feat(fio): new operator runtime

src/internals/Evaluate.ts

@@ -22,7 +22,7 @@ export const Evaluate = <E, A>(
   rej: CB<E>,
   res: CB<A>
 ): void => {
-  const {stackA, stackE, stackEnv, cancellationList, sh} = context
+  const {stackA, stackE, stackEnv, cancellationList, sh, runtime} = context
   let data: unknown
 
   while (true) {
@@ -97,6 +97,10 @@ export const Evaluate = <E, A>(
           data = j.i0(env)
           break
 
+        case Tag.Runtime:
+          data = runtime
+          break
+
         case Tag.Async:
           const id = cancellationList.push(
             j.i0(

src/internals/FiberContext.ts

@@ -8,6 +8,7 @@ import {Exit} from '../main/Exit'
 import {Fiber} from '../main/Fiber'
 import {FIO, UIO} from '../main/FIO'
 import {Instruction} from '../main/Instructions'
+import {IRuntime} from '../runtimes/IRuntime'
 
 import {CancellationList} from './CancellationList'
 import {CB} from './CB'
@@ -36,6 +37,7 @@ export class FiberContext<E = never, A = never> extends Fiber<E, A>
   public readonly stackEnv: unknown[] = []
 
   public constructor(
+    public readonly runtime: IRuntime,
     public readonly sh: IScheduler,
     io: Instruction,
     public readonly cancellationList: CancellationList = new CancellationList()
@@ -56,7 +58,7 @@ export class FiberContext<E = never, A = never> extends Fiber<E, A>
    *  Creates a new FiberContext with the provided instruction
    */
   public $fork<E2, A2>(ins: Instruction): FiberContext<E2, A2> {
-    return new FiberContext<E2, A2>(this.sh, ins)
+    return new FiberContext<E2, A2>(this.runtime, this.sh, ins)
   }
 
   /**

src/main/FIO.ts

@@ -8,6 +8,7 @@ import {ICancellable, IScheduler} from 'ts-scheduler'
 
 import {CB} from '../internals/CB'
 import {coordinate} from '../internals/Coordinate'
+import {IRuntime} from '../runtimes/IRuntime'
 
 import {Await} from './Await'
 import {Exit} from './Exit'
@@ -317,6 +318,13 @@ export class FIO<E1 = unknown, A1 = unknown, R1 = NoEnv> {
     return new FIO(Tag.TryM, cb)
   }
 
+  /**
+   * Returns the current runtime in a pure way.
+   */
+  public static runtime(): UIO<IRuntime> {
+    return new FIO(Tag.Runtime)
+  }
+
   /**
    * Executes the provided IOs in sequences and returns their intermediatory results as an Array.
    * Checkout [[FIO.par]] to run multiple IOs in parallel.

src/main/Instructions.ts

@@ -16,6 +16,7 @@ export enum Tag {
   Never,
   Provide,
   Reject,
+  Runtime,
   Try,
   TryM
 }
@@ -71,6 +72,9 @@ export interface IProvide<R = unknown> {
   i1: R
   tag: Tag.Provide
 }
+export interface IRuntime {
+  tag: Tag.Runtime
+}
 
 /**
  * @ignore
@@ -86,5 +90,6 @@ export type Instruction =
   | INever
   | IProvide
   | IReject
+  | IRuntime
   | ITry
   | ITryM

src/runtimes/BaseRuntime.ts

@@ -17,9 +17,10 @@ export abstract class BaseRuntime implements IRuntime {
     res: (e: A) => void = noop,
     rej: (e: E) => void = noop
   ): ICancellable {
-    return new FiberContext<E, A>(this.scheduler, io.asInstruction).$resume(
-      rej,
-      res
-    )
+    return new FiberContext<E, A>(
+      this,
+      this.scheduler,
+      io.asInstruction
+    ).$resume(rej, res)
   }
 }

test/FIO.test.ts

@@ -10,6 +10,7 @@ import {Exit} from '../src/main/Exit'
 import {Fiber} from '../src/main/Fiber'
 import {FIO, UIO} from '../src/main/FIO'
 import {defaultRuntime} from '../src/runtimes/DefaultRuntime'
+import {IRuntime} from '../src/runtimes/IRuntime'
 import {testRuntime} from '../src/runtimes/TestRuntime'
 
 import {Counter} from './internals/Counter'
@@ -591,4 +592,14 @@ describe('FIO', () => {
       assert.strictEqual(actual, expected)
     })
   })
+
+  describe('runtime', () => {
+    it('should give access to current runtime', () => {
+      const runtime = testRuntime()
+
+      const actual = runtime.executeSync(FIO.runtime())
+
+      assert.strictEqual(actual, runtime as IRuntime)
+    })
+  })
 })