fix: reconstruct namespace root of dotted {% set ns.attr %} across scopes

src/main/java/com/hubspot/jinjava/lib/tag/eager/EagerBlockSetTagStrategy.java

@@ -166,6 +166,7 @@ protected Triple<String, String, String> getPrefixTokenAndSuffix(
           interpreter,
           DeferredToken
             .builderFromImage(joiner.toString(), tagNode.getMaster())
+            .addUsedDeferredWords(getNamespaceRootsForDottedSet(variables, interpreter))
             .addSetDeferredWords(Stream.of(variables))
             .build()
         )

src/main/java/com/hubspot/jinjava/lib/tag/eager/EagerInlineSetTagStrategy.java

@@ -97,6 +97,7 @@ public Triple<String, String, String> getPrefixTokenAndSuffix(
         DeferredToken
           .builderFromImage(joiner.toString(), tagNode.getMaster())
           .addUsedDeferredWords(eagerExecutionResult.getResult().getDeferredWords())
+          .addUsedDeferredWords(getNamespaceRootsForDottedSet(variables, interpreter))
           .addSetDeferredWords(Arrays.stream(variables).map(String::trim))
           .build()
       )

src/main/java/com/hubspot/jinjava/lib/tag/eager/EagerSetTagStrategy.java

@@ -6,6 +6,7 @@
 import com.hubspot.jinjava.interpret.MetaContextVariables;
 import com.hubspot.jinjava.lib.tag.SetTag;
 import com.hubspot.jinjava.loader.RelativePathResolver;
+import com.hubspot.jinjava.objects.Namespace;
 import com.hubspot.jinjava.tree.TagNode;
 import com.hubspot.jinjava.util.EagerReconstructionUtils;
 import com.hubspot.jinjava.util.PrefixToPreserveState;
@@ -26,6 +27,19 @@ protected EagerSetTagStrategy(SetTag setTag) {
     this.setTag = setTag;
   }
 
+  protected static Stream<String> getNamespaceRootsForDottedSet(
+    String[] variables,
+    JinjavaInterpreter interpreter
+  ) {
+    return Arrays
+      .stream(variables)
+      .map(String::trim)
+      .filter(variable -> variable.contains("."))
+      .map(variable -> variable.substring(0, variable.indexOf('.')))
+      .distinct()
+      .filter(root -> interpreter.getContext().get(root) instanceof Namespace);
+  }
+
   public String run(TagNode tagNode, JinjavaInterpreter interpreter) {
     int eqPos = tagNode.getHelpers().indexOf('=');
     String[] variables;

src/test/java/com/hubspot/jinjava/EagerTest.java

@@ -929,6 +929,42 @@ public void itHandlesDeferredInNamespaceSecondPass() {
     );
   }
 
+  @Test
+  public void itReconstructsNamespaceForSetTagsAcrossScope() {
+    expectedTemplateInterpreter.assertExpectedOutput(
+      "reconstructs-namespace-for-set-tags-across-scope/test"
+    );
+  }
+
+  @Test
+  public void itReconstructsNamespaceForSetTagsAcrossScopeSecondPass() {
+    localContext.put("deferred", "resolved");
+    expectedTemplateInterpreter.assertExpectedOutput(
+      "reconstructs-namespace-for-set-tags-across-scope/test.expected"
+    );
+    expectedTemplateInterpreter.assertExpectedNonEagerOutput(
+      "reconstructs-namespace-for-set-tags-across-scope/test.expected"
+    );
+  }
+
+  @Test
+  public void itReconstructsNamespaceForSetTagsInForLoop() {
+    expectedTemplateInterpreter.assertExpectedOutput(
+      "reconstructs-namespace-for-set-tags-in-for-loop/test"
+    );
+  }
+
+  @Test
+  public void itReconstructsNamespaceForSetTagsInForLoopSecondPass() {
+    localContext.put("deferred", 2);
+    expectedTemplateInterpreter.assertExpectedOutput(
+      "reconstructs-namespace-for-set-tags-in-for-loop/test.expected"
+    );
+    expectedTemplateInterpreter.assertExpectedNonEagerOutput(
+      "reconstructs-namespace-for-set-tags-in-for-loop/test.expected"
+    );
+  }
+
   @Test
   public void itHandlesClashingNameInMacro() {
     expectedTemplateInterpreter.assertExpectedOutput(

src/test/java/com/hubspot/jinjava/lib/tag/eager/EagerSetTagTest.java

@@ -9,7 +9,9 @@
 import com.hubspot.jinjava.interpret.TemplateError.ErrorReason;
 import com.hubspot.jinjava.lib.tag.SetTagTest;
 import com.hubspot.jinjava.mode.EagerExecutionMode;
+import com.hubspot.jinjava.objects.Namespace;
 import com.hubspot.jinjava.tree.parse.TagToken;
+import java.util.HashMap;
 import java.util.Optional;
 import java.util.stream.Collectors;
 import org.junit.After;
@@ -98,6 +100,63 @@ public void itHandlesMultipleVars() {
       .containsExactlyInAnyOrder("deferred", "range");
   }
 
