Report command lists more nicely (line breaks between commands); report number of nodes visited during shrinking; other small fixes

7 files changed, 36 insertions, 13 deletions

diff --git a/src/main/java/au/id/zancanaro/javacheck/ShrinkResult.java b/src/main/java/au/id/zancanaro/javacheck/ShrinkResult.java
index 6bf3882..f135cee 100644
--- a/src/main/java/au/id/zancanaro/javacheck/ShrinkResult.java
+++ b/src/main/java/au/id/zancanaro/javacheck/ShrinkResult.java
@@ -5,9 +5,13 @@ import java.util.List;
 public class ShrinkResult {
     public final List<Object> args;
     public final Throwable thrown;
+    public final int depth;
+    public final int visited;
 
-    public ShrinkResult(List<Object> args, Throwable thrown) {
+    public ShrinkResult(List<Object> args, Throwable thrown, int depth, int visited) {
         this.args = args;
         this.thrown = thrown;
+        this.depth = depth;
+        this.visited = visited;
     }
 }
diff --git a/src/main/java/au/id/zancanaro/javacheck/junit/Properties.java b/src/main/java/au/id/zancanaro/javacheck/junit/Properties.java
index c428edc..175cd6c 100644
--- a/src/main/java/au/id/zancanaro/javacheck/junit/Properties.java
+++ b/src/main/java/au/id/zancanaro/javacheck/junit/Properties.java
@@ -116,26 +116,30 @@ public class Properties extends BlockJUnit4ClassRunner {
         private ShrinkResult shrink(ShrinkTree<List<Object>> failed, Throwable originalEx) {
             // this array is a mutable container so the shutdown handler can see the new version
             ShrinkResult[] smallest = new ShrinkResult[]{
-                    new ShrinkResult(failed.getValue(), originalEx)};
+                    new ShrinkResult(failed.getValue(), originalEx, 0, 0)};
 
             Thread shutdownHandler = makeShutdownHandler(smallest, originalEx);
             Runtime.getRuntime().addShutdownHook(shutdownHandler);
 
+            int depth = 0;
+            int visited = 0;
             Set<List<Object>> seenArgs = new HashSet<>();
             Iterator<ShrinkTree<List<Object>>> trees = failed.getChildren().iterator();
             while (trees.hasNext()) {
                 ShrinkTree<List<Object>> tree = trees.next();
                 List<Object> value = tree.getValue();
-                boolean haveSeen = seenArgs.add(Arrays.asList(value));
-                if (haveSeen) {
+                boolean notSeen = seenArgs.add(Arrays.asList(value));
+                if (notSeen) {
+                    visited++;
                     try {
                         runTest(value.toArray());
                     } catch (AssumptionViolatedException ex) {
                         // ignore, because it's not useful
                     } catch (Throwable ex) {
-                        smallest[0] = new ShrinkResult(tree.getValue(), ex);
+                        smallest[0] = new ShrinkResult(tree.getValue(), ex, depth, visited);
                         Iterator<ShrinkTree<List<Object>>> children = tree.getChildren().iterator();
                         if (children.hasNext()) {
+                            depth++;
                             trees = children;
                         } else {
                             break;
diff --git a/src/main/java/au/id/zancanaro/javacheck/junit/PropertyError.java b/src/main/java/au/id/zancanaro/javacheck/junit/PropertyError.java
index 5f89ca8..4f02a56 100644
--- a/src/main/java/au/id/zancanaro/javacheck/junit/PropertyError.java
+++ b/src/main/java/au/id/zancanaro/javacheck/junit/PropertyError.java
@@ -9,12 +9,12 @@ import java.util.List;
 public class PropertyError extends AssertionError {
     public PropertyError(String methodName, long seed, ShrinkResult shrunk) {
         super(shrunk.thrown.getMessage() == null ?
-                String.format("%s(%s)%n\tSeed: %s",
+                String.format("%s(%s)%n\tSeed: %s%n\tVisited: %s; Depth: %s",
                         methodName, joinArgs(shrunk.args),
-                        seed):
-                String.format("%s(%s)%n\tSeed: %s%n%s",
+                        seed, shrunk.visited, shrunk.depth):
+                String.format("%s(%s)%n\tSeed: %s%n\tVisited: %s; Depth: %s%n%s",
                         methodName, joinArgs(shrunk.args),
-                        seed,
+                        seed, shrunk.visited, shrunk.depth,
                         shrunk.thrown.getMessage()));
         initCause(shrunk.thrown);
     }
diff --git a/src/main/java/au/id/zancanaro/javacheck/state/CommandList.java b/src/main/java/au/id/zancanaro/javacheck/state/CommandList.java
index 31fbc12..6dc8976 100644
--- a/src/main/java/au/id/zancanaro/javacheck/state/CommandList.java
+++ b/src/main/java/au/id/zancanaro/javacheck/state/CommandList.java
@@ -11,6 +11,10 @@ public class CommandList<S> {
         this.commands = new ArrayList<>(commands);
     }
 
