Merge 0612cb1 into c74c9f8

package.json

@@ -77,6 +77,7 @@
     "tape": "^4.2.2",
     "ts-jest": "^22.0.0",
     "tslib": "^1.7.1",
+    "tslint-config-prettier": "^1.17.0",
     "typescript": "^3.2.1",
     "uglify-es": "^3.3.9"
   },

src/api/flow.ts

@@ -4,16 +4,31 @@ let generatorId = 0
 
 export type CancellablePromise<T> = Promise<T> & { cancel(): void }
 
-export interface FlowIterator<T> {
-    next(value?: any): IteratorResult<T> | Promise<IteratorResult<T>>
-    return?(value?: any): IteratorResult<T> | Promise<IteratorResult<T>>
-    throw?(e?: any): IteratorResult<T> | Promise<IteratorResult<T>>
+export interface FlowYield {
+    // fake, only for typing
+    "!!flowYield": undefined
 }
 
-export function flow<T, U extends any[]>(
-    generator: (...args: U) => FlowIterator<any>
-): (...args: U) => CancellablePromise<T>
-export function flow(generator: Function): Function {
+export interface FlowReturn<T> {
+    // fake, only for typing
+    "!!flowReturn": T
+}
+
+// we skip promises that are the result of yielding promises (except if they use flowReturn)
+export type FlowReturnType<R> = IfAllAreFlowYieldThenVoid<
+    R extends FlowReturn<infer FR>
+        ? FR extends Promise<infer FRP> ? FRP : FR
+        : R extends Promise<any> ? FlowYield : R
+>
+
+// we extract yielded promises from the return type
+export type IfAllAreFlowYieldThenVoid<R> = Exclude<R, FlowYield> extends never
+    ? void
+    : Exclude<R, FlowYield>
+
+export function flow<R, Args extends any[]>(
+    generator: (...args: Args) => IterableIterator<R>
+): (...args: Args) => CancellablePromise<FlowReturnType<R>> {
     if (arguments.length !== 1)
         fail(process.env.NODE_ENV && `Flow expects one 1 argument and cannot be used as decorator`)
     const name = generator.name || "<unnamed flow>"
@@ -27,7 +42,7 @@ export function flow(generator: Function): Function {
         let rejector: (error: any) => void
         let pendingPromise: CancellablePromise<any> | undefined = undefined
 
-        const res = new Promise(function(resolve, reject) {
+        const promise = new Promise<R>(function(resolve, reject) {
             let stepId = 0
             rejector = reject
 
@@ -74,7 +89,7 @@ export function flow(generator: Function): Function {
             onFulfilled(undefined) // kick off the process
         }) as any
 
-        res.cancel = action(`${name} - runid: ${runId} - cancel`, function() {
+        promise.cancel = action(`${name} - runid: ${runId} - cancel`, function() {
             try {
                 if (pendingPromise) cancelPromise(pendingPromise)
                 // Finally block can return (or yield) stuff..
@@ -89,10 +104,22 @@ export function flow(generator: Function): Function {
                 rejector(e) // there could be a throwing finally block
             }
         })
-        return res
+        return promise as CancellablePromise<FlowReturnType<R>>
     }
 }
 
 function cancelPromise(promise) {
     if (typeof promise.cancel === "function") promise.cancel()
 }
+
+/**
+ * Used for TypeScript to make flows that return a promise return the actual promise result.
+ *
+ * @export
+ * @template T
+ * @param {T} val
+ * @returns {FlowReturn<T>}
+ */
+export function castFlowReturn<T>(val: T): FlowReturn<T> {
+    return val as any
+}

src/mobx.ts

@@ -29,7 +29,7 @@ try {
     // (in which case the expression below would be substituted with 'production')
     process.env.NODE_ENV
 } catch (e) {
-    var g = typeof window !== "undefined" ? window : global
+    const g = typeof window !== "undefined" ? window : global
     if (typeof process === "undefined") g.process = {}
     g.process.env = {}
 }
@@ -125,6 +125,7 @@ export {
     onBecomeObserved,
     onBecomeUnobserved,
     flow,
+    castFlowReturn,
     toJS,
     trace,
     IObserverTree,

