feat: Add descriptive cataloging form getter

Author: danmichaelo

src/Marc21.php

@@ -8,4 +8,12 @@ class Marc21
     const AUTHORITY = 'Authority';
     const BIBLIOGRAPHIC = 'Bibliographic';
     const HOLDINGS = 'Holdings';
+
+    // Descriptive cataloging forms
+    const NON_ISBD = ' ';
+    const AACR2 = 'a';
+    const ISBD_PUNCTUATION_OMITTED = 'c';
+    const ISBD_PUNCTUATION_INCLUDED = 'i';
+    const NON_ISBD_PUNCTUATION_OMITTED = 'n';
+    const UNKNOWN_CATALOGING_FORM = 'u';
 }

src/Record.php

@@ -106,6 +106,21 @@ public function getType()
         }
     }
 
+    /**
+     * Get the descriptive cataloging form value from LDR/18. Returns any of
+     * the constants Marc21::NON_ISBD, Marc21::AACR2, Marc21::ISBD_PUNCTUATION_OMITTED,
+     * Marc21::ISBD_PUNCTUATION_INCLUDED, Marc21::NON_ISBD_PUNCTUATION_OMITTED
+     * or Marc21::UNKNOWN_CATALOGING_FORM.
+     *
+     * @return string
+     * @throws UnknownRecordType
+     */
+    public function getCatalogingForm()
+    {
+        $leader = $this->record->getLeader();
+        return substr($leader, 18, 1);
+    }
+
     /*************************************************************************
      * Helper methods for specific fields. Each of these are supported by
      * a class in src/Fields/

tests/RecordTest.php

@@ -83,4 +83,15 @@ public function testRecordTypeAuthority()
         $record = Record::fromString($source);
         $this->assertEquals(Marc21::AUTHORITY, $record->type);
     }
+
+    public function testRecordTypeDescriptiveCatalogingForm()
+    {
+        $source = '<?xml version="1.0" encoding="UTF-8" ?>
+          <record>
+            <leader>99999cam a2299999 c 4500</leader>
+          </record>';
+
+        $record = Record::fromString($source);
+        $this->assertEquals(Marc21::ISBD_PUNCTUATION_OMITTED, $record->catalogingForm);
+    }
 }