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node_modules/graphql/utilities/valueFromAST.mjs

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+import objectValues from "../polyfills/objectValues.mjs";
+import keyMap from "../jsutils/keyMap.mjs";
+import inspect from "../jsutils/inspect.mjs";
+import invariant from "../jsutils/invariant.mjs";
+import { Kind } from "../language/kinds.mjs";
+import { isLeafType, isInputObjectType, isListType, isNonNullType } from "../type/definition.mjs";
+/**
+ * Produces a JavaScript value given a GraphQL Value AST.
+ *
+ * A GraphQL type must be provided, which will be used to interpret different
+ * GraphQL Value literals.
+ *
+ * Returns `undefined` when the value could not be validly coerced according to
+ * the provided type.
+ *
+ * | GraphQL Value        | JSON Value    |
+ * | -------------------- | ------------- |
+ * | Input Object         | Object        |
+ * | List                 | Array         |
+ * | Boolean              | Boolean       |
+ * | String               | String        |
+ * | Int / Float          | Number        |
+ * | Enum Value           | Mixed         |
+ * | NullValue            | null          |
+ *
+ */
+
+export function valueFromAST(valueNode, type, variables) {
+  if (!valueNode) {
+    // When there is no node, then there is also no value.
+    // Importantly, this is different from returning the value null.
+    return;
+  }
+
+  if (valueNode.kind === Kind.VARIABLE) {
+    var variableName = valueNode.name.value;
+
+    if (variables == null || variables[variableName] === undefined) {
+      // No valid return value.
+      return;
+    }
+
+    var variableValue = variables[variableName];
+
+    if (variableValue === null && isNonNullType(type)) {
+      return; // Invalid: intentionally return no value.
+    } // Note: This does no further checking that this variable is correct.
+    // This assumes that this query has been validated and the variable
+    // usage here is of the correct type.
+
+
+    return variableValue;
+  }
+
+  if (isNonNullType(type)) {
+    if (valueNode.kind === Kind.NULL) {
+      return; // Invalid: intentionally return no value.
+    }
+
+    return valueFromAST(valueNode, type.ofType, variables);
+  }
+
+  if (valueNode.kind === Kind.NULL) {
+    // This is explicitly returning the value null.
+    return null;
+  }
+
+  if (isListType(type)) {
+    var itemType = type.ofType;
+
+    if (valueNode.kind === Kind.LIST) {
+      var coercedValues = [];
+
+      for (var _i2 = 0, _valueNode$values2 = valueNode.values; _i2 < _valueNode$values2.length; _i2++) {
+        var itemNode = _valueNode$values2[_i2];
+
+        if (isMissingVariable(itemNode, variables)) {
+          // If an array contains a missing variable, it is either coerced to
+          // null or if the item type is non-null, it considered invalid.
+          if (isNonNullType(itemType)) {
+            return; // Invalid: intentionally return no value.
+          }
+
+          coercedValues.push(null);
+        } else {
+          var itemValue = valueFromAST(itemNode, itemType, variables);
+
+          if (itemValue === undefined) {
+            return; // Invalid: intentionally return no value.
+          }
+
+          coercedValues.push(itemValue);
+        }
+      }
+
+      return coercedValues;
+    }
+
+    var coercedValue = valueFromAST(valueNode, itemType, variables);
+
+    if (coercedValue === undefined) {
+      return; // Invalid: intentionally return no value.
+    }
+
+    return [coercedValue];
+  }
+
+  if (isInputObjectType(type)) {
+    if (valueNode.kind !== Kind.OBJECT) {
+      return; // Invalid: intentionally return no value.
+    }
+
+    var coercedObj = Object.create(null);
+    var fieldNodes = keyMap(valueNode.fields, function (field) {
+      return field.name.value;
+    });
+
+    for (var _i4 = 0, _objectValues2 = objectValues(type.getFields()); _i4 < _objectValues2.length; _i4++) {
+      var field = _objectValues2[_i4];
+      var fieldNode = fieldNodes[field.name];
+
+      if (!fieldNode || isMissingVariable(fieldNode.value, variables)) {
+        if (field.defaultValue !== undefined) {
+          coercedObj[field.name] = field.defaultValue;
+        } else if (isNonNullType(field.type)) {
+          return; // Invalid: intentionally return no value.
+        }
+
+        continue;
+      }
+
+      var fieldValue = valueFromAST(fieldNode.value, field.type, variables);
+
+      if (fieldValue === undefined) {
+        return; // Invalid: intentionally return no value.
+      }
+
+      coercedObj[field.name] = fieldValue;
+    }
+
+    return coercedObj;
+  } // istanbul ignore else (See: 'https://github.com/graphql/graphql-js/issues/2618')
+
+
+  if (isLeafType(type)) {
+    // Scalars and Enums fulfill parsing a literal value via parseLiteral().
+    // Invalid values represent a failure to parse correctly, in which case
+    // no value is returned.
+    var result;
+
+    try {
+      result = type.parseLiteral(valueNode, variables);
+    } catch (_error) {
+      return; // Invalid: intentionally return no value.
+    }
+
+    if (result === undefined) {
+      return; // Invalid: intentionally return no value.
+    }
+
+    return result;
+  } // istanbul ignore next (Not reachable. All possible input types have been considered)
+
+
+  false || invariant(0, 'Unexpected input type: ' + inspect(type));
+} // Returns true if the provided valueNode is a variable which is not defined
+// in the set of variables.
+
+function isMissingVariable(valueNode, variables) {
+  return valueNode.kind === Kind.VARIABLE && (variables == null || variables[valueNode.name.value] === undefined);
+}