(stu): Make this phase optional #60156
         new DocFieldsPhase().visitClass(root, scriptScope);
+        new PainlessUserTreeToIRTreePhase().visitClass(root, scriptScope);
         ClassNode classNode = (ClassNode)scriptScope.getDecoration(root, IRNodeDecoration.class).getIRNode();
         classNode.setDebugStream(debugStream);
-        DefBootstrapInjectionPhase.phase(classNode);
-        ScriptInjectionPhase.phase(scriptScope, classNode);
 
         return classNode.write();
     }

modules/lang-painless/src/main/java/org/elasticsearch/painless/antlr/Walker.java

@@ -31,7 +31,6 @@
 import org.elasticsearch.painless.CompilerSettings;
 import org.elasticsearch.painless.Location;
 import org.elasticsearch.painless.Operation;
-import org.elasticsearch.painless.ScriptClassInfo;
 import org.elasticsearch.painless.antlr.PainlessParser.AddsubContext;
 import org.elasticsearch.painless.antlr.PainlessParser.AfterthoughtContext;
 import org.elasticsearch.painless.antlr.PainlessParser.ArgumentContext;
@@ -107,7 +106,6 @@
 import org.elasticsearch.painless.antlr.PainlessParser.TypeContext;
 import org.elasticsearch.painless.antlr.PainlessParser.VariableContext;
 import org.elasticsearch.painless.antlr.PainlessParser.WhileContext;
-import org.elasticsearch.painless.lookup.PainlessLookupUtility;
 import org.elasticsearch.painless.node.AExpression;
 import org.elasticsearch.painless.node.ANode;
 import org.elasticsearch.painless.node.AStatement;
@@ -161,29 +159,31 @@
 import java.util.Collections;
 import java.util.List;
 
+import static java.util.Collections.emptyList;
+
 /**
  * Converts the ANTLR tree to a Painless tree.
  */
 public final class Walker extends PainlessParserBaseVisitor<ANode> {
 
-    public static SClass buildPainlessTree(ScriptClassInfo mainMethod, String sourceName, String sourceText, CompilerSettings settings) {
-        return new Walker(mainMethod, sourceName, sourceText, settings).source;
+    public static SClass buildPainlessTree(String sourceName, String sourceText, CompilerSettings settings) {
+        return new Walker(sourceName, sourceText, settings).source;
     }
 
-    private final ScriptClassInfo scriptClassInfo;
-    private final SClass source;
     private final CompilerSettings settings;
     private final String sourceName;
 
     private int identifier;
 
-    private Walker(ScriptClassInfo scriptClassInfo, String sourceName, String sourceText, CompilerSettings settings) {
-        this.scriptClassInfo = scriptClassInfo;
+    private final SClass source;
+
+    private Walker(String sourceName, String sourceText, CompilerSettings settings) {
         this.settings = settings;
         this.sourceName = sourceName;
-        this.source = (SClass)visit(buildAntlrTree(sourceText));
 
         this.identifier = 0;
+
+        this.source = (SClass)visit(buildAntlrTree(sourceText));
     }
 
     private int nextIdentifier() {
@@ -247,32 +247,13 @@ public ANode visitSource(SourceContext ctx) {
         // part of the overall class
         List<AStatement> statements = new ArrayList<>();
 
-        // add gets methods as declarations available for the user as variables
-        for (int index = 0; index < scriptClassInfo.getGetMethods().size(); ++index) {
-            org.objectweb.asm.commons.Method method = scriptClassInfo.getGetMethods().get(index);
-            String name = method.getName().substring(3);
-            name = Character.toLowerCase(name.charAt(0)) + name.substring(1);
-
-            statements.add(new SDeclaration(nextIdentifier(), location(ctx),
-                    PainlessLookupUtility.typeToCanonicalTypeName(scriptClassInfo.getGetReturns().get(index)), name, null));
-        }
-
         for (StatementContext statement : ctx.statement()) {
             statements.add((AStatement)visit(statement));
         }
 
-        String returnCanonicalTypeName = PainlessLookupUtility.typeToCanonicalTypeName(scriptClassInfo.getExecuteMethodReturnType());
-        List<String> paramTypes = new ArrayList<>();
-        List<String> paramNames = new ArrayList<>();
-
-        for (ScriptClassInfo.MethodArgument argument : scriptClassInfo.getExecuteArguments()) {
-            paramTypes.add(PainlessLookupUtility.typeToCanonicalTypeName(argument.getClazz()));
-            paramNames.add(argument.getName());
-        }
-
         // generate the execute method from the collected statements and parameters
-        SFunction execute = new SFunction(nextIdentifier(), location(ctx), returnCanonicalTypeName, "execute", paramTypes, paramNames,
-                new SBlock(nextIdentifier(), location(ctx), statements), true, false, false, true);
+        SFunction execute = new SFunction(nextIdentifier(), location(ctx), "<internal>", "execute", emptyList(), emptyList(),
+                new SBlock(nextIdentifier(), location(ctx), statements), false, false, false, false);
         functions.add(execute);
 
         return new SClass(nextIdentifier(), location(ctx), functions);

modules/lang-painless/src/main/java/org/elasticsearch/painless/phase/DefaultSemanticAnalysisPhase.java

@@ -261,13 +261,6 @@ public void visitFunction(SFunction userFunctionNode, ScriptScope scriptScope) {
         if (methodEscape) {
             functionScope.setCondition(userFunctionNode, MethodEscape.class);
         }
-
-        // TODO: do not specialize for execute
-        // TODO: https://github.com/elastic/elasticsearch/issues/51841
-        if ("execute".equals(functionName)) {
-            scriptScope.setUsedVariables(functionScope.getUsedVariables());
-        }
-        // TODO: end
     }
 
     /**

modules/lang-painless/src/main/java/org/elasticsearch/painless/phase/DefaultSemanticHeaderPhase.java

@@ -42,8 +42,9 @@ public void visitFunction(SFunction userFunctionNode, ScriptScope scriptScope) {
         String functionName = userFunctionNode.getFunctionName();
         List<String> canonicalTypeNameParameters = userFunctionNode.getCanonicalTypeNameParameters();
         List<String> parameterNames = userFunctionNode.getParameterNames();
+        int parameterCount = canonicalTypeNameParameters.size();
 
-        if (canonicalTypeNameParameters.size() != parameterNames.size()) {
+        if (parameterCount != parameterNames.size()) {
             throw userFunctionNode.createError(new IllegalStateException("invalid function definition: " +
                     "parameter types size [" + canonicalTypeNameParameters.size() + "] is not equal to " +
                     "parameter names size [" + parameterNames.size() + "] for function [" + functionName +"]"));