Add macro for generating modified Query instantiations (#1098)

* Add `macros` project

* Add temporary usage of macro

* Retrieve source positions

* upgrade to scala 2.13.4 fixes the expression.end issue in macro

* scalameta macros - not a good idea probably

* more WIP

* more wip

* use wildcard types

* cleanup

* more cleanup

* bring both together, make them both whitebox

* move over to console project

* Return Query in queryInit macro

* Reintroduce query properties

To be removed _after_ they're removed from the query database.

* Reenable deprecation warnings

* Run scalafmt

Co-authored-by: Michael Pollmeier <michael@michaelpollmeier.com>

Author: ursachec

build.sbt

@@ -67,6 +67,7 @@ lazy val cpgvalidator = Projects.cpgvalidator
 lazy val console = Projects.console
 lazy val fuzzyc2cpg = Projects.fuzzyc2cpg
 lazy val fuzzyc2cpgtests = Projects.fuzzyc2cpgtests
+lazy val macros = Projects.macros
 
 ThisBuild/scalacOptions ++= Seq(
   "-deprecation",

console/build.sbt

@@ -3,7 +3,8 @@ name := "console"
 enablePlugins(JavaAppPackaging)
 
 dependsOn(Projects.codepropertygraph,
-          Projects.semanticcpg)
+          Projects.semanticcpg,
+          Projects.macros)
 
 scalacOptions ++= Seq(
   "-deprecation",                      // Emit warning and location for usages of deprecated APIs.
@@ -37,7 +38,8 @@ scalacOptions ++= Seq(
   "-Ywarn-unused:locals",              // Warn if a local definition is unused.
   "-Ywarn-unused:params",              // Warn if a value parameter is unused.
   "-Ywarn-unused:patvars",             // Warn if a variable bound in a pattern is unused.
-  "-Ywarn-unused:privates"             // Warn if a private member is unused.
+  "-Ywarn-unused:privates",             // Warn if a private member is unused.
+  "-Yrangepos"
 )
 
 // would love to reenable, but somehow StorageBackend.scala triggers a strange `[warn] method with a single empty parameter list overrides method without any parameter list` that doesn't make sense to me...

console/src/main/scala/io/shiftleft/console/QueryDatabase.scala

@@ -27,6 +27,7 @@ case class Query(name: String,
                  docEndLine: Int = 0,
                  // intended to be filled by com.lihaoyi.sourcecode.FileName
                  docFileName: String = "",
+                 traversalAsString: String = "",
                  tags: List[String] = List())
 
 class QueryDatabase(defaultArgumentProvider: DefaultArgumentProvider = new DefaultArgumentProvider,

console/src/test/scala/io/shiftleft/console/QueryDatabaseTests.scala

@@ -1,8 +1,11 @@
 package io.shiftleft.console
 
 import io.shiftleft.semanticcpg.language._
+import io.shiftleft.codepropertygraph.Cpg
 import org.scalatest.matchers.should
 import org.scalatest.wordspec.AnyWordSpec
+import overflowdb.traversal.Traversal
+import io.shiftleft.macros.QueryMacros
 
 object TestBundle extends QueryBundle {
   @q def foo(n: Int = 4): Query = Query(
@@ -11,9 +14,7 @@ object TestBundle extends QueryBundle {
     title = "a-title",
     description = s"a-description $n",
     score = 2.0,
-    traversal = { cpg =>
-      cpg.method
-    }
+    traversal = { cpg => cpg.method }
   )
 }
 
@@ -35,5 +36,16 @@ class QueryDatabaseTests extends AnyWordSpec with should.Matchers {
       val queries = qdb.queriesInBundle(testBundle)
       queries.count(_.title == "a-title") shouldBe 1
     }
+
+    "serialize traversal to string" in {
+      val query = QueryMacros.queryInit(
+        "a-name",
+        "an-author",
+        "a-title",
+        "a-description",
+        2.0, { cpg: Cpg => cpg.method }).asInstanceOf[Query]
+      query.title shouldBe "a-title"
+      query.traversalAsString shouldBe "cpg: Cpg => cpg.method"
+    }
   }
 }

macros/build.sbt

@@ -0,0 +1,15 @@
+name := "macros"
+
+enablePlugins(JavaAppPackaging)
+
+dependsOn(Projects.codepropertygraph)
+scalacOptions ++= Seq( "-Yrangepos" )
+
+libraryDependencies ++= Seq(
+  "org.scala-lang" % "scala-reflect" % scalaVersion.value,
+)
+
+publishArtifact in (Test, packageBin) := true
+
+// execute tests in root project so that they work in sbt *and* intellij
+Test / baseDirectory := (ThisBuild / Test / run / baseDirectory).value

macros/src/main/scala/io/shiftleft/macros/Macros.scala

@@ -0,0 +1,44 @@
+package io.shiftleft.macros
+
+import io.shiftleft.codepropertygraph.Cpg
+import io.shiftleft.codepropertygraph.generated.nodes
+import overflowdb.traversal.Traversal
+import scala.language.experimental.macros
+import scala.reflect.macros.whitebox
+
+object QueryMacros {
+
+  def queryInit(name: String,
+                author: String,
+                title: String,
+                description: String,
+                score: Double,
+                traversal: Cpg => Traversal[nodes.StoredNode]): Any = macro queryInitImpl
+
+  def queryInitImpl(c: whitebox.Context)(name: c.Tree,
+                                         author: c.Tree,
+                                         title: c.Tree,
+                                         description: c.Tree,
+                                         score: c.Tree,
+                                         traversal: c.Tree): c.Expr[Any] = {
+    import c.universe._
+    val fileContent = new String(traversal.pos.source.content)
+    val start = traversal.pos.start
+    val end = traversal.pos.end
+    val traversalAsString: String = fileContent.slice(start, end)
+
+    c.Expr[Any](
+      q"""
+        Query(
+          name = $name,
+          author = $author,
+          title = $title,
+          description = $description,
+          score = $score,
+          traversal = $traversal,
+          traversalAsString = $traversalAsString
+        )
+     """
+    )
+  }
+}

project/Projects.scala

@@ -13,4 +13,5 @@ object Projects {
   lazy val console = project.in(file("console"))
   lazy val fuzzyc2cpg = project.in(file("fuzzyc2cpg"))
   lazy val fuzzyc2cpgtests = project.in(file("fuzzyc2cpg-tests"))
+  lazy val macros = project.in(file("macros"))
 }