planning

node_modules/tiny-warning/src/index.d.ts

@@ -0,0 +1 @@
+export default function warning(condition: any, message: string): void

node_modules/tiny-warning/src/index.js

@@ -0,0 +1,30 @@
+// @flow
+const isProduction: boolean = process.env.NODE_ENV === 'production';
+
+export default function warning(condition: mixed, message: string): void {
+  // don't do anything in production
+  // wrapping in production check for better dead code elimination
+  if (!isProduction) {
+    // condition passed: do not log
+    if (condition) {
+      return;
+    }
+
+    // Condition not passed
+    const text: string = `Warning: ${message}`;
+
+    // check console for IE9 support which provides console
+    // only with open devtools
+    if (typeof console !== 'undefined') {
+      console.warn(text);
+    }
+
+    // Throwing an error and catching it immediately
+    // to improve debugging
+    // A consumer can use 'pause on caught exceptions'
+    // https://github.com/facebook/react/issues/4216
+    try {
+      throw Error(text);
+    } catch (x) {}
+  }
+}