Merged in task/main-cris/DSC-2140 (pull request DSpace#2690)

Task/main cris/DSC-2140

Approved-by: Francesco Molinaro

src/app/core/shared/metadata.utils.spec.ts

@@ -7,7 +7,10 @@ import {
   MetadataValueFilter,
   MetadatumViewModel,
 } from './metadata.models';
-import { Metadata } from './metadata.utils';
+import {
+  Metadata,
+  PLACEHOLDER_VALUE,
+} from './metadata.utils';
 
 const mdValue = (value: string, language?: string, authority?: string): MetadataValue => {
   return Object.assign(new MetadataValue(), {
@@ -50,19 +53,20 @@ const multiViewModelList = [
   { key: 'foo', ...bar, order: 0 },
 ];
 
-const testMethod = (fn, resultKind, mapOrMaps, keyOrKeys, expected, filter?) => {
+const testMethod = (fn, resultKind, mapOrMaps, keyOrKeys, expected, filter?, limit?: number) => {
   const keys = keyOrKeys instanceof Array ? keyOrKeys : [keyOrKeys];
   describe('and key' + (keys.length === 1 ? (' ' + keys[0]) : ('s ' + JSON.stringify(keys)))
     + ' with ' + (isUndefined(filter) ? 'no filter' : 'filter ' + JSON.stringify(filter)), () => {
-    const result = fn(mapOrMaps, keys, filter);
+    const result = fn(mapOrMaps, keys, filter, limit);
     let shouldReturn;
     if (resultKind === 'boolean') {
       shouldReturn = expected;
     } else if (isUndefined(expected)) {
       shouldReturn = 'undefined';
     } else if (expected instanceof Array) {
       shouldReturn = 'an array with ' + expected.length + ' ' + (expected.length > 1 ? 'ordered ' : '')
-        + resultKind + (expected.length !== 1 ? 's' : '');
+        + resultKind + (expected.length !== 1 ? 's' : '')
+        + (isUndefined(limit) ? '' : ' (limited to ' + limit + ')');
     } else {
       shouldReturn = 'a ' + resultKind;
     }
@@ -303,4 +307,29 @@ describe('Metadata', () => {
 
   });
 
+  describe('all method with limit', () => {
+    const testAllWithLimit = (mapOrMaps, keyOrKeys, expected, limit) =>
+      testMethod(Metadata.all, 'value', mapOrMaps, keyOrKeys, expected, undefined, limit);
+
+    describe('with multiMap and limit', () => {
+      testAllWithLimit(multiMap, 'dc.title', [dcTitle1], 1);
+    });
+  });
+
+  describe('Placeholder values', () => {
+    it('should ignore placeholder values in get methods', () => {
+      const placeholderMd = mdValue(PLACEHOLDER_VALUE);
+      const key = 'dc.test.placeholder';
+      const map = { 'dc.test.placeholder': [placeholderMd] };
+
+      expect(Metadata.all(map, key).length).toEqual(0);
+      expect(Metadata.allValues(map, key).length).toEqual(0);
+      expect(Metadata.has(map, key)).toBeFalsy();
+      expect(Metadata.first(map, key)).toBeUndefined();
+      expect(Metadata.firstValue(map, key)).toBeUndefined();
+      expect(Metadata.hasValue(placeholderMd)).toBeFalsy();
+      expect(Metadata.valueMatches(placeholderMd, null)).toBeFalsy();
+    });
+  });
+
 });

src/app/core/shared/metadata.utils.ts

@@ -21,6 +21,8 @@ import {
 
 export const AUTHORITY_GENERATE = 'will be generated::';
 export const AUTHORITY_REFERENCE = 'will be referenced::';
+export const PLACEHOLDER_VALUE = '#PLACEHOLDER_PARENT_METADATA_VALUE#';
+
 
 /**
  * Utility class for working with DSpace object metadata.
@@ -36,18 +38,21 @@ export const AUTHORITY_REFERENCE = 'will be referenced::';
  * followed by any other (non-dc) metadata values.
  */
 export class Metadata {
-
   /**
    * Gets all matching metadata in the map(s).
    *
    * @param {MetadataMapInterface|MetadataMapInterface[]} mapOrMaps The source map(s). When multiple maps are given, they will be
    * checked in order, and only values from the first with at least one match will be returned.
    * @param {string|string[]} keyOrKeys The metadata key(s) in scope. Wildcards are supported; see above.
    * @param {MetadataValueFilter} filter The value filter to use. If unspecified, no filtering will be done.
+   * @param {number} limit The maximum number of values to return. If unspecified, all matching values will be returned.
    * @returns {MetadataValue[]} the matching values or an empty array.
    */
-  public static all(mapOrMaps: MetadataMapInterface | MetadataMapInterface[], keyOrKeys: string | string[],
-    filter?: MetadataValueFilter): MetadataValue[] {
+  public static all(
+    mapOrMaps: MetadataMapInterface | MetadataMapInterface[],
+    keyOrKeys: string | string[],
+    filter?: MetadataValueFilter,
+    limit?: number): MetadataValue[] {
     const mdMaps: MetadataMapInterface[] = mapOrMaps instanceof Array ? mapOrMaps : [mapOrMaps];
     const matches: MetadataValue[] = [];
     for (const mdMap of mdMaps) {
@@ -57,6 +62,9 @@ export class Metadata {
           for (const candidate of candidates) {
             if (Metadata.valueMatches(candidate as MetadataValue, filter)) {
               matches.push(candidate as MetadataValue);
+              if (hasValue(limit) && matches.length >= limit) {
+                return  matches;
+              }
             }
           }
         }
@@ -155,11 +163,11 @@ export class Metadata {
    * Returns true if this Metadatum's value is defined
    */
   public static hasValue(value: MetadataValue|string): boolean {
-    if (isEmpty(value)) {
+    if (isEmpty(value) || value === PLACEHOLDER_VALUE) {
       return false;
     }
     if (isObject(value) && value.hasOwnProperty('value')) {
-      return isNotEmpty(value.value);
+      return isNotEmpty(value.value) && value.value !== PLACEHOLDER_VALUE;
     }
     return true;
   }
@@ -172,7 +180,9 @@ export class Metadata {
    * @returns {boolean} whether the filter matches, or true if no filter is given.
    */
   public static valueMatches(mdValue: MetadataValue, filter: MetadataValueFilter) {
-    if (!filter) {
+    if (mdValue.value === PLACEHOLDER_VALUE) {
+      return false;
+    } else if (!filter) {
       return true;
     } else if (filter.language && filter.language !== mdValue.language) {
       return false;