Polish whenPushSatisfies

src/blueprint/dsl/pushTestPredicate.ts

@@ -14,18 +14,22 @@
  * limitations under the License.
  */
 
-import { isBoolean } from "util";
+import { PushToValue } from "../../common/listener/PushMapping";
 import { PushTest } from "../../common/listener/PushTest";
 import { isPushMapping, pushTest } from "../../index";
 
 /**
- * Predicate that can be used in our PushTest DSL
+ * Predicate that can be used in our PushTest DSL.
+ * Can be a PushTest, a function or computed boolean
  */
-export type PushTestPredicate = PushTest | boolean | (() => (boolean | Promise<boolean>));
+export type PushTestPredicate = PushTest | PushToValue<boolean> | boolean | (() => (boolean | Promise<boolean>));
 
 export function toPushTest(p: PushTestPredicate): PushTest {
-    return isPushMapping(p) ? p :
-        isBoolean(p) ?
-            pushTest(p + "", async () => p) :
-            pushTest(p + "", async () => p()) ;
+    if (isPushMapping(p)) {
+        return p;
+    }
+    if (typeof p === "boolean") {
+        return pushTest(p + "", async () => p);
+    }
+    return pushTest(p + "", p as any);
 }

src/common/listener/PushMapping.ts

@@ -24,6 +24,29 @@ export type NeverMatch = null;
  */
 export const DoNotSetAnyGoals: NeverMatch = null;
 
+/**
+ * Result of a PushMapping. A result of the desired type if
+ * we match. undefined if we don't match.
+ * Return DoNotSetAnyGoals (null) to shortcut evaluation of the present set of rules,
+ * terminating evaluation and guarantee the return of undefined if we've reached this point.
+ * Only do so if you are sure
+ */
+export type PushMappingResult<V> = Promise<V | undefined | NeverMatch>;
+
+/**
+ * Compute a value for the given push. Return undefined
+ * if we don't find a mapped value.
+ * Return DoNotSetAnyGoals (null) to shortcut evaluation of the present set of rules,
+ * terminating evaluation and guarantee the return of undefined if we've reached this point.
+ * Only do so if you are sure
+ * that this evaluation must be short circuited if it has reached this point.
+ * If a previous rule has matched, it will still be used.
+ * The value may be static
+ * or computed on demand, depending on the implementation.
+ * @param {PushListenerInvocation} p
+ */
+export type PushToValue<V> = (p: PushListenerInvocation) => PushMappingResult<V>;
+
 /**
  * Mapping from push to value, id it can be resolved.
  * This is a central interface used throughout the SDM.
@@ -46,9 +69,8 @@ export interface PushMapping<V> {
      * The value may be static
      * or computed on demand, depending on the implementation.
      * @param {PushListenerInvocation} p
-     * @return {Promise<V | undefined | NeverMatch>}
      */
-    valueForPush(p: PushListenerInvocation): Promise<V | undefined | NeverMatch>;
+    valueForPush: PushToValue<V>;
 }
 
 export function isPushMapping(a: any): a is PushMapping<any> {

test/blueprint/dsl/whenPushSatisfiesTest.ts

@@ -15,7 +15,8 @@
  */
 
 import * as assert from "power-assert";
-import { HttpServiceGoals, whenPushSatisfies } from "../../../src";
+import { whenPushSatisfies } from "../../../src/blueprint/dsl/goalDsl";
+import { HttpServiceGoals } from "../../../src/common/delivery/goals/common/httpServiceGoals";
 import { FalsePushTest, TruePushTest } from "../../common/listener/support/pushTestUtilsTest";
 import { fakePush } from "./decisionTreeTest";
 
@@ -65,4 +66,14 @@ describe("whenPushSatisfies", () => {
         const test = whenPushSatisfies(TruePushTest, FalsePushTest).setGoals(HttpServiceGoals);
         assert.equal(test.name, TruePushTest.name + " && " + FalsePushTest.name);
     });
+
+    it("should allow simple function", async () => {
+        const test = whenPushSatisfies(async p => true).setGoals(HttpServiceGoals);
+        assert.equal(await test.valueForPush(fakePush()), HttpServiceGoals);
+    });
+
+    it("should allow simple function returning false", async () => {
+        const test = whenPushSatisfies(async p => p.push.id === "notThis").setGoals(HttpServiceGoals);
+        assert.equal(await test.valueForPush(fakePush()), undefined);
+    });
 });