Move regex error to node (#45813)

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

@@ -817,11 +817,6 @@ public final class Walker extends PainlessParserBaseVisitor<ANode> {
 
     @Override
     public ANode visitRegex(RegexContext ctx) {
-        if (false == settings.areRegexesEnabled()) {
-            throw location(ctx).createError(new IllegalStateException("Regexes are disabled. Set [script.painless.regex.enabled] to [true] "
-                    + "in elasticsearch.yaml to allow them. Be careful though, regexes break out of Painless's protection against deep "
-                    + "recursion and long loops."));
-        }
         String text = ctx.REGEX().getText();
         int lastSlash = text.lastIndexOf('/');
         String pattern = text.substring(1, lastSlash);

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

@@ -40,6 +40,8 @@ public final class ERegex extends AExpression {
     private final int flags;
     private Constant constant;
 
+    private CompilerSettings settings;
+
     public ERegex(Location location, String pattern, String flagsString) {
         super(location);
 
@@ -56,7 +58,7 @@ public final class ERegex extends AExpression {
 
     @Override
     void storeSettings(CompilerSettings settings) {
-        // do nothing
+        this.settings = settings;
     }
 
     @Override
@@ -66,6 +68,12 @@ public final class ERegex extends AExpression {
 
     @Override
     void analyze(Locals locals) {
+        if (false == settings.areRegexesEnabled()) {
+            throw createError(new IllegalStateException("Regexes are disabled. Set [script.painless.regex.enabled] to [true] "
+                    + "in elasticsearch.yaml to allow them. Be careful though, regexes break out of Painless's protection against deep "
+                    + "recursion and long loops."));
+        }
+
         if (!read) {
             throw createError(new IllegalArgumentException("Regex constant may only be read [" + pattern + "]."));
         }

modules/lang-painless/src/test/java/org/elasticsearch/painless/WhenThingsGoWrongTests.java

@@ -262,7 +262,7 @@ public class WhenThingsGoWrongTests extends ScriptTestCase {
     }
 
     public void testRegexDisabledByDefault() {
-        IllegalStateException e = expectThrows(IllegalStateException.class, () -> exec("return 'foo' ==~ /foo/"));
+        IllegalStateException e = expectScriptThrows(IllegalStateException.class, () -> exec("return 'foo' ==~ /foo/"));
         assertEquals("Regexes are disabled. Set [script.painless.regex.enabled] to [true] in elasticsearch.yaml to allow them. "
                 + "Be careful though, regexes break out of Painless's protection against deep recursion and long loops.", e.getMessage());
     }