Add legacy override to turn on trimming for notes and expressions

Author: jasmith-hs

src/main/java/com/hubspot/jinjava/LegacyOverrides.java

@@ -16,6 +16,7 @@ public class LegacyOverrides {
     .withUseNaturalOperatorPrecedence(true)
     .withParseWhitespaceControlStrictly(true)
     .withAllowAdjacentTextNodes(true)
+    .withUseTrimmingForNotesAndExpressions(true)
     .build();
   private final boolean evaluateMapKeys;
   private final boolean iterateOverMapKeys;
@@ -25,6 +26,7 @@ public class LegacyOverrides {
   private final boolean useNaturalOperatorPrecedence;
   private final boolean parseWhitespaceControlStrictly;
   private final boolean allowAdjacentTextNodes;
+  private final boolean useTrimmingForNotesAndExpressions;
 
   private LegacyOverrides(Builder builder) {
     evaluateMapKeys = builder.evaluateMapKeys;
@@ -35,6 +37,7 @@ private LegacyOverrides(Builder builder) {
     useNaturalOperatorPrecedence = builder.useNaturalOperatorPrecedence;
     parseWhitespaceControlStrictly = builder.parseWhitespaceControlStrictly;
     allowAdjacentTextNodes = builder.allowAdjacentTextNodes;
+    useTrimmingForNotesAndExpressions = builder.useTrimmingForNotesAndExpressions;
   }
 
   public static Builder newBuilder() {
@@ -73,6 +76,10 @@ public boolean isAllowAdjacentTextNodes() {
     return allowAdjacentTextNodes;
   }
 
+  public boolean isUseTrimmingForNotesAndExpressions() {
+    return useTrimmingForNotesAndExpressions;
+  }
+
   public static class Builder {
     private boolean evaluateMapKeys = false;
     private boolean iterateOverMapKeys = false;
@@ -82,6 +89,7 @@ public static class Builder {
     private boolean useNaturalOperatorPrecedence = false;
     private boolean parseWhitespaceControlStrictly = false;
     private boolean allowAdjacentTextNodes = false;
+    private boolean useTrimmingForNotesAndExpressions = false;
 
     private Builder() {}
 
@@ -102,7 +110,10 @@ public static Builder from(LegacyOverrides legacyOverrides) {
         .withParseWhitespaceControlStrictly(
           legacyOverrides.parseWhitespaceControlStrictly
         )
-        .withAllowAdjacentTextNodes(legacyOverrides.allowAdjacentTextNodes);
+        .withAllowAdjacentTextNodes(legacyOverrides.allowAdjacentTextNodes)
+        .withUseTrimmingForNotesAndExpressions(
+          legacyOverrides.useTrimmingForNotesAndExpressions
+        );
     }
 
     public Builder withEvaluateMapKeys(boolean evaluateMapKeys) {
@@ -150,5 +161,12 @@ public Builder withAllowAdjacentTextNodes(boolean allowAdjacentTextNodes) {
       this.allowAdjacentTextNodes = allowAdjacentTextNodes;
       return this;
     }
+
+    public Builder withUseTrimmingForNotesAndExpressions(
+      boolean useTrimmingForNotesAndExpressions
+    ) {
+      this.useTrimmingForNotesAndExpressions = useTrimmingForNotesAndExpressions;
+      return this;
+    }
   }
 }

src/main/java/com/hubspot/jinjava/tree/TreeParser.java

@@ -17,6 +17,7 @@
 
 import com.google.common.collect.Iterators;
 import com.google.common.collect.PeekingIterator;
+import com.hubspot.jinjava.JinjavaConfig;
 import com.hubspot.jinjava.interpret.DisabledException;
 import com.hubspot.jinjava.interpret.JinjavaInterpreter;
 import com.hubspot.jinjava.interpret.MissingEndTagException;
@@ -102,7 +103,7 @@ public Node buildTree() {
 
   private Node nextNode() {
     Token token = scanner.next();
-    if (token.isLeftTrim()) {
+    if (token.isLeftTrim() && isTrimmingEnabledForToken(token, interpreter.getConfig())) {
       final Node lastSibling = getLastSibling();
       if (lastSibling instanceof TextNode) {
         lastSibling.getMaster().setRightTrim(true);
@@ -182,7 +183,11 @@ private Node text(TextToken textToken) {
     final Node lastSibling = getLastSibling();
 
     // if last sibling was a tag and has rightTrimAfterEnd, strip whitespace
-    if (lastSibling != null && isRightTrim(lastSibling)) {
+    if (
+      lastSibling != null &&
+      isRightTrim(lastSibling) &&
+      isTrimmingEnabledForToken(lastSibling.getMaster(), interpreter.getConfig())
+    ) {
       textToken.setLeftTrim(true);
     }
 
@@ -315,4 +320,11 @@ private void endTag(Tag tag, TagToken tagToken) {
       );
     }
   }
+
+  private boolean isTrimmingEnabledForToken(Token token, JinjavaConfig jinjavaConfig) {
+    if (token instanceof TagToken || token instanceof TextToken) {
+      return true;
+    }
+    return jinjavaConfig.getLegacyOverrides().isUseTrimmingForNotesAndExpressions();
+  }
 }

src/test/java/com/hubspot/jinjava/tree/TreeParserTest.java

@@ -229,7 +229,22 @@ public void itWarnsTwiceAgainstUnclosedBlockTag() {
   public void itTrimsNotes() {
     String expression = "A\n{#- note -#}\nB";
     final Node tree = new TreeParser(interpreter, expression).buildTree();
-    assertThat(interpreter.render(tree)).isEqualTo("AB");
+    assertThat(interpreter.render(tree)).isEqualTo("A\n\nB");
+    interpreter =
+      new Jinjava(
+        JinjavaConfig
+          .newBuilder()
+          .withLegacyOverrides(
+            LegacyOverrides
+              .newBuilder()
+              .withUseTrimmingForNotesAndExpressions(true)
+              .build()
+          )
+          .build()
+      )
+      .newInterpreter();
+    final Node newTree = new TreeParser(interpreter, expression).buildTree();
+    assertThat(interpreter.render(newTree)).isEqualTo("AB");
   }
 
   @Test
@@ -243,7 +258,22 @@ public void itMergesTextNodesWhileRespectingTrim() {
   public void itTrimsExpressions() {
     String expression = "A\n{{- 'B' -}}\nC";
     final Node tree = new TreeParser(interpreter, expression).buildTree();
-    assertThat(interpreter.render(tree)).isEqualTo("ABC");
+    assertThat(interpreter.render(tree)).isEqualTo("A\nB\nC");
+    interpreter =
+      new Jinjava(
+        JinjavaConfig
+          .newBuilder()
+          .withLegacyOverrides(
+            LegacyOverrides
+              .newBuilder()
+              .withUseTrimmingForNotesAndExpressions(true)
+              .build()
+          )
+          .build()
+      )
+      .newInterpreter();
+    final Node newTree = new TreeParser(interpreter, expression).buildTree();
+    assertThat(interpreter.render(newTree)).isEqualTo("ABC");
   }
 
   @Test