Enable random sampling by day-of-month

This enables random sampling using the day of the month as a seed for
the RNG.  This means that, in principle, we can recreate any failures by
looking up on which day the test failed.  At the same time, we benefit
from wider testing over a period of time.

A default sample size is given individually for each test, and this can
be overridden using a single environment variable
PRC_CALLTESTS_SAMPLE_SIZE.  Hopefully, this provides the level of
flexibility needed.

Author: DavePearce

.github/workflows/gradle-prc-call-tests.yml

@@ -1,7 +1,6 @@
 name: Weekly Precompile Call Tests
 
 on:
-  pull_request:
   schedule:
     - cron: "0 4 * * 1"
   workflow_dispatch:
@@ -24,10 +23,11 @@ jobs:
         uses: ./.github/actions/setup-environment
 
       - name: Run Precompile Call tests
-        run: GOMAXPROCS=1 GOMEMLIMIT=5GiB ./gradlew prcCallTests
+        run: GOMAXPROCS=2 GOMEMLIMIT=5GiB ./gradlew prcCallTests
         env:
           JAVA_OPTS: -Dorg.gradle.daemon=false
-          PRC_CALL_TESTS_PARALLELISM: 24
+          PRC_CALLTESTS_PARALLELISM: 26
+          PRC_CALLTESTS_SAMPLE_SIZE: 1500
           GOCORSET_FLAGS: -vw -b1024 --ansi-escapes=false --report --hir
 
       - name: Upload prc calls test report

arithmetization/src/test/java/net/consensys/linea/zktracer/instructionprocessing/callTests/Utilities.java

@@ -18,7 +18,10 @@
 import static net.consensys.linea.zktracer.Trace.WORD_SIZE;
 import static net.consensys.linea.zktracer.opcode.OpCode.*;
 
+import java.util.Calendar;
+import java.util.Collections;
 import java.util.List;
+import java.util.Random;
 
 import net.consensys.linea.UnitTestWatcher;
 import net.consensys.linea.testing.BytecodeCompiler;
@@ -304,4 +307,27 @@ public static void pushSeveral(BytecodeCompiler program, int... values) {
       program.push(value);
     }
   }
+
+  /**
+   * Sample exactly n items at random from a given input list. If that list has fewer than n items,
+   * then the list is returned unchanged. The Random Number Generated (RNG) is seeded with the
+   * day-of-the-month. The idea here is that we benefit from different seeds (i.e. by testing
+   * different inputs), but should a failure occur we can (in principle) recreate it (provided we
+   * know what day of the month it failed on).
+   *
+   * @param n Number of items to sample
+   * @param items Source of items to sample from
+   * @param <T>
+   * @return
+   */
+  public static <T> List<T> randomSampleByDayOfMonth(int n, List<T> items) {
+    // Determine day of month
+    int dayOfMonth = Calendar.getInstance().get(Calendar.DAY_OF_MONTH);
+    // See rng with day of month.
+    Random rng = new Random(dayOfMonth);
+    // Randomly shuffle the items
+    Collections.shuffle(items, rng);
+    //
+    return items.subList(0, n);
+  }
 }

arithmetization/src/test/java/net/consensys/linea/zktracer/instructionprocessing/callTests/prc/ecadd/ParameterGeneration.java

@@ -19,7 +19,6 @@
 
 import java.util.ArrayList;
 import java.util.List;
-import java.util.stream.Stream;
 
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.GasParameter;
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.ReturnAtParameter;
@@ -52,7 +51,7 @@ public class ParameterGeneration {
    * <p>- <b>ReturnAtParameter</b> the return at parameter to be tested; return data will be written
    * on the aforementioned blackened word in RAM;
    */
-  public static Stream<Arguments> parameterGeneration() {
+  public static List<Arguments> parameterGeneration() {
     List<OpCode> CallOpCodes = List.of(CALL, CALLCODE, DELEGATECALL, STATICCALL);
     List<GasParameter> GasParameters =
         List.of(GasParameter.ZERO, GasParameter.COST_MO, GasParameter.COST, GasParameter.PLENTY);
@@ -79,6 +78,6 @@ public static Stream<Arguments> parameterGeneration() {
         }
       }
     }
-    return argumentsList.stream();
+    return argumentsList;
   }
 }

arithmetization/src/test/java/net/consensys/linea/zktracer/instructionprocessing/callTests/prc/ecadd/Tests.java

