made stdin discarder singleton

index.js

@@ -11,9 +11,88 @@ const TEXT = Symbol('text');
 const PREFIX_TEXT = Symbol('prefixText');
 
 const noop = () => {};
-
 const ASCII_ETX_CODE = 0x03; // Ctrl+C emits this code
 
+class StdinDiscarder {
+	constructor() {
+		this.requests = 0;
+
+		const self = this;
+		this.ourEmit = function (event, data, ...args) {
+			const {stdin} = process;
+			if (self.requests > 0 || stdin.emit === self.ourEmit) {
+				if (event === 'keypress') { // Fixes readline behavior
+					return;
+				}
+
+				if (event === 'data' && data.includes(ASCII_ETX_CODE)) {
+					process.emit('SIGINT');
+				}
+
+				self.oldEmit.apply(this, [event, data, ...args]);
+			} else {
+				process.stdin.emit.apply(this, [event, data, ...args]);
+			}
+		};
+	}
+
+	start() {
+		this.requests++;
+
+		if (this.requests === 1) {
+			this.realStart();
+		}
+	}
+
+	stop() {
+		if (this.requests <= 0) {
+			throw new Error('`stop` called more times than `start`');
+		}
+
+		this.requests--;
+
+		if (this.requests === 0) {
+			this.realStop();
+		}
+	}
+
+	realStart() {
+		const {stdin} = process;
+
+		this.oldRawMode = stdin.isRaw;
+		this.oldEmit = stdin.emit;
+		this.oldEmitOwnProperty = Object.prototype.hasOwnProperty.call(stdin, 'emit');
+
+		stdin.setRawMode(true);
+		stdin.on('data', noop);
+		stdin.resume();
+
+		stdin.emit = this.ourEmit;
+	}
+
+	realStop() {
+		const {stdin} = process;
+
+		if (this.oldEmitOwnProperty) {
+			stdin.emit = this.oldEmit;
+		} else {
+			delete stdin.emit;
+		}
+
+		this.oldRawMode = undefined;
+		this.oldEmit = undefined;
+		this.oldEmitOwnProperty = undefined;
+
+		stdin.setRawMode(this.oldRawMode);
+		stdin.removeListener('data', noop);
+		if (stdin.listenerCount('data') === 0) {
+			stdin.pause();
+		}
+	}
+}
+
+const stdinDiscarder = new StdinDiscarder();
+
 class Ora {
 	constructor(options) {
 		if (typeof options === 'string') {
@@ -45,6 +124,7 @@ class Ora {
 		this.linesToClear = 0;
 		this.indent = this.options.indent;
 		this.discardStdin = this.options.discardStdin;
+		this.isDiscardingStdin = false;
 	}
 
 	get indent() {
@@ -183,7 +263,8 @@ class Ora {
 		}
 
 		if (this.discardStdin && process.stdin.isTTY) {
-			this.startDiscardingStdin();
+			this.isDiscardingStdin = true;
+			stdinDiscarder.start();
 		}
 
 		this.render();
@@ -205,60 +286,14 @@ class Ora {
 			cliCursor.show(this.stream);
 		}
 
-		if (this.discardStdin && process.stdin.isTTY) {
-			this.stopDiscardingStdin();
+		if (this.discardStdin && process.stdin.isTTY && this.isDiscardingStdin) {
+			stdinDiscarder.stop();
+			this.isDiscardingStdin = false;
 		}
 
 		return this;
 	}
 
-	startDiscardingStdin() {
-		const {stdin} = process;
-
-		this._stdinOldRawMode = stdin.isRaw;
-		this._stdinOldEmit = stdin.emit;
-		this._stdinOldEmitOwnProperty = Object.prototype.hasOwnProperty.call(stdin, 'emit');
-
-		stdin.setRawMode(true);
-		stdin.on('data', noop);
-		stdin.resume();
-
-		const self = this;
-		stdin.emit = function (event, data, ...args) {
-			if (event === 'keypress') { // Fixes readline behavior
-				return;
-			}
-
-			if (event === 'data' && data.includes(ASCII_ETX_CODE)) {
-				process.emit('SIGINT');
-			}
-
-			self._stdinOldEmit.apply(this, [event, data, ...args]);
-		};
-	}
-
-	stopDiscardingStdin() {
-		if (this._stdinOldEmit !== undefined) {
-			const {stdin} = process;
-			stdin.setRawMode(this._stdinOldRawMode);
-			stdin.removeListener('data', noop);
-
-			if (stdin.listenerCount('data') === 0) {
-				stdin.pause();
-			}
-
-			if (this._stdinOldEmitOwnProperty) {
-				stdin.emit = this._stdinOldEmit;
-			} else {
-				delete stdin.emit;
-			}
-
-			this._stdinOldRawMode = undefined;
-			this._stdinOldEmit = undefined;
-			this._stdinOldEmitOwnProperty = undefined;
-		}
-	}
-
 	succeed(text) {
 		return this.stopAndPersist({symbol: logSymbols.success, text});
 	}