replace recursive visiting for twig extends indexer

Author: Haehnchen

src/main/java/fr/adrienbrault/idea/symfony2plugin/templating/util/TwigUtil.java

@@ -2807,29 +2807,38 @@ public static Collection<LookupElement> getBlockLookupElements(@NotNull Project
         return lookupElements;
     }
 
-    public static void visitTemplateExtends(@NotNull TwigFile twigFile,@NotNull Consumer<Pair<String, PsiElement>> consumer) {
-        twigFile.acceptChildren(new PsiRecursiveElementWalkingVisitor() {
-            @Override
-            public void visitElement(PsiElement element) {
-                if (element instanceof TwigExtendsTag) {
-                    for (String s : TwigUtil.getTwigExtendsTagTemplates((TwigExtendsTag) element)) {
-                        consumer.consume(Pair.create(TwigUtil.normalizeTemplateName(s), element));
-                    }
+    public static void visitTemplateExtends(@NotNull TwigFile twigFile, @NotNull Consumer<Pair<String, PsiElement>> consumer) {
+        for (PsiElement element : twigFile.getChildren()) {
+            // "extends" must not be nested, support 1 level at least for invalid files
+            if (element instanceof TwigBlockStatement || element.getNode().getElementType() == TwigElementTypes.IF_STATEMENT) {
+                for (PsiElement child : element.getChildren()) {
+                    visitTemplateExtendsConsumer(child, consumer);
                 }
 
-                for (TwigFileUsage extension : TWIG_FILE_USAGE_EXTENSIONS.getExtensions()) {
-                    if (!extension.isExtendsTemplate(element)) {
-                       continue;
-                    }
+                continue;
+            }
 
-                    for (String template : extension.getExtendsTemplate(element)) {
-                        consumer.consume(Pair.create(TwigUtil.normalizeTemplateName(template), element));
-                    }
-                }
+            visitTemplateExtendsConsumer(element, consumer);
+        }
+    }
 
-                super.visitElement(element);
+    private static void visitTemplateExtendsConsumer(@NotNull PsiElement element, @NotNull Consumer<Pair<String, PsiElement>> consumer) {
+        if (element instanceof TwigExtendsTag) {
+            for (String s : TwigUtil.getTwigExtendsTagTemplates((TwigExtendsTag) element)) {
+                String first = TwigUtil.normalizeTemplateName(s);
+                consumer.consume(new Pair<>(first, element));
             }
-        });
+        }
+
+        for (TwigFileUsage extension : TWIG_FILE_USAGE_EXTENSIONS.getExtensions()) {
+            if (!extension.isExtendsTemplate(element)) {
+                continue;
+            }
+
+            for (String template : extension.getExtendsTemplate(element)) {
+                consumer.consume(Pair.create(TwigUtil.normalizeTemplateName(template), element));
+            }
+        }
     }
 
     public static List<String> getIncludeTemplateUsageAsOrderedList(@NotNull Project project) {

src/test/java/fr/adrienbrault/idea/symfony2plugin/tests/stubs/indexes/TwigExtendsStubIndexTest.java

@@ -18,7 +18,11 @@ public void setUp() throws Exception {
             "{% extends '@Bar/extends.html.twig' %}\n" +
             "{% extends '@!Bar/extends_overwrite.html.twig' %}\n" +
             "{% extends ajax ? 'extends_statement_0.html.twig' : 'extends_statement_1.html.twig' %}\n" +
-            "{% extends request.ajax ? foo ~ \"extends_statement_2.html.twig\" : \"extends_statement_3.html.twig\" %}\n"
+            "{% extends request.ajax ? foo ~ \"extends_statement_2.html.twig\" : \"extends_statement_3.html.twig\" %}\n" +
+
+            // invalid cases to support
+            "{% if '' %}{% extends 'extends_nested_if.html.twig' %}{% endif %}\n" +
+            "{% block foo %}{% extends 'extends_nested_block.html.twig' %}{% endblock %}\n"
         );
     }
 
@@ -28,7 +32,7 @@ public void setUp() throws Exception {
     public void testTemplateExtendsIndexer() {
         assertIndexContains(TwigExtendsStubIndex.KEY,
             "extends.html.twig", "extends_statement_0.html.twig", "extends_statement_1.html.twig",
-            "extends_statement_3.html.twig", "@Bar/extends_overwrite.html.twig"
+            "extends_statement_3.html.twig", "@Bar/extends_overwrite.html.twig", "extends_nested_if.html.twig", "extends_nested_block.html.twig"
         );
 
         assertIndexNotContains(TwigExtendsStubIndex.KEY,