IncludeTag now respects ignore missing

Author: Achim Abeling

src/main/java/com/hubspot/jinjava/lib/tag/IncludeTag.java

@@ -73,6 +73,9 @@ public String interpret(TagNode tagNode, JinjavaInterpreter interpreter) {
     );
     templateFile = interpreter.resolveResourceLocation(templateFile);
 
+    /* check next tokens if it could be ignored if missing */
+    boolean ignoreMissing = checkIgnoreMissing(helper);
+
     try {
       interpreter
         .getContext()
@@ -108,6 +111,10 @@ public String interpret(TagNode tagNode, JinjavaInterpreter interpreter) {
 
       return interpreter.render(node, false);
     } catch (IOException e) {
+      if (ignoreMissing) {
+        return "";
+      }
+
       throw new InterpretException(
         e.getMessage(),
         e,
@@ -120,6 +127,19 @@ public String interpret(TagNode tagNode, JinjavaInterpreter interpreter) {
     }
   }
 
+  /**
+   * Returns true if the next two tokens are "ignore" and "missing"
+   * @param helper
+   */
+  private boolean checkIgnoreMissing(HelperStringTokenizer helper) {
+    if (helper.hasNext() && "ignore".equals(helper.next())) {
+      if (helper.hasNext() && "missing".equals(helper.next())) {
+        return true;
+      }
+    }
+    return false;
+  }
+
   @Override
   public String getEndTagName() {
     return null;

src/test/java/com/hubspot/jinjava/lib/tag/IncludeTagTest.java

@@ -207,4 +207,16 @@ public void itAvoidsTagCycleExceptionInsideExtendedFiles() throws Exception {
     );
     assertThat(result).isEqualTo("Extended text, will be rendered");
   }
+
+  @Test
+  public void itIgnoresMissing() throws IOException {
+    String result = jinjava.render(
+      Resources.toString(
+        Resources.getResource("tags/includetag/missing-include.jinja"),
+        StandardCharsets.UTF_8
+      ),
+      new HashMap<String, Object>()
+    );
+    assertThat(result).containsSequence("AB");
+  }
 }

src/test/resources/tags/includetag/missing-include.jinja

@@ -0,0 +1 @@
+A{% include "foobar" ignore missing %}B