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node_modules/@rushstack/terminal/lib/TerminalTransform.js

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+"use strict";
+// Copyright (c) Microsoft Corporation. All rights reserved. Licensed under the MIT license.
+// See LICENSE in the project root for license information.
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.TerminalTransform = void 0;
+const TerminalWritable_1 = require("./TerminalWritable");
+/**
+ * The abstract base class for {@link TerminalWritable} objects that receive an input,
+ * transform it somehow, and then write the output to another `TerminalWritable`.
+ *
+ * @remarks
+ *
+ * The `TerminalTransform` and {@link SplitterTransform} base classes formalize the idea
+ * of modeling data flow as a directed acyclic graph of reusable transforms, whose
+ * final outputs are `TerminalWritable` objects.
+ *
+ * The design is based loosely on the `WritableStream` and `TransformStream` classes from
+ * the system {@link https://developer.mozilla.org/en-US/docs/Web/API/Streams_API/Concepts
+ * | Streams API}, except that instead of asynchronous byte streams, the `TerminalWritable`
+ * system synchronously transmits human readable messages intended to be rendered on a
+ * text console or log file.
+ *
+ * The main feature of the `TerminalTransform` class is its {@link TerminalTransform.destination}
+ * property, which tracks the next link in the graph.
+ *
+ * @public
+ */
+class TerminalTransform extends TerminalWritable_1.TerminalWritable {
+    constructor(options) {
+        super();
+        this.destination = options.destination;
+        this.preventDestinationAutoclose = !!options.preventDestinationAutoclose;
+    }
+    /** @override */
+    onClose() {
+        this.autocloseDestination();
+    }
+    /**
+     * The default implementation of {@link TerminalTransform.onClose} calls this
+     * method, which closes the {@link TerminalTransform.destination} if appropriate.
+     *
+     * @remarks
+     * The destination will not be closed if its {@link TerminalWritable.preventAutoclose}
+     * property is `true`.  The destination will not be closed if
+     * {@link ITerminalTransformOptions.preventDestinationAutoclose}
+     * is `true`.
+     *
+     * @sealed
+     */
+    autocloseDestination() {
+        if (!this.preventDestinationAutoclose && !this.destination.preventAutoclose) {
+            this.destination.close();
+        }
+    }
+}
+exports.TerminalTransform = TerminalTransform;
+//# sourceMappingURL=TerminalTransform.js.map