Internal Changes

testing/src/main/java/dev/cel/testing/testrunner/CelCoverageIndex.java

@@ -18,6 +18,7 @@
 
 import com.google.auto.value.AutoValue;
 import com.google.common.collect.ImmutableList;
+import com.google.common.io.Files;
 import com.google.errorprone.annotations.CanIgnoreReturnValue;
 import javax.annotation.concurrent.ThreadSafe;
 import dev.cel.common.CelAbstractSyntaxTree;
@@ -28,6 +29,8 @@
 import dev.cel.common.types.CelKind;
 import dev.cel.parser.CelUnparserVisitor;
 import dev.cel.runtime.CelEvaluationListener;
+import java.io.File;
+import java.io.IOException;
 import java.io.UnsupportedEncodingException;
 import java.net.URLEncoder;
 import java.util.Map;
@@ -170,6 +173,7 @@ public CoverageReport generateCoverageReport() {
         dotGraphBuilder);
     dotGraphBuilder.append("}");
     String dotGraph = dotGraphBuilder.toString();
+
     CoverageReport report = reportBuilder.setDotGraph(dotGraph).build();
     logger.info("CEL Expression: " + report.celExpression());
     logger.info("Nodes: " + report.nodes());
@@ -180,6 +184,8 @@ public CoverageReport generateCoverageReport() {
     logger.info("Unencountered Branches: \n" + String.join("\n",
     report.unencounteredBranches()));
     logger.info("Dot Graph: " + report.dotGraph());
+
+    writeDotGraphToArtifact(dotGraph);
     return report;
   }
 
@@ -392,4 +398,21 @@ private String escapeSpecialCharacters(String exprText) {
         .replace("{", "\\{")
         .replace("}", "\\}");
   }
+
+  private void writeDotGraphToArtifact(String dotGraph) {
+    String testOutputsDir = System.getenv("TEST_UNDECLARED_OUTPUTS_DIR");
+    if (testOutputsDir == null) {
+      // Only for non-bazel/blaze users, we write to a subdirectory under the cwd.
+      testOutputsDir = "cel_artifacts";
+    }
+    File outputDir = new File(testOutputsDir, "cel_test_coverage");
+    if (!outputDir.exists()) {
+      outputDir.mkdirs();
+    }
+    try {
+      Files.asCharSink(new File(outputDir, "coverage_graph.txt"), UTF_8).write(dotGraph);
+    } catch (IOException e) {
+      throw new IllegalStateException(e);
+    }
+  }
 }

testing/src/test/java/dev/cel/testing/testrunner/CelCoverageIndexTest.java

@@ -14,8 +14,10 @@
 package dev.cel.testing.testrunner;
 
 import static com.google.common.truth.Truth.assertThat;
+import static java.nio.charset.StandardCharsets.UTF_8;
 
 import com.google.common.collect.ImmutableMap;
+import com.google.common.io.Files;
 import dev.cel.bundle.Cel;
 import dev.cel.bundle.CelFactory;
 import dev.cel.common.CelAbstractSyntaxTree;
@@ -27,6 +29,7 @@
 import dev.cel.runtime.CelEvaluationListener;
 import dev.cel.runtime.CelRuntime;
 import dev.cel.testing.testrunner.CelCoverageIndex.CoverageReport;
+import java.io.File;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -125,4 +128,32 @@ public void getCoverageReport_comprehension_generatesDotGraph() throws Exception
         .contains("label=\"{<1> exprID: 16 | <2> LoopStep} | <3> @result && i % 2 != 0\"");
     assertThat(report.dotGraph()).contains("label=\"{<1> exprID: 17 | <2> Result} | <3> @result\"");
   }
+
+  @Test
+  public void getCoverageReport_fullCoverage_writesToUndeclaredOutputs() throws Exception {
+    // Setup for a more complex graph to write.
+    cel = CelFactory.standardCelBuilder().build();
+    CelCompiler compiler =
+        cel.toCompilerBuilder()
+            .setOptions(CelOptions.newBuilder().populateMacroCalls(true).build())
+            .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
+            .addLibraries(CelExtensions.comprehensions())
+            .build();
+    ast = compiler.compile("[1, 2, 3].all(i, i % 2 != 0)").getAst();
+    program = cel.createProgram(ast);
+    CelCoverageIndex coverageIndex = new CelCoverageIndex();
+    coverageIndex.init(ast);
+    CelEvaluationListener listener = coverageIndex.newEvaluationListener();
+    program.trace(ImmutableMap.of(), listener);
+
+    CoverageReport report = coverageIndex.generateCoverageReport();
+
+    String undeclaredOutputsDir = System.getenv("TEST_UNDECLARED_OUTPUTS_DIR");
+    assertThat(undeclaredOutputsDir).isNotNull();
+
+    File outputFile = new File(undeclaredOutputsDir, "cel_test_coverage/coverage_graph.txt");
+
+    String fileContent = Files.asCharSource(outputFile, UTF_8).read();
+    assertThat(fileContent).isEqualTo(report.dotGraph());
+  }
 }