Marc alternative titles

pipeline/transformer/transformer_marc_common/src/main/scala/weco/pipeline/transformer/marc_common/transformers/MarcAlternativeTitles.scala

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+package weco.pipeline.transformer.marc_common.transformers
+
+import weco.pipeline.transformer.marc_common.models.{
+  MarcField,
+  MarcRecord,
+  MarcSubfield
+}
+
+// Populate work:alternativeTitles
+//
+// The following fields are used as possible alternative titles:
+// * 240 $a https://www.loc.gov/marc/bibliographic/bd240.html
+// * 130 $a http://www.loc.gov/marc/bibliographic/bd130.html
+// * 246 $a https://www.loc.gov/marc/bibliographic/bd246.html
+
+object MarcAlternativeTitles extends MarcDataTransformer {
+
+  override type Output = Seq[String]
+
+  override def apply(record: MarcRecord): Seq[String] = {
+    record
+      .fieldsWithTags("240", "130", "246")
+      .withoutCaptionTitles
+      .map(field => alternativeTitle(field))
+      .filterNot(_.isEmpty)
+      .distinct
+  }
+
+  private def alternativeTitle(field: MarcField): String =
+    field.subfields.withoutUKLW.map(_.content).mkString(" ")
+
+  implicit private class FieldsOps(fields: Seq[MarcField]) {
+
+    // 246 with ind2 = 6 indicates a Caption Title
+    // "printed at the head of the first page of text. Caption title: may be generated with the note for display."
+    // This is not an alternative title that we want to capture here.
+    def withoutCaptionTitles: Seq[MarcField] =
+      fields filterNot {
+        field =>
+          field.marcTag == "246" && field.indicator2 == "6"
+      }
+  }
+  implicit private class SubfieldsOps(subfields: Seq[MarcSubfield]) {
+    // Any $5 subfield with contents `UkLW` is Wellcome Library-specific and
+    // should be omitted.
+    def withoutUKLW: Seq[MarcSubfield] =
+      subfields.filterNot(_ == MarcSubfield("5", "UkLW"))
+
+  }
+}

pipeline/transformer/transformer_marc_common/src/test/scala/weco/pipeline/transformer/marc_common/transformers/MarcAlternativeTitlesTest.scala

