fix: correct custom data type resolution

Author: gajus

src/utilities/createLoaderTypePropertyDeclaration.js

@@ -1,9 +1,14 @@
 // @flow
 
+import Logger from '../Logger';
 import formatTypeName from './formatTypeName';
 import isNumberType from './isNumberType';
 import isStringType from './isStringType';
 
+const log = Logger.child({
+  namespace: 'createLoaderTypePropertyDeclaration'
+});
+
 export default (loaderName: string, dataTypeName: string, resourceName: string, resultIsArray: boolean) => {
   let keyType: 'number' | 'string';
 
@@ -12,7 +17,14 @@ export default (loaderName: string, dataTypeName: string, resourceName: string,
   } else if (isStringType(dataTypeName)) {
     keyType = 'string';
   } else {
-    throw new Error('Unexpected state.');
+    log.error({
+      dataTypeName,
+      loaderName,
+      resourceName,
+      resultIsArray
+    }, 'key type cannot be resolved to a string or number');
+
+    throw new Error('Cannot resolve key type.');
   }
 
   if (resultIsArray) {

src/utilities/generateFlowTypeDocument.js

@@ -17,7 +17,7 @@ const generateFlowTypeDeclarationBody = (columns: $ReadOnlyArray<ColumnType>, da
   const propertyDeclarations = [];
 
   for (const column of sortedColumns) {
-    const propertyDataType = dataTypeMap[column.dataType] ? dataTypeMap[column.dataType] : getFlowType(column.dataType);
+    const propertyDataType = dataTypeMap[column.dataType] ? getFlowType(dataTypeMap[column.dataType]) : getFlowType(column.dataType);
 
     propertyDeclarations.push('+' + formatPropertyName(column.name) + ': ' + propertyDataType + (column.isNullable ? ' | null' : ''));
   }