From 2514260b5ff7c1ac3c845f75c9e5fd82915df366 Mon Sep 17 00:00:00 2001
From: breandan <bre@ndan.co>
Date: Tue, 8 Oct 2024 00:33:50 -0400
Subject: [PATCH] test non-emptiness latency for nontrivial intersection

---
 .../kaliningraph/parsing/Grammars.kt          |  1 +
 .../hypergraph/kaliningraph/automata/JFSA.kt  | 12 ++++++----
 .../kaliningraph/automata/WFSATest.kt         | 24 +++++++++++++++++++
 3 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/src/commonTest/kotlin/ai/hypergraph/kaliningraph/parsing/Grammars.kt b/src/commonTest/kotlin/ai/hypergraph/kaliningraph/parsing/Grammars.kt
index 18deb9ec..8e3cc819 100644
--- a/src/commonTest/kotlin/ai/hypergraph/kaliningraph/parsing/Grammars.kt
+++ b/src/commonTest/kotlin/ai/hypergraph/kaliningraph/parsing/Grammars.kt
@@ -25,6 +25,7 @@ object Grammars {
     S -> X | Y | Z
   """.parseCFG().noNonterminalStubs
 
+  val dyck = """S -> ( ) | ( S ) | S S""".parseCFG().noEpsilonOrNonterminalStubs
   val deadSimple = """S -> ( ) | ( S )""".parseCFG().noEpsilonOrNonterminalStubs
   val dsNorm = """
     START -> START START
diff --git a/src/jvmMain/kotlin/ai/hypergraph/kaliningraph/automata/JFSA.kt b/src/jvmMain/kotlin/ai/hypergraph/kaliningraph/automata/JFSA.kt
index d2584e49..8aaacf99 100644
--- a/src/jvmMain/kotlin/ai/hypergraph/kaliningraph/automata/JFSA.kt
+++ b/src/jvmMain/kotlin/ai/hypergraph/kaliningraph/automata/JFSA.kt
@@ -57,7 +57,12 @@ data class FSATrajectory(val traj: List<Σᐩ?>, val lastState: BState, val scor
 
 fun BAutomaton.min(): BAutomaton = minimize(this)
 
-fun PTree.toDFA(minimize: Boolean = false) =
+fun PTree.toDFA(
+  minimize: Boolean = false,
+  unitRule: (String) -> dk.brics.automaton.Automaton = {
+    BAutomaton.makeChar(Random(it.hashCode()).nextInt().toChar())
+  }
+) =
   measureTimedValue {
     BAutomaton.setMinimization(MINIMIZE_BRZOZOWSKI)
     var i = 0
@@ -68,10 +73,7 @@ fun PTree.toDFA(minimize: Boolean = false) =
         else if (i++ % 13 == 0) a.concatenate(b).min() else a.concatenate(b) },
       either = { a, b -> if (a == null) b else if (b == null) a
         else if (j++ % 13 == 0) a.union(b).min() else a.union(b) },
-      unit = { a ->
-        if ("ε" in a.root) null
-        else BAutomaton.makeChar(Random(a.root.hashCode()).nextInt().toChar())
-      }
+      unit = { a -> if ("ε" in a.root) null else unitRule(a.root) }
     )
   }.also { println("Took ${it.duration} to build FSA") }.value
   ?.also { println("Original automata had ${it
diff --git a/src/jvmTest/kotlin/ai/hypergraph/kaliningraph/automata/WFSATest.kt b/src/jvmTest/kotlin/ai/hypergraph/kaliningraph/automata/WFSATest.kt
index ba227d9c..5f243e2a 100644
--- a/src/jvmTest/kotlin/ai/hypergraph/kaliningraph/automata/WFSATest.kt
+++ b/src/jvmTest/kotlin/ai/hypergraph/kaliningraph/automata/WFSATest.kt
@@ -10,6 +10,7 @@ import net.jhoogland.jautomata.*
 import net.jhoogland.jautomata.operations.Concatenation
 import net.jhoogland.jautomata.semirings.RealSemiring
 import java.io.File
+import kotlin.system.measureTimeMillis
 import kotlin.test.*
 import kotlin.time.measureTimedValue
 
@@ -72,6 +73,29 @@ class WFSATest {
     println(BAutomaton.minimize(ag.also { it.determinize() }).toDot())
   }
 
+/*
+./gradlew jvmTest --tests "ai.hypergraph.kaliningraph.automata.WFSATest.testIntersectionNonemptiness"
+*/
+  @Test
+  fun testIntersectionNonemptiness() {
+    val ab = BAutomaton.makeString("(").concatenate(BAutomaton.makeString(")"))
+    val aa = BAutomaton.makeString("(").concatenate(BAutomaton.makeString("("))
+    val ac = BAutomaton.makeString("(")
+    val az = RegExp("(\\(+(\\(+\\)+){3,15}\\)+)+").toAutomaton()
+
+    val ds = Grammars.dyck.startPTree(List(20) { "_" })!!
+      .toDFA(false) { BAutomaton.makeString(it) }!!
+
+    val a = ab.union(aa).union(ac)
+    val ag = a.repeat(19, 25).union(az)
+    println("SA:" + ag.getShortestExample(true))
+    println("SD:" + ds.getShortestExample(true))
+    println("SS:" + ds.intersection(ag).getShortestExample(true))
+
+    measureTimeMillis { println(!ds.intersection(ag).isEmpty) }
+      .also { println("Time: $it ms") }
+  }
+
   /*
   ./gradlew jvmTest --tests "ai.hypergraph.kaliningraph.automata.WFSATest.testPTreeVsWFSA"
   */