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node_modules/append-transform/index.js

@@ -0,0 +1,91 @@
+'use strict';
+const path = require('path');
+const js = require('default-require-extensions/js');
+
+module.exports = appendTransform;
+
+let count = 0;
+
+// eslint-disable-next-line node/no-deprecated-api
+function appendTransform(transform, ext = '.js', extensions = require.extensions) {
+	// Generate a unique key for this transform
+	const key = path.join(__dirname, count.toString());
+	count++;
+
+	let forwardGet;
+	let forwardSet;
+
+	const descriptor = Object.getOwnPropertyDescriptor(extensions, ext) || {value: js, configurable: true};
+
+	if (
+		((descriptor.get || descriptor.set) && !(descriptor.get && descriptor.set)) ||
+		!descriptor.configurable
+	) {
+		throw new Error('Somebody did bad things to require.extensions["' + ext + '"]');
+	}
+
+	if (descriptor.get) {
+		// Wrap a previous append-transform install and pass through to the getter/setter pair it created
+		forwardGet = function () {
+			return descriptor.get();
+		};
+
+		forwardSet = function (val) {
+			descriptor.set(val);
+			return forwardGet();
+		};
+	} else {
+		forwardGet = function () {
+			return descriptor.value;
+		};
+
+		forwardSet = function (val) {
+			descriptor.value = val;
+			return val;
+		};
+	}
+
+	function wrapCustomHook(hook) {
+		return function (module, filename) {
+			// We wrap every added extension, but we only apply the transform to the one on top of the stack
+			if (!module[key]) {
+				module[key] = true;
+
+				const originalCompile = module._compile;
+
+				// eslint-disable-next-line func-name-matching, func-names
+				module._compile = function replacementCompile(code, filename) {
+					module._compile = originalCompile;
+					code = transform(code, filename);
+					module._compile(code, filename);
+				};
+			}
+
+			hook(module, filename);
+		};
+	}
+
+	// Wrap the original
+	forwardSet(wrapCustomHook(forwardGet()));
+
+	const hooks = [forwardGet()];
+
+	function setCurrentHook(hook) {
+		const restoreIndex = hooks.indexOf(hook);
+
+		if (restoreIndex === -1) {
+			hooks.push(forwardSet(wrapCustomHook(hook)));
+		} else {
+			// We have already seen this hook, and it is being reverted (proxyquire, etc) - don't wrap again.
+			hooks.splice(restoreIndex + 1, hooks.length);
+			forwardSet(hook);
+		}
+	}
+
+	Object.defineProperty(extensions, ext, {
+		configurable: true,
+		enumerable: true,
+		get: forwardGet,
+		set: setCurrentHook
+	});
+}