Extract WhileLoopAnalysis for issue #22

Author: Zomis

src/main/groovy/net/zomis/brainf/analyze/Brainalyze.groovy

@@ -101,11 +101,6 @@ class Brainalyze implements BrainfuckListener {
         println 'Code instructions per command'
         printCommands(codeCommands)
         println()
-        println 'While loops analysis'
-        whileLoopCounts.sorted().forEach({entry ->
-            println "$entry.key $entry.value"
-        })
-        println()
         if (this.memoryIndexBelowZero) {
             println 'WARNING: Memory index goes below zero'
         }
@@ -170,39 +165,12 @@ class Brainalyze implements BrainfuckListener {
         if (command == BrainFCommand.WRITE) {
             cell.prints.add(codeIndex)
         }
-
-        if (command == BrainFCommand.WHILE) {
-            IndexCounter counter = whileLoopCounts.getOrCreate(runner.code.commandIndex)
-            int current = runner.memory.value
-            if (current == 0) {
-                counter.add(0)
-            } else {
-                whileLoopCounts.begin(counter)
-                cell.whileLoopStart.add(codeIndex)
-            }
-        }
-
-        if (command == BrainFCommand.END_WHILE) {
-            whileLoopCounts.recent().increase()
-            int startIndex = whileLoopCounts.recent().forIndex
-            int current = runner.memory.value
-            if (current == 0) {
-                whileLoopCounts.finishLast()
-                cell.whileLoopEnd.add(startIndex)
-            } else {
-                cell.whileLoopContinue.add(startIndex)
-            }
-        }
     }
 
     @Override
     void afterPerform(BrainfuckRunner runner, BrainfuckCommand command) {
     }
 
-    IndexCounters getWhileLoopCounts() {
-        return this.whileLoopCounts
-    }
-
     int getActionsForCommand(BrainFCommand command) {
         this.actionsPerCommand[command.ordinal()]
     }

src/main/groovy/net/zomis/brainf/analyze/MemoryCell.groovy

@@ -20,10 +20,6 @@ class MemoryCell {
 
     private final Map<Class<?>, Object> analysis = [:]
 
-    IndexCounter whileLoopStart = new IndexCounter('loop-begin')
-    IndexCounter whileLoopContinue = new IndexCounter('loop-continue')
-    IndexCounter whileLoopEnd = new IndexCounter('loop-end')
-
     MemoryCell(int index) {
         this.index = index
     }
@@ -34,6 +30,9 @@ class MemoryCell {
             obj = analyzer.createMemoryData()
             analysis.put(clazz, obj)
         }
+        if (!obj) {
+            throw new IllegalStateException("Analyzer $analyzer does not create a memory data object of $clazz")
+        }
         return (T) obj;
     }
 
@@ -61,8 +60,7 @@ class MemoryCell {
         Stream<CellTagger> taggers = this.analysis.values().stream()
             .filter({it instanceof CellTagger})
             .map({it as CellTagger})
-        Stream<CellTagger> oldTaggers = Stream.of(prints, userInputs,
-                whileLoopStart, whileLoopContinue, whileLoopEnd)
+        Stream<CellTagger> oldTaggers = Stream.of(prints, userInputs)
         Stream.concat(taggers, oldTaggers)
             .flatMap({it.tags(loopNames)})
             .sorted()