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+package weco.pipeline.transformer.marc_common.transformers
+
+import org.scalatest.LoneElement
+import org.scalatest.funspec.AnyFunSpec
+import org.scalatest.matchers.should.Matchers
+import org.scalatest.prop.TableDrivenPropertyChecks._
+import weco.pipeline.transformer.marc_common.generators.MarcTestRecord
+import weco.pipeline.transformer.marc_common.models.{MarcField, MarcSubfield}
+import scala.util.Random
+class MarcAlternativeTitlesTest
+    extends AnyFunSpec
+    with Matchers
+    with LoneElement {
+
+  describe("extracting alternative titles from 130, 240, and 246 fields") {
+    info("https://www.loc.gov/marc/bibliographic/bd130.html")
+    info("https://www.loc.gov/marc/bibliographic/bd240.html")
+    info("https://www.loc.gov/marc/bibliographic/bd246.html")
+    describe("returning nothing") {
+      it(
+        "does not extract alternative titles if 130, 240, and 246 are absent"
+      ) {
+        MarcAlternativeTitles(
+          MarcTestRecord(
+            fields = Seq(
+              MarcField(
+                marcTag = "999",
+                subfields = Seq(MarcSubfield(tag = "a", content = "mafeesh"))
+              )
+            )
+          )
+        ) shouldBe Nil
+      }
+
+      it("does not return an empty alternative title given an empty field") {
+        MarcAlternativeTitles(
+          MarcTestRecord(
+            fields = Seq(
+              MarcField(
+                marcTag = "130",
+                subfields = Seq(MarcSubfield(tag = "a", content = ""))
+              )
+            )
+          )
+        ) shouldBe Nil
+      }
+
+      it(
+        "does not return an empty alternative title given a field whose content is entirely filtered out"
+      ) {
+        MarcAlternativeTitles(
+          MarcTestRecord(
+            fields = Seq(
+              MarcField(
+                marcTag = "246",
+                subfields = Seq(MarcSubfield(tag = "5", content = "UkLW"))
+              )
+            )
+          )
+        ) shouldBe Nil
+      }
+
+      it("ignores 'caption title' fields, i.e. 246 fields with ind2=6") {
+        MarcAlternativeTitles(
+          MarcTestRecord(
+            fields = Seq(
+              MarcField(
+                marcTag = "246",
+                subfields =
+                  Seq(MarcSubfield(tag = "a", content = "I am a caption")),
+                indicator2 = "6"
+              )
+            )
+          )
+        ) shouldBe Nil
+      }
+
+    }
+  }
+  describe("extracting a single alternative title") {
+    forAll(
+      Table(
+        "tag",
+        "130",
+        "240",
+        "246"
+      )
+    ) {
+      tag =>
+        describe(s"extracting an alternative title from $tag") {
+          it(s"extracts an alternative tile from field $tag") {
+            MarcAlternativeTitles(
+              MarcTestRecord(
+                fields = Seq(
+                  MarcField(
+                    marcTag = tag,
+                    subfields =
+                      Seq(MarcSubfield(tag = "a", content = "mafeesh"))
+                  )
+                )
+              )
+            ).loneElement shouldBe "mafeesh"
+          }
+
+          it(
+            s"concatenates all subfields of $tag in document order to make the alternative title"
+          ) {
+            val shuffled = Random.shuffle(subfieldLists(tag))
+            val subfields = shuffled.map(
+              subtag => MarcSubfield(tag = subtag, content = subtag.toUpperCase)
+            )
+            val expectedTitle =
+              shuffled.map(_.toUpperCase).mkString(" ")
+
+            MarcAlternativeTitles(
+              MarcTestRecord(
+                fields = Seq(
+                  MarcField(
+                    marcTag = tag,
+                    subfields = subfields
+                  )
+                )
+              )
+            ).loneElement shouldBe expectedTitle
+          }
+          if (tag == "246") {
+            it("ignores subfield 246$5 if its value is UkLW") {
+              info("$5UkLW is Wellcome Library-specific and should be omitted")
+              info(
+                "$5 is non-repeating, so this example should not exist in Real Life"
+              )
+              info(" but this test demonstrates that the existence oof $5UkLW")
+              info(
+                " does not impact the transformer's ability to extract anything else"
+              )
+              MarcAlternativeTitles(
+                MarcTestRecord(
+                  fields = Seq(
+                    MarcField(
+                      marcTag = tag,
+                      subfields = Seq(
+                        MarcSubfield(tag = "a", content = "Pinakes"),
+                        MarcSubfield(tag = "5", content = "UkLW"),
+                        MarcSubfield(tag = "5", content = "Mouseion")
+                      )
+                    )
+                  )
+                )
+              ).loneElement shouldBe "Pinakes Mouseion"
+            }
+          }
+        }
+    }
+  }
+  describe("extracting multiple alternative titles") {
+    it("extracts alternative titles from all relevant fields") {
+      MarcAlternativeTitles(
+        MarcTestRecord(
+          fields = Seq(
+            MarcField(
+              marcTag = "130",
+              subfields = Seq(
+                MarcSubfield(
+                  tag = "a",
+                  content = "I'm very well acquainted too"
+                )
+              )
+            ),
+            MarcField(
+              marcTag = "240",
+              subfields = Seq(
+                MarcSubfield(tag = "a", content = "with matters mathematical")
+              )
+            ),
+            MarcField(
+              marcTag = "246",
+              subfields =
+                Seq(MarcSubfield(tag = "a", content = "I understand equations"))
+            ),
+            MarcField(
+              marcTag = "246",
+              subfields = Seq(MarcSubfield(tag = "a", content = "both simple"))
+            ),
+            MarcField(
+              marcTag = "240",
+              subfields =
+                Seq(MarcSubfield(tag = "a", content = "and quadratical"))
+            ),
+            MarcField(
+              marcTag = "130",
+              subfields = Seq(
+                MarcSubfield(
+                  tag = "a",
+                  content =
+                    "About binomial theorem I am teeming with a lot o' news"
+                )
+              )
+            )
+          )
+        )
+      ) should contain theSameElementsAs Seq(
+        "I'm very well acquainted too",
+        "with matters mathematical",
+        "I understand equations",
+        "both simple",
+        "and quadratical",
+        "About binomial theorem I am teeming with a lot o' news"
+      )
+    }
+    it("does not return duplicate alternative titles") {
+      MarcAlternativeTitles(
+        MarcTestRecord(
+          fields = Seq(
+            MarcField(
+              marcTag = "130",
+              subfields = Seq(
+                MarcSubfield(
+                  tag = "a",
+                  content =
+                    "With many cheerful facts about the square of the hypotenuse"
+                )
+              )
+            ),
+            MarcField(
+              marcTag = "240",
+              subfields = Seq(
+                MarcSubfield(
+                  tag = "a",
+                  content =
+                    "With many cheerful facts about the square of the hypotenuse"
+                )
+              )
+            ),
+            MarcField(
+              marcTag = "246",
+              subfields = Seq(
+                MarcSubfield(
+                  tag = "a",
+                  content =
+                    "With many cheerful facts about the square of the hypotenuse"
+                )
+              )
+            ),
+            MarcField(
+              marcTag = "246",
+              subfields = Seq(
+                MarcSubfield(
+                  tag = "a",
+                  content =
+                    "With many cheerful facts about the square of the hypoten-potenuse"
+                )
+              )
+            )
+          )
+        )
+      ) should contain theSameElementsAs Seq(
+        "With many cheerful facts about the square of the hypotenuse",
+        "With many cheerful facts about the square of the hypoten-potenuse"
+      )
+    }
+    it("only filters on ind2=6 for 246 fields") {
+      info("246 with indicator2 is a caption title")
+      info("this is not true of 130 and 240")
+      val fields = Seq(
+        "130" -> "I am not a caption",
+        "246" -> "I am a caption",
+        "240" -> "Nor am I"
+      ) map {
+        case (tag, content) =>
+          MarcField(
+            indicator2 = "6",
+            marcTag = tag,
+            subfields = Seq(
+              MarcSubfield(
+                tag = "a",
+                content = content
+              )
+            )
+          )
+      }
+
+      MarcAlternativeTitles(
+        MarcTestRecord(fields = fields)
+      ) should contain theSameElementsAs Seq(
+        "I am not a caption",
+        "Nor am I"
+      )
+    }
+  }
+
+  private val subfieldLists = Map(
+    "130" -> Seq(
+      "a",
+      "d",
+      "f",
+      "g",
+      "h",
+      "k",
+      "l",
+      "m",
+      "n",
+      "o",
+      "p",
+      "r",
+      "s",
+      "t",
+      "0",
+      "1",
+      "2",
+      "6",
+      "7",
+      "8"
+    ),
+    "240" -> Seq(
+      "a",
+      "d",
+      "f",
+      "g",
+      "h",
+      "k",
+      "l",
+      "m",
+      "n",
+      "o",
+      "p",
+      "r",
+      "s",
+      "0",
+      "1",
+      "2",
+      "6",
+      "7",
+      "8"
+    ),
+    "246" -> Seq("a", "b", "f", "g", "h", "i", "n", "p", "5", "6", "7", "8")
+  )
+}