+  @Test
+  public void itDefersNamespaceRootAsUsedWordForDottedSet() {
+    context.put("ns", new Namespace());
+    context.setDeferredExecutionMode(true);
+    interpreter.render("{% set ns.enabled = deferred %}");
+    Optional<DeferredToken> maybeDeferredToken = context
+      .getDeferredTokens()
+      .stream()
+      .filter(e -> ((TagToken) e.getToken()).getTagName().equals(tag.getName()))
+      .findAny();
+    assertThat(maybeDeferredToken).isPresent();
+    assertThat(maybeDeferredToken.get().getSetDeferredWords())
+      .containsExactly("ns.enabled");
+    assertThat(maybeDeferredToken.get().getUsedDeferredWords()).contains("ns");
+  }
+
+  @Test
+  public void itDefersNamespaceRootAsUsedWordForDottedBlockSet() {
+    context.put("ns", new Namespace());
+    context.setDeferredExecutionMode(true);
+    interpreter.render("{% set ns.enabled %}{{ deferred }}{% endset %}");
+    Optional<DeferredToken> maybeDeferredToken = context
+      .getDeferredTokens()
+      .stream()
+      .filter(e -> e.getToken() instanceof TagToken)
+      .filter(e -> ((TagToken) e.getToken()).getTagName().equals(tag.getName()))
+      .findAny();
+    assertThat(maybeDeferredToken).isPresent();
+    assertThat(maybeDeferredToken.get().getSetDeferredWords())
+      .containsExactly("ns.enabled");
+    assertThat(maybeDeferredToken.get().getUsedDeferredWords()).contains("ns");
+  }
+
+  @Test
+  public void itDoesNotDeferNonNamespaceRootAsUsedWordForDottedSet() {
+    context.put("someMap", new HashMap<String, Object>());
+    context.setDeferredExecutionMode(true);
+    interpreter.render("{% set someMap.field = deferred %}");
+    Optional<DeferredToken> maybeDeferredToken = context
+      .getDeferredTokens()
+      .stream()
+      .filter(e -> ((TagToken) e.getToken()).getTagName().equals(tag.getName()))
+      .findAny();
+    assertThat(maybeDeferredToken).isPresent();
+    assertThat(maybeDeferredToken.get().getUsedDeferredWords()).doesNotContain("someMap");
+  }
+
+  @Test
+  public void itDoesNotThrowWhenNamespaceHoldsUnserializableValue() {
+    Namespace ns = new Namespace();
+    ns.put("obj", new Object());
+    context.put("ns", ns);
+    context.setDeferredExecutionMode(true);
+    interpreter.render("{% set ns.enabled = deferred %}");
+    assertThat(interpreter.getErrors()).isEmpty();
+  }
+
   @Test
   public void itLimitsLength() {
     StringBuilder tooLong = new StringBuilder();

src/test/resources/eager/reconstructs-namespace-for-set-tags-across-scope/test.expected.expected.jinja

@@ -0,0 +1 @@
+resolved

src/test/resources/eager/reconstructs-namespace-for-set-tags-across-scope/test.expected.jinja

@@ -0,0 +1,6 @@
+{% set ns = namespace({'enabled': false} ) %}\
+{% set __macro_setit_1985651457_temp_variable_0__ %}\
+{% set ns.enabled = deferred %}\
+{% endset %}\
+{{ __macro_setit_1985651457_temp_variable_0__ }}
+{{ ns.enabled }}

src/test/resources/eager/reconstructs-namespace-for-set-tags-across-scope/test.jinja

@@ -0,0 +1,4 @@
+{%- set ns = namespace(enabled=false) %}
+{%- macro setit() %}{% set ns.enabled = deferred %}{% endmacro %}
+{{- setit() -}}
+{{ ns.enabled }}

src/test/resources/eager/reconstructs-namespace-for-set-tags-in-for-loop/test.expected.expected.jinja

@@ -0,0 +1 @@
+true

src/test/resources/eager/reconstructs-namespace-for-set-tags-in-for-loop/test.expected.jinja

@@ -0,0 +1,13 @@
+{% set ns = namespace({'found': false} ) %}\
+{% for __ignored__ in [0] %}\
+{% if 1 == deferred %}\
+{% set ns.found = true %}\
+{% endif %}\
+{% if 2 == deferred %}\
+{% set ns.found = true %}\
+{% endif %}\
+{% if 3 == deferred %}\
+{% set ns.found = true %}\
+{% endif %}\
+{% endfor %}
+{{ ns.found }}

src/test/resources/eager/reconstructs-namespace-for-set-tags-in-for-loop/test.jinja

@@ -0,0 +1,5 @@
+{%- set ns = namespace(found=false) %}
+{%- for item in [1, 2, 3] %}
+{%- if item == deferred %}{% set ns.found = true %}{% endif %}
+{%- endfor %}
+{{ ns.found }}