@@ -14,6 +14,7 @@
  */
 package net.consensys.linea.zktracer.instructionprocessing.callTests.prc.ecadd;
 
+import static net.consensys.linea.zktracer.instructionprocessing.callTests.Utilities.randomSampleByDayOfMonth;
 import static net.consensys.linea.zktracer.instructionprocessing.callTests.prc.CodeExecutionMethods.*;
 import static net.consensys.linea.zktracer.instructionprocessing.callTests.prc.GasParameter.COST_MO;
 import static net.consensys.linea.zktracer.instructionprocessing.callTests.prc.ecadd.MemoryContents.WELL_FORMED_POINTS;
@@ -24,14 +25,20 @@
 import net.consensys.linea.testing.BytecodeCompiler;
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.ReturnAtParameter;
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.framework.PrecompileCallTests;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Tag;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.provider.Arguments;
 
-//@Disabled
 @Tag("prc-calltests")
 public class Tests extends PrecompileCallTests<CallParameters> {
+  // Set sample size with potential for override.
+  private static final int ECADD_SAMPLE_SIZE =
+      Integer.parseInt(System.getenv().getOrDefault("PRC_CALLTESTS_SAMPLE_SIZE", "500"));
+
+  public static Stream<Arguments> parameterGeneration() {
+    return randomSampleByDayOfMonth(ECADD_SAMPLE_SIZE, ParameterGeneration.parameterGeneration())
+        .stream();
+  }
 
   /** Non-parametric test to make sure things are working as expected. */
   @Test
@@ -48,8 +55,4 @@ public void singleMessageCallTransactionTest() {
     BytecodeCompiler rootCode = params.customPrecompileCallsSeparatedByReturnDataWipingOperation();
     runMessageCallTransactionWithProvidedCodeAsRootCode(rootCode);
   }
-
-  public static Stream<Arguments> parameterGeneration() {
-    return ParameterGeneration.parameterGeneration();
-  }
 }

arithmetization/src/test/java/net/consensys/linea/zktracer/instructionprocessing/callTests/prc/ecmul/ParameterGeneration.java

@@ -20,7 +20,6 @@
 
 import java.util.ArrayList;
 import java.util.List;
-import java.util.stream.Stream;
 
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.GasParameter;
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.ReturnAtParameter;
@@ -29,7 +28,7 @@
 
 public class ParameterGeneration {
 
-  public static Stream<Arguments> parameterGeneration() {
+  public static List<Arguments> parameterGeneration() {
     List<OpCode> CallOpCodes = List.of(CALL, CALLCODE, DELEGATECALL, STATICCALL);
     List<GasParameter> GasParameters = List.of(ZERO, COST_MO, COST, PLENTY);
     List<ReturnAtParameter> ReturnAtParameters =
@@ -55,6 +54,6 @@ public static Stream<Arguments> parameterGeneration() {
         }
       }
     }
-    return argumentsList.stream();
+    return argumentsList;
   }
 }

arithmetization/src/test/java/net/consensys/linea/zktracer/instructionprocessing/callTests/prc/ecmul/Tests.java

@@ -26,17 +26,19 @@
 import net.consensys.linea.testing.BytecodeCompiler;
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.ReturnAtParameter;
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.framework.PrecompileCallTests;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Tag;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.provider.Arguments;
 
-@Disabled
 @Tag("prc-calltests")
 public class Tests extends PrecompileCallTests<CallParameters> {
+  // Set sample size with potential for override.
+  private static final int ECMUL_SAMPLE_SIZE =
+      Integer.parseInt(System.getenv().getOrDefault("PRC_CALLTESTS_SAMPLE_SIZE", "500"));
 
   public static Stream<Arguments> parameterGeneration() {
-    return ParameterGeneration.parameterGeneration();
+    return randomSampleByDayOfMonth(ECMUL_SAMPLE_SIZE, ParameterGeneration.parameterGeneration())
+        .stream();
   }
 
   /** Non-parametric test to make sure things are working as expected. */

arithmetization/src/test/java/net/consensys/linea/zktracer/instructionprocessing/callTests/prc/ecpairing/ParameterGeneration.java

