Remove unused params from SSource and Walker (#31935)

The "source" field in SSource seems unused. If removed, it can also be removed
from the ctor, which in turn makes is possible to delete the sourceText in the
Walker class.

Author: Christoph Büscher

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

@@ -29,7 +29,6 @@
 import org.antlr.v4.runtime.atn.PredictionMode;
 import org.antlr.v4.runtime.tree.TerminalNode;
 import org.elasticsearch.painless.CompilerSettings;
-import org.elasticsearch.painless.lookup.PainlessLookup;
 import org.elasticsearch.painless.Globals;
 import org.elasticsearch.painless.Location;
 import org.elasticsearch.painless.Operation;
@@ -107,6 +106,7 @@
 import org.elasticsearch.painless.antlr.PainlessParser.TryContext;
 import org.elasticsearch.painless.antlr.PainlessParser.VariableContext;
 import org.elasticsearch.painless.antlr.PainlessParser.WhileContext;
+import org.elasticsearch.painless.lookup.PainlessLookup;
 import org.elasticsearch.painless.node.AExpression;
 import org.elasticsearch.painless.node.ANode;
 import org.elasticsearch.painless.node.AStatement;
@@ -184,7 +184,6 @@ public static SSource buildPainlessTree(ScriptClassInfo mainMethod, MainMethodRe
     private final CompilerSettings settings;
     private final Printer debugStream;
     private final String sourceName;
-    private final String sourceText;
     private final PainlessLookup painlessLookup;
 
     private final Deque<Reserved> reserved = new ArrayDeque<>();
@@ -198,7 +197,6 @@ private Walker(ScriptClassInfo scriptClassInfo, MainMethodReserved reserved, Str
         this.debugStream = debugStream;
         this.settings = settings;
         this.sourceName = Location.computeSourceName(sourceName);
-        this.sourceText = sourceText;
         this.globals = new Globals(new BitSet(sourceText.length()));
         this.painlessLookup = painlessLookup;
         this.source = (SSource)visit(buildAntlrTree(sourceText));
@@ -267,7 +265,7 @@ public ANode visitSource(SourceContext ctx) {
             statements.add((AStatement)visit(ctx.dstatement()));
         }
 
-        return new SSource(scriptClassInfo, settings, sourceName, sourceText, debugStream, (MainMethodReserved)reserved.pop(),
+        return new SSource(scriptClassInfo, settings, sourceName, debugStream, (MainMethodReserved)reserved.pop(),
                            location(ctx), functions, globals, statements);
     }
 

modules/lang-painless/src/main/java/org/elasticsearch/painless/node/SSource.java

@@ -21,9 +21,6 @@
 
 import org.elasticsearch.painless.CompilerSettings;
 import org.elasticsearch.painless.Constant;
-import org.elasticsearch.painless.lookup.PainlessLookup;
-import org.elasticsearch.painless.lookup.PainlessMethod;
-import org.elasticsearch.painless.lookup.PainlessMethodKey;
 import org.elasticsearch.painless.Globals;
 import org.elasticsearch.painless.Locals;
 import org.elasticsearch.painless.Locals.Variable;
@@ -32,6 +29,9 @@
 import org.elasticsearch.painless.ScriptClassInfo;
 import org.elasticsearch.painless.SimpleChecksAdapter;
 import org.elasticsearch.painless.WriterConstants;
+import org.elasticsearch.painless.lookup.PainlessLookup;
+import org.elasticsearch.painless.lookup.PainlessMethod;
+import org.elasticsearch.painless.lookup.PainlessMethodKey;
 import org.elasticsearch.painless.node.SFunction.FunctionReserved;
 import org.objectweb.asm.ClassVisitor;
 import org.objectweb.asm.ClassWriter;
@@ -130,7 +130,6 @@ public int getMaxLoopCounter() {
     private final ScriptClassInfo scriptClassInfo;
     private final CompilerSettings settings;
     private final String name;
-    private final String source;
     private final Printer debugStream;
     private final MainMethodReserved reserved;
     private final List<SFunction> functions;
@@ -141,14 +140,12 @@ public int getMaxLoopCounter() {
     private final List<org.objectweb.asm.commons.Method> getMethods;
     private byte[] bytes;
 
-    public SSource(ScriptClassInfo scriptClassInfo, CompilerSettings settings, String name, String source, Printer debugStream,
-                   MainMethodReserved reserved, Location location,
-                   List<SFunction> functions, Globals globals, List<AStatement> statements) {
+    public SSource(ScriptClassInfo scriptClassInfo, CompilerSettings settings, String name, Printer debugStream,
+            MainMethodReserved reserved, Location location, List<SFunction> functions, Globals globals, List<AStatement> statements) {
         super(location);
         this.scriptClassInfo = Objects.requireNonNull(scriptClassInfo);
         this.settings = Objects.requireNonNull(settings);
         this.name = Objects.requireNonNull(name);
-        this.source = Objects.requireNonNull(source);
         this.debugStream = debugStream;
         this.reserved = Objects.requireNonNull(reserved);
         // process any synthetic functions generated by walker (because right now, thats still easy)