+    public int size() {
+        return commands.size();
+    }
+
     public CommandResult<S> run(S initialState) {
         Map<Integer, Object> values = new HashMap<>();
         CommandResult<S> result = CommandResult.success(initialState);
@@ -86,9 +90,9 @@ public class CommandList<S> {
         while (iterator.hasNext()) {
             builder.append(iterator.next());
             if (iterator.hasNext()) {
-                builder.append(", ");
+                builder.append(", \n\t");
             }
         }
-        return builder.toString();
+        return "\n\t" + builder.toString();
     }
 }
diff --git a/src/main/java/au/id/zancanaro/javacheck/state/CommandListGenerator.java b/src/main/java/au/id/zancanaro/javacheck/state/CommandListGenerator.java
index c5cda59..0eb1793 100644
--- a/src/main/java/au/id/zancanaro/javacheck/state/CommandListGenerator.java
+++ b/src/main/java/au/id/zancanaro/javacheck/state/CommandListGenerator.java
@@ -3,8 +3,15 @@ package au.id.zancanaro.javacheck.state;
 import au.id.zancanaro.javacheck.Generator;
 import au.id.zancanaro.javacheck.ShrinkTree;
 
+import java.util.Arrays;
 import java.util.Random;
+import java.util.Spliterator;
+import java.util.Spliterators;
 import java.util.function.Function;
+import java.util.function.IntConsumer;
+import java.util.stream.IntStream;
+import java.util.stream.Stream;
+import java.util.stream.StreamSupport;
 
 import static au.id.zancanaro.javacheck.Generator.pure;
 import static au.id.zancanaro.javacheck.Generators.noShrink;
diff --git a/src/main/java/au/id/zancanaro/javacheck/state/CommandValue.java b/src/main/java/au/id/zancanaro/javacheck/state/CommandValue.java
index d2f3419..de0dfc5 100644
--- a/src/main/java/au/id/zancanaro/javacheck/state/CommandValue.java
+++ b/src/main/java/au/id/zancanaro/javacheck/state/CommandValue.java
@@ -46,7 +46,7 @@ public class CommandValue<T> {
 
     @SuppressWarnings("unchecked")
     public T get() {
-        if (values.containsKey(id)) {
+        if (values != null && values.containsKey(id)) {
             return (T) values.get(id);
         } else {
             throw new NoSuchElementException("Concrete values cannot be supplied prior to being calculated");
diff --git a/src/main/java/au/id/zancanaro/javacheck/state/GeneratedCommand.java b/src/main/java/au/id/zancanaro/javacheck/state/GeneratedCommand.java
index 92a90f9..85f6fdd 100644
--- a/src/main/java/au/id/zancanaro/javacheck/state/GeneratedCommand.java
+++ b/src/main/java/au/id/zancanaro/javacheck/state/GeneratedCommand.java
@@ -43,6 +43,10 @@ public class GeneratedCommand<S, A, R> {
 
     @Override
     public String toString() {
-        return "#{" + id + "} = " + command + " <- " + args;
+        if (args == null) {
+            return "#{" + id + "} = " + command;
+        } else {
+            return "#{" + id + "} = " + command + " <- " + args;
+        }
     }
 }