test/base/api.js

@@ -20,6 +20,7 @@ test("correct api should be exposed", function() {
             "decorate",
             "extendObservable",
             "flow",
+            "castFlowReturn",
             "get",
             "_getAdministration",
             "getAtom",

test/base/flow.js

@@ -1,5 +1,5 @@
 import * as mobx from "../../src/mobx.ts"
-const { flow } = mobx
+import { castFlowReturn, flow } from "../../src/mobx"
 
 function delay(time, value, shouldThrow = false) {
     return new Promise((resolve, reject) => {
@@ -349,3 +349,7 @@ test("cancelled flow should not result in runaway reject", async () => {
         expect("" + e).toBe("Error: FLOW_CANCELLED")
     }
 })
+
+test("castFlowReturn should return the passed argument", () => {
+    expect(castFlowReturn(5)).toBe(5)
+})

tslint.json

@@ -1,55 +1,26 @@
 {
+    "extends": ["tslint-config-prettier"],
     "rules": {
         "class-name": true,
-        "comment-format": [
-            true,
-            "check-space"
-        ],
+        "comment-format": [true, "check-space"],
         "curly": false,
-        "indent": [
-            true,
-            "tabs"
-        ],
-        "interface-name": true,
+        "interface-name": false,
         "jsdoc-format": true,
-        "no-consecutive-blank-lines" : true,
+        "no-consecutive-blank-lines": true,
         "no-debugger": true,
         "no-duplicate-key": true,
         "no-duplicate-variable": true,
         "no-eval": true,
         "no-internal-module": true,
-        "no-trailing-whitespace": true,
         "no-shadowed-variable": true,
         "no-switch-case-fall-through": true,
         "no-unreachable": true,
         "no-unused-expression": true,
-        "no_unused-variable": [
-            true
-        ],
+        "no_unused-variable": [true],
         "no-use-before-declare": false,
         "no-var-keyword": true,
-        "one-line": [
-            true,
-            "check-open-brace",
-            "check-whitespace",
-            "check-catch"
-        ],
-        "quotemark": [
-            true,
-            "double"
-        ],
-        "semicolon": true,
-        "trailing-comma": [
-            true,
-            {
-                "multiline": "never",
-                "singleline": "never"
-            }
-        ],
-        "triple-equals": [
-            true,
-            "allow-null-check"
-        ],
+        "one-line": [true, "check-open-brace", "check-whitespace", "check-catch"],
+        "triple-equals": [true, "allow-null-check"],
         "typedef-whitespace": [
             true,
             {
@@ -60,17 +31,6 @@
                 "variable-declaration": "nospace"
             }
         ],
-        "variable-name": [
-            true,
-            "ban-keywords"
-        ],
-        "whitespace": [
-            true,
-            "check-branch",
-            "check-decl",
-            "check-operator",
-            "check-separator",
-            "check-type"
-        ]
+        "variable-name": [true, "ban-keywords"]
     }
 }

yarn.lock

@@ -6031,6 +6031,11 @@ tslib@^1.7.1:
   version "1.9.1"
   resolved "https://registry.yarnpkg.com/tslib/-/tslib-1.9.1.tgz#a5d1f0532a49221c87755cfcc89ca37197242ba7"
 
+tslint-config-prettier@^1.17.0:
+  version "1.17.0"
+  resolved "https://registry.yarnpkg.com/tslint-config-prettier/-/tslint-config-prettier-1.17.0.tgz#946ed6117f98f3659a65848279156d87628c33dc"
+  integrity sha512-NKWNkThwqE4Snn4Cm6SZB7lV5RMDDFsBwz6fWUkTxOKGjMx8ycOHnjIbhn7dZd5XmssW3CwqUjlANR6EhP9YQw==
+
 tty-browserify@0.0.0, tty-browserify@~0.0.0:
   version "0.0.0"
   resolved "https://registry.yarnpkg.com/tty-browserify/-/tty-browserify-0.0.0.tgz#a157ba402da24e9bf957f9aa69d524eed42901a6"