Merge pull request #96 from OndrejSpanel/pr-modify-tuple

Tuple modification fails with Scala 3
softwaremill · Aug 31, 2022 · a546896 · a546896
2 parents 50592c5 + 98da9f7
commit a546896
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Showing 2 changed files with 43 additions and 8 deletions.
diff --git a/quicklens/src/main/scala-3/com/softwaremill/quicklens/QuicklensMacros.scala b/quicklens/src/main/scala-3/com/softwaremill/quicklens/QuicklensMacros.scala
@@ -54,6 +54,9 @@ object QuicklensMacros {
     def unsupportedShapeInfo(tree: Tree) =
       s"Unsupported path element. Path must have shape: _.field1.field2.each.field3.(...), got: ${tree.show}"
 
+    def noSuchMember(term: Term, name: String) =
+      s"${term.tpe} has no member named $name"
+
     def methodSupported(method: String) =
       Seq("at", "each", "eachWhere", "eachRight", "eachLeft", "atOrElse", "index", "when").contains(method)
 
@@ -84,10 +87,10 @@ object QuicklensMacros {
             else
               children.map {
                 case (sym, trees) if sym equiv symbol =>
-                  sym -> { trees.init ++ { trees.last match
+                  sym -> (trees.init ++ { trees.last match
                     case PathTree.Empty => Seq(PathTree.Empty, tail.toPathTree)
                     case node => Seq(node <> tail)
-                  }}
+                  })
                 case c => c
               }
           }
@@ -100,7 +103,6 @@ object QuicklensMacros {
       def toPathTree: PathTree = symbols match
         case Nil => PathTree.Empty
         case (symbol :: tail) => PathTree.Node(Seq(symbol -> Seq(tail.toPathTree)))
-
 
     enum PathSymbol:
       case Field(name: String)
@@ -139,13 +141,17 @@ object QuicklensMacros {
     }
 
     def termMethodByNameUnsafe(term: Term, name: String): Symbol = {
-      term.tpe.typeSymbol.memberMethod(name).head
+      term.tpe.typeSymbol
+        .memberMethod(name)
+        .headOption
+        .getOrElse(report.errorAndAbort(noSuchMember(term, name)))
     }
 
     def termAccessorMethodByNameUnsafe(term: Term, name: String): (Symbol, Int) = {
-      val caseFields = term.tpe.typeSymbol.caseFields
-      val idx = caseFields.map(_.name).indexOf(name)
-      (caseFields.find(_.name == name).get, idx + 1)
+      val caseParamNames = term.tpe.typeSymbol.primaryConstructor.paramSymss.flatten.filter(_.isTerm).map(_.name)
+      val idx = caseParamNames.indexOf(name)
+      term.tpe.typeSymbol.caseFields.find(_.name == name).getOrElse(report.errorAndAbort(noSuchMember(term, name)))
+        -> (idx + 1)
     }
 
     def caseClassCopy(
@@ -166,7 +172,7 @@ object QuicklensMacros {
           idx -> namedArg
         }.toMap
 
-        val fieldsIdxs = 1.to(obj.tpe.typeSymbol.caseFields.length)
+        val fieldsIdxs = 1.to(obj.tpe.typeSymbol.primaryConstructor.paramSymss.flatten.filter(_.isTerm).length)
         val args = fieldsIdxs.map { i =>
           argsMap.getOrElse(
             i,

diff --git a/quicklens/src/test/scala/com/softwaremill/quicklens/TupleModifyTest.scala b/quicklens/src/test/scala/com/softwaremill/quicklens/TupleModifyTest.scala
@@ -0,0 +1,29 @@
+package com.softwaremill.quicklens
+
+import org.scalatest.flatspec.AnyFlatSpec
+import org.scalatest.matchers.should.Matchers
+
+class TupleModifyTest extends AnyFlatSpec with Matchers {
+  it should "modify case classes using setTo" in {
+    case class Pair(a: Int, b: Int)
+    val p = Pair(0, 1)
+    val modified = p.modify(_.b).setTo(2)
+    modified shouldBe Pair(0, 2)
+  }
+  it should "modify tuples using setTo" in {
+    val tuple = (0, 1)
+    val modified = tuple.modify(_._2).setTo(2)
+    modified shouldBe ((0, 2))
+  }
+  it should "modify tuples using using" in {
+    val tuple4 = (0, 1, 2, 3)
+    val modified = tuple4.modify(_._3).using(_ + 1)
+    modified shouldBe ((0, 1, 3, 3))
+  }
+
+  it should "modify tuples using multiple modify" in {
+    val tuple4 = (0, 1, 2, 3)
+    val modified = tuple4.modify(_._3).using(_ + 1).modify(_._4).using(_ + 1)
+    modified shouldBe ((0, 1, 3, 4))
+  }
+}