Add "Stop" button

src/components/IDE/Control.tsx

@@ -7,9 +7,11 @@ import { Button, IconName, Intent } from '@blueprintjs/core'
  *           of the editor's content, using `slang`
  */
 export interface IControlProps {
+  isRunning: boolean
   handleEvalEditor: () => void
   handleEvalRepl: () => void
   handleClearReplOutput: () => void
+  handleInterruptEval: () => void
 }
 
 class Control extends React.Component<IControlProps, {}> {
@@ -30,12 +32,20 @@ class Control extends React.Component<IControlProps, {}> {
         {label}
       </Button>
     )
-    const runButton = genericButton('Run', 'play', this.props.handleEvalEditor)
+    const runButton = this.props.isRunning
+      ? null
+      : genericButton('Run', 'play', this.props.handleEvalEditor)
+    const stopButton = this.props.isRunning
+      ? genericButton('Stop', 'stop', this.props.handleInterruptEval)
+      : null
     const evalButton = genericButton('Eval', 'play', this.props.handleEvalRepl)
     const clearButton = genericButton('Clear', 'remove', this.props.handleClearReplOutput)
     return (
       <div className="row between-xs">
-        <div className="col-xs-2">{runButton}</div>
+        <div className="col-xs-2">
+          {runButton}
+          {stopButton}
+        </div>
         <div className="col-xs-4">
           <div className="row">
             <div className="col-xs-6">{evalButton}</div>

src/components/IDE/__tests__/Control.tsx

@@ -6,9 +6,11 @@ import Control, { IControlProps } from '../Control'
 
 test('Control renders correctly', () => {
   const props: IControlProps = {
+    isRunning: false,
     handleEvalEditor: () => {},
     handleEvalRepl: () => {},
-    handleClearReplOutput: () => {}
+    handleClearReplOutput: () => {},
+    handleInterruptEval: () => {}
   }
   const app = <Control {...props} />
   const tree = shallow(app)

src/containers/IDE/ControlContainer.ts

@@ -1,16 +1,22 @@
 import { connect, MapDispatchToProps, MapStateToProps } from 'react-redux'
 import { bindActionCreators, Dispatch } from 'redux'
 
+import { handleInterruptExecution } from '../../actions/interpreter'
 import { clearReplOutput, evalEditor, evalRepl } from '../../actions/playground'
 import Control, { IControlProps } from '../../components/IDE/Control'
 import { IState } from '../../reducers/states'
 
+type StateProps = Pick<IControlProps, 'isRunning'>
+
 type DispatchProps = Pick<IControlProps, 'handleEvalEditor'> &
   Pick<IControlProps, 'handleEvalRepl'> &
-  Pick<IControlProps, 'handleClearReplOutput'>
+  Pick<IControlProps, 'handleClearReplOutput'> &
+  Pick<IControlProps, 'handleInterruptEval'>
 
 /** No-op mapStateToProps */
-const mapStateToProps: MapStateToProps<{}, {}, IState> = state => ({})
+const mapStateToProps: MapStateToProps<StateProps, {}, IState> = state => ({
+  isRunning: state.playground.isRunning
+})
 
 /** Provides a callback function `handleEvalEditor`
  *  to evaluate code in the Editor.
@@ -20,7 +26,8 @@ const mapDispatchToProps: MapDispatchToProps<DispatchProps, {}> = (dispatch: Dis
     {
       handleEvalEditor: evalEditor,
       handleEvalRepl: evalRepl,
-      handleClearReplOutput: clearReplOutput
+      handleClearReplOutput: clearReplOutput,
+      handleInterruptEval: handleInterruptExecution
     },
     dispatch
   )

src/reducers/playground.ts

@@ -3,10 +3,13 @@ import {
   CLEAR_CONTEXT,
   CLEAR_REPL_INPUT,
   CLEAR_REPL_OUTPUT,
+  EVAL_EDITOR,
+  EVAL_INTERPRETER,
   EVAL_INTERPRETER_ERROR,
   EVAL_INTERPRETER_SUCCESS,
   HANDLE_CONSOLE_LOG,
   IAction,
+  INTERRUPT_EXECUTION,
   SEND_REPL_INPUT_TO_OUTPUT,
   UPDATE_EDITOR_VALUE,
   UPDATE_REPL_VALUE
@@ -68,6 +71,16 @@ export const reducer: Reducer<IPlaygroundState> = (state = defaultPlayground, ac
         ...state,
         output: newOutput
       }
+    case EVAL_EDITOR:
+      return {
+        ...state,
+        isRunning: true
+      }
+    case EVAL_INTERPRETER:
+      return {
+        ...state,
+        isRunning: true
+      }
     case EVAL_INTERPRETER_SUCCESS:
       lastOutput = state.output.slice(-1)[0]
       if (lastOutput !== undefined && lastOutput.type === 'running') {
@@ -83,7 +96,8 @@ export const reducer: Reducer<IPlaygroundState> = (state = defaultPlayground, ac
       }
       return {
         ...state,
-        output: newOutput
+        output: newOutput,
+        isRunning: false
       }
     case EVAL_INTERPRETER_ERROR:
       lastOutput = state.output.slice(-1)[0]
@@ -100,7 +114,13 @@ export const reducer: Reducer<IPlaygroundState> = (state = defaultPlayground, ac
       }
       return {
         ...state,
-        output: newOutput
+        output: newOutput,
+        isRunning: false
+      }
+    case INTERRUPT_EXECUTION:
+      return {
+        ...state,
+        isRunning: false
       }
     default:
       return state

src/reducers/states.ts

@@ -16,6 +16,7 @@ export interface IPlaygroundState {
   readonly replValue: string
   readonly context: Context
   readonly output: InterpreterOutput[]
+  readonly isRunning: boolean
 }
 
 /**
@@ -90,5 +91,6 @@ export const defaultPlayground: IPlaygroundState = {
   editorValue: '',
   replValue: '',
   context: createContext(),
-  output: []
+  output: [],
+  isRunning: false
 }

src/sagas/index.ts

@@ -6,6 +6,7 @@ import { Context, interrupt, runInContext } from '../slang'
 
 import * as actions from '../actions'
 import * as actionTypes from '../actions/actionTypes'
+import { showWarningMessage } from '../notification'
 
 function* evalCode(code: string, context: Context) {
   const { result, interrupted } = yield race({
@@ -20,6 +21,7 @@ function* evalCode(code: string, context: Context) {
     }
   } else if (interrupted) {
     interrupt(context)
+    yield call(showWarningMessage, 'Execution aborted by user')
   }
 }
 
@@ -29,7 +31,6 @@ function* interpreterSaga(): SagaIterator {
 
   yield takeEvery(actionTypes.EVAL_EDITOR, function*() {
     const code: string = yield select((state: IState) => state.playground.editorValue)
-    yield put(actions.handleInterruptExecution())
     yield put(actions.clearContext())
     yield put(actions.clearReplOutput())
     context = yield select((state: IState) => state.playground.context)
@@ -39,7 +40,6 @@ function* interpreterSaga(): SagaIterator {
   yield takeEvery(actionTypes.EVAL_REPL, function*() {
     const code: string = yield select((state: IState) => state.playground.replValue)
     context = yield select((state: IState) => state.playground.context)
-    yield put(actions.handleInterruptExecution())
     yield put(actions.clearReplInput())
     yield put(actions.sendReplInputToOutput(code))
     yield* evalCode(code, context)