Initial Save

node_modules/graphql/jsutils/inspect.js.flow

@@ -0,0 +1,126 @@
+// @flow strict
+
+import nodejsCustomInspectSymbol from './nodejsCustomInspectSymbol';
+
+const MAX_ARRAY_LENGTH = 10;
+const MAX_RECURSIVE_DEPTH = 2;
+
+/**
+ * Used to print values in error messages.
+ */
+export default function inspect(value: mixed): string {
+  return formatValue(value, []);
+}
+
+function formatValue(value, seenValues) {
+  switch (typeof value) {
+    case 'string':
+      return JSON.stringify(value);
+    case 'function':
+      return value.name ? `[function ${value.name}]` : '[function]';
+    case 'object':
+      if (value === null) {
+        return 'null';
+      }
+      return formatObjectValue(value, seenValues);
+    default:
+      return String(value);
+  }
+}
+
+function formatObjectValue(value, previouslySeenValues) {
+  if (previouslySeenValues.indexOf(value) !== -1) {
+    return '[Circular]';
+  }
+
+  const seenValues = [...previouslySeenValues, value];
+  const customInspectFn = getCustomFn(value);
+
+  if (customInspectFn !== undefined) {
+    // $FlowFixMe(>=0.90.0)
+    const customValue = customInspectFn.call(value);
+
+    // check for infinite recursion
+    if (customValue !== value) {
+      return typeof customValue === 'string'
+        ? customValue
+        : formatValue(customValue, seenValues);
+    }
+  } else if (Array.isArray(value)) {
+    return formatArray(value, seenValues);
+  }
+
+  return formatObject(value, seenValues);
+}
+
+function formatObject(object, seenValues) {
+  const keys = Object.keys(object);
+  if (keys.length === 0) {
+    return '{}';
+  }
+
+  if (seenValues.length > MAX_RECURSIVE_DEPTH) {
+    return '[' + getObjectTag(object) + ']';
+  }
+
+  const properties = keys.map(key => {
+    const value = formatValue(object[key], seenValues);
+    return key + ': ' + value;
+  });
+
+  return '{ ' + properties.join(', ') + ' }';
+}
+
+function formatArray(array, seenValues) {
+  if (array.length === 0) {
+    return '[]';
+  }
+
+  if (seenValues.length > MAX_RECURSIVE_DEPTH) {
+    return '[Array]';
+  }
+
+  const len = Math.min(MAX_ARRAY_LENGTH, array.length);
+  const remaining = array.length - len;
+  const items = [];
+
+  for (let i = 0; i < len; ++i) {
+    items.push(formatValue(array[i], seenValues));
+  }
+
+  if (remaining === 1) {
+    items.push('... 1 more item');
+  } else if (remaining > 1) {
+    items.push(`... ${remaining} more items`);
+  }
+
+  return '[' + items.join(', ') + ']';
+}
+
+function getCustomFn(object) {
+  const customInspectFn = object[String(nodejsCustomInspectSymbol)];
+
+  if (typeof customInspectFn === 'function') {
+    return customInspectFn;
+  }
+
+  if (typeof object.inspect === 'function') {
+    return object.inspect;
+  }
+}
+
+function getObjectTag(object) {
+  const tag = Object.prototype.toString
+    .call(object)
+    .replace(/^\[object /, '')
+    .replace(/]$/, '');
+
+  if (tag === 'Object' && typeof object.constructor === 'function') {
+    const name = object.constructor.name;
+    if (typeof name === 'string' && name !== '') {
+      return name;
+    }
+  }
+
+  return tag;
+}