fix(search): allow NOT as a standalone modifier

AFFECTS PACKAGES:
@esri/arcgis-rest-portal

ISSUES CLOSED: #542

packages/arcgis-rest-portal/src/util/SearchQueryBuilder.ts

@@ -176,15 +176,19 @@ export class SearchQueryBuilder implements IParamBuilder {
   }
 
   /**
-   * Joins two sets of queries with a `NOT` clause.
+   * Joins two sets of queries with a `NOT` clause. Another option for filtering results is the [prohibit operator '-'](https://developers.arcgis.com/rest/users-groups-and-items/search-reference.htm#ESRI_SECTION1_5C6C35DB9E4A4F4492C5B937BDA2BF67).
    *
    * ```js
+   * // omit results with "Rivers" in their title
    * const query = new SearchQueryBuilder()
-   *   .match("Water")
-   *   .in("title")
    *   .not()
    *   .match("Rivers")
    *   .in("title")
+   *
+   * // equivalent
+   * const query = new SearchQueryBuilder()
+   *   .match("Rivers")
+   *   .in("-title")
    * ```
    */
   public not(this: SearchQueryBuilder) {
@@ -283,15 +287,16 @@ export class SearchQueryBuilder implements IParamBuilder {
 
     this.commit();
 
-    if (this.q === "") {
+    if (this.q === "" && modifier !== "not") {
       warn(
         `You have called \`${modifier}()\` without calling another method to modify your query first. Try calling \`match()\` first.`
       );
       return this;
     }
 
     this.currentModifer = modifier;
-    this.q += ` ${modifier.toUpperCase()} `;
+    this.q += this.q === "" ? "" : " ";
+    this.q += `${modifier.toUpperCase()} `;
     return this;
   }
 

packages/arcgis-rest-portal/test/util/SearchQueryBuilder.test.ts

@@ -152,6 +152,19 @@ describe("SearchQueryBuilder", () => {
     );
   });
 
+  it("should allow .not to be called without a preceding search value", () => {
+    const query = new SearchQueryBuilder()
+      .not()
+      .match("public")
+      .in("access")
+      .not()
+      .match("code attachment")
+      .in("type")
+      .toParam();
+
+    expect(query).toEqual(`NOT access:public NOT type:"code attachment"`);
+  });
+
   it("should clone searches for modification", () => {
     const myAppsQuery = new SearchQueryBuilder()
       .match("fred")
@@ -195,11 +208,8 @@ describe("SearchQueryBuilder", () => {
 
   it("should not allow chains of logic modifiers, and warn user", () => {
     const query = new SearchQueryBuilder()
-      .not()
       .and()
       .or()
-      .not()
-      .or()
       .or()
       .toParam();
 
@@ -323,7 +333,7 @@ describe("SearchQueryBuilder", () => {
     expect(query).toEqual("title:test");
   });
 
-  it("should", () => {
+  it("should produce an empty string when no methods are called", () => {
     const query = new SearchQueryBuilder().toParam();
     expect(query).toEqual("");
   });