fix(632): Make the theshold code more testable and allow limit of 0 surviving mutants

pitest-command-line/src/main/java/org/pitest/mutationtest/commandline/MutationCoverageReport.java

@@ -14,17 +14,15 @@
  */
 package org.pitest.mutationtest.commandline;
 
-import java.util.HashMap;
-
-import org.pitest.coverage.CoverageSummary;
 import org.pitest.mutationtest.config.PluginServices;
 import org.pitest.mutationtest.config.ReportOptions;
-import org.pitest.mutationtest.statistics.MutationStatistics;
 import org.pitest.mutationtest.tooling.AnalysisResult;
 import org.pitest.mutationtest.tooling.CombinedStatistics;
 import org.pitest.mutationtest.tooling.EntryPoint;
 import org.pitest.util.Unchecked;
 
+import java.util.HashMap;
+
 /**
  * Entry point for command line interface
  */
@@ -35,6 +33,7 @@ public static void main(final String[] args) {
     final PluginServices plugins = PluginServices.makeForContextLoader();
     final OptionsParser parser = new OptionsParser(new PluginFilter(plugins));
     final ParseResult pr = parser.parse(args);
+    final ThresholdValidator thresholdValidator = new ThresholdValidator();
 
     if (!pr.isOk()) {
       parser.printHelp();
@@ -44,42 +43,16 @@ public static void main(final String[] args) {
 
       final CombinedStatistics stats = runReport(data, plugins);
 
-      throwErrorIfScoreBelowCoverageThreshold(stats.getCoverageSummary(),
+      thresholdValidator.throwErrorIfScoreBelowCoverageThreshold(stats.getCoverageSummary(),
           data.getCoverageThreshold());
-      throwErrorIfScoreBelowMutationThreshold(stats.getMutationStatistics(),
+      thresholdValidator.throwErrorIfScoreBelowMutationThreshold(stats.getMutationStatistics(),
           data.getMutationThreshold());
-      throwErrorIfMoreThanMaxSuvivingMutants(stats.getMutationStatistics(), data.getMaximumAllowedSurvivors());
+      thresholdValidator.throwErrorIfMoreThanMaxSurvivingMutants(stats.getMutationStatistics(),
+          data.getMaximumAllowedSurvivors());
     }
 
   }
 
-  private static void throwErrorIfScoreBelowCoverageThreshold(
-      CoverageSummary stats, int threshold) {
-    if ((threshold != 0) && (stats.getCoverage() < threshold)) {
-      throw new RuntimeException("Line coverage of " + stats.getCoverage()
-          + " is below threshold of " + threshold);
-    }
-  }
-
-  private static void throwErrorIfScoreBelowMutationThreshold(
-      final MutationStatistics stats, final int threshold) {
-    if ((threshold != 0) && (stats.getPercentageDetected() < threshold)) {
-      throw new RuntimeException("Mutation score of "
-          + stats.getPercentageDetected() + " is below threshold of "
-          + threshold);
-    }
-  }
-
-  private static void throwErrorIfMoreThanMaxSuvivingMutants(
-      final MutationStatistics stats, final long threshold) {
-    if ((threshold > 0)
-        && (stats.getTotalSurvivingMutations() > threshold)) {
-      throw new RuntimeException("Had "
-          + stats.getTotalSurvivingMutations() + " surviving mutants, but only "
-          + threshold + " survivors allowed");
-    }
-  }
-
   private static CombinedStatistics runReport(ReportOptions data,
       PluginServices plugins) {
 

pitest-command-line/src/main/java/org/pitest/mutationtest/commandline/ThresholdValidator.java

@@ -0,0 +1,34 @@
+package org.pitest.mutationtest.commandline;
+
+import org.pitest.coverage.CoverageSummary;
+import org.pitest.mutationtest.statistics.MutationStatistics;
+
+public class ThresholdValidator {
+
+  public void throwErrorIfScoreBelowCoverageThreshold(CoverageSummary stats, int threshold) {
+    if ((threshold != 0) && (stats.getCoverage() < threshold)) {
+      throw new RuntimeException("Line coverage of " + stats.getCoverage()
+                    + " is below threshold of " + threshold);
+    }
+  }
+
+  public void throwErrorIfScoreBelowMutationThreshold(
+          final MutationStatistics stats, final int threshold) {
+    if ((threshold != 0) && (stats.getPercentageDetected() < threshold)) {
+      throw new RuntimeException("Mutation score of "
+              + stats.getPercentageDetected() + " is below threshold of "
+              + threshold);
+    }
+  }
+
+  public void throwErrorIfMoreThanMaxSurvivingMutants(
+          final MutationStatistics stats, final long threshold) {
+    if ((threshold >= 0)
+            && (stats.getTotalSurvivingMutations() > threshold)) {
+      throw new RuntimeException("Had "
+              + stats.getTotalSurvivingMutations() + " surviving mutants, but only "
+              + threshold + " survivors allowed");
+    }
+  }
+
+}

pitest-command-line/src/test/java/org/pitest/mutationtest/commandline/ThresholdValidatorTest.java

@@ -0,0 +1,168 @@
+package org.pitest.mutationtest.commandline;
+
+import org.junit.Test;
+import org.pitest.coverage.CoverageSummary;
+import org.pitest.mutationtest.statistics.MutationStatistics;
+import org.pitest.mutationtest.statistics.Score;
+
+import java.util.Collections;
+
+import static org.junit.Assert.fail;
+
+public class ThresholdValidatorTest {
+
+  private final ThresholdValidator testee = new ThresholdValidator();
+
+  @Test
+  public void shouldThrowErrorIfScoreBelowCoverageThreshold() throws Exception {
+    final CoverageSummary coverageSummary = new CoverageSummary(1, 0);
+
+    try {
+      this.testee.throwErrorIfScoreBelowCoverageThreshold(coverageSummary, 1);
+      fail();
+    } catch (RuntimeException e) {
+    }
+  }
+
+  @Test
+  public void shouldNotThrowErrorIfScoreBelowCoverageThresholdZero() throws Exception {
+    final CoverageSummary coverageSummary = new CoverageSummary(1, 0);
+
+    try {
+      this.testee.throwErrorIfScoreBelowCoverageThreshold(coverageSummary, 0);
+    } catch (RuntimeException e) {
+      fail();
+    }
+  }
+
+  @Test
+  public void shouldNotThrowErrorIfScoreAboveCoverage() throws Exception {
+    final CoverageSummary coverageSummary = new CoverageSummary(2, 1);
+
+    try {
+      this.testee.throwErrorIfScoreBelowCoverageThreshold(coverageSummary, 49);
+    } catch (RuntimeException e) {
+      fail();
+    }
+  }
+
+  @Test
+  public void shouldNotThrowErrorIfScoreEqualToCoverage() throws Exception {
+    final CoverageSummary coverageSummary = new CoverageSummary(2, 1);
+
+    try {
+      this.testee.throwErrorIfScoreBelowCoverageThreshold(coverageSummary, 50);
+    } catch (RuntimeException e) {
+      fail();
+    }
+  }
+
+  @Test
+  public void shouldThrowErrorIfScoreBelowMutationThreshold() throws Exception {
+    final Iterable<Score> scores = Collections.emptyList();
+    final MutationStatistics mutationStatistics = new MutationStatistics(scores, 1, 0, 0);
+
+    try {
+      this.testee.throwErrorIfScoreBelowMutationThreshold(mutationStatistics, 1);
+      fail();
+    } catch (RuntimeException e) {
+    }
+  }
+
+  @Test
+  public void shouldNotThrowErrorIfScoreBelowMutationThresholdZero() throws Exception {
+    final Iterable<Score> scores = Collections.emptyList();
+    final MutationStatistics mutationStatistics = new MutationStatistics(scores, 1, 0, 0);
+
+    try {
+      this.testee.throwErrorIfScoreBelowMutationThreshold(mutationStatistics, 0);
+    } catch (RuntimeException e) {
+      fail();
+    }
+  }
+
+  @Test
+  public void shouldNotThrowErrorIfScoreAboveMutationThreshold() throws Exception {
+    final Iterable<Score> scores = Collections.emptyList();
+    final MutationStatistics mutationStatistics = new MutationStatistics(scores, 4, 1, 0);
+
+    try {
+      this.testee.throwErrorIfScoreBelowMutationThreshold(mutationStatistics, 24);
+    } catch (RuntimeException e) {
+      fail();
+    }
+  }
+
+  @Test
+  public void shouldNotThrowErrorIfScoreEqualToMutationThreshold() throws Exception {
+    final Iterable<Score> scores = Collections.emptyList();
+    final MutationStatistics mutationStatistics = new MutationStatistics(scores, 4, 1, 0);
+
+    try {
+      this.testee.throwErrorIfScoreBelowMutationThreshold(mutationStatistics, 25);
+    } catch (RuntimeException e) {
+      fail();
+    }
+  }
+
+  @Test
+  public void shouldThrowErrorIfMoreThanMaxSurvivingMutantsThresholdZero() throws Exception {
+    final Iterable<Score> scores = Collections.emptyList();
+    final MutationStatistics mutationStatistics = new MutationStatistics(scores, 1, 0, 0);
+
+    try {
+      this.testee.throwErrorIfMoreThanMaxSurvivingMutants(mutationStatistics, 0);
+      fail();
+    } catch (RuntimeException e) {
+    }
+  }
+
+  @Test
+  public void shouldNotThrowErrorIfEqualToMaxSurvivingMutantsThresholdZero() throws Exception {
+    final Iterable<Score> scores = Collections.emptyList();
+    final MutationStatistics mutationStatistics = new MutationStatistics(scores, 1, 0, 0);
+
+    try {
+      this.testee.throwErrorIfMoreThanMaxSurvivingMutants(mutationStatistics, 1);
+    } catch (RuntimeException e) {
+      fail();
+    }
+  }
+
+  @Test
+  public void shouldNotThrowErrorIfLessThanMaxSurvivingMutantsThresholdOne() throws Exception {
+    final Iterable<Score> scores = Collections.emptyList();
+    final MutationStatistics mutationStatistics = new MutationStatistics(scores, 1, 1, 0);
+
+    try {
+      this.testee.throwErrorIfMoreThanMaxSurvivingMutants(mutationStatistics, 1);
+    } catch (RuntimeException e) {
+      fail();
+    }
+  }
+
+  @Test
+  public void shouldNotThrowErrorIfEqualToMaxSurvivingMutantsThresholdOne() throws Exception {
+    final Iterable<Score> scores = Collections.emptyList();
+    final MutationStatistics mutationStatistics = new MutationStatistics(scores, 2, 1, 0);
+
+    try {
+      this.testee.throwErrorIfMoreThanMaxSurvivingMutants(mutationStatistics, 1);
+    } catch (RuntimeException e) {
+      fail();
+    }
+  }
+
+  @Test
+  public void shouldThrowErrorIfMoreThanMaxSurvivingMutantsThresholdOne() throws Exception {
+    final Iterable<Score> scores = Collections.emptyList();
+    final MutationStatistics mutationStatistics = new MutationStatistics(scores, 1, 0, 0);
+
+    try {
+      this.testee.throwErrorIfMoreThanMaxSurvivingMutants(mutationStatistics, 1);
+    } catch (RuntimeException e) {
+      fail();
+    }
+  }
+
+}