src/main/groovy/net/zomis/brainf/analyze/analyzers/WhileLoopAnalysis.groovy

@@ -0,0 +1,77 @@
+package net.zomis.brainf.analyze.analyzers
+
+import net.zomis.brainf.analyze.BrainfuckAnalyzer
+import net.zomis.brainf.analyze.CellTagger
+import net.zomis.brainf.analyze.IndexCounter
+import net.zomis.brainf.analyze.IndexCounters
+import net.zomis.brainf.analyze.MemoryCell
+import net.zomis.brainf.model.BrainfuckCommand
+import net.zomis.brainf.model.BrainfuckRunner
+import net.zomis.brainf.model.classic.BrainFCommand
+
+import java.util.function.Function
+import java.util.stream.Stream
+
+class WhileLoopAnalysis implements BrainfuckAnalyzer {
+
+    public static class CellLoops implements CellTagger {
+        IndexCounter whileLoopStart = new IndexCounter('loop-begin')
+        IndexCounter whileLoopContinue = new IndexCounter('loop-continue')
+        IndexCounter whileLoopEnd = new IndexCounter('loop-end')
+
+        @Override
+        Stream<String> tags(Function<Integer, String> indexToStringFunction) {
+            Stream.of(whileLoopStart, whileLoopContinue, whileLoopEnd)
+                .flatMap({it.tags(indexToStringFunction)})
+        }
+
+        String toString() { 'CellLoops ' }
+    }
+
+    private final IndexCounters whileLoopCounts = new IndexCounters()
+
+    IndexCounters getWhileLoopCounts() {
+        return this.whileLoopCounts
+    }
+
+    @Override
+    Object createMemoryData() {
+        return new CellLoops()
+    }
+
+    @Override
+    void print() {
+        println()
+        println 'While loops analysis'
+        whileLoopCounts.sorted().forEach({entry ->
+            println "$entry.key $entry.value"
+        })
+    }
+
+    @Override
+    void beforePerform(MemoryCell cell, BrainfuckRunner runner, BrainfuckCommand command) {
+        int codeIndex = runner.code.commandIndex
+        if (command == BrainFCommand.WHILE) {
+            IndexCounter counter = whileLoopCounts.getOrCreate(runner.code.commandIndex)
+            int current = runner.memory.value
+            if (current == 0) {
+                counter.add(0)
+            } else {
+                whileLoopCounts.begin(counter)
+                cell.data(this, CellLoops).whileLoopStart.add(codeIndex)
+            }
+        }
+
+        if (command == BrainFCommand.END_WHILE) {
+            whileLoopCounts.recent().increase()
+            int startIndex = whileLoopCounts.recent().forIndex
+            int current = runner.memory.value
+            if (current == 0) {
+                whileLoopCounts.finishLast()
+                cell.data(this, CellLoops).whileLoopEnd.add(startIndex)
+            } else {
+                cell.data(this, CellLoops).whileLoopContinue.add(startIndex)
+            }
+        }
+    }
+}

src/test/groovy/net/zomis/brainf/BrainTest.groovy

@@ -4,6 +4,7 @@ import net.zomis.brainf.analyze.IndexCounters
 import net.zomis.brainf.analyze.MemoryCell
 import net.zomis.brainf.analyze.analyzers.MemoryValues
 import net.zomis.brainf.analyze.analyzers.ReadWriteAnalysis
+import net.zomis.brainf.analyze.analyzers.WhileLoopAnalysis
 import net.zomis.brainf.model.BrainF
 import net.zomis.brainf.model.classic.BrainFCommand
 import net.zomis.brainf.model.BrainfuckMemory
@@ -50,7 +51,7 @@ public class BrainTest extends BrainfuckTest {
         ]
         '''
         source.addCommands(commands)
-        analyze()
+        analyze(new WhileLoopAnalysis())
         analyze.print()
         println context.getLoopNames()
         cellTagsContains(analyze.cell(0), 'before')
@@ -89,8 +90,8 @@ public class BrainTest extends BrainfuckTest {
     @Test
     public void analyzeLoops() {
         source.addCommands("++[ > +++++[>+>+++<<-]>[>+<-]<[+-+-]> +++ << -]");
-        analyze()
-        IndexCounters counts = analyze.getWhileLoopCounts();
+        analyze(new WhileLoopAnalysis())
+        IndexCounters counts = analyze.get(WhileLoopAnalysis).getWhileLoopCounts()
         assert counts.size() == 4
         assert counts[2] == [2]
         assert counts[11] == [5, 5]
@@ -101,8 +102,8 @@ public class BrainTest extends BrainfuckTest {
     @Test
     public void loopOnce() {
         source.addCommands("+[-]");
-        analyze()
-        IndexCounters counts = analyze.getWhileLoopCounts();
+        analyze(new WhileLoopAnalysis())
+        IndexCounters counts = analyze.get(WhileLoopAnalysis).getWhileLoopCounts();
         assert counts.size() == 1
         assert counts[1] == [1]
     }