Fix search saving, and add some unit tests

Also:

- Return an object from `Zotero.Search.prototype.getConditions()`
  instead of an array.
- Add support function `getPromiseError(promise)` to return the error
  thrown from a chain of promises, or false if none. (We could make an
  `assert.throwsAsync()`, but this allows testing of various properties
  such as `.name`, which even the built-in `assert.throws()` can't
  test.)
- Clarify some search save errors

test/content/support.js

@@ -114,6 +114,13 @@ function waitForCallback(cb, interval, timeout) {
 	return deferred.promise;
 }
 
+/**
+ * Return a promise for the error thrown by a promise, or false if none
+ */
+function getPromiseError(promise) {
+	return promise.thenReturn(false).catch(e => e);
+}
+
 /**
  * Ensures that the PDF tools are installed, or installs them if not.
  * Returns a promise.

test/tests/searchTests.js

@@ -0,0 +1,47 @@
+describe("Zotero.Search", function() {
+	describe("#save()", function () {
+		it("should fail without a libraryID", function* () {
+			var s = new Zotero.Search;
+			s.name = "Test";
+			s.addCondition('title', 'is', 'test');
+			var e = yield getPromiseError(s.save());
+			assert.ok(e);
+			assert.equal(e.constructor.name, Error.prototype.constructor.name); // TEMP: Error mismatch
+			assert.equal(e.message, "libraryID must be set before saving search");
+		});
+		
+		it("should fail without a name", function* () {
+			var s = new Zotero.Search;
+			s.libraryID = Zotero.Libraries.userLibraryID;
+			s.addCondition('title', 'is', 'test');
+			var e = yield getPromiseError(s.save());
+			assert.ok(e);
+			assert.equal(e.constructor.name, Error.prototype.constructor.name); // TEMP: Error mismatch
+			assert.equal(e.message, "Name not provided for saved search");
+		});
+		
+		it("should save a new search", function* () {
+			// Save search
+			var s = new Zotero.Search;
+			s.libraryID = Zotero.Libraries.userLibraryID;
+			s.name = "Test";
+			s.addCondition('title', 'is', 'test');
+			var id = yield s.save();
+			assert.typeOf(id, 'number');
+			
+			// Check saved search
+			s = yield Zotero.Searches.getAsync(id);
+			assert.ok(s);
+			assert.instanceOf(s, Zotero.Search);
+			assert.equal(s.name, "Test");
+			yield s.loadConditions();
+			var conditions = s.getConditions();
+			assert.lengthOf(Object.keys(conditions), 1);
+			assert.property(conditions, "1"); // searchConditionIDs start at 1
+			var condition = conditions[1];
+			assert.propertyVal(condition, 'condition', 'title')
+			assert.propertyVal(condition, 'operator', 'is')
+			assert.propertyVal(condition, 'value', 'test')
+		});
+	});
+});