@@ -23,7 +23,6 @@
 
 import java.util.ArrayList;
 import java.util.List;
-import java.util.stream.Stream;
 
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.GasParameter;
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.ReturnAtParameter;
@@ -32,7 +31,7 @@
 
 public class ParameterGeneration {
 
-  public static Stream<Arguments> parameterGeneration() {
+  public static List<Arguments> parameterGeneration() {
     List<OpCode> CallOpCodes = List.of(CALL, STATICCALL);
     List<GasParameter> GasParameters = List.of(COST_MO, COST, PLENTY);
     List<ReturnAtParameter> ReturnAtParameters = List.of(PARTIAL, FULL);
@@ -88,6 +87,6 @@ public static Stream<Arguments> parameterGeneration() {
         }
       }
     }
-    return argumentsList.stream();
+    return argumentsList;
   }
 }

arithmetization/src/test/java/net/consensys/linea/zktracer/instructionprocessing/callTests/prc/ecpairing/Tests.java

@@ -14,19 +14,24 @@
  */
 package net.consensys.linea.zktracer.instructionprocessing.callTests.prc.ecpairing;
 
+import static net.consensys.linea.zktracer.instructionprocessing.callTests.Utilities.randomSampleByDayOfMonth;
+
 import java.util.stream.Stream;
 
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.framework.PrecompileCallTests;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Tag;
 import org.junit.jupiter.params.provider.Arguments;
 
-@Disabled
 @Tag("prc-calltests")
 public class Tests extends PrecompileCallTests<CallParameters> {
+  // Set sample size with potential for override.
+  private static final int ECPAIRING_SAMPLE_SIZE =
+      Integer.parseInt(System.getenv().getOrDefault("PRC_CALLTESTS_SAMPLE_SIZE", "500"));
 
   public static Stream<Arguments> parameterGeneration() {
-    return ParameterGeneration.parameterGeneration();
+    return randomSampleByDayOfMonth(
+        ECPAIRING_SAMPLE_SIZE, ParameterGeneration.parameterGeneration())
+        .stream();
   }
 
   // @Test

arithmetization/src/test/java/net/consensys/linea/zktracer/instructionprocessing/callTests/prc/ecrecover/ParameterGeneration.java

@@ -19,7 +19,6 @@
 
 import java.util.ArrayList;
 import java.util.List;
-import java.util.stream.Stream;
 
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.GasParameter;
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.ReturnAtParameter;
@@ -28,7 +27,7 @@
 
 public class ParameterGeneration {
 
-  public static Stream<Arguments> parameterGeneration() {
+  public static List<Arguments> parameterGeneration() {
     List<OpCode> CallOpCodes = List.of(CALL, CALLCODE, DELEGATECALL, STATICCALL);
     List<GasParameter> GasParameters = List.of(ZERO, COST_MO, COST, PLENTY);
     List<ReturnAtParameter> ReturnAtParameters =
@@ -54,6 +53,6 @@ public static Stream<Arguments> parameterGeneration() {
         }
       }
     }
-    return argumentsList.stream();
+    return argumentsList;
   }
 }

arithmetization/src/test/java/net/consensys/linea/zktracer/instructionprocessing/callTests/prc/ecrecover/Tests.java

@@ -14,17 +14,23 @@
  */
 package net.consensys.linea.zktracer.instructionprocessing.callTests.prc.ecrecover;
 
+import static net.consensys.linea.zktracer.instructionprocessing.callTests.Utilities.randomSampleByDayOfMonth;
+
 import java.util.stream.Stream;
 
 import net.consensys.linea.zktracer.instructionprocessing.callTests.prc.framework.PrecompileCallTests;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Tag;
 import org.junit.jupiter.params.provider.Arguments;
 
-@Disabled
 @Tag("prc-calltests")
 public class Tests extends PrecompileCallTests<CallParameters> {
+  // Set sample size with potential for override.
+  private static int ECRECOVER_SAMPLE_SIZE =
+      Integer.parseInt(System.getenv().getOrDefault("PRC_CALLTESTS_SAMPLE_SIZE", "500"));
+
   public static Stream<Arguments> parameterGeneration() {
-    return ParameterGeneration.parameterGeneration();
+    return randomSampleByDayOfMonth(
+        ECRECOVER_SAMPLE_SIZE, ParameterGeneration.parameterGeneration())
+        .stream();
   }
 }