Modularize rewritePaths and improve query compiler debug logging

slick · Jul 17, 2012 · 1bc6c36 · 1bc6c36
1 parent 05b237e
commit 1bc6c36
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Showing 3 changed files with 26 additions and 11 deletions.
diff --git a/src/main/scala/scala/slick/compiler/QueryCompiler.scala b/src/main/scala/scala/slick/compiler/QueryCompiler.scala
@@ -51,7 +51,7 @@ class QueryCompiler(val phases: Vector[Phase]) extends Logging {
     if(t2 ne tree) {
       state.ast = t2
       logger.debug("After phase "+p.name+":", t2)
-    }
+    } else logger.debug("After phase "+p.name+": (no change)")
     t2
   }
 }
@@ -71,7 +71,9 @@ object QueryCompiler {
     Phase.expandRefs,
     Phase.replaceFieldSymbols,
     // PathRewriter
-    Phase.rewritePaths
+    Phase.rewritePaths,
+    Phase.relabelUnions,
+    Phase.pruneFields
   )
 
   val relationalPhases = Vector(
@@ -113,6 +115,8 @@ object Phase {
   val expandRefs = new ExpandRefs
   val replaceFieldSymbols = new ReplaceFieldSymbols
   val rewritePaths = new RewritePaths
+  val relabelUnions = new RelabelUnions
+  val pruneFields = new PruneFields
   val resolveZipJoins = new ResolveZipJoins
   val convertToComprehensions = new ConvertToComprehensions
   val fuseComprehensions = new FuseComprehensions

diff --git a/src/main/scala/scala/slick/compiler/RewritePaths.scala b/src/main/scala/scala/slick/compiler/RewritePaths.scala
@@ -130,11 +130,7 @@ class RewritePaths extends Phase {
     if(n2 ne n) logger.debug("Expansions removed, ProductNodes rewritten to StructNodes", n2)
     val n3 = replaceRefs(n2)
     if(n3 ne n2) logger.debug("Refs replaced", n3)
-    val n4 = relabelUnions(n3)
-    if(n4 ne n3) logger.debug("Unions relabled", n4)
-    val n5 = prune.repeat(n4)
-    if(n5 ne n4) logger.debug("Pruned", n5)
-    n5
+    n3
   }
 
   def findFieldSymbol(n: Node, path: List[Symbol]): Option[Symbol] = (path, n) match {
@@ -149,17 +145,30 @@ class RewritePaths extends Phase {
     case TableRefExpansion(_, ref, cols) => cols
     case n => n
   }
+}
+
+/** Assign the AnonSymbols of fields from the left side of a Union to the
+  * right side. This ensures that both sides are protected when we prune
+  * unused references pointing to left-side Symbols. */
+class RelabelUnions extends Phase {
+  val name = "relabelUnions"
+
+  def apply(n: Node, state: CompilationState) = relabelUnions(n)
 
-  /** Assign the AnonSymbols of fields from the left side of a Union to the
-    * right side. This ensures that both sides are protected when we prune
-    * unused references pointing to left-side Symbols. */
   def relabelUnions(n: Node): Node = n match {
     case u @ Union(l @ Bind(_, _, Pure(StructNode(ls))), rb @ Bind(_, _, Pure(StructNode(rs))), _, _, _)
-        if ls.size == rs.size =>
+      if ls.size == rs.size =>
       val rs2 = (ls, rs).zipped.map { case ((s, _), (_, n)) => (s, n) }
       u.copy(right = rb.copy(select = Pure(StructNode(rs2)))).nodeMapChildren(relabelUnions)
     case n => n.nodeMapChildren(relabelUnions)
   }
+}
+
+/** Remove unreferenced fields from StructNodes */
+class PruneFields extends Phase {
+  val name = "pruneFields"
+
+  def apply(n: Node, state: CompilationState) = prune.repeat(n)
 
   val prune = new Transformer {
     val refs = new HashSet[Symbol]()

diff --git a/src/test/resources/logback-test.xml b/src/test/resources/logback-test.xml
@@ -20,6 +20,8 @@
     <logger name="scala.slick.compiler.ExpandRefs"                level="${log.qcomp.expandRefs:-inherited}" />
     <logger name="scala.slick.compiler.ReplaceFieldSymbols"       level="${log.qcomp.replaceFieldSymbols:-inherited}" />
     <logger name="scala.slick.compiler.RewritePaths"              level="${log.qcomp.rewritePaths:-inherited}" />
+    <logger name="scala.slick.compiler.RelabelUnions"             level="${log.qcomp.relabelUnions:-inherited}" />
+    <logger name="scala.slick.compiler.PruneFields"               level="${log.qcomp.pruneFields:-inherited}" />
     <logger name="scala.slick.compiler.ResolveZipJoins"           level="${log.qcomp.resolveZipJoins:-inherited}" />
     <logger name="scala.slick.compiler.ConvertToComprehensions"   level="${log.qcomp.convertToComprehensions:-inherited}" />
     <logger name="scala.slick.compiler.FuseComprehensions"        level="${log.qcomp.fuseComprehensions:-